Predictors for secondary therapy after surgical resection of nonfunctioning pituitary adenomas

Factors determining recurrence of nonfunctioning pituitary adenomas (NFAs) that require further therapy are unclear as are postoperative follow-up imaging guidelines. We aimed to identify predictors for secondary therapy after surgical resection of NFAs and use this knowledge to inform postoperative management.A single-centre retrospective study of surgically resected NFAs in 108 patients followed for up to 15\ua0years. Serial tumour images were analysed for size, location and growth rate (GR) and tissue analysed for hormone cell type and proliferation indices with secondary treatment as outcome measure.Twenty-four of 66 (36%) patients harbouring a postoperative remnant required secondary treatment, all occurring within 10\ua0years. No secondary treatment was required in any of 42 patients with complete tumour resection. Age, gender, remnant volume and tumour histology were not different between patients requiring and not requiring secondary therapy. Remnant GRs in those requiring secondary therapy were more than 10-fold higher (