Serum lactate dehydrogenase is a predictive biomarker in patients with oropharyngeal cancer undergoing radiotherapy: Retrospective study on predictive factors.

BACKGROUND: The present study aimed to evaluate the prognostic factors in human papillomavirus (HPV)-positive and HPV-negative oropharyngeal cancer (OPC) treated with definitive radiotherapy. METHODS: We retrospectively evaluated 101 patients with OPC who underwent definitive radiotherapy between 2008 and 2018. RESULTS: The median follow-up period of the surviving patients was 68 months (range, 8-164 months). The 5-year overall survival rate was 69.8%. Univariate analyses revealed that poor survival was associated with male sex, smoking >/=30 pack-years, Eastern Cooperative Oncology Group performance status >/=1, tumor-node-metastasis (TNM) stage III-IV (8th edition), HPV-negativity, serum lactate dehydrogenase (LDH) >/=202, C-reactive protein/albumin ratio >/=0.15, and lymphocyte-to-monocyte ratio <2.90. In multivariate analyses, poor survival was independently correlated with smoking >/=30 pack-years (p < 0.01) and LDH >/=202 (p = 0.02). CONCLUSIONS: The present study suggested that high LDH levels predicted poor survival after definitive radiotherapy for patients with both HPV-positive and HPV-negative OPC.