Impact of chemotherapy cycles on oncological outcomes in elders with locally advanced cervical cancer treated with concurrent chemoradiotherapy

Introduction To investigate the association between chemotherapy (CMT) cycles and oncological outcomes in elders with locally advanced cervical cancer (LACC) who treated with concurrent chemoradiotherapy (CCRT). Methods We retrospective studied 498 elders with LACC who treated with radiotherapy (RT) or CCRT between 2002 and 2018. Patients were divided into three groups: RT, CCRT with 1-4 and CCRT with 5-6 cycles of CMT. We compared progression-free survival (PFS) and overall survival (OS) among the three groups and explored survival prognostic factors via multivariate analysis and time-varying analysis effect. Results There were 453 eligible patients; 222, 119 and 112 patients who received RT, CCRT with 1-4 and CCRT with 5-6 cycles of CMT, respectively. Patients in the RT group had older age, poorer performance status, more treatment with conventional RT technique and earlier treatment year comparing with both CCRT groups. Patients who received 5-6 cycles of CMT were less to have underweight, comorbidities and anaemia compared with the RT group. There were patients with lower FIGO stage in 5-6 cycles than in 1-4 cycles of CMT and RT groups. The 5-year PFS and OS between RT, CCRT with 1-4 and CCRT with 5-6 cycles of the CMT group were significantly different. Performance status, comorbidity, histology, FIGO stage and total received 5-6 CMT cycles were significant prognostic factors of PFS and OS. However, the benefits of receiving 5-6 CMT cycles were evidenced only within the first 2.5 years. Conclusion Elders with LACC who received 5-6 cycles of CMT concurrently with RT can improve PFS and OS, but the benefit persisted only within the first 2.5 years.