Insulin Resistance Unveiled: Cushing’s Disease in a Patient with Type 1 Diabetes Mellitus and Worsening Glycemic Control

Highlights

  • Coexistence of hypercortisolism secondary to ACTH-producing pituitary adenoma and type 1 diabetes mellitus.
  • Presentation of Cushing’s disease in individuals with type 1 diabetes mellitus.
  • Automated insulin delivery utilization in type 1 diabetes with comorbid refractory hypercortisolism.

ABSTRACT

Background/Objective

Type 1 diabetes mellitus is an autoimmune disease often characterized by endogenous insulin deficiency and often sensitivity to endogenous insulin administration. Cushing’s disease, though rare, should be considered as a cause of insulin resistance and increased insulin requirements in individuals with type 1 diabetes mellitus.

Case Presentation

A 21-year-old female with type 1 diabetes mellitus presented with steadily increasing insulin requirements via her hybrid closed-loop insulin pump. She subsequently developed hypertension, weight gain, violaceous striae, and cystic acne. Laboratory evaluation revealed unsuppressed cortisol of 16.6 μg/dL after a 1-mg dexamethasone suppression test, with a simultaneous adrenocorticotropin hormone level of 73.3 pg/mL. Pituitary MRI showed a 1.9 cm sellar mass with local invasion. She underwent transsphenoidal hypophysectomy. Postoperative cortisol was 8.9 μg/dL after intraoperative dexamethasone exposure. Residual hypercortisolism was confirmed, necessitating gamma knife radiation and pharmacologic treatment with a steroidogenesis inhibitor.

Discussion

We present a case of Cushing’s disease due to a corticotropin-secreting pituitary macroadenoma in a young woman with type 1 diabetes. Her initial presentation included rising insulin requirements, followed by overt hypercortisolism. Despite surgery, persistent hypercortisolism required further intervention with gamma knife radiation and osilodrostat. She experienced reductions in both weight and insulin needs, with normalization of cortisol levels on maintenance osilodrostat.

Conclusion

Cushing’s syndrome should be considered in the differential diagnosis of patients with type 1 diabetes and increasing insulin requirements. This case underscores the importance of regular review of automated insulin delivery data and consideration of endocrine causes of insulin resistance and increased insulin requirements in those with type 1 diabetes.

KEY WORDS

Type 1 Diabetes Mellitus
T1DM
Cushing’s disease
Insulin resistance
Insulin pump
Total Daily Dose
TDD

Introduction

Cushing’s syndrome occurs as the result of prolonged elevation in plasma cortisol which can lead to adverse effects including insulin resistance, hyperglycemia, hypertension, weight gain, immunosuppression, and neurocognitive changes. Cushing’s syndrome can occur due to exogenous exposure to corticosteroids or endogenous cortisol hypersecretion. The most common etiology of endogenous hypercortisolism is Cushing’s disease secondary to a corticotrophin-secreting pituitary tumor. In 90% of cases of Cushing’s disease, patients present with pituitary microadenomas, with only 10% of patients presenting with pituitary tumors >1 cm1.
Type 1 diabetes mellitus is an autoimmune condition characterized by T-cell mediated destruction of pancreatic beta cells with ultimate inability to produce insulin and subsequent insulin dependence2. Over the last decade, there has been significant advancement in diabetes management strategies and insulin delivery with creation of hybrid closed-loop insulin pump technology used in conjunction with continuous glucose monitoring systems to provide automated insulin delivery. Within the field of endocrinology, this has required a shift in both the interpretation of glycemic data, insulin utilization data, as well as a pivot to approaching titration of insulin pump settings. Assessment of total daily basal and total daily dose (TDD) in automated mode is of utmost importance when utilizing automated insulin delivery as the amount of insulin utilized can vary significantly in comparison to fixed quantities seen with use of manual mode in an insulin pump2,3.
Type 1 diabetes mellitus is typically characterized by relative insulin sensitivity, particularly early in the disease course. Patients can develop insulin resistance over time, particularly in the setting of comorbid obesity. However, we present a case of a young woman with type 1 diabetes mellitus presenting with steadily increasing insulin requirements followed by development of overt Cushing’s secondary to corticotropin-secreting pituitary macroadenoma. She was utilizing a hybrid-closed loop insulin pump technology with insulin pump download indicating diminished glycemic control despite a steady increase in total daily insulin requirements. This is only the third reported case of Cushing’s disease in a person living with type 1 diabetes mellitus4,5.

Case Presentation

A 21-year-old female with a history of type 1 diabetes diagnosed at age 11 in the context of admission for diabetic ketoacidosis initially presented to adult endocrinology for routine outpatient diabetes management. Type 1 Diabetes Mellitus was managed with automated hybrid-closed loop insulin pump technology (Tandem T-slim X:2 with Dexcom G6 continuous glucose monitoring system). Her hemoglobin A1c was 6.2% with a review of her continuous glucose monitoring system indicating time in range of 73% with 21% of blood glucose levels >180 mg/dL. At that time, she reported concerns regarding high insulin requirements despite an active lifestyle as she was running out of insulin for use in pump early. She was noted to have significant prandial insulin requirements with insulin to carbohydrate ratio of 1 unit for every 3.0-4.5 carbohydrates, raising concern for insulin resistance. Over the next 16 months, she had weight gain of 15.8 kg with elevation in blood pressure and worsening hyperglycemia. Review of her insulin pump downloads indicated a steady increase in her total daily insulin requirements of close to 30%, coupled with reduced time in range and increase in HbA1c.
On repeat physical examination, the development of cystic acne, trace pitting pedal edema, and purple violaceous striae on the abdomen, hips, and thighs were observed. She was also noted to have a new elevation of blood pressure to 162/101 mm Hg. She declined exposure to exogenous corticosteroids (including oral, topical or intra-articular formulations). Based on clinical examination and changes in insulin requirements, the decision was made to evaluate for hypercortisolism. Laboratory evaluation at that time revealed unsuppressed 08:00 AM cortisol level of 16.6 ug/dL after 1 mg of dexamethasone the evening prior. Dexamethasone level was confirmed to be more than adequate at 418 ng/dL (reference range for 8:00 AM level following 1 mg dexamethasone previous evening: 140-295 ng/dL). A simultaneous ACTH level was elevated at 73.3 pg/mL (reference range: 7.2-63.3 pg/mL). She was also noted to have midnight salivary cortisol levels of 0.646, 0.290, and 0.350 ug/dL on three consecutive evenings (reference range <0.010-0.090 ug/dL).
She then underwent MRI pituitary with and without gadolinium enhancement which revealed 1.8 x 1.9 cm enhancing sellar mass with invasion of the right cavernous sinus, extension around the right internal carotid artery, as well as posteriorly down the dorsal aspect of the clivus (Figures 1 and 2). As both hypercortisolism as well as type 1 diabetes mellitus have been implicated as etiologies for lower bone density with subsequent increased risk of osteoporosis later in life, bone densometry was also obtained for this patient. She was found to have low bone mineral density for her age with Z-score of the lumbar spine of -3.2, Z-score of the femoral neck of -2.3, and Z-score of the total hip of -2.8.

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Figure 1. MRI pituitary coronal image revealing sellar mass with invasion of the right cavernous sinus, extension around the right internal carotid artery.

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Figure 2. MRI pituitary sagittal image revealing 1.8 x 1.9 cm sellar mass.

She was evaluated by neurosurgery and underwent endoscopic trans-sphenoidal resection of pituitary macroadenoma. Pathology revealed immunoreactivity for neuroendocrine marker INSM1 (Insulinoma-associated protein 1) and adrenocorticotropic hormone. The lesion was negative for immunoreactivity for prolactin, growth hormone, thyroid-stimulating hormone, follicle-stimulating hormone, and beta-luteinizing hormone.
The cortisol level was 8.9 ug/dL on post-operative day 1. It is notable that she had received 10 mg of intravenous Dexamethasone intraoperatively, raising concern for residual tumor. On post-operative day 3, cortisol level was 4.1 mcg/dL with ACTH level of 94.5 pg/mL. Repeat random cortisol level was 16.3 mcg/dL with simultaneous ACTH level of 63.3 pg/mL. Upon being discharged home, a repeat 24-hour urinary free cortisol was obtained in the outpatient setting and found to be elevated at 464 ug/24 hours (reference range: 6-42 ug/24 hours), consistent with refractory hypercortisolism (Table 1Figure 4). She was then initiated on osilodrostat, a steroidogenesis inhibitor approved by the FDA in 2020 for use in refractory Cushing’s disease after pituitary surgery. Osilodrostat works via inhibition of 11β-hydroxylase and aldosterone synthase to inhibit the production of cortisol and aldosterone6,7. She underwent ongoing up titration to a maintenance dose of osilodrostat 7 mg twice daily with additional insulin pump titrations over a 2-year duration. Urinary free cortisol was monitored as this is the gold standard for monitoring refractory Cushing’s and the preferred modality for monitoring cortisol levels in individuals on osilodrostat. Final repeat 24-hour urine free cortisol level normalized to 35 ug/24 hours and TDD of insulin via automatic insulin delivery system was lower than time of diagnosis of pituitary Cushing’s at 96 units per day despite having had a roughly 27 kg weight gain (Table 1Figure 4).

Table 1. Weight trends as well as TDD of insulin listed along with glycemic parameters from automated insulin dosing system Tandem T-slim X:2 with automated mode utilizing Decom G6 CGM. 24-hour urine cortisol collection data included to highlight degree of hypercortisolism. Treatments denoted by asterisk in table include

Date Weight (kg) Total daily insulin dose (units/day) HbA1c (%) Time in range (%) Urine cortisol (mcg/24 hours); RR 6-42 mcg/24 hours
03/2021 72.7 99.25 6.2 73
06/2021 74.5 109.56 6.6 73
12/2021 80.0 117.17 6.9 62
05/2022 88.5 126.84 6.9 57
11/2022
12/2022 93.8 124.15 7.0 61 464
01/2023∗∗
02/2023 35
06/2023∗∗∗
06/2023 100.4 122.76 7.0 54
07/2023 137
12/2023 100.9 130.34 6.8 48 48
08/2024 106 125 6.9 58 76
02/2025 100 96 5.8 76 42
Transsphenoidal resection.
∗∗
Osilodrostat initiated.
∗∗∗
Gamma knife radiosurgery.

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Figure 3. MRI pituitary coronal image revealing right eccentric heterogenous enhancing sellar mass which is decreased in size. Redemonstrated residual tissue around the right carotid artery.

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Figure 4. Graphical representation of weight (kg), total daily dose of insulin (units per day), and 24-hour urine cortisol measurements (mcg/24 hours).

Due to ongoing hypercortisolism, repeat MRI pituitary with and without gadolinium enhancement was obtained and revealed residual disease in the right sella with right cavernous sinus involvement and extending posteriorly along the dorsal aspect of the clivus (Figure 3). She had subsequent consultation with neurosurgery at which time the decision made to proceed with single-fraction gamma knife stereotactic radiosurgery. She received additional treatment of gamma knife radiosurgery with dose of 18 Gy to target residual pituitary disease.

Discussion

We present, to our knowledge, the third reported case of Cushing’s disease due to a corticotropin-secreting pituitary adenoma in an individual with type 1 diabetes. Prolonged hypercortisolism, as seen in this case, is associated with obesity, hypertension, decreased bone density, insulin resistance, and decreased glucose control. Hypercortisolism is most commonly caused by chronic exogenous corticosteroid exposure however, endogenous hypercortisolemia should be considered as a potential etiology of worsening glycemia and insulin resistance in individuals with diabetes mellitus.
The coexistence of Cushing’s disease secondary to a corticotropin-secreting pituitary macroadenoma in an individualwith type 1 diabetes mellitus is exceedingly rare. Furthermore, only 10% of pituitary Cushing’s cases present with macroadenomas at the time of diagnosis. Several studies indicate that smaller lesions at the time of diagnosis and earlier diagnosis of Cushing’s disease are associated with reduced risk of disease recurrence6,7,8. In this case, a young female presented with a macroadenoma at the time of diagnosis and had residual post-operative hypercortisolism requiring gamma knife radiation and pharmacologic intervention with osilodrostat, a steroidogenesis inhibitor approved by the FDA in 2020 for use in refractory Cushing’s disease after pituitary surgery. Osilodrostat works via inhibition of 11β-hydroxylase and aldosterone synthase to inhibit the production of cortisol and aldosterone9,10. Of the two other reported cases of comorbid type 1 diabetes and Cushing’s disease, one individual presented with a macroadenoma at the time of diagnosis. This case occurred in a pediatric male with type 1 diabetes mellitus who was ultimately admitted to the hospital with worsening headaches in the setting of pituitary apoplexy. Prior to hospitalization, this individual showed numerous clinical stigmata of hypercortisolism.
Other contributors to increased insulin resistance, such as obesity, infection, stress, and concurrent glucocorticoids, should also be considered in the differential diagnosis when evaluating etiologies for unexplained changes in glycemic control. However, this case emphasizes the importance of considering the possibility of comorbid Cushing’s disease in persons with type 1 diabetes mellitus. This is imperative to mitigate the consequences of prolonged hypercortisolism and to potentially aid in earlier diagnosis. In this case, declining glucose control and increasing insulin requirements were noted prior to other overt clinical findings of hypercortisolism. Thus, this case also underscores the importance of steadfast evaluation of insulin dose requirements for individuals using continuous insulin infusion devices (particularly hybrid closed-loop automated insulin delivery [AID] systems). With growing emphasis on the review and utilization of the one-page ambulatory glucose profile, it is important to also review insulin pump settings and insulin delivery for those utilizing these systems as automated insulin delivery profile for total daily dose can change and should be reviewed at each visit.

Conclusion

In closing, this case emphasizes the importance of considering secondary endocrine disorders in those living with diabetes mellitus who experience sudden or unexplained changes in glycemic control and insulin requirements. Although rare, coexistence of type 1 diabetes and Cushing’s disease can occur. Prompt recognition and treatment of the underlying Cushing’s disease can lead to significant improvements in insulin sensitivity and glycemic outcomes. This report reinforces the need for multidisciplinary management of vigilant monitoring in patients with coexisting endocrine pathologies, particularly when advanced diabetes technologies are in use. Ultimately, it highlights the critical role of clinical suspicion and timely intervention in optimizing outcomes for complex endocrine cases.

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References

Long-Term Obesity Persists Despite Pituitary Adenoma Treatment In Childhood

Sethi A, et al. Clin Endocrinol. 2019;doi:10.1111/CEN.14146.

January 5, 2020

Obesity is common at diagnosis of pituitary adenoma in childhood and may persist despite successful treatment, according to findings published in Clinical Endocrinology.

“The importance of childhood and adolescent obesity on noncommunicable disease in adult life is well recognized, and in this new cohort of patients, we report that obesity is common at presentation of pituitary adenoma in childhood and that successful treatment is not necessarily associated with weight loss,” Aashish Sethi, MD, MBBS, a pediatric endocrinologist in the department of endocrinology at Alder Hey Children’s Hospital in Liverpool, United Kingdom, and colleagues wrote. “We have reported obesity, and obesity-related morbidity in a mixed cohort of children and young adults previously, but [to] our knowledge, this is the first time this observation has been reported in a purely pediatric cohort.”

In a retrospective study, Sethi and colleagues analyzed clinical and radiological data from 24 white children from Alder Hey Children’s Hospital followed for a median of 3.3 years between 2000 and 2019 (17 girls; mean age at diagnosis, 15 years). Researchers assessed treatment modality (medical, surgical or radiation therapy), pituitary hormone deficiencies and BMI, as well as results of any genetic testing.

Within the cohort, 13 girls had prolactinomas (mean age, 15 years), including 10 macroadenomas between 11 mm and 35 mm in size. Children presented with menstrual disorders (91%), headache (46%), galactorrhea (46%) and obesity (38%). Nine children were treated with cabergoline alone, three also required surgery, and two were treated with the dopamine agonist cabergoline, surgery and radiotherapy.

Five children had Cushing’s disease (mean age, 14 years; two girls), including one macroadenoma. Those with Cushing’s disease presented with obesity (100%), short stature (60%) and headache (40%). Transsphenoidal resection resulted in biochemical cure; however, two patients experienced relapse 3 and 6 years after surgery, respectively, requiring radiotherapy. One patient also required bilateral adrenalectomy.

Six children had a nonfunctioning pituitary adenoma (mean age, 16 years; two girls), including two macroadenomas. These children presented with obesity (67%), visual field defects (50%) and headache (50%). Four required surgical resections, with two experiencing disease recurrence after surgery and requiring radiotherapy.

During the most recent follow-up exam, 13 children (54.1%) had obesity, including 11 who had obesity at diagnosis.

“The persistence of obesity following successful treatment, in patients with normal pituitary function, suggests that mechanisms other than pituitary hormone excess or deficiency may be important,” the researchers wrote. “It further signifies that obesity should be a part of active management in cases of pituitary adenoma from diagnosis.” – by Regina Schaffer

Disclosures: The authors report no relevant financial disclosures.

From https://www.healio.com/endocrinology/adrenal/news/online/%7Bde3fd83b-e8e0-4bea-a6c2-99eb896356ab%7D/long-term-obesity-persists-despite-pituitary-adenoma-treatment-in-childhood

Consecutive Resections of Double Pituitary Adenoma for Resolution of Cushing Disease

BACKGROUND

Double pituitary adenomas are rare presentations of two distinct adenohypophyseal lesions seen in <1% of surgical cases. Increased rates of recurrence or persistence are reported in the resection of Cushing microadenomas and are attributed to the small tumor size and localization difficulties. The authors report a case of surgical treatment failure of Cushing disease because of the presence of a secondary pituitary adenoma.

OBSERVATIONS

A 32-year-old woman with a history of prolactin excess and pituitary lesion presented with oligomenorrhea, weight gain, facial fullness, and hirsutism. Urinary and nighttime salivary cortisol elevation were elevated. Magnetic resonance imaging confirmed a 4-mm3 pituitary lesion. Inferior petrosal sinus sampling was diagnostic for Cushing disease. Primary endoscopic endonasal transsphenoidal resection was performed to remove what was determined to be a lactotroph-secreting tumor on immunohistochemistry with persistent hypercortisolism. Repeat resection yielded a corticotroph-secreting tumor and postoperative hypoadrenalism followed by long-term normalization of the hypothalamic-pituitary-adrenal axis.

LESSONS

This case demonstrates the importance of multidisciplinary management and postoperative hormonal follow-up in patients with Cushing disease. Improved strategies for localization of the active tumor in double pituitary adenomas are essential for primary surgical success and resolution of endocrinopathies.

ABBREVIATIONS

ACTH = adrenocorticotrophic hormone;  BMI = body mass index;  DHEA-S = dehydroepiandrosterone sulfate;  FSH = follicle-stimulating hormone;  GH = growth hormone;  IHC = immunohistochemical;  IPSS = inferior petrosal sinus sampling;  LH = luteinizing hormone;  MRI = magnetic resonance imaging;  POD = postoperative day;  T4 = thyroxine;  TF = transcription factor;  TSH = thyroid-stimulating hormone;  UFC = urinary free cortisol

Pituitary adenomas are adenohypophyseal tumors that can cause endocrinopathies, such as pituitary hormone hypersecretion or anterior hypopituitarism. Cell lineages are used to classify these tumors on the basis of immunohistochemical (IHC) staining of transcription factors, hormones, and other biomarkers.1 Pituitary adenomas differentiate from pluripotent stem cells along one of three lineage pathways, depending on the following active transcription factors (TFs): pituitary transcription factor 1 (PIT-1), T-box transcription factor (TPIT), or steroidogenic factor-1 (SF-1). Rarely, two or more discrete pituitary adenomas from different lineages are identified in patients; however, the etiology remains unclear.2 The incidence of multiple pituitary adenomas has been reported to be 1%–2% of all resected pituitary adenomas but is likely underestimated based on data from large autopsy series.1–4 Pluri-hormonal adenomas are also rare entities in which a single tumor contains multiple TF lineages with one or more hormonal excesses.1–3 Preoperative recognition of multiple or pluri-hormonal pituitary adenomas is rare, and most tumors are discovered incidentally upon autopsy, intraoperatively, or on histological analysis.2,3,5

In cases of multiple synchronous pituitary adenomas, only one hormone excess syndrome is most frequently evident on clinical presentation and endocrine workup. Silent pituitary tumors positive for prolactin on immunohistochemistry are the most prevalent additional, incidentally found tumor in cases of multiple pituitary adenomas.5 This is particularly true in Cushing disease.6,7 It is important to recognize the presence of multiple pituitary adenomas especially in the setting of hormonally active pituitary adenomas to provide optimal management for this subset of patients. Complete resection is curative for Cushing disease with the standard of care achieved through a transsphenoidal approach. Localization of the tumor presents a challenge because of suboptimal sensitivity of magnetic resonance imaging (MRI) in demonstrating microadenomas, the inconsistency of lateralization with inferior petrosal sinus sampling (IPSS), and delays in pathological analysis.1,8,9 Additionally, the presence of an additional pituitary adenoma can obscure the microtumor through its large size and mass effect and can act as a “decoy lesion” during MRI, IPSS, and resection.6

Consideration of multiple pituitary tumors is necessary for successful resection. In a patient with a biochemical picture of Cushing disease, the demonstration of an adenoma with negative adrenocorticotrophic hormone (ACTH) immunostaining and the absence of postoperative hypoadrenalism may indicate the existence of a double adenoma. Few cases have described a lack of remission of an endocrinopathy after transsphenoidal resection due to the presence of an additional adenoma,2,6,10 and even less so in the instance of the persistence of Cushing disease.6 We present a rare case of double pituitary adenomas in a patient presenting with Cushing disease who underwent two endoscopic endonasal transsphenoidal resections and immunostaining for prolactin and ACTH, respectively, with long-term normalization of her hypothalamic-pituitary-adrenal (HPA) axis.

Illustrative Case

History and Presentation

A 32-year-old female, gravida 0 para 0, with a history of a pituitary lesion and hyperprolactinemia presented to our institution for the evaluation for Cushing disease. Ten years earlier, the patient had presented to a gynecologist with hirsutism, galactorrhea, and oligomenorrhea. Her endocrine workup was remarkable for an elevated prolactin at 33.8 ng/mL (2.3–23.3 ng/mL), while follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH) levels were normal. No ACTH or cortisol levels were available. MRI demonstrated a 5 × 6 × 5–mm T1-weighted isointense pituitary lesion protruding into the suprasellar cistern due to a small sella size. She was treated with bromocriptine 2.5 mg daily for 5 years, with normalization of her prolactin level. Subsequent MRI demonstrated a stable lesion size and T1 and T2 hyperintensity in the region of the known pituitary lesion, considered to be posttreatment cystic change with proteinaceous contents and blood. After the normalization of her prolactin levels, she continued to have oligomenorrhea and abnormal hair growth. Polycystic ovaries were not visualized on ultrasound. She was started on oral contraceptives and then switched to the etonorgestrel implant.

A decade after initial presentation, she presented to endocrinology at our institution with 3 years of weight gain, hirsutism, and potential oligomenorrhea. Vital signs were stable (blood pressure: 122/86; heart rate: 72 beats/min), and facial fullness and striae on her bilateral breasts were appreciated on physical examination. She was taking isoniazid and pyridoxine for a recent diagnosis of latent tuberculosis and had discontinued bromocriptine 5 years earlier. Her weight was 66.3 kg and body mass index (BMI) was 23.9 kg/m2. She reported that her maternal uncle had a pituitary tumor. Laboratory analysis was positive for elevated urinary free cortisol (UFC) of 109 µg per 24 hours (2.5–45 µg/24 h; Table 1) and nighttime salivary cortisol of 142 ng/mL (<100 ng/dL) with high-normal prolactin of 22.8 ng/mL (2.3–23.3 ng/dL) and normal FSH, LH, TSH, and thyroxine (T4). Dehydroepiandrosterone sulfate (DHEA-S) was 128 µg/dL (98.8–340.0 µg/dL). Imaging demonstrated a 4 × 4 × 4–mm pituitary lesion with decreased T1-weighted and increased central T2-weighted signal intensity in the left lateral pituitary (Fig. 1A–C). Desmopressin (Ferring Pharmaceuticals DDAVP) stimulation increased a basal ACTH of 49.9 pg/mL to ACTH of 91.2 pg/mL, and cortisol increased from 13.7 µg/dL to 21.2 µg/dL, consistent with neoplastic hypercortisolism. IPSS was performed, which showed a right-sided, central-to-peripheral ACTH gradient (Table 2). The patient elected to undergo endoscopic endonasal resection with the initial target as the left-lateral pituitary mass to achieve a cure for Cushing disease.

TABLE 1Urinary free cortisol at baseline and 3, 5, and 7 months after the primary resection

Variable Baseline 3 Mos 5 Mos 7 Mos on Osilodrostat
Urinary free cortisol (4–50 µg/24 hrs) 109 134.2 125.4 40.3
Urinary creatinine (0.5–2.5 g/24 hrs) 0.995 1.17 1.42 1.11
Urinary vol (mL) 1950 2300 2100 2125
FIG. 1
FIG. 1

Preoperative coronal precontrast (A) and postcontrast (B) T1-weighted magnetic resonance imaging (MRI) and T2-weighted MRI (C) demonstrated a 4-mm3 lesion (arrows) with decreased T1 and increased central T2 signal intensity in the left lateral pituitary. Two days after surgery, coronal precontrast (D) and postcontrast T1-weighted (E) and T2-weighted (F) MRI demonstrated the unchanged adenoma.

TABLE 2Preoperative inferior petrosal sinus sampling with corticorelin ovine triflutate 68 µg

Time (mins) ACTH (pg/mL) Prolactin (ng/mL)
Peripheral Petrosal Sinus ACTH Ratio Peripheral Petrosal Sinus Prolactin Ratio
Rt Lt Rt Lt Rt Lt Rt Lt
−5 50.6 225 1586 4.45 31.34 21 124 295 5.90 14.05
0 48.8 389 1376 7.97 28.20 22.2 185 198 8.33 8.92
3 69.8 4680 1333 67.05 19.1 22.1 396 32.5 17.92 1.47
5 80.9 4590 1623 56.74 20.06 22.1 436 32.2 19.73 1.46
10 112 4160 1660 37.14 14.82 20.2 367 42 17.90 2.05

ACTH or prolactin ratio = inferior petrosal sinus ACTH or prolactin/peripheral blood ACTH or prolactin.

Primary Resection and Outcomes

During the primary resection, abnormal tissue was immediately visible after a linear incision along the bottom of the dura, with an excellent plane of dissection. The inferomedial adenoma was distinct from the known left lateral lesion, and the resection was considered complete by the primary neurosurgeon. Subsequently, the left-sided adenoma was not pursued because of the historical prolactinoma diagnosis and an assumption that the newly discovered adenoma was the cause of ACTH hypersecretion. However, pathology of the inferomedial tumor was strongly and diffusely positive for prolactin (Fig. 2B), synaptophysin, and cytokeratin, with an Mindbomb Homolog-1 (MIB-1) proliferative index of 2.4%. ACTH, growth hormone (GH), FSH, LH, and TSH immunostaining were negative. TF immunohistochemistry was not available. On postoperative day (POD) 1, pituitary MRI was performed and demonstrated the unchanged 4-mm3 T1-weighted hypointense lesion with small central T2-weighted hyperintensity in the left lateral gland (Fig. 1D–F). Cortisol levels ranged from 9.7 to 76.2 µg/dL (4.8–19.5 µg/dL), and ACTH was 19.5 pg/mL (7.2–63.3 pg/mL) on POD 1.

FIG. 2
FIG. 2

Histological examination of surgical specimens from the inferomedial (A–C) and left lateral (D–F) lesions. The initial resection (hematoxylin and eosin [H&E], A) was strongly and diffusely positive for prolactin (B) with normal reticulin levels (C) indicating a lactotrophic pituitary adenoma. The second operation (H&E, D) was diagnostic for a corticotropic pituitary adenoma with diffusely positive adrenocorticotrophic hormone (ACTH) (E) and decreased reticulin (F). Original magnification ×100.

Early reoperation was discussed with the patient based on the pathology and persistent hypercortisolism; however, she elected to pursue conservative management with close follow-up. Postoperative cortisol nadir was 4.8 µg/dL (4.8–19.5 µg/dL) on POD 2 during her 4-day hospital stay. DHEA-S was significantly decreased from baseline at 22.3 µg/dL (98.8–340.0 µg/dL) and a prolactin level of 3.4 ng/mL (2.3–23.3 ng/dL) was low-normal. No glucocorticoids were administered during her hospital course. There was no clinical evidence of vasopressin deficiency while she was an inpatient.

Three months postoperatively, the patient reported insomnia, poor hair quality, fatigue, nocturnal sweating, and continued increasing weight gain with fat accumulation in the supraclavicular and dorsal cervical area. She had one spontaneous menstrual period despite the use of etonogestrel implant. UFC was increased at 134.2 µg/24 hours (4–50 µg/24 h; Table 1). The 8:00 am serum cortisol was 10.2 µg/dL (5.0–25.0 µg/dL). She was started on osilodrostat 2 mg twice daily for her persistent hypercortisolism, and she reported some clinical improvement; however, she had continued elevation in her late-night salivary cortisol levels up to 7.0 nmol/L. Other endocrine lab work was normal, with a prolactin of 13.5 ng/mL (2.8–23.3 ng/mL) and TSH of 3.67 µIU/mL (0.4–4.0 µIU/mL). Her weight had increased by 4.9 kg to 71.2 kg with a BMI of 25.3 kg/m2. Approximately 6 months postoperatively, she was amenable to a secondary resection targeting the remaining left lateral pituitary adenoma.

Secondary Resection and Outcomes

After obtaining adequate exposure for the secondary resection, the lesion in the left lateral aspect of the pituitary was targeted. The tumor was clearly identified and completely resected without intraoperative complication. IHC staining was diffusely positive for ACTH (Fig. 2E), synaptophysin, and cytokeratin with decreased reticulin and an MIB-1 index of 3.3%. Prolactin, GH, TSH, LH, and FSH immunostaining were negative. Postoperative cortisol monitoring demonstrated decreased levels, with a nadir of 2.0 µg/dL on POD 0. Levels of ACTH and DHEA-S were decreased at 4.4 pg/mL (7.2–63.3 pg/mL) and 13.3 µg/dL (98.8–340 µg/dL), respectively, on POD 1. Prolactin remained within the normal range at 8.2 ng/mL (2.8–23.3 ng/mL). The patient was started on intravenous hydrocortisone 50 mg every 8 hours for adrenal insufficiency. Postoperative symptoms of nausea, headache, and muscle weakness resolved with hydrocortisone administration. She was discharged on hydrocortisone 60 mg daily in divided doses for adrenal insufficiency and had no signs of vasopressin deficiency during her 2-day hospital course.

By 3 months, the patient reported decreased fatigue, myalgia, and insomnia and improved overall well-being and physical appearance. She was weaned down to a total daily dose of 20 mg of hydrocortisone and had lost 5.2 kg. Her menstruation returned while having an etonogestrel implant. Rapid ACTH stimulation was abnormal, with decreased cortisol at 30 minutes of 4.1 µg/dL (7.2–63.3 pg/mL) demonstrating continued adrenal insufficiency. Follow-up MRI demonstrated miniscule remaining left pituitary adenoma (Fig. 3). Seven months after her second surgery, she was started on 50 µg levothyroxine for primary hypothyroidism in the setting of slightly elevated TSH of 4.1 µIU/mL (0.4–4.0 µIU/mL) and a low-normal T4 of 0.8 ng/dL (0.7–1.5 ng/dL).

FIG. 3
FIG. 3

Postoperative imaging 3 months after the second operation demonstrates near gross-total resection (yellow arrows: surgical cavity) of the left lateral pituitary adenoma on coronal precontrast (A) and postcontrast T1-weighted (B) and T2-weighted (C) MRI.

Two years after the second resection, the patient lost 10.1 kg (weight, 61.1 kg; BMI, 21.76 kg/m2). Her ACTH stimulation test became normal, and hydrocortisone therapy was discontinued. At the 2-year time point, the patient and her husband successfully conceived a child.

Patient Informed Consent

The necessary patient informed consent was obtained in this study.

Discussion

Double or multiple pituitary adenomas are discovered in 0.37%–2.6% of resected pituitary lesions.3,4,6,11,12 A majority of multiple pituitary adenomas are not suspected before surgery with an inconclusive clinical presentation or endocrine laboratory workup.6 The presentation of multiple synchronous neoplasms is thought to be more common than having a single neoplasm with multiple lineages.1 Studies have shown that additional pituitary adenomas are seen at a rate of 1.6%–3.3% in Cushing disease in studies including both contiguous and noncontiguous double pituitary adenomas.6 Additional pituitary adenomas that are hormonally active make up 40% of resected double pituitary adenomas, with most staining for gonadotroph adenoma.13 Overall, the most common incidental pituitary adenoma is prolactinoma,6 which occurs most frequently with GH or ACTH adenomas.5 In very rare instances, Cushing cases can present with hyperprolactinemia and Cushing synchronously.6 Hormonal secretion and clinical presentation are variable, with the pathology most often attributed to only one component of double pituitary adenoma.3,14 The multiple-hit theory is the most common hypothesis for double pituitary adenoma etiology with coincidental monoclonal expansion of two or more lineages, which present with separate pseudo-capsules for each lesion.15

Observations

On presenting with Cushing disease, the differential diagnosis before the initial operation considered that the known left lateral pituitary adenoma could be a mixed tumor with both prolactin and ACTH lineages. Therefore, it was the initial target of the resection until discovering the second adenoma intraoperatively. With two distinct adenomas, the inferomedial adenoma was presumed to be the source of the ACTH hypersecretion and was subsequently resected. The left lesion was thought to be a prolactinoma and hormonally inactive after historical dopaminergic therapy and thus was not pursued during the initial surgery. However, pathology confirmed that the opposite was true. Few cases have also involved incidental pituitary tumors that look like the hormonally active adenoma and encourage resection of it, leaving the primary pituitary adenoma behind.6,7 It has been reported that these “decoy lesions” can cause surgical failure and require secondary operations.6,7,10,16 Intraoperative localization and confirmation of the adenoma classification may have also been helpful during the case, including tissue-based ACTH antibody assay,9 plasma ACTH measurements with a immunochemiluminometric method,17 or intraoperative ultrasound.5,6

The inferomedial second tumor was not appreciated or reported throughout her serial MRI studies from 2010 to 2020. Interestingly, imaging did demonstrate the left pituitary adenoma that was medically treated as a prolactinoma, although it was later diagnosed as an ACTH-secreting lesion on IHC staining. Preoperative visualization of a pituitary adenoma in Cushing disease is reported to be limited, with a reported 50% incidence with negative MRI with standard 1.5 T.1,18,19 MRI technical refinements in magnet strength, slice thickness, or enhanced spin sequences have increased sensitivity, but one-third of patients with Cushing disease still have negative scans.20 Small prolactinomas, especially those near the cavernous sinus, are also notoriously difficult to visualize on MRI, although recent advances using co-registration of 11C-methionine positron emission tomography–computed tomography with MRI (Met-PET/MRICR) may prove useful.21 Difficulty with preoperative visualization complicates a diagnosis of multiple adenomas, with or without multiple endocrinopathies, and negatively affects surgical planning. In a single-institution retrospective review of MRI in all cases of double pituitary tumors, only one of eight patients (12.5%) over 16 years of age had a positive MRI for double pituitary tumors and was diagnosed preoperatively.2

The patient’s preoperative IPSS demonstrated a right central-to-peripheral gradient. This was incongruent with the MRI demonstrating the single left-sided tumor. While IPSS is useful in confirming Cushing disease, its sensitivity for lateralization has been reported at only 59%–71%.9 With this in mind and a known left-sided adenoma on MRI, exploration of the right side of the pituitary was not originally planned. Ultimately, the left-sided adenoma was the source of ACTH hypersecretion, which remains incongruent with preoperative IPSS. It has been suggested that multiple pituitary adenomas in Cushing disease could further decrease its accuracy.1,6

The patient’s initial historical prolactin levels (33.8 ng/dL) were lower than reported levels of 100–250 ng/dL for microadenoma and >250 ng/dL in cases of macroadenoma. Normally, in active single prolactinoma, prolactin secretion is correlated to size. We do not suspect that the presence of more than one pituitary adenoma would affect the level of prolactin hypersecretion.6 Slight elevations in prolactin can be attributed to causes such as pituitary stalk effect, medications, and physiological stimulation. During the 5 years of bromocriptine therapy, the effect on the inferomedial prolactinoma was unknown, as it was not appreciated on MRI. There are reports of prolactinomas being less responsive to dopaminergic agonist therapy in cases of double adenomas.14,22 Upon resection of the inferomedial prolactinoma during the initial operation, there was no further change in the patient’s prolactin levels, which could most likely be attributed to prior dopaminergic therapy. Unfortunately, the initial endocrine laboratory workup did not include levels of ACTH or cortisol. In addition to hyperprolactinemia, Cushing disease can also present with changes in menstruation. After the secondary resection and removal of the ACTH-secreting pituitary adenoma, the patient’s oligomenorrhea resolved and she achieved pregnancy. Retrospectively, it remains unclear if the prolactinoma was once truly active hormonally.

Lessons

The rare presence of two pituitary adenomas can complicate the diagnosis, medical and surgical management, and long-term outcomes for patients. A complete endocrine workup is essential when a pituitary adenoma is suspected and can help screen for pluri-hormonal and multiple pituitary adenomas. In our patient, it is unknown when the onset of hypercortisolism was with the limited initial hormonal workup.

Currently, localizing and resecting the hormonally active adenoma in double or multiple pituitary adenomas remain a challenge, with limitations in preoperative imaging and intraoperative measures. After encountering the additional inferomedial lesion during surgery, resection of both adenomas during the initial surgery may have been prudent to ensure the resolution of Cushing disease. Although exploration for additional pituitary adenomas is not usually recommended, it could be considered in cases of multiple pituitary adenomas and uncertainty of the culprit of Cushing disease.

The current characterization of pituitary tumors by the World Health Organization includes immunohistochemistry for both transcription factors and pituitary hormones, with clinical usefulness to be determined by future studies. Multiple lineages can occur mixed in a single pituitary adenoma or across different noncontiguous adenomas and can only be determined by TF immunostaining. The left ACTH-staining lesion in our patient had some shrinkage and MRI changes, which may have been a response to dopaminergic therapy. Full characterization of the tumor cell lineages in this case remains undetermined without staining for TFs.

In conclusion, we report a rare case of Cushing disease concurrent with a prolactinoma leading to the need for repeat resection. This is one of the few reported cases of a double pituitary adenoma leading to a lack of biochemical remission of hypercortisolism after the initial surgery. Strategies for localization of the active tumor in double pituitary adenomas are essential for primary surgical success and the resolution of endocrinopathies.

Author Contributions

Conception and design: Zwagerman, Tavakoli, Shah, Findling. Acquisition of data: Zwagerman, Armstrong, Tavakoli, Shah, Ioachimescu, Findling. Analysis and interpretation of data: Zwagerman, Armstrong, Tavakoli, Shah, Coss, Ioachimescu, Findling. Drafting of the article: Zwagerman, Armstrong, Shah. Critically revising the article: Zwagerman, Armstrong, Tavakoli, Shah, Ioachimescu, Findling. Reviewed submitted version of the manuscript: Zwagerman, Armstrong, Tavakoli, Shah, Laing, Ioachimescu, Findling. Approved the final version of the manuscript on behalf of all authors: Zwagerman. Statistical analysis: Armstrong, Shah. Administrative/technical/material support: Zwagerman, Armstrong, Shah. Study supervision: Zwagerman, Tavakoli, Shah, Laing.

References

Risk Comparison and Assessment Model of Deep Vein Thrombosis in Patients with Pituitary Adenomas After Surgery

Abstract

Background

Deep vein thrombosis (DVT), a major component of venous thromboembolism (VTE), is a common postoperative complication. Its occurrence after pituitary adenoma surgery is influenced by multiple factors.

Methods

This retrospective study analyzed 1440 pituitary adenoma cases treated at Beijing Tiantan Hospital (2018–2023). The incidence of postoperative DVT was recorded, and logistic regression was used to identify associated risk factors. Differences across pituitary adenoma subtypes were compared. Additionally, Regression and machine learning models were developed to predict DVT.

Results

Among 397 patients who underwent postoperative lower limb ultrasound, 104 (7.2 %) developed DVT. Significant risk factors included advanced age, higher body mass index (BMI), intravenous cannulation, prolonged hospital stay, shorter preoperative activated partial thromboplastin time (APTT), longer thrombin time (TT), elevated platelet count, and higher postoperative D-dimer levels. Patients with Cushing’s disease exhibited a significantly higher DVT incidence, potentially related to decreased pre- and postoperative APTT and PT/INR values. Conversely, patients with prolactin-secreting adenomas had a lower DVT incidence, possibly due to younger age and higher postoperative PT values. A support vector machine (SVM) model showed strong predictive performance (AUC: 0.82; accuracy: 86.08 %; specificity: 96.72 %).

Conclusion

DVT incidence varies by pituitary adenoma subtype. Machine learning enhances predictive models for postoperative DVT in pituitary adenoma patients.

Introduction

Venous thromboembolism (VTE), encompassing both deep vein thrombosis (DVT) and pulmonary embolism, is a common cardiovascular disorder. It typically presents with clinical symptoms such as lower limb swelling, chest pain, tachypnea, and, in severe cases, may result in fatal outcomes [1]. The development of VTE is influenced by three factors known as the Virchow triad: altered venous blood flow, endothelial or vessel wall damage, and hypercoagulability [2]. Surgical procedures can increase the risk of VTE, particularly DVT in the lower extremities, due to intraoperative injuries and postoperative hemodynamic changes [[3], [4], [5]]. In the absence of anticoagulant prophylaxis, the incidence of VTE following brain tumor surgery ranges from 3 % to 30 % [[6], [7], [8]]. Although pituitary adenomas are commonly considered benign cranial tumors, emerging evidence suggests that patients undergoing resection of pituitary adenomas may have a higher risk of postoperative VTE compared to those with other sellar or parasellar tumors such as craniopharyngiomas, meningiomas, or chordomas [9].
This disparity may be attributed to the unique hormone secretion functions of pituitary adenomas, as well as dysregulation of water and electrolyte balance—following surgery. Despite this, the risk factors contributing to the development of postoperative VTE in pituitary adenomas have not been extensively explored. Limited studies have identified a particularly elevated VTE risk in patients with Cushing’s disease, a hormone-secreting subtype of pituitary adenoma [10]. Given the relatively high incidence of postoperative DVT in this population, the present study aims to systematically investigate risk factors associated with lower extremity DVT after pituitary adenoma surgery. Furthermore, we seek to compare thrombotic risk across different clinical subtypes of pituitary adenomas and to construct a tailored risk prediction model to guide perioperative thromboprophylaxis in affected patients.

Changing face of Cushing’s Disease Over Three Decades in Pituitary Center

Abstract

Objective

Cushing Disease (CD) presents with typical clinical findings, even though, there is a wide spectrum of manifestations. Over the years, the sings and symptoms of Cushing’s syndrome (CS) have become more subtle and atypical forms of CS have emerged. In this study, we aimed to investigate the changes in the clinical presentation of CD in recent years.

Materials and methods

In this study, CD patients followed by our center were examined. A total of 258 patients with CD were included in the study. The clinical findings at the time of presentation, laboratory and imaging findings, treatment modalities and remission status in the first year after treatment were evaluated.

Results

The mean age of the patients included in the study was 41.3 ±13.28 years. CD patients diagnosed between 2013 and 2023 were older than those diagnosed between 1990 and 2012 (p < 0.001). There was no difference between the groups in terms of gender. Moon face, purple striae, hirsutism, and menstrual irregularities were statistically significantly less frequent in the last 10 years than in previous years (p < 0.001; p = 0.004; p < 0.001; p < 0.001, respectively). In addition, patients who applied after 2013 had lower baseline cortisol and adrenocorticotropic hormone (ACTH) levels, and a smaller median size of the pituitary adenoma. Limitations of the study include its retrospective design and the subjectivity of clinical data.

Conclusion

As the clinical presentation of Cushing’s disease changes over time, waiting for the typical Cushing’s clinic can delay diagnosis. It is important that clinicians take this into account when they suspect CD.

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