2026 Proffered Presentations
S259: REMISSION RATES IN REPEAT ENDOSCOPIC TRANSSPHENOIDAL SURGERY FOR RECURRENT GROWTH HORMONE SECRETING PITUITARY ADENOMA
Drew A Thibault, DO1; Christine K Lee, MD, PhD2; Juan Carlos Fernandez-Miranda, MD, FACS3; Karam Asmaro, MD1; 1Corewell William Beaumont University Hospital; 2The Warren Alpert Medical School of Brown University; 3Stanford Brain Tumor, Skull Base, and Pituitary Centers
Growth Hormone secreting pituitary adenomas account for 8-16% of pituitary adenomas with an incidence rate of approximately 11 cases per million person years in the US. GH-secreting tumors typically occur in the 5th decade of life and cause acromegaly, typically presenting with enlarged hands and feet, coarsened facial features, hyperhidrosis, and arthralgias. The standard of care has long been transsphenoidal surgery (TSS), first with a surgical microscope, and now almost exclusively with the use of endoscopes. With modern advances, remission rates following initial TSS exceed 80% and have steadily increased over the past decades as surgical technology has improved accessibility to skull base corridors. While first line therapy is quite effective, the role of re-operation in recurrent acromegaly is less defined. Successful repeat TSS has been documented, however the remission rate of re-operation varies greatly in the literature. Modern advancements in the field of endoscopic skull base surgery necessitate additional and updated investigations into the efficacy of re-operation for GH-secreting pituitary adenomas. The most recent systematic review included studies from 1988 – 2020 and reported a remission rate of 37.4% for 608 patients who underwent repeat TSS for GH-secreting pituitary adenomas. A 2017 study of 161 repeat TSS patients reported a remission rate of 46.8%. SRS, a common alternative to re-operation, has reported remission rates of 57-59% at 10 years yet is associated with more hormonal complications. Data collected from a single surgeon’s experience at two institutions between the years of 2019 and 2023 indicate that the true modern remission rate following repeated TSS for acromegaly may be much higher. The present dataset includes thirty-one patients of which fourteen were male and seventeen were female with an average age of 42.4 years (range 27-67). Of the twenty-eight patients for whom long-term follow-up information is available, biochemical remission (criteria IGF-1 WNL at 3 months) was achieved in twenty-two patients for a remission rate of 78.6%. Gross total resection (GTR) was achieved in twenty patients with the histopathology of five patients pending at time of writing. In all cases with pending pathological reports, the resection was considered gross total intraoperatively. Patient complications were minimal: three patients developed transient cranial nerve palsies that resolved within four months, two patients developed mild diplopia, and one patient developed jerking myotonic movements one week after surgery. Patient follow-up was on average 214 days with a median of 119 days. Overall, the current dataset demonstrates that patients with recurrent or un-remitting acromegaly can be safely and effectively treated with repeat TSS. As evidenced in Figure 1, the remission rate of the current dataset is higher than most previous publications, and the highest among those investigating more than twenty patients. This increased remission rate is likely secondary to the rapid advancements in modern endoscopy, which allow surgeons to safely access aspects of the cavernous sinus and other skull base corridors in which tumors were previously unable to be safely removed. Broader multi-institutional investigations are necessary to confirm the generalizability of these results.
