For Pituitary Tumors, Gamma Knife™ Radiosurgery Offers Better Tumor Control

For many patients with pituitary tumors, initial surgical intervention is followed quickly by Gamma Knife™ radiosurgery. The benefits of using this radiosurgical intervention are many, and can offer better tumor control and a more positive long-term prognosis compared to surgery alone.

San Diego, CA (PRWEB) July 03, 2017

Worldwide, up to 20% of all brain tumors—those confined within the skull—are identified as pituitary adenomas.(1) Each year, almost 10,000 new pituitary tumors are diagnosed in the United States alone, with the vast majority of these tumors being pituitary adenomas. As efforts to improve treatment for patients with pituitary tumors continue, researchers are discovering just how powerful treatment with Gamma Knife™ radiosurgery can be, at facilities like the San Diego Gamma Knife Center® (SDGKC).

Recent studies have shown compelling results for patients who received treatment with Gamma Knife™ radiosurgery following traditional surgery for pituitary tumor removal. Overall, tumor control was achieved with Gamma Knife™ treatment in up to 94% of patients studied.(1) For up to 85% of these patients, tumor control was still achieved 10 years after treatment with the Gamma Knife™.(6)

Pituitary adenomas are typically benign, but they can still cause significant problems for patients due to their location in the brain.(3) Many of these tumors also secrete certain hormones, which can ultimately change the way patients’ bodies function.(3) In most cases, the first line of defense in dealing with pituitary tumors involves surgical removal of as much of the tumor as possible; however, residual tumor tissue can exist in the brain after this process.(4)

Even though many physicians choose surgery as an initial treatment, Gamma Knife™ radiosurgery can be either a primary or secondary choice for the management of pituitary tumors. Most often, Gamma Knife is used as a secondary treatment following surgery.(5) A growing number of studies show that treating patients with the Gamma Knife™ after surgical removal of pituitary tumors is extremely beneficial for patients and can dramatically improve their long-term tumor control results.

Dr. Kenneth Ott, neurosurgeon of SDGKC®, said, “The extreme accuracy of Gamma Knife radiosurgery allows effective treatment of residual pituitary tumors following surgery to remove much of the tumor volume. In my practice, residual tumors which I have operated on are treated with Gamma Knife radiosurgery which almost always stops further growth.”

Dr. Ott continued to explain that Gamma Knife radiosurgery is more effective than prior external beam methods of radiation and avoids complications to near-by sensitive structures. Tumors within a few millimeters of the optic nerves can be safely treated because of the frame-based fixation and software advantages of Gamma Knife. Tumors which are slowly growing can also be effectively treated without the need for surgery, as long as there is no visual loss from tumor compression of the optic nerves.

Patient outcomes can also be influenced by how soon after brain surgery they receive treatment with the Gamma Knife™. In many cases, patients benefit the most from early intervention with radiosurgery; some studies have suggested that patients who receive Gamma Knife treatment more than six months after their initial surgery are at a significantly greater risk of pituitary tumor progression nearly six years post-surgery.(7)

“Pituitary tumors, in general should be treated before the tumor compresses the overlying optic nerves,” said Dr. Ott. “The earlier the treatment begins, the better. The final decision regarding Gamma Knife should be made on a case-by-case basis by a surgeon who is experienced in surgery and radiosurgery.”
About San Diego Gamma Knife Center:
Since its opening, the San Diego Gamma Knife Center® has treated over 4,000 patients with various brain disorders from around the world. The facility is equipped to provide advanced radiosurgical treatment for a variety of conditions, including metastatic brain tumors, primary brain tumors, arteriovenous malformations, and functional disorders such as trigeminal neuralgia and cluster headaches.

On the campus of Scripps Memorial Hospital, the Center offers the use of its facilities to some of the top neurosurgeons and radiation oncologists in Southern California. It’s also a proud partner of the Neurosciences Department of Scripps Memorial Hospital La Jolla, helping to provide accurate diagnoses, treatment and support for a range of neurological conditions and disorders. To learn more about the San Diego Gamma Knife Center®, please visit http://www.sdgkc.com.

Sources:
1.    Sheehan J, et al. Gamma Knife radiosurgery for the management of nonfunctioning pituitary adenomas: A multicenter study. Journal of Neurosurgery. 2013;119:446. http://thejns.org/doi/full/10.3171/2013.3.JNS12766. Accessed June 20, 2017.
2.    What Are the Key Statistics About Pituitary Tumors? American Cancer Society. https://www.cancer.org/cancer/pituitary-tumors/about/key-statistics.html. Accessed June 20, 2017.
3.    What Are Pituitary Tumors? American Cancer Society. https://www.cancer.org/cancer/pituitary-tumors/about/what-is-pituitary-tumor.html. Accessed June 20, 2017.
4.    Radiation—Gamma Knife Radiosurgery for Pituitary Adenomas. Pituitary Network Association. https://pituitary.org/medical-resources/pavilions/diagnostics-scanning-and-radiological-pavilion/diagnostics-scanning-and-radiological-archive/radiation-gamma-knife-radiosurgery-for-pituitary-adenomas. Accessed June 20, 2017.
5.    Gamma Knife Radiation Therapy for Pituitary Tumors—Candidates for Gamma Knife Treatment. The Pituitary Society. http://pituitarysociety.org/patient-education/pituitary-disorders/gammaradiation/candidates. Accessed June 20, 2017.
6.    Lee C, et al. Initial Gamma Knife radiosurgery for nonfunctioning pituitary adenomas. Journal of Neurosurgery. 2014;120:647. http://thejns.org/doi/full/10.3171/2013.11.JNS131757. Accessed June 20, 2017.
7.    Gamma Knife Radiosurgery Safe in Early Pituitary Tumor. Medscape. http://www.medscape.com/viewarticle/879250. Accessed June 20, 2017.

For the original version on PRWeb visit: http://www.prweb.com/releases/2017/07/prweb14478413.htm

Endoscopic Surgery on a Pituitary Adenoma

Philip Theodosopoulos, M.D. is Professor and Vice-Chair of Neurological Surgery at the University of California, San Francisco. He is the Director of the Skull Base Tumor Program and has extensive experience performing endoscopic transsphenoidal pituitary surgery for pituitary tumors (over 1000 operations) and other disease processes as well as tumors of the base of the skull.

In this video Dr. Theodosopoulos illustrates portions of an endoscopic resection of a pituitary adenoma.

 

To learn more about Dr. Theodosopoulos and to schedule an appointment for consultation please copy this link:
neurosurgery.UCSF.edu/index.php/about_us_faculty_theodosopoulos.html

Imaging Technique Measures Tumor Stiffness to Aid Surgical Planning

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Important steps in planning tumor surgery include identifying borders between tumor and healthy tissue and assessing the tumor stiffness, e.g. hard and calcified or soft and pliant. For decades, tumors near the surface of the body have been evaluated for stiffness by simple palpation—the physician pressing on the tissue. Because tumors within the skull cannot be palpated, researchers used Magnetic Resonance Elastography (MRE) to assess pituitary tumor stiffness by measuring waves transmitted through the skull into pituitary macroadenomas (PMAs). MRE reliably identified tumors that were soft enough for removal with a minimally-invasive suction technique versus harder tumors requiring more invasive surgery.

“The group developed brain MRE several years ago and is now successfully applying it to clinical diagnosis and treatment,” explained Guoying Liu, Ph.D., Director of the NIBIB Program in Magnetic Resonance Imaging. “This development of a new imaging technique followed by its practical application in surgical planning for better patient outcomes is an outstanding example of one of the main objectives of NIBIB-funded research.”

MRE is a special magnetic resonance imaging technique that captures snapshots of shear waves that move through the tissue and create elastograms—images that show tissue stiffness. John Huston III, M.D., Professor of Radiology at the Mayo Clinic in Rochester, MN, and senior author of the study, explains how MRE works. “MRE is similar to a drop of water hitting a still pond to create the ripples that move out in all directions. We generate tiny, harmless ripples, or shear waves, that travel through the brain of the patient. Our instruments measure how the ripples change as they move through the brain and those changes give us an extremely accurate measure–and a color-coded picture–of the stiffness of the tissue.”

MRE data enables non-invasive surgical planning

Ninety percent of PMAs are soft—nearly the consistency of toothpaste. Therefore, without MRE, surgeons would routinely plan for a procedure called transphenoidal resection that employs very thin instruments that are threaded through the nasal cavity to the pituitary gland at the base of the skull, where suction is used to remove the tumor. However, in about 10% of the cases, the surgeon will encounter a hard tumor. At that point an attempt is made to break-up the tumor—essentially chipping away at it with sharp instruments. If that is not successful, the surgeon must perform a fully-invasive craniotomy that involves removing a piece of the skull bone in order to fully expose the tumor.

The more extensive procedure means added risk and discomfort for patients, and up to a week-long recovery in the hospital compared to the transphenoidal approach that allows patients to leave the hospital in a day or two. Using MRE, hard PMAs can be identified and the more extensive craniotomy can be planned before starting the surgery, which makes the more invasive procedure less taxing for both the surgeon and patient. Similarly, MRE showing a soft PMA gives surgeons confidence that the nasal entry and removal by suction will be successful-eliminating the likelihood that the surgeon may need to perform a second fully-invasive craniotomy.

In the study of PMA reported in the January 2016 issue of the journal Pituitary, the group performed pre-surgical MRE evaluation of the PMAs of 10 patients.The MRE measurements were compared to tumor classifications made by inspection of the tumor during surgery. The surgeons categorized six tumors as soft and four tumors as medium. No tumors were deemed to be hard. The comparison of the MRE results and reports of stiffness by the surgeons when the tumor was removed and inspected were in close agreement, which was confirmed by statistical analysis.

Future plans

Although brain MRE is not yet widely available, Huston explained that the surgeons at the Mayo Clinic are now routinely using MRE to plan the best procedure for the removal of PMAs as well as several other types of brain tumor. And, even though this study of the 10 PMA patients is a very small set, Huston believes that as Mayo surgeons continue to use MRE in planning, the technique will likely begin to be adopted by other surgical centers.

Huston explained that an important aspect of some of the other brain tumor types, which the surgeons are finding extremely useful, is the ability of MRE to identify tumor adhesion to the brain. Adhesion refers to whether the brain tumor and healthy brain tissue are connected by an extensive network of blood vessels and connective tissue. This is in comparison with a tumor that is in the brain but is isolated from healthy tissue.

When MRE is used to analyze this aspect of the tumor, it clearly identifies those that are non-adhered, showing a border around the tumor through which there are no vascular connections. Conversely, MRE of adhered tumors show no border between the tumor and healthy brain, indicating extensive vascular and soft tissue connections between brain and tumor. Mutual blood vessels make removal of adherent tumors much more difficult, with a much higher chance of damage to healthy tissue and potential loss of function for the patient.

Huston and his colleagues are continuing to apply MRE, often called “palpating by imaging” to diagnosis of other brain disorders. In addition to characterizing focal brain disorders such as tumors, the group is testing the potential for MRE to provide diagnostic information about diffuse brain disease, and are currently using MRE brain stiffness patterns to identify different types of neural disorders including dementia.

This research was funded by the National Institutes of Health through the National Institute of Biomedical Imaging and Bioengineering grant EB001981.

Magnetic resonance elastography detects tumoral consistency in pituitary macroadenomas. Hughes JD, Fattahi N, Van Gompel J, Arani A, Ehman R, Huston J 3rd. Pituitary. 2016 Jun;19(3):286-92

From http://www.rdmag.com/news/2017/01/imaging-technique-measures-tumor-stiffness-aid-surgical-planning

UAE Patient’s (Pituitary) Brain Tumour Removed Through Nostrils

Dubai: A 34-year-old patient working as a crane operator has undergone a remarkable new procedure of surgery at Thumbay Hospital, Dubai, that facilitated the removal of a brain tumour through the nostrils.

The patient, Mehnaj Khan, a Pakistani crane operator, underwent endoscopic trans-nasal trans-sphenoidal surgery in September, where the tumour was removed through the nose by endoscopic surgery without any cut or stitches on the skin. The father of five children has now made a full recovery, with improved vision, a hospital spokesperson said.

Khan first noticed something was wrong when his eyesight began to diminish, first the right eye, followed by the left eye. Although he had ignored his frequent bouts of headache for two years, Khan was compelled to visit an ophthalmologist due to vision deterioration. When an eye check-up revealed nothing was wrong, he was referred to to Thumbay Hospital, where an MRI scan of the brain revealed that he had a large tumour in the pituitary gland, pressing on the optic apparatus of brain and also hypothalamus, a very vital part of brain. This tumour was pressing on his optic nerves, causing him to slowly lose his sight.

Dr. Ishwar Chandra Premsagar, consultant neurosurgeon at Thumbay Hospital who operated on Khan, said: “Conventionally, such operations require surgeons to open the skull — a procedure known as a craniotomy. Alternatively, affected portions of the brain are reached via major incisions in the side of the face or inside the mouth, leaving behind major scars of the surgery. However, the patient’s tumour was removed by suctioning it out through his nose.”

An ear nose and throat (ENT) surgeon and an eye surgeon were consulted to plan the surgery and save further deterioration of vision while providing a chance for complete recovery.

Khan, who was nearly blind in one eye with the tumour growth, expressed his gratitude to the hospital and the teams of surgeons as he noticed improvement in his vision after the surgery. By the end of the week, he could read too. The patient was very thankful to the team of surgeons.

Dr Premsagar added: “The endoscope provides a close-up view of the pituitary, allowing the surgeon to remove the entire tumour out in one go through the nostrils, causing no disfigurement or damage to the brain. On the other hand, the procedure ensures far less danger of brain damage or stroke, and the patient usually makes a quicker recovery. Although post-surgery, deterioration of vision stops, but one cannot guarantee complete recovery of vision. This patient was lucky as his vision improved, but it may not happen in all patients. Hence, it is extremely important that one should ensure early consultation, diagnosis and surgery to ensure high chances of recovery.”

From http://gulfnews.com/news/uae/health/uae-patient-s-brain-tumour-removed-through-nostrils-1.1933841

Experimental Drug Improves Cushing’s Disease

International phase 3 trial is largest study ever of rare endocrine disorder

A new investigational drug significantly reduced urinary cortisol levels and improved symptoms of Cushing’s disease in the largest clinical study of this endocrine disorder ever conducted.

Results of the clinical trial conducted at centers on four continents appear in the March 8 issue of the New England Journal of Medicine and show that treatment with pasireotide cut cortisol secretion an average of 50 percent and returned some patients’ levels to normal.

“Cushing’s disease is a rare disorder, with three to five cases per million people. It can affect all ages and both genders but is most common in otherwise healthy young women,” says Harvard Medical School Professor of Medicine Beverly M.K. Biller of the Massachusetts General Hospital (MGH) Neuroendocrine Unit, senior author of the study.

“Often misdiagnosed, Cushing’s is associated with a broad range of health problems – causing physical changes, metabolic abnormalities, and emotional difficulties – and if not controlled, significantly increases patients’ risk of dying much younger than expected,” Biller says.

Cushing’s disease, one of several conditions that lead to Cushing’s syndrome, is characterized by chronically elevated secretion of the hormone cortisol. The disease is caused by a benign pituitary tumor that oversecretes the hormone ACTH, which in turn induces increased cortisol secretion by the adrenal glands.

Symptoms of Cushing’s syndrome include weight gain, hypertension, mood swings, irregular or absent periods, abnormalities of glucose processing (insulin resistance, glucose intolerance, and type 2 diabetes), and cardiovascular disease. Because those symptoms are associated with many health problems, physicians may not consider the rare possibility of Cushing’s. The diagnosis can be difficult to make and usually requires the expertise of an endocrinologist. Because cortisol levels normally fluctuate during the day, a single blood test is unlikely to identify chronic elevation, and thus the most common diagnostic test measures a patient’s 24-hour urinary output.

First-line treatment for Cushing’s disease is surgical removal of the ACTH-secreting tumor, which leads to remission in 65 to 90 percent of patients. But symptoms return in 10 to 30 percent of those patients, requiring repeat surgery, radiation therapy, or treatment with drugs that interfere with part of the cortisol control system. Until last month, there was no specific FDA-approved medical treatment for Cushing’s syndrome; the newly approved drug mifepristone should benefit some patients, but it does not affect the pituitary source of the condition or reduce cortisol levels.

The current phase 3 trial of pasireotide — the first drug that blocks ACTH secretion by binding to somatostatin receptors on the pituitary tumor — was sponsored by Novartis Pharma. The trial enrolled 162 patients at 62 sites in 18 countries. Nearly 85 percent of participants had either persistent disease that had not responded to surgery or had recurrent disease; the other 15 percent were recently diagnosed but not appropriate candidates for surgery.

Participants were randomly assigned to two groups, one starting at two daily 600-microgram injections of pasireotide and the other receiving 900-microgram doses. Three months into the 12-month trial, participants whose urinary cortisol levels remained more than twice the normal range had their dosage levels increased. During the rest of the trial, dosage could be further increased, if necessary, or reduced if side effects occurred.

At the end of the study period, many patients had a significant decrease in their urinary cortisol levels, with 33 achieving levels within normal range at their original dosage by month six of the trial. Participants whose baseline levels were less than five times the upper limit of normal were more likely to achieve normal levels than those with higher baseline levels, and the average urinary cortisol decrease across all participants was approximately 50 percent. Many Cushing’s disease symptoms decreased, and it became apparent within the first two months whether or not an individual was going to respond to pasireotide.

Transient gastrointestinal discomfort, known to be associated with medications in the same family as pasireotide, was an expected side effect. Another side effect was elevated glucose levels in 73 percent of participants, something not seen to the same extent with other medications in this family. These elevated levels will require close attention, because many Cushing’s patients already have trouble metabolizing glucose. Biller explains, “Those patients who already were diabetic had the greatest increases in blood sugar, and those who were pre-diabetic were more likely to become diabetic than those who began with normal blood sugar. However, elevations were even seen in those who started at normal glucose levels, so this is real and needs to be monitored carefully.”

Additional trials of pasireotide are in the works, and a phase 3 study of a long-acting version of the drug was recently announced. Biller notes that the potential addition of pasireotide to available medical treatments for Cushing’s disease would have a number of advantages. “It’s very important to have medications that work at different parts of the cortisol control system – which is the case for the currently used medications that work at the adrenal gland level; pasireotide, which works at the pituitary gland; and mifepristone, which blocks the action of cortisol at receptors in the body. Having more options that work in different ways is valuable because not all patients respond to one medicine and some may be unable to tolerate a specific drug’s side effects.

“As we have more drugs available to treat Cushing’s,” Biller adds, “I think in the long run we may start using combinations of drugs, which is the approach we use in some patients with acromegaly, another disorder in which a pituitary tumor causes excess hormone secretion. Ultimately, we hope to be able to give lower doses leading to fewer overall side effects, but that remains to be determined by future studies.”

Annamaria Colao, University of Naples, Italy, is the lead author of the report. Additional co-authors are Stephan Petersenn, University of Duisberg-Essen, Germany; John Newell-Price, University of Sheffield, U.K.; James Findling, Medical College of Wisconsin, Milwaukee; Feng Gu, Peking Union Medical College Hospital, Beijing; Mario Maldonado, Ulrike Schoenherr, and David Mills, Novartis Pharma; and Luiz Roberto Salgado, University of São Paulo Medical School, Brazil.

From http://dailyrecords.us/experimental-drug-improves-cushings-disease/

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