The prognostic significance of pretreatment leukocytosis in patients with anal cancer treated with radical chemoradiotherapy or radiotherapy.

Abstract

There are emerging data showing the prognostic significance of pretreatment leukocytosis in patients with cervical cancer; it is generally associated with adverse outcome. However, the prognostic impact of leukocytosis in patients with anal cancer has not been previously reported. The purpose of this study was to assess the relationship between pretreatment leukocytosis and clinical outcomes in patients with anal cancer treated with radical chemoradiotherapy or radiotherapy. This is a retrospective cohort study. One hundred twenty-six patients with invasive anal canal cancer, treated with radical chemoradiotherapy or radiotherapy between 2000 and 2008 at 2 major tertiary cancer centers, were evaluated. The primary outcomes were disease-free and overall survival. Median follow-up was 24 months. Pretreatment leukocytosis (white blood cell count >10 × 10/L) was identified in 15.9% (20/126) of patients. After adjusting for sex, tumor size, and stage in a multivariate analysis, leukocytosis remained significantly associated with worse disease-free survival (HR, 2.2; 95% CI, 1.1-4.8; p = 0.045) and worse overall survival (HR, 2.9; 95% CI, 1.1-7.9; p = 0.036). Patients with both leukocytosis and anemia (pretreatment hemoglobin <125 g/L) had the worst prognosis: 2-year disease-free survival 42.1% versus 72.9% for patients without these factors (HR, 2.7; 95% CI, 1.1-6.8; p = 0.033); 2-year overall survival 60.9% versus 89.8% (HR, 4.5; 95% CI, 1.5-13.2; p = 0.006). The study was limited by its retrospective nature and lack of patients with multiple hematologic abnormalities (ie, both anemia and leukocytosis). HIV status was unable to be evaluated. Pretreatment leukocytosis in patients with anal cancer is associated with significantly worse disease-free and overall survival, which appears to be exacerbated with the presence of pretreatment anemia.