Mesenteric Lymph Node Involvement as a Prognostic Factor in Ovarian Cancer: A Study Using a Standardized Detection Method.

BACKGROUND

Mesenteric lymph node (MLN) involvement is frequently observed in patients undergoing cytoreductive surgery for ovarian cancer (OC) with rectosigmoid invasion. However, MLN detection methods are not standardized, and the clinical significance of MLN involvement remains controversial. This study aimed to investigate the clinical significance of MLN involvement in patients with OC using a standardized detection method.

METHODS

The study included 171 patients with stage II, III, or IV OC who underwent cytoreductive surgery. The analysis detected MLN in patients who underwent rectosigmoid resection in the same manner as for colorectal cancer: systematic regional lymph node dissection followed by systematic extraction and histopathologic examination of MLN.

RESULTS

Of the 171 patients, 57 underwent rectosigmoid resection. In 56 patients (98.2 %), MLNs were detected, with a median of nine (range, 0-51) dissected nodes. Histopathologic examination confirmed MLN involvement in 30 of these 57 patients. The independent prognostic factors for progression-free survival identified by multivariate analysis were residual tumor status (P = 0.002), ascitic cytology (P = 0.034), and MLN involvement (P = 0.010). Among the 86 patients who underwent complete cytoreductive surgery, MLN involvement was significantly associated with worse prognosis (P < 0.001). However, for the 85 patients who underwent optimal or suboptimal cytoreductive surgery, MLN involvement was not a significant prognostic factor.

CONCLUSIONS

In patients with OC, MLN involvement is an important prognostic factor, particularly for those undergoing complete cytoreductive surgery. Evaluation of MLNs using a standardized detection method in the same manner as for colorectal cancer may help identify patients at higher risk for a poor prognosis.