Supragastric lesser sac: an insidious site for surgical exploration during the debulking surgery in advanced ovarian cancer.

Objective: Metastases in the supragastric lesser sac (SGLS) are not only occult but are also barriers to complete resection of ovarian cancer. We describe a cohort of patients with SGLS disease undergoing debulking surgery.

Methods: We identified all patients who underwent evaluation and eventual resection of SGLS disease as part of cytoreductive surgery for stage IIIC-IVB high-grade epithelial ovarian cancer at our institution from January 2018 to August 2022.

Results: Thirty-three of 286 patients (11.5%) underwent resection of SGLS disease. Metastases in the SGLS were identified by preoperative imaging in 4 of 33 patients (12.1%). The median peritoneal cancer index score was 22 (range, 9-33). Through surgical exploration, metastases were frequently seen in the right diaphragm (100%), hepatorenal recess (97%), lesser omentum (81.8%), left diaphragm (78.8%), supracolic omentum (75.8%), anterior transverse mesocolon (72.7%), splenic hilum (63.6%), ligamentum teres hepatis (60.6%), and gallbladder fossa (51.5%). The lesser omentum was normal in 6 of 33 (18.2%) patients, despite metastases within the SGLS. A total of 54.5% of patients underwent complex surgery (surgical complexity scores; median, 8; range, 3-14). Complete resections were achieved in 19 (57.6%) patients. No complications were related to the resection of SGLS disease. The median length of progression-free survival was 24.8 months (95% confidence interval=16.6-32.9).

Conclusion: Metastases to the SGLS are not uncommon in advanced ovarian cancer, particularly those with widely disseminated disease. Disease in this recess is rarely identified by preoperative imaging and deserves systematic surgical exploration to attain complete cytoreduction.