Prognosis of HPV-Positive and -Negative Oropharyngeal Cancers Depends on the Treatment Modality

Abstract

The association between human papilloma virus (HPV) and oropharyngeal carcinoma is a topical issue due mainly to the rapid increase in incidence over recent years. These tumors are etiopathogenetically, epidemiologically, and clinically different from other carcinomas at this location. They have a better prognosis in that they are more chemo-and radiosensitive. Indeed, this has been shown by many extensive retrospective and prospective studies. HPV status is considered an integral part of a standard histopathological examination and is included as a new biological parameter in TNM classification. The results of 77 patients who were treated non-surgically for locally advanced oropharyngeal carcinoma at a single university ear, nose, and throat clinic were analyzed retrospectively. Overall and specific survival of those with HPV-positive (HPV+) tumors was better that those for HPV negative (HPV-) tumors. With the exception of TNM classification, HPV positivity appeared to be the strongest predictor of local control, and of overall and specific survival, regardless of the type of treatment. However, smoking and p53 positivity were significant negative predictors of overall survival. Patients with HPV-associated tumors had a significantly better prognosis, regardless of treatment type. The difference between treatment modalities was confirmed for the whole group of patients, but not for the HPV+ and HPV-patients specifically, most probably due to the small number of patients enrolled. The results obtained herein may constitute the first step toward the concept of treatment de-escalation in those with HPV-associated oropharyngeal carcinoma; however, this decision can be based only on the results of current extensive randomized trials. Specification of the optimal de-escalation scheme, or the choice of treatment modality, for which the difference in treatment results is most pronounced, has yet to be identified. This work was supported by grants of the Ministry of Health of the Czech Republic IGA NT12483-4/2011 and AZV 15-31627A. he authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 21. 9. 2018 Accepted: 14. 5. 2019.