Clinical Significance of Primary Tumor Resection in Perihilar Cholangiocarcinoma with Positive Peritoneal Lavage Cytology.

BACKGROUND

The prognostic impact of positive peritoneal lavage cytology (CY+) in patients with perihilar cholangiocarcinoma (PHC) remains unclear. The present study investigated the clinical significance of primary tumor resection of CY+ PHC.

METHODS

We retrospectively evaluated 282 patients who underwent surgery for PHC between September 2002 and March 2022. The patients' clinicopathological characteristics and survival outcomes were compared between the CY negative (CY-) resected (n = 262), CY+ resected (n = 12), and CY+ unresected (n = 8) groups. Univariate and multivariate analyses were performed to identify prognostic factors for overall survival.

RESULTS

The expected residual liver volume was significantly higher in the CY+ resected group (61%) than in the CY- resected (47%) and CY+ unresected (37%) groups (p = 0.004 and 0.007, respectively). The CY+ resected group had a higher administration rate of postoperative therapy than the CY- resected group (58% vs. 16%, p = 0.002). Overall survival of the CY+ resected group was similar to that of the CY- resected group (median survival time [MST] 44.5 vs. 44.6, p = 0.404) and was significantly better than that of the CY+ unresected group (MST 44.5 vs. 17.1, p = 0.006). CY positivity was not a prognostic factor according to a multivariate analysis in patients with primary tumor resection.

CONCLUSIONS

The CY+ resected group showed better survival than the CY+ unresected group and a similar survival to that of the CY- resected group. Resection of the primary tumor with CY+ PHC may improve the prognosis in selected patients.