Absolute Lymphocyte Count in Cervical Cancer Patients Prior to Definitive Chemoradiotherapy: a Prognostic Indicator?

Abstract

Objective: Baseline lymphopenia is associated with poor prognosis in various malignancies. This study aimed to examine the prognostic value of pretreatment lymphocyte count in cervical cancer patients in Hong Kong. Methods: A cohort of 198 cases of cervical cancer patients without evidence of metastatic disease (i.e., International Federation of Gynecology and Obstetrics stage IB to IVA), who completed definitive chemoradiotherapy from January 2009 to December 2014 was analysed. Baseline clinical and pretreatment blood test data were collected. Definitive treatment had included external radiotherapy and brachytherapy with concurrent weekly cisplatin 40 mg/m 2 . Log-rank tests and multivariable Cox regression were used to evaluate the association between haematological parameters and survival. Study endpoints were overall survival (OS), recurrence-free survival (RFS), and late radiation-induced grade 3-4 toxicity. Results: Median follow-up period was 6.52 years. A pretreatment absolute lymphocyte count ≤1.7 × 10 9 /L was associated with a significantly worse 5-year OS (68.7% vs. 84.4%, p = 0.005). Multivariate analysis confirmed pretreatment lymphocyte count to be an independent predictor of RFS (adjusted hazard ratio = 0.58; 95% confidence interval [CI] = 0.34-0.99, p = 0.046) and OS (adjusted hazard ratio = 0.47; 95% CI = 0.25-0.88, p = 0.018). Absolute lymphocyte count was not associated with late grade 3-4 radiation toxicity. Conclusion: Our data in a local cohort add evidence to findings in other studies that pretreatment absolute lymphocyte count is an independent predictor of both OS and RFS in cervical cancer patients receiving definitive chemoradiotherapy