Beyond Gross Total and Subtotal: Does Volumetric Resection Matter in Nonfunctioning Pituitary Macroadenomas?

Area of Science:

• Neurosurgery
• Oncology
• Radiology

Background:

• Pituitary macroadenoma (PMA) recurrence is a clinical concern.
• Volumetric assessment of resection degree in PMA has not been previously studied.
• This study focuses on nonfunctioning PMA measuring ≥2 cm.

Purpose of the Study:

• To investigate the impact of volumetric tumor resection on predicting recurrence and retreatment in pituitary macroadenoma.
• To determine the relationship between extent of resection (EOR) and tumor regrowth.

Main Methods:

• Retrospective review of 78 patients with surgically resected nonfunctioning PMA (≥2 cm) from 1998-2008.
• Volumetric quantification of preoperative and postoperative tumor size by a neuroradiologist.
• Calculation of EOR and analysis of recurrence and retreatment rates over a median follow-up of 113 months.

Main Results:

• Tumor recurrence was observed in 47% of patients within a median of 55 months.
• Univariate and multivariate analyses identified younger age and higher EOR as significant predictors of decreased recurrence.
• An EOR <86% was associated with increased PMA regrowth, with significant differences noted in Kaplan-Meier analysis.

Conclusions:

• Younger age and a higher extent of resection (EOR) are significant predictors of reduced pituitary macroadenoma regrowth and need for retreatment.
• Volumetric EOR assessment is a valuable tool for predicting outcomes in large pituitary macroadenomas.
• Further research with larger cohorts and volumetric analysis is warranted.