The Prognostic Significance of Pretreatment Leukocytosis in Patients With Anal Cancer Treated With Radical Chemoradiotherapy or Radiotherapy

Abstract

BACKGROUND: 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. OBJECTIVE: 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. DESIGN: This is a retrospective cohort study. SETTING AND PATIENTS: 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. MAIN OUTCOME MEASURES: The primary outcomes were disease-free and overall survival. RESULTS: 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). LIMITATIONS: 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. CONCLUSIONS: 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.