The impact of induction and/or concurrent chemoradiotherapy on acute and late patient‐reported symptoms in oropharyngeal cancer: Application of a mixed‐model analysis of a prospective observational cohort registry

BACKGROUND: The goal of this study was to comprehensively investigate the association of chemotherapy with trajectories of acute symptom development and late symptom recovery in patients with oropharyngeal cancer (OPC) by comparing symptom burden between induction chemotherapy followed by concurrent chemoradiotherapy (ICRT), concurrent chemo‐radiotherapy (CRT), or radiotherapy (RT) alone. METHODS: Among a registry of 717 patients with OPC, the 28‐item patient‐reported MD Anderson Symptom Inventory–Head and Neck Module (MDASI‐HN) symptoms were collected prospectively at baseline, weekly during RT, and 1.5, 3 to 6, 12, and 18 to 24 months after RT. The effect of the treatment regimen (ICRT, CRT, and RT alone) was examined with mixed‐model analyses for the acute and late period. In the CRT cohort, the chemotherapy agent relationship with symptoms was investigated. RESULTS: Chemoradiation (ICRT/CRT) compared with RT alone resulted in significantly higher acute symptom scores in the majority of MDASI‐HN symptoms (ie, 21 out of 28). No late symptom differences between treatment with or without chemotherapy were observed that were not attributable to ICRT. Nausea was lower for CRT with carboplatin than for CRT with cisplatin; cetuximab was associated with particularly higher scores for acute and late skin, mucositis, and 6 other symptoms. The addition of ICRT compared with CRT or RT alone was associated with a significant increase in numbness and shortness of breath. CONCLUSION: The addition of chemotherapy to definitive RT for OPC patients was associated with significantly worse acute symptom outcomes compared with RT alone, which seems to attenuate in the late posttreatment period. Moreover, induction chemotherapy was specifically associated with worse numbness and shortness of breath during and after treatment. LAY SUMMARY: Chemotherapy is frequently used in addition to radiotherapy cancer treatment, yet the (added) effect on treatment‐induced over time is not comprehensively investigated. This study shows that chemotherapy adds to the symptom severity reported by patients, especially during treatment.