Introduction: Gross-total resection is potentially curative for craniopharyngiomas (CPs) and is often the goal of surgery, but endocrinopathy generally results if the stalk is sacrificed. The decision to sacrifice or preserve the stalk is a difficult one and the consequences of each strategy are not well understood.

Methods: A retrospective review of a prospective cohort of patients who underwent initial resection of CP using the endoscopic endonasal approach over a period of 12 years at Weill Cornell Medical College, New York-Presbyterian Hospital was performed. Post-resection integrity of the stalk was retrospectively assessed using operative notes, videos and post-operative MRI. Tumors were classified based on location into Type I (sellar), Type II (sellar-suprasellar) and Type III (purely suprasellar). Pre- and post-operative endocrine function, rate of GTR, radiation, and complications were reviewed.

Results: A total of 54 endoscopic endonasal procedures for first time resection of CP were identified. The stalk was preserved in 33 (61%) and sacrificed in 21 (39%). GTR was achieved in 26 (79%) patients with stalk preservation and 21 (100%) patients with stalk sacrifice (p=0.035). Stalk preservation surgery achieved GTR and maintained completely normal pituitary function in only 4/33 (12%) patients. Permanent post-operative diabetes insipidus (DI) was present in 16 patients (49%) with stalk preservation and in 20 patients (95%) following stalk sacrifice (p=0.0003). In the stalk preservation group, rates of recurrence and radiation were higher with intentional STR or NTR compared to GTR (71% vs. 10%; p=0.0016 and 100% vs. 23%; p=0.027 respectively).

Conclusions: While the decision to preserve the stalk reduces the rate of postoperative endocrinopathy by roughly 50%, nevertheless significant anterior and posterior pituitary dysfunction often ensues. Stalk preservation also reduces the rate of GTR resulting in an increased rate of recurrence and need for radiation, but if GTR can be achieved, recurrence rates are low.

Patient Care: . If one can preserve the stalk and achieve GTR, this strategy may provide some protection of anterior pituitary endocrine function but a strategy of intentional STR will lead to a high risk of recurrence and radiation without significant increase in endocrine function, and only makes sense in the pediatric population where minimizing hypothalamic damage is a primary goal of surgery.

Learning Objectives: The decision to preserve or sacrifice the stalk must be made on a case by case basis. Our data indicate that while preserving the stalk does hold promise for maintaining some endocrine function, there is still a loss of function in at least 50% and if GTR is attempted, in at least 85%. Moreover, the decision to preserve to stalk reduces rates of GTR and increases the need for radiation and recurrence. These factors should be clearly discussed with patients prior to surgery and factored into the decision as to how best to proceed in the operating room.

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