Mary Lee Vance
Mary Lee Vance
The diagnosis and treatment of a patient with a pituitary adenoma or another type of pituitary lesion requires a team approach involving the neurosurgeon, endocrinologist, primary care physician, and, in some patients, an ophthalmologist and radiation therapist. The diagnosis of excessive pituitary hormone secretion and/or loss of pituitary function is based on biochemical findings and can usually be confirmed by performing blood tests, except for patients with suspected Cushing syndrome. The primary treatment of pituitary adenomas is resection, except in patients with a prolactin-producing tumor, who are most successfully treated medically with a dopamine agonist. In this article the author reviews the principles of diagnosis and treatments and offers recommendations for ideal patient care.
Gautam U. Mehta, Jason P. Sheehan, and Mary Lee Vance
Nelson's syndrome (NS) is a significant and frequent risk for patients with Cushing's disease (CD) who undergo bilateral adrenalectomy. A recent study has shown tumor progression in 47% of patients at risk for NS. The authors sought to define the rate of NS in patients who were treated with Gamma Knife stereotactic radiosurgery (GK SRS) prior to bilateral adrenalectomy.
Consecutive patients with CD who were treated with GK SRS after pituitary surgery but before bilateral adrenalectomy were included. Serial MRI sequences were analyzed to evaluate for pituitary tumor growth. Clinical evaluations were performed to screen for NS. Follow-up for adrenocorticotropic hormone levels and hormone studies of other pituitary axes was performed.
Twenty consecutive patients were followed with neuroimaging and clinically for a median of 5.4 years (range 0.6–12 years). One patient (5%) developed pituitary tumor growth consistent with NS 9 months after adrenalectomy. By Kaplan-Meier analysis, progression-free survival was 94.7% at 1, 3, and 7 years. No predisposing factors were identified for the tumor progression. Two patients developed new pituitary dysfunction and no patient developed cranial neuropathy or visual deficit after GK SRS.
These findings suggest that GK SRS not only serves a role as second-line therapy for CD, but that it also provides prophylaxis for NS when used before bilateral adrenalectomy.
Jason P. Sheehan, Zhiyuan Xu, David J. Salvetti, Paul J. Schmitt, and Mary Lee Vance
Cushing's disease is a challenging neuroendocrine disorder. Although resection remains the primary treatment option for most patients, the disease persists if there is residual or recurrent tumor. Stereotactic radiosurgery has been used to treat patients with persistent Cushing's disease after a prior resection. The authors report on the long-term risks and benefits of radiosurgery for Cushing's disease.
A retrospective review of a prospectively collected database of radiosurgery patients was undertaken at the University of Virginia. All patients with Cushing's disease treated with Gamma Knife surgery (GKS) were identified. Those without at least 12 months of clinical and radiological follow-up were excluded from this analysis. Rates of endocrine remission, tumor control, and adverse events were assessed. Statistical methods were used to identify favorable and unfavorable prognostic factors.
Ninety-six patients with the required follow-up data were identified. The mean tumor margin dose was 22 Gy. The median follow-up was 48 months (range 12–209.8 months). At the last follow-up, remission of Cushing's disease occurred in 70% of patients. The median time to remission among all patients was 16.6 months (range 1–165.7 months). The median time to remission in those who had temporarily stopped taking ketoconazole at the time of GKS was 12.6 months, whereas it was 21.8 months in those who continued to receive ketoconazole (p < 0.012). Tumor control was achieved in 98% of patients. New loss of pituitary function occurred in 36% of patients. New or worsening cranial neuropathies developed in 5 patients after GKS, with the most common involving cranial nerves II and III.
Gamma Knife surgery offers a high rate of tumor control and a reasonable rate of endocrine remission in patients with Cushing's disease. The cessation of cortisol-lowering medications around the time of GKS appears to result in a more rapid rate of remission. Delayed hypopituitarism and endocrine recurrence develop in a minority of patients and underscore the need for long-term multidisciplinary follow-up.
Claudio De Tommasi, Mary Lee Vance, David O. Okonkwo, Alfa Diallo, and Edward R. Laws Jr.
Object. Adrenocorticotropic hormone (ACTH)—secreting pituitary macroadenomas are an uncommon cause of Cushing's disease (CD) and, subsequently, Nelson's syndrome (NS). They have been associated with low postoperative remission rates. The outcome of modern surgical treatment is unclear and thus was assessed in a series of 43 patients, with the goal of improving therapeutic results in patients with ACTH-secreting macroadenomas.
Methods. Thirty-seven patients presented with CD and six with NS. They represented 15% of the patients surgically treated at the authors' institution for ACTH-secreting adenomas. The median patient age was 38 years (range 14–71 years), and the mean duration of follow up was 37 months (range 1–108 months).
Remission occurred in 25 (67.6%) of 37 patients with CD, whereas the disease persisted in 12 (32.4%) of 37 patients. After an initial remission, three (12%) of 25 patients demonstrated signs and symptoms indicative of disease recurrence. Among patients with NS, only one (16.6%) displayed remission. Invasion of the dura mater by tumor was histologically demonstrated in 10 patients with CD and in two patients with NS.
Conclusions. Comprehensive management of CD caused by ACTH-secreting macroadenomas through the appropriate use of combination therapy, including surgery, radiotherapy, radiosurgery, and adrenalectomy, can lead to outcomes similar to those for microadenomas. Disease recurrence and persistence rates are higher, often because of the invasiveness associated with macroadenomas. Remission of NS-associated macroadenomas is difficult to achieve. Strategies for the characterization and treatment of invasive macroadenomas are needed.
Adomas Bunevicius, Darrah Sheehan, Mary Lee Vance, David Schlesinger, and Jason P. Sheehan
Stereotactic radiosurgery (SRS) is used for the management of residual or recurrent Cushing’s disease (CD). Increasing experience and technological advancements of Gamma Knife radiosurgery (GKRS) systems can impact the outcomes of CD patients. The authors evaluated the association of their center’s growing experience and the era in which GKRS was performed with treatment success and adverse events in patients with CD.
The authors studied consecutive patients with CD treated with GKRS at the University of Virginia since installation of the first Gamma Knife system in March 1989 through August 2019. They compared endocrine remission and complication rates between patients treated before 2000 (early cohort) and those who were treated in 2000 and later (contemporary cohort).
One hundred thirty-four patients with CD underwent GKRS during the study period: 55 patients (41%) comprised the early cohort, and 79 patients (59%) comprised the contemporary cohort. The contemporary cohort, compared with the early cohort, had a significantly greater treatment volume, radiation prescription dose, maximal dose to the optic chiasm, and number of isocenters, and they more often had cavernous sinus involvement. Endocrine remission rates were higher in the contemporary cohort when compared with the early cohort (82% vs 66%, respectively; p = 0.01). In a Cox regression analysis adjusted for demographic, clinical, and SRS characteristics, the contemporary GKRS cohort had a higher probability of endocrine remission than the early cohort (HR 1.987, 95% CI 1.234–3.199; p = 0.005). The tumor control rate, incidence of cranial nerve neuropathy, and new anterior pituitary deficiency were similar between the two groups.
Technological advancements over the years and growing center experience were important factors for improved endocrine remission rates in patients with CD. Technological aspects and results of contemporary Gamma Knife systems should be considered when counseling patients, planning treatment, and reporting treatment results. Studies exploring the learning curve for GKRS are warranted.