Acute‐phase response reactants as objective biomarkers of radiation‐induced mucositis in head and neck cancer

BACKGROUND: Current evaluation of radiation-induced mucositis in head and neck cancer relies on subjective scoring with interrater variability. We evaluated serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as objective markers of radiation-induced mucositis. METHODS: Weekly serum CRP and ESR levels were measured in patients treated for head and neck cancer with radiation ± chemotherapy. Acute radiation toxicity was evaluated using National Cancer Institute of Canada-Common Toxicity Criteria (NCIC-CTC) version 2.0 and the Head and Neck Radiotherapy Questionnaire (HNRQ). RESULTS: ESR and CRP levels were significantly elevated by 3 weeks (p = .01) and 6 weeks (p = .0002), respectively, and independent of age or pretreatment surgery. ESR was significantly dependent on radiation dose (p = .0004) and significantly higher with chemoradiation (p = .03). CONCLUSION: Serum ESR and CRP rise reliably in a radiation dose-dependent manner. ESR correlated with clinical symptoms and distinguished patients receiving chemoradiation. ESR and CRP may be an objective and sensitive marker of radiation-induced mucositis.