Retrospective analysis of the incidence and predictive factors of parametrial involvement in FIGO IB1 cervical cancer

Background and objectives: Radical surgery is the standard primary treatment for patients with stage IB1 (FIGO 2009 staging) cervical cancer due to latent parametrial involvement. Recent studies suggested that less radical surgery was applicable for patients with no or low risk of parametrial involvement. In this study, we aimed to determine the incidence and possible predictive factors of parametrial involvement in patients with stage IB1 cervical cancer so as to evaluate whether less radical surgery was suitable for selected patients.

Methods: Clinical data of patients who underwent type C radical hysterectomy with pelvic lymphadenectomy and diagnosed as stage IB1 cervical cancer at Union Hospital, Wuhan, China from October 2014 to December 2017 were collected and analysed retrospectively. The incidence of parametrial involvement was calculated and the risk factors for parametrial involvement were evaluated by univariate and multivariate logistic regression.

Results: Among 282 eligible patients, 33 (11.7%) had parametrial involvement. Postmenopause, lymphovascular space invasion (LVSI), lymph node metastasis (LNM), deep stromal invasion (outer 1/3) and tumor size larger than 2 cm were statistically associated with parametrial involvement. Multivariate analysis showed that LNM (OR = 11.431; 95%CI: 3.455 - 37.821), deep stromal invasion (OR = 6.080; 95%CI: 1.814 - 20.382) and LVSI (OR = 7.147; 95%CI: 1.863-27.411) remained as independent risk factors for parametrial involvement in patients with stage IB1 cervical cancer.

Conclusions: The incidence of parametrial involvement in stage IB1 cervical cancer is non-negligible. Only LNM, LVSI and deep stromal invasion were independent predictors, which were not easy to evaluate accurately before surgery. Less radical surgery requires modified pre-treatment evaluation methods and prospective data support.