June 20, 2025
Although generally benign, functioning pituitary adenomas can cause substantial and wide-ranging symptoms. Mayo Clinic's three main campuses have specialists with deep experience in treating these challenging tumors.
"Timely assessment and care at a high-volume center are always important for patients with functioning pituitary adenomas. Mayo Clinic is committed to providing an opinion within 48 hours," says Gelareh Zadeh, M.D., Ph.D., chair of Neurosurgery at Mayo Clinic in Rochester, Minnesota.
Mayo Clinic is one of the largest pituitary centers in the United States. Every year, specialists evaluate and treat more than 2,600 people with pituitary tumors, including patients seeking revision surgery after initial treatment elsewhere.
A multidisciplinary approach facilitates comprehensive evaluation of tumors, associated hormonal dysregulation and treatment options. "Optimal care requires a number of subspecialists, including expert endocrinologists. It's really important to have that team in place," says Susan L. Samson, M.D., Ph.D., an endocrinologist at Mayo Clinic in Jacksonville, Florida, and chair of Endocrinology, Diabetes and Metabolism.
"That collaborative approach is a unique care model offered only at Mayo Clinic, to achieve the best experiences and outcomes for patients with a wide range of pituitary tumors," Dr Zadeh says.
Treatment is tailored to individual patients. "No two patients are alike. No two pituitary tumors are alike," says Chandan Krishna, M.D., a neurosurgeon at Mayo Clinic in Phoenix/Scottsdale, Arizona. "Expertise in the full range of treatment approaches goes a long way toward providing the best outcomes."
When indicated, surgery often is challenging, regardless of tumor size. "These are very delicate, complicated surgeries," says Jamie J. Van Gompel, M.D., a neurosurgeon at Mayo Clinic's campus in Minnesota. "It takes an experienced surgeon to explore the gland without damaging it and to achieve maximal resection. We want to give patients a high chance of cure."
Finding and resecting tumors
Corticotroph adenoma
Photon-counting-detector CT shows coronal (left) and axial (right) views of a corticotroph adenoma.
Functioning pituitary tumors — particularly corticotroph adenomas — often are too small to be clearly visible on standard MRI. To overcome that challenge, Mayo Clinic uses several new technologies, including 7T MRI and photon-counting-detector CT, which directly counts each X-ray photon to characterize its energy. The result is ultrahigh spatial resolution and fewer artifacts.
"Other emerging technologies — including positron emission tomography (PET) using tracers such as 11C-methionine and 18F-FET — have also shown promising results in the evaluation of MRI-occult primary or recurrent pituitary adenomas," says Neetu Soni, M.B.B.S., M.D., a neuroradiologist at Mayo Clinic's campus in Florida. Researchers there are planning a study of 18F-FET PET imaging in MRI-occult functional pituitary adenomas.
"Understanding the exact tumor location helps us determine the risks of surgery and provide targeted treatment," Dr. Van Gompel says. "It also improves the chances of long-term cure." Newer surgical techniques, such as pseudocapsule-based resection, also can reduce the likelihood of recurrence.
"Mayo Clinic is committed to providing an opinion within 48 hours."
Transnasal transsphenoidal surgery remains standard practice for pituitary adenoma resections. Mayo Clinic was among the first institutions to research the procedure and routinely includes ENT-head and neck surgeons on the surgical team.
"Our ENT surgery colleagues have become an indispensable part of our pituitary care team. Their immense knowledge of the nasal cavity and expertise in mucosal flap for reconstruction of the skull base defect is extremely important," Dr. Krishna says.
An interdisciplinary perioperative protocol helps minimize surgery-related complications. As described in the October 2024 issue of World Neurosurgery, the protocol also can shorten the length of hospital stays.
"We have forged new ground in perioperative care," Dr. Samson says. "Our protocol helps determine whether a patient requires corticosteroids in the operating room or is at high risk for arginine vasopressin deficiency or hyponatremia and requires fluid restrictions. The goal is to improve quality and patient satisfaction while reducing length of stay and complications."
Mayo Clinic researchers also are finding ways to predict pituitary surgery outcomes. They helped develop an easy-to-use scoring system to identify patients with growth hormone-secreting pituitary adenomas who have the highest chances of long-term biochemical remission. They described the scoring system in the February 2024 issue of World Neurosurgery. Research published in the March 2025 issue of Journal of Neurosurgery explained Mayo Clinic's development of a machine learning algorithm to predict long-term endocrinological remission in Cushing disease.
"Identifying these patients would be useful to help set patient and physician expectations and to prepare for possible adjuvant treatment in the future," Dr. Van Gompel says.
Cutting-edge medical management
Medical therapy is generally the first line treatment for prolactinomas. Patients with other types of functioning pituitary adenomas also might have medical treatment if their tumors can't be completely resected.
"We have years of experience with therapies that both shrink tumors and treat hormonal abnormalities," says Dr. Samson, who has helped author international consensus statements regarding management of patients with prolactinomas and acromegaly. "Our clinician-researchers have also been involved in seminal clinical trials for some of the new medications that are available. Having more experience with some of these lesser used drugs is really important."
"We have forged new ground in perioperative care."
One example is oral octreotide capsules for the treatment of acromegaly. Until recently, only injectable forms of the drug were available. As noted in the June 2024 issue of Expert Review of Endocrinology & Metabolism, Mayo Clinic researchers recommend wider adoption of the oral medication. "It has been associated with improved patient-reported quality of life measures compared with those reported for the injectable medications," Dr. Samson says.
Throughout the care process, Mayo Clinic specialists work with patients' local clinicians to provide treatment and follow-up monitoring. "We know that high-volume pituitary centers have improved outcomes, especially with functioning tumors," Dr. Samson says. "Our work with referring clinicians is a partnership. Open communication is available at any time."
For more information
Sanchez-Garavito JE, et al. Implementation of a standardized interdisciplinary perioperative protocol for patients undergoing transsphenoidal surgery: Impact on patients outcomes. World Neurosurgery. 2024;190:e331.
Cohen-Cohen S, et al. A novel preoperative score to predict long-term biochemical remission in patients with growth-hormone secreting pituitary adenomas. World Neurosurgery. 2024;182:e882.
Shinya Y, et al. Machine learning-based model to predict long-term tumor control and additional interventions following pituitary surgery for Cushing's disease. Journal of Neurosurgery. In press.
Fleseriu M, et al. Oral octreotide capsules for acromegaly treatment: Application of clinical trial insights to real-world use. Expert Review of Endocrinology & Metabolism. 2024;19:367.
Refer a patient to Mayo Clinic.