Radiographic and clinical outcomes using intraoperative magnetic resonance imaging for transsphenoidal resection of pituitary adenomas

OBJECTIVE

The utility and safety of intraoperative MRI (iMRI) for resection of pituitary adenomas is not clearly established in the context of advances in endoscopic approaches. The goal in this study was to evaluate the safety and efficacy of iMRI for pituitary adenoma resection, with endoscopic transsphenoidal (ETS) versus microscopic transsphenoidal (MTS) approaches.

METHODS

Radiographic and clinical outcomes of all pituitary adenomas resected using iMRI between 2008 and 2017 at a single institution were retrospectively evaluated.

RESULTS

Of 212 tumors treated, 131 (62%) underwent further resection based on iMRI findings, resulting in a significant increase in gross-total resection on postoperative MRI compared with iMRI (p = 0.0001) in both ETS and MTS groups. iMRI increased rates of gross-total resection for cavernous sinus invasion Knosp grades 1 and 2, but not in Knosp ≥ 3 across treatment groups (p < 0.0001). The extent of resection on postoperative MRI was significantly correlated with increased progression-free survival (p < 0.0001). Initial hormone remission off medical therapy was achieved in 64%, with a significantly higher rate of remission in tumors resected via the ETS approach (81%) compared with the MTS approach (55%) (p = 0.02). The rate of persistent new hormone deficit was low at 8%, including a 2.8% rate of permanent diabetes insipidus, and 45% of patients had improvement in preoperative hormone deficit following surgery. Serious postoperative complications including CSF leaks requiring reoperation were rare at 1%, with no postoperative infections.

CONCLUSIONS

These results suggest that iMRI is a safe and effective method of increasing the extent of resection for pituitary adenomas while preserving hormone function. When paired with the endoscope, iMRI may offer the ability to tailor more aggressive removal of tumors while optimizing pituitary function, resulting in high rates of secretory hormone remission. Secretory tumors and adenomas with Knosp grade < 3 cavernous sinus invasion may benefit most from the use of iMRI.

McKittrick-Wheelock syndrome presenting with dermatomyositis and rectal prolapsed

McKittrick–Wheelock syndrome is a rare disease characterized by a large hypersecretory rectosigmoid villous adenoma resulting in persistent large volume diarrhea, electrolyte abnormalities, and renal dysfunction. We report an unusual presentation of this syndrome in a patient who developed persistent diarrhea along with dermatomyositis and rectal prolapse and was later discovered to have a large rectal villous adenoma along with a smaller sigmoid tubulovillous adenoma. In our literature review, we were able to find one case report of a dermatomyositis occurring in conjunction with a tubulovillous adenoma and few case reports of rectal prolapse in the setting of a secretory villous adenoma. However, there were no reports on both occurring in association with McKittrick–Wheelock syndrome. This report highlights the variable manifestations of colorectal adenomas and the importance of searching for an underlying neoplastic entity in patients with new onset dermatomyositis or rectal prolapse or both.