skip to main content

SciTech ConnectSciTech Connect

Title: Outcomes of Proton Therapy for Patients With Functional Pituitary Adenomas

Purpose/Objective(s): This study evaluated the efficacy and toxicity of proton therapy for functional pituitary adenomas (FPAs). Methods and Materials: We analyzed 165 patients with FPAs who were treated at a single institution with proton therapy between 1992 and 2012 and had at least 6 months of follow-up. All but 3 patients underwent prior resection, and 14 received prior photon irradiation. Proton stereotactic radiosurgery was used for 92% of patients, with a median dose of 20 Gy(RBE). The remainder received fractionated stereotactic proton therapy. Time to biochemical complete response (CR, defined as ≥3 months of normal laboratory values with no medical treatment), local control, and adverse effects are reported. Results: With a median follow-up time of 4.3 years (range, 0.5-20.6 years) for 144 evaluable patients, the actuarial 3-year CR rate and the median time to CR were 54% and 32 months among 74 patients with Cushing disease (CD), 63% and 27 months among 8 patients with Nelson syndrome (NS), 26% and 62 months among 50 patients with acromegaly, and 22% and 60 months among 9 patients with prolactinomas, respectively. One of 3 patients with thyroid stimulating hormone—secreting tumors achieved CR. Actuarial time to CR was significantly shorter for corticotroph FPAs (CD/NS) compared with other subtypes (P=.001). At a median imagingmore » follow-up time of 43 months, tumor control was 98% among 140 patients. The actuarial 3-year and 5-year rates of development of new hypopituitarism were 45% and 62%, and the median time to deficiency was 40 months. Larger radiosurgery target volume as a continuous variable was a significant predictor of hypopituitarism (adjusted hazard ratio 1.3, P=.004). Four patients had new-onset postradiosurgery seizures suspected to be related to generously defined target volumes. There were no radiation-induced tumors. Conclusions: Proton irradiation is an effective treatment for FPAs, and hypopituitarism remains the primary adverse effect.« less
Authors:
;  [1] ;  [2] ;  [3] ; ;  [4] ;  [3] ; ;  [5] ;  [3] ;  [3]
  1. Harvard Radiation Oncology Program, Boston, Massachusetts (United States)
  2. Tufts University School of Medicine, Boston, Massachusetts (United States)
  3. Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)
  4. Neuroendocrine Unit, Massachusetts General Hospital, Boston, Massachusetts (United States)
  5. Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts (United States)
Publication Date:
OSTI Identifier:
22420437
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Radiation Oncology, Biology and Physics; Journal Volume: 90; Journal Issue: 3; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; ACROMEGALY; ADENOMAS; BIOMEDICAL RADIOGRAPHY; COMPARATIVE EVALUATIONS; HAZARDS; PATIENTS; PROTON BEAMS; RADIATION DOSES; RADIOTHERAPY; RBE; SURGERY; TOXICITY; TSH