Which factors predict parametrial involvement in stage IB cervical cancer? A Chinese multicentre study.

OBJECTIVE:To explore the clinicopathological risk factors influencing parametrial involvement (PI) in stage IB cervical cancer patients and compare the oncological outcomes between Q-M type B radical hysterectomy (RH) group and Q-M type C RH group. METHODS:Univariate and multivariate analyses were performed to explore the clinicopathological factors related to PI. Overall survival (OS) and disease-free survival (DFS) in patients with stage IB cervical cancer who underwent Q-M type B or Q-M type C RH under different circumstances of PI were also compared before and after propensity score matching (1:1 matching). RESULTS:A total of 6358 patients were enrolled in this study. Depth of stromal invasion>1/2 (HR: 3.139, 95% CI: 1.550-6.360; P = 0.001), vaginal margin (+) (HR: 4.271, 95% CI: 1.368-13.156; P = 0.011), lymphovascular space invasion (LVSI) (+) (HR: 2.238, 95% CI: 1.353-3.701; P = 0.002) and lymph node metastases (HR: 5.173, 95% CI: 3.091-8.658; P < 0.001) were associated with PI. Among the 6273 patients with negative PI, those in the Q-M type B RH group had a higher 5-year OS and DFS than those in the Q-M type C RH group before and after 1:1 matching. Among the 85 patients with positive PI, Q-M type C RH showed no survival benefits before and after 1:1 matching. CONCLUSION:Stage IB cervical cancer patients with no lymph node metastasis, LVSI(-) and depth of stromal invasion ≤1/2 may be considered for Q-M type B radical hysterectomy.