Clinico-radio-pathological predictors of outcomes in patients with acromegaly undergoing endoscopic transsphenoidal surgery.

Abstract

Acromegaly is a rare chronic endocrine disorder with variable biochemical remission rates from 40% to 85%. Hence, understanding the factors predicting biochemical cures helps in planning targeted and personalized treatment. We aimed to study the various clinico-radio-pathological predictors of outcomes in patients with pituitary neuroendocrine tumor (PitNET) who underwent transsphenoidal surgery (TSS) at 3 months follow-up. Our cohort included 61 consecutive patients with acromegaly treated at an institute in northwest India between January 2019 and June 2021. The outcomes of TSS were assessed at the end of 3 months postoperatively as defined by Endocrine Society Guidelines 2014. The mean age at diagnosis was 38 ± 12 years, with the majority being females (67.2%). The median tumor volume was 2376 mm3 with high insulin-like growth factor-1 levels (3.12 ± 1.76 times the upper reference limit). Forty-two patients (68.8%) had radiological evidence of cavernous sinus invasion. Overall, the biochemical remission rate at 3 months was 34.4%. Unlike preoperative Knosp grading, T2-hypointensity was not predictive of biochemical remission. The granularity of PitNET, as well as immunohistochemical (IHC) markers such as Ki-67 index somatostatin receptor subtype (SSTR2/5) and low-molecular-weight cytokeratin (CAM5.2) expression, failed to show any significant correlation with remission. Overall, bulky tumors, higher hormone burden, and advanced Knosp grades translated to lower rates of biochemical remission in the present study cohort. Contrary to earlier studies, conventional IHC markers such as Ki-67, SSTR2/5, and CAM5.2 were not useful for predicting biochemical remission at 3 months.