Postradiotherapy persistent lymphopenia as a poor prognostic factor in patients with cervical cancer receiving radiotherapy: a single-center, retrospective study

Background Radiotherapy (RT) is effective in cervical cancer; radiation-induced lymphopenia correlates with poor survival outcome in several cancer types. We investigated the association of total lymphocyte count (TLC) with survival outcomes in patients with cervical cancer. Methods We retrospectively reviewed 168 patients with cervical cancer initially treated with definitive RT. We obtained clinicopathological data and TLCs before RT and at the end and at 6 months after RT. Patient-, treatment-, and tumor-specific factors were evaluated to determine their predictive values for overall survival. The association of overall and progression-free survivals with lymphopenia at each point was evaluated. Results Median follow-up duration was 44 (interquartile range: 25–67) months. Median TLCs before RT and at the end and at 6 months after RT were 1625/mm 3 , 400/mm 3 , and 800/mm 3 (interquartile range: 1270–1930/mm 3 , 290–550/mm 3 , and 600–1067/mm 3 ), respectively. For overall survival, in addition to FIGO stage, body mass index, histology, treatment, and presence of para-aortic lymph node metastasis, lymphopenia at 6 months after RT was a poor prognostic factor in multivariate analysis ( P = 0.0026; hazard ratio [HR], 3.06; 95% confidence interval [CI]: 1.48–6.33). For progression-free survival, TLCs before and at 6 months after RT were poor prognostic factors in univariate analysis ( P = 0.0318 and 0.0081, respectively); however, the latter was the only independent prognostic factor in multivariate analysis ( P = 0.0021; HR, 2.67; 95% CI: 1.43–4.99). Conclusion Post-RT persistent lymphopenia could be a poor prognostic factor for patients with cervical cancer who receive RT.