Endoscopic Endonasal Transtuberculum Transplanum Approach for Resection of Giant Pituitary Adenoma: The Second Floor Strategy to Avoid Postoperative Pituitary Apoplexy

Giant pituitary adenomas (GPAs) have widely been defined as those tumors with a maximum diameter of >4 cm and represent 5 to 20% of pituitary tumors. These lesions are typically removed surgically unless identified as a prolactinoma, however, pituitary apoplexy is a rare and fatal complication that can sometimes ensue during the perioperative or postoperative period. Over the years, authors have noticed that during endoscopic endonasal approach (EEA) for resection of a GPA, using the traditional approach of starting the removal of tumor from the floor of the sella and then going progressing superiorly causes the tumor to suffer intraoperative apoplexy. We suspect that the partial resection of giant pituitary adenomas causes venous stasis in the residual tumor leading to tumor venous infarct and hemorrhagic transformation. This is likely because the traditional strategy of removing the lower part of the tumor initially when coming from a transsphenoidal approach leads to early disconnection of the suprasellar component in relation to the venous drainage that was established to the cavernous sinus. Consequently, the suprasellar tumor becomes quickly and progressively firmer making a complete resection less favorable and more likely to be associated with residual tumor postoperative apoplexy, deficits and possibly death.