241MO - Survival impact of pretreatment absolute lymphocyte count in cervical cancer patients receiving definitive chemoradiation

Background

Lymphopenia has been suggested to reflect low host immune reactivity. Studies have shown that baseline lymphopenia is associated with poor prognosis in various malignancies. The impact of pretreatment lymphocyte count on survival in cervical cancer patients is investigated in this study.

Methods

A cohort of non-metastatic cervical cancer patients who completed definitive chemoradiation from January 2009 to December 2014, in a tertiary oncology centre, was included. Patients were restaged according to the 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. Patients with active infection and autoimmune conditions were excluded. Definitive treatment included a combination of external radiotherapy and brachytherapy with concurrent weekly cisplatin 40mg/m². Baseline clinical information and pretreatment blood tests were collected. Log rank tests and multivariable Cox regression were used to evaluate the association between haematological parameters and survival. Study endpoints were overall survival (OS), progression free survival (PFS), late radiation-induced grade 3-4 toxicity.

Results

Median follow-up was 6.3 years with a total of 153 eligible cases in our study. Multivariate analysis confirmed pretreatment lymphocyte count to be an independent predictor of OS (adjusted hazard ratio 0.47; 95% confidence interval 0.30 – 0.97, p = 0.040) and PFS (adjusted hazard ratio 0.56; 95% confidence interval 0.32 – 0.98, p = 0.045), adjusted for age, performance status, FIGO stage, histology, Charlson comorbidity score and cumulative cisplatin dose. Lower pretreatment absolute lymphocyte count (<1.7x10⁹/L) was associated with significantly worse 5-year OS (76.1% vs 86.2%, p=0.033). Lymphocyte count was not associated with late radiation-induced grade 3-4 toxicity.

Conclusions

Pretreatment lymphocyte count is an independent predictor of both OS and PFS in cervical cancer patients receiving definitive chemoradiation. It should be considered as an integral component for building prognostic models for cervical cancer patients in future.

Clinical trial identification

Editorial acknowledgement