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

Damien C Weber,Patrick Meyer,Alessia Pica,Shahan Momjian,François P Pralong,Jean Guy Villemure

doi:10.1186/1748-717x-6-169

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.

Highlights

Pituitary adenomas are usually benign tumors that account for 10 - 15% of primary intracranial neoplasms [1]
The estimated 5-year tumor growth control was 95.5% after stereotactic fractionated RT (SFRT)
We examined the efficacy and toxicity of SFRT for Pituitary macroadenoma (PMA) in 27 patients with long term follow-up treated in an academic center

Summary

Introduction

Pituitary adenomas are usually benign tumors that account for 10 - 15% of primary intracranial neoplasms [1]. Tumor growth frequently causes compression of the visual apparatus, pituitary stalk, floor of the third ventricle and enlargement of the sella turcica[2,3]. Pituitary macroadenoma (PMA) refers to tumors more than 10 mm in diameter, this cutoff is not consensual [4]. Debulking surgery is beneficial in a RT can be delivered by conventional 3D-conformal delivery-techniques or newer radiation techniques, allowing for better target dose-conformation, including but not limited to intensity modulated RT[13], proton beam therapy[14], radiosurgery[15,16,17] or stereotactic fractionated RT (SFRT)[1,18,19]. We examined the efficacy and toxicity of SFRT for PMA in 27 patients with long term follow-up treated in an academic center

Methods

Results

Conclusion