Minimum absolute lymphocyte count during radiotherapy as a new prognostic factor for nasopharyngeal cancer

BACKGROUND: The purpose of this study was to investigate whether the minimum absolute lymphocyte count (ALC) during radiotherapy (RT) could predict clinical outcome in patients with nasopharyngeal cancer (NPC). METHODS: We analyzed 70 patients with NPC including 63 patients treated with chemoradiotherapy and used multivariate analysis to determine whether minimum ALC affected clinical outcome. RESULTS: Patients were grouped by minimum ALC, with a cutoff of 245 cells/μL. Five-year disease-specific survival (DSS) and progression-free survival (PFS) for patients with minimum ALC ≥245 versus minimum ALC <245 were 88.1% versus 60.8% (p = .004) and 71.2% versus 35.2% (p = .004). All 10 patients with minimum ALC <120 experienced disease progression. Four of 6 patients (67%) with ALC <120 who died experienced disease progression within 6 months. CONCLUSION: Minimum ALC may predict poor 5-year DSS and should be evaluated by prospective studies.