HPV impact on oropharyngeal cancer radiological staging: 7th vs 8th edition of AJCC TNM classification

Purpose: To evaluate the agreement between pathological and radiological staging in oropharyngeal cancer by comparing the 7th and the 8th edition of the AJCC TNM system. Methods: This retrospective cohort study included 57 cases of oropharyngeal cancer with lymph node metastases staged with the 7th and 8th editions of the AJCC TNM system. Comparison between clinical and radiological features and differences in agreement rates were calculated between radiological and pathological staging for the primary tumor (T) and lymph nodes (N) in HPVpos and HPVneg cases. Results: Comparison of HPVpos and HPVneg revealed a significantly different distribution between early and advanced stages in the 8 th edition, with a relevant number of HPVpos patients redefined from advanced stages whit the 7 th ed. to early stages with 8 th ed. (p < 0.01); no significant differences were found when comparing all diagnostic methods for T and N. Conclusions: The 8th edition of the AJCC TNM seems to lead to better pretreatment staging. For both HPVpos and HPVneg, the agreement between pretreatment radiological and pathological staging.