Significance of Malignant Peritoneal Cytology on the Survival of Women with Early-Stage Cervical Cancer: A Japanese Gynecologic Oncology Group Study

This study examined the association between peritoneal cytology and survival in early-stage cervical cancer. This is a nationwide multicenter retrospective study, examining consecutive women with clinical stage IB1-IIB cervical cancer who underwent radical hysterectomy with available peritoneal cytology results from 2004–2008. Propensity score inverse probability of treatment weighting was used to assess the impact of malignant peritoneal cytology on survival. Among 1409 analyzed cases, 88 (6.2%) had malignant peritoneal cytology. On weighted models, malignant peritoneal cytology was associated with decreased disease-free survival (hazard ratio (HR) 1.78, 95% confidence interval (CI) 1.36–2.32) and overall survival (OS, HR 1.93, 95% CI 1.44–2.59). On sensitivity analyses, malignant peritoneal cytology was associated with decreased OS in adenocarcinoma/adenosquamous carcinoma, high-risk early-stage disease and those who received concurrent chemo-radiotherapy. However, among women who received postoperative systemic chemotherapy, malignant peritoneal cytology was not associated with OS (HR 1.21, 95% CI 0.72–2.04). A systematic review, including our results, showed that malignant peritoneal cytology was associated with decreased OS (HR 4.03, 95% CI 1.81–8.99) and increased recurrence in squamous carcinoma (odds ratio 1.89, 95% CI 1.05–3.39) and adenocarcinoma (odds ratio 4.30, 95% CI 2.30–8.02). In conclusion, the presence of malignant cells in peritoneal cytology is associated with decreased survival in early-stage cervical cancer. The possible benefit of systemic chemotherapy in this subgroup merits further investigation.