Assessing the association of tumor consistency and gland manipulation on hormonal outcomes and delayed hyponatremia in pituitary macroadenoma surgery

Abstract

BackgroundNeuro-endocrine dysfunction such as electrolyte imbalance and hypopituitarism are among the most frequent surgical complications following pituitary macroadenoma resection. In this study, we investigated the association between tumor consistency, intra-operative pituitary gland manipulation and post-operative pituitary dysfunction. MethodsA retrospective review was conducted on 84 consecutive patients who underwent endoscopic transsphenoidal surgery (eTSS) for pituitary macroadenoma between 2011 and 2018. Patient and tumor characteristics were obtained from chart abstraction and peri-operative imaging, and intra-operative video recordings of the eTSS were reviewed to visually assess tumor consistency and the degree of gland manipulation. ResultsThe rate of either delayed hyponatremia or new axis defect was 15.5% (13/84 patients). Variables associated with a higher rate of pituitary gland damage included 1) moderate to severe gland manipulation: RR = 5.14, 95% (confidence interval (CI) 2.07, 12.76), 2) a firm tumor consistency: RR = 6.75, (95% CI 3.23, 14.07); and 3) a larger tumor size: RR = 1.06, (95% CI 1.04, 1.09). ConclusionsIn the current series, the factors which were associated with an increased rate of iatrogenic pituitary injury were: increased manipulation of the gland intra-operatively, a firm tumor consistency not amenable to suction or curettage, and larger pituitary adenoma size. Recognition of the heterogeneity of macroadenoma consistency and growth patterns and appropriate usage of intra- and/or extra-capsular tumor resection techniques may help mitigate the risk of surgical pituitary injury.