Endoscopic Endonasal Surgery as an Alternative to Radiotherapy for Recurrent or Residual Pituitary Adenomas

Background: Recurrent or residual tumors are often treated with nonsurgical therapies such as observation, medical therapy, radiotherapy, or radiosurgery, all of which have low procedure-related morbidity. However, there are limited reports on the role of endoscopic endonasal surgery for recurrent or residual pituitary adenomas. In this study, we analyze a series of endoscopically resected recurrent and residual pituitary adenomas that had been previously operated on with a transsphenoidal microscopic or endoscopic approach. Clinical outcomes and complications are reported.

Objective: The aim of this study is to demonstrate that endoscopic endonasal surgery is a valid and safe alternative to radiotherapy in patients with recurrent or residual pituitary adenomas.

Methods: Retrospective analysis was conducted on a series of consecutive patients at a single tertiary referral institution who underwent endoscopic endonasal surgeries for residual or recurrent pituitary adenomas after original transsphenoidal microscopic or endoscopic surgeries. Thirty-three patients met the inclusion criteria. Patient complications, resection, and remission rates were assessed.

Results: Out of 33 patients, 19 had nonfunctional adenomas and 14 had functional adenomas, including five growth hormone-secreting tumors and nine adrenocorticotropic hormone-secreting tumors. Of the five growth hormone-secreting adenomas, all were macroadenomas; three also had a cavernous sinus invasion (Knosp Grade 3 or 4). A cure (IGF-1 < 100) was obtained in 100% of the tumors that invaded the cavernous sinus. The overall cure rate was 60%. Of the nine adrenocorticotropic hormone-producing adenomas, six were microadenomas, and three were macroadenomas; one also had a cavernous sinus invasion (Knosp Grade 3 or 4). A cure (salivary and free urine cortisol) was obtained in 50% of the microadenomas and 50% of the macroadenomas. The overall cure rate was 66.7%. Out of 19 cases with nonfunctional adenomas, all had macroadenomas and 11 presented visual impairment. Radiographically, 10 of the cases were Knosp Grades 3 and 4. Gross total resection was achieved in six (31.5%) cases. Total or partial improvement of vision was obtained in 90% of the patients. The mean follow-up was 20 months for patients with functional adenomas and 15 months for those with nonfunctional adenomas. No postoperative CSF leaks, postsurgical visual disorders, or cranial nerve palsies were detected.

Conclusion: Endoscopic endonasal surgery can achieve similar cure rates in reoperations as radiotherapy without exposing patients to the long-term side effects of this therapy.