Adjuvant or radical fractionated stereotactic radiotherapy for patients with pituitary functional and nonfunctional macroadenoma

Abstract

PurposeTo evaluate the efficacy and toxicity of stereotactic fractionated radiotherapy (SFRT) for patients with pituitary macroadenoma (PMA).Methods and MaterialsBetween March 2000 and March 2009, 27 patients (male to female ratio, 1.25) with PMA underwent SFRT (median dose, 50.4 Gy). Mean age of the patients was 56.5 years (range, 20.3 - 77.4). In all but one patient, SFRT was administered for salvage treatment after surgical resection (transphenoidal resection in 23, transphenoidal resection followed by craniotomy in 2 and multiple transphenoidal resections in another patient). In 10 (37%) patients, the PMAs were functional (3 ACTH-secreting, 3 prolactinomas, 2 growth hormone-secreting and 2 multiple hormone-secretion). Three (11.1%) and 9 (33.3%) patients had PMA abutting and compressing the optic chiasm, respectively. Mean tumor volume was 2.9 ± 4.6 cm3. Eighteen (66.7%) patients had hypopituitarism prior to SFRT. The mean follow-up period after SFRT was 72.4 ± 37.2 months.ResultsTumor size decreased for 6 (22.2%) patients and remained unchanged for 19 (70.4%) other patients. Two (7.4%) patients had tumor growth inside the prescribed treatment volume. The estimated 5-year tumor growth control was 95.5% after SFRT. Biochemical remission occurred in 3 (30%) patients with functional PMA. Two patients with normal anterior pituitary function before SFRT developed new deficits 25 and 65 months after treatment. The 5-year survival without new anterior pituitary deficit was thus 95.8%. Five patients with visual field defect had improved visual function and 1 patient with no visual defect prior to SFRT, but an optic chiasm abutting tumor, had a decline in visual function. The estimated 5-year vision and pituitary function preservation rates were 93.2% and 95.8%, respectively.ConclusionsSFRT is a safe and effective treatment for patients with PMA, although longer follow-up is needed to evaluate long-term outcomes. In this study, approximately 1 patient with visual field defect out of two had an improved visual function.

The Clinical Outcome of Hypofractionated Stereotactic Radiotherapy With CyberKnife Robotic Radiosurgery for Perioptic Pituitary Adenoma

“…Most series have demonstrated endocrine remission that varies widely between 5% and 63% 3,13-15 after SRS treatment and from 20% to 42% following FSRT technique. 8,16 The 54% hormonal normalization rate observed in this study is similar to hormonal normalization rates reported in other HSRT published studies 7,11,12 and also comparable with SRS and FSRT techniques. Nevertheless, comparing hormonal normalization between various fractionations including SRS, HSRT, or FSRT is difficult because of the retrospective nature, nonrandomized comparative study, difference in baseline characteristics such as tumor volume and pretreatment hormone levels, and difference in the definition of hormonal normalization.…”

Long term toxicity and prognostic factors of radiation therapy for secreting and non-secreting pituitary adenomas

“…Weber et al described 27 patients undergoing either adjuvant or radical RT for pituitary adenomas with a median follow-up of 6 years and found local control rates above 95% at 5 years [6]. Sun et al reported on 33 patients, in whom local control rates of 94% were achieved at 36 months [3].…”

“…It has been discussed controversially whether RT should be delivered after surgery, which is regarded as the preferential initial treatment. Additionally, substantial discussion has focussed on which risk factors can be identified arguing for early adjuvant treatment [4-6]. …”

Long-term Outcome After Fractionated Radiotherapy for Pituitary Adenoma

“…Multiple publications report excellent tumor control rates with RT for nonsecretory tumors, [3][4][5] but the prognosis for secretory tumors is less favorable. 4,[6][7][8][9] Major limitations of prior publications are that most series include patients without a tissue diagnosis or patients with no gross residual tumor at the time of RT, have short follow-up, and do not focus on the difference in outcome based on secretory status.…”