Morphologic and topographic radiologic features of human papillomavirus-related and -unrelated oropharyngeal carcinoma.

BACKGROUND: The purpose of this study was to compare the clinicoradiologic characteristics of human papillomavirus (HPV)-related (HPV-positive) and HPV-unrelated (HPV-negative) oropharyngeal carcinoma (OPC). METHODS: Primary tumor and lymph node features of HPV-positive and HPV-negative OPCs from 2008 to 2013 were compared on pretreatment CT/MRI. Intrarater/interrater concordance was assessed. Multivariable analyses identified factors associated with HPV-positivity to be used in nomogram construction. RESULTS: Compared to HPV-negative (n = 194), HPV-positive (n = 488) tumors were more exophytic (73% vs 63%; p = .02) with well-defined border (58% vs 47%; p = .033) and smaller axial dimensions; lymph node involvement predominated (89% vs 69%; p < .001) with cystic appearance (45% vs 32%; p = .009) but similar topography. Intrarater/interrater concordance varied (fair to excellent). Nomograms combining clinical (age, sex, smoking pack-years, subsite, T/N classification) and/or radiologic (nonnecrotic tumor and cystic lymph node) features were used to weigh the likelihood of HPV-driven tumors (area under the curve [AUC] = 0.84). CONCLUSION: HPV-positive OPC has different radiologic tumor (exophytic/well-defined border/smaller axial dimension) and lymph node (cystic) features but similar lymph node topography.