According to Dr. Sturgis, patients with HPV-positive oropharyngeal cancers probably do better because they have fewer genetic mutations in their cancers, versus the many mutations found in HPV-negative cancers, the majority of which are related to smoking. “In smoking-related cancers, the tumor cells have many genetic changes that may provide for many options for aggressiveness and resistance to therapy,” he said, whereas radiotherapy and chemotherapy are probably more effective in killing cells with fewer mutations, as in HPV-related cancer.
Explore This IssueNovember 2012
Despite the significant improvement in survival outcomes seen in patients with HPV-positive cancers, HPV status is still not used to determine treatment and is not included in the current staging system for these cancers. “It is a real problem using the current staging system to provide patients [with] accurate estimates of their survival chances, most likely because HPV is not included in the system,” said Dr. Sturgis. “We are hopeful that the future system will incorporate HPV status and the current clinical trials for patients with HPV-related cancers will allow us, in the future, to make better treatment decisions.”
Clinical trials currently underway to evaluate whether using less aggressive treatment for HPV-positive cancers can effectively treat the disease while incurring fewer side effects may change this. “I think we’re right on the verge, in the next five to 10 years, of individualizing treatment based on HPV status,” said Dr. Sturgis.