Discuss the rationality of the new substage IB of FIGO 2018 cervical cancer staging system

Abstract Objective: To explore the rationality of the new stage IB of International Federation of Gynecology and Obstetrics (FIGO) 2018 cervical cancer from the open surgical oncology perspective. Methods: Patients with FIGO 2018 stage IB cervical cancer were screened from the clinical diagnosis and treatment for cervical cancer in China (Four C) database including cases from 47 hospitals in mainland China between 2004 and 2018.Firstly, we classified the lymph node-positive cases in the FIGO 2009 stage IB as stage “IIIC-IB”.Then,using Real World Study(RWS) method,we retrospectively compared the 5-year overall survival (OS) and disease-free survival (DFS)of patients with FIGO2018 staged IB1、IB2、IB3 and IIIC-IB . Results:The results were as follows: 1210 cases were in stage IB1, 1315 cases were in stage IB2, 470 cases were in stage IB3, and 868 cases were in stage “IIIC-IB”.(1) In the whole study population, Kaplan-Meier analysis showed statistically meaningful differences in 5-year OS and 5-year DFS in patients with stage IB1、IB2、IB3 and IIIC-IB cervical cancer (OS: 98.4% vs 94.8% vs 92.1%vs 81.9% , P<0.001; DFS: 94.0% vs 90.7%vs 90.3% vs74.9%, P<0.001).(2)Cox multivariate analysis showed:for stage IB1、IB2，IB1 was an independent protective factor for 5-year OS (HR=0.438, 95% CI: 0.245-0.785,P=0.006),but IB1 was not an independent protective factor for 5-year DFS (P=0.073).For stage IB2、IB3,stage IB3 was not an independent risk factor for 5-year OS and 5-year DFS (OS：P=0.120; DFS：P=0.828).(3) For stage IB1、IB2、IB3、IIIC-IB, Kaplan-Meier analysis and cox multivariate analysis both showed a higher risk of death and death/recurrence in the stageIIIC-IB than the stage IB. Conclusion: The new FIGO 2018 staging strategy is helpful for further distinguishing the survival outcomes of patients with different IB substages, especially IB1、IB2 , but it is not significant for those with IB2、IB3 substages. Patients in the FIGO2009 stage IB disease with positive lymph node metastasis are classified in the FIGO 2018 stage IIIC-IB group, which is helpful for further guiding clinical decision-making and prognosis evaluation.