Survival in patients with human papillomavirus positive tonsillar cancer in relation to treatment.

The incidence of tonsillar cancer and the proportion of human papillomavirus (HPV) positive tonsillar cancer cases have increased in the last decades. In parallel, treatment for tonsillar cancer has been intensified e.g., by accelerated radiotherapy, and chemotherapy, resulting in more side effects. Patients with HPV-positive tonsillar cancer have better prognosis than those with HPV-negative tumors, and the former group could hypothetically benefit from reduced, less-toxic treatment without compromising survival. Here, we therefore evaluated possible differences in overall and disease-specific survival after different oncological treatments in 153 patients with HPV DNA- and P16-positive tonsillar cancer who were diagnosed and treated with intent to cure between 2000 and 2007, in Stockholm, Sweden. Of these patients, 86 were treated with conventional radiotherapy, 40 were treated with accelerated radiotherapy and 27 were treated with chemoradiotherapy. There were no significant differences in overall or disease-free survival between the groups. However, there was a trend, implying a beneficial effect of the intensified treatment, with chemoradiotherapy being better than radiotherapy despite that more patients had stage IV disease in the former group; and accelerated radiotherapy being better than conventional radiotherapy. This needs to be followed further in larger more homogenous groups of patients. In conclusion, patients with HPV-positive tonsillar cancer treated with conventional- or accelerated radiotherapy or chemoradiotherapy disclosed similar survival rates. The trend for better survival and less metastasis after intensified treatment underlines the need for large prospective studies comparing less intense to more intense treatment (chemoradiotherapy).