Immunologic mediators of outcome for irradiated oropharyngeal carcinoma based on human papillomavirus status.

Abstract

PURPOSE\nTo investigate the prognostic value of pre-treatment immune parameters including white blood cell count (WBC) and circulating lymphocyte count (CLC) among patients with oropharyngeal carcinoma treated by radiation therapy.\n\n\nMETHODS AND MATERIALS\nA total of 136 consecutive patients were treated by radiation therapy for locally advanced (stage III/IV) squamous cell carcinoma of the oropharynx with known human papillomavirus (HPV) status. Medical records were reviewed to identify patients with documented pre-treatment laboratory bloodwork. The Kaplan-Meier method and linear regression models were used to evaluate the association between pre-treatment CBC and CLC values with survival endpoints.\n\n\nRESULTS\nOne hundred and eleven patients satisfied inclusion criteria. Median age was 62\u202fyears (range, 22-91). Eighty-four patients were HPV-positive (76%) and 27 (24%) were HPV-negative. There was no difference in WBC and CLC mean values at baseline between HPV-positive and HV-negative (p\u202f>\u202f0.05, for both). Trends were detected in the HPV-positive cohort favoring patients with higher CLC, with respect to 2-year local-regional control (93% vs. 82%, p\u202f=\u202f0.06) and distant control (88% vs. 82%, p\u202f=\u202f0.10) using the median CLC as cut-off. HPV-positive patients with CLC values in the lowest quartile had inferior local-regional control compared to those in the upper 3 quartiles (69% vs. 89%, p\u202f=\u202f0.01).\n\n\nCONCLUSION\nLow pre-treatment CLC was correlated with local-regional recurrence and distant failure among HPV-positive patients. These associations were not observed in the HPV-negative cohort.