Lymphopenia and its association with survival in patients with locally advanced cervical cancer

Objective: To evaluate the association between lymphopenia and survival in women with cervical cancer treated with primary chemoradiation.

Methods: A single institution, retrospective analysis of patients with stage IB2-IVA cervical cancer who received upfront chemoradiation from 1998 to 2013 was performed. Complete blood counts from pre-treatment to 36 months post-treatment were analyzed. Lymphopenia and known prognostic factors were evaluated for an association with progression-free (PFS) and overall survival (OS).

Results: Seventy-one patients met study criteria for whom 47 (66%) had a documented total lymphocyte count (TLC) two months after initiating chemoradiation. FIGO stage distribution was 6% Stage I, 46% Stage II, 45% Stage III and 3% Stage IV. Pre-treatment TLC was abnormal (<1000 cells/mm3) in 15% of patients. The mean reduction in TLC was 70% two months after initiating chemoradiation. Severe post-treatment lymphopenia (TLC <500 cells/mm3) was observed in 53% of patients; they experienced inferior median OS (21.2 vs. 45.0 months, P=0.03) and similar 25th percentile PFS (6.3 vs. 7.7 months, P=0.06) compared to patients without severe lymphopenia. Multivariate analysis demonstrated pre-treatment TLC ≥1000 cells/mm3 and post-treatment TLC >500 cells/mm3 had a 77% (HR: 0.23; 95% CI 0.05-1.03; P=0.053) and 58% decrease in hazards of death (HR: 0.42; 95%CI 0.12-1.46; P=0.17) respectively.

Conclusion: More than half of cervical cancer patients treated with chemoradiation experienced severe and prolonged lymphopenia. Although statistical significance was not reached, the findings suggest that pre- and post-treatment lymphopenia may be associated with decreased survival. Further research is warranted, given that lymphopenia could be a reversible prognostic factor.