Long-Term, Prospective Performance of the MD Anderson Dysphagia Inventory in “Low-Intermediate Risk” Oropharyngeal Carcinoma After Intensity Modulated Radiation Therapy

Purpose To characterize long-term MD Anderson Dysphagia Inventory (MDADI) results after primary intensity modulated radiation therapy (IMRT) for oropharyngeal carcinoma (OPC) among patients with “low-intermediate risk” OPC who would be eligible for current trials (eg, ECOG 3311, NRG HN002, CRUK PATHOS). Methods and Materials A retrospective pooled analysis combined data from 3 single-institution clinical trials for advanced-stage head and neck carcinoma. Inclusion criteria were clinical stage III/IV OPC (T1-2/N1-2b, T3/N0-2b) treated with definitive split-field IMRT and prospectively collected MDADI at baseline and at least 1 posttreatment interval available in trial databases. Patients were sampled to represent likely human papillomavirus (HPV)-associated disease (HPV⁺/p16⁺ or <10 pack-years if HPV/p16 unknown). The MDADI composite scores were collected at baseline and 6, 12, and 24 months after treatment. Pairwise tests were Bonferroni corrected for multiple comparisons. Results Forty-six patients were included. All received bilateral neck irradiation with a median dose of 70 Gy and systemic therapy (57% concurrent, 43% induction only). Overall the mean baseline MDADI composite score was 90.1, dropping to 74.6 at 6 months (P<.0001) and rising to 78.5 (P<.0001) and 83.1 (P=.002) by 12 and 24 months relative to baseline, respectively, representing a clinically meaningful drop in MDADI scores at 6 months that partially recovers by 24 months (6 vs 24 months, P=.05). Poor MDADI scores (composite <60) were reported in 4%, 11%, 15%, and 9% of patients at baseline and 6, 12, and 24 months, respectively. Fifteen percent of patients had a persistently depressed composite score by at least 20 points at the 24-month interval. Conclusion “Low-intermediate risk” patients with OPC treated with laryngeal/esophageal inlet dose-optimized split-field IMRT are highly likely to report recovery of acceptable swallowing function in long-term follow-up. Only 15% report poor swallowing function and/or persistently depressed MDADI at 12 months or more after IMRT. These data serve as a benchmark future trial design and endpoint interpretation.