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.

We hypothesize that by accessing the tumor from the suprasellar portion first via a transplanum transtuberculum approach, and then resecting the inferior sellar portion via a transsellar approach secondarily allows the surgeon to completely remove the lesion without subsequent pituitary apoplexy.

We re-examined three cases at our home institution of The Ohio State University Wexner Medical Center to illustrate the problems with the traditional endoscopic endonasal transsellar approach in contrast to our newly proposed surgical method.

Case 1: A 62-year-old male experienced partial GPA resection using an endoscopic endonasal transsellar approach. A component of the tumor lateral to the right optic nerve was left for posterior treatment, which led to apoplexy of the residual tumor and vision deterioration. The patient was taken back and a craniotomy was performed to remove the enlarged residual. The patient ultimately recovered but lost vision in his right eye due to the apoplexy.

Case 2: A 46-year-old male underwent partial resection of a GPA via endoscopic endonasal transsellar approach at an outside institution first, which led to a long and complicated hospital course accompanied by postoperative suprasellar tumor apoplexy, meningitis, and frontal lobe brain infarction. After being referred to our home institution, a year later, we recommended surgery. We were able to successfully resect the remaining residual tumor via endoscopic endonasal transtuberculum approach without complication.

Case 3: A 21-year-old male underwent complete resection of the GPA using our proposed surgical technique of a primary transtuberculum transplanum approach, followed by a secondary transsellar approach. The patient experienced no postoperative complications.

The proposed study introduces a new surgical approach for GPAs that led to the complete resection of a GPA without complication. We recommend that surgeons utilize this “Second Floor” technique when managing giant pituitary adenomas.