Oropharyngeal cancer spreads later in patients with HPV

Last Updated: 2015-03-09

By Will Boggs MD

NEW YORK (Reuters Health) - Distant metastases of oropharyngeal squamous cell carcinoma (OPSCC) occur later in patients with human papillomavirus (HPV)-positive tumors, researchers report.

"The late onset of distant metastases in HPV-positive patients confirms our observations over the last several years," Dr. Samuel J. Trosman, from Cleveland Clinic Foundation in Ohio, told Reuters Health by email. "This is unusual as the majority of aerodigestive tract malignancies recur within two years of definitive treatment."

Patients with distant metastases from HPV-positive OPSCC appear to have a better prognosis than do patients with HPV-negative disease, but distant failure may still be the cause of death in these patients.

Dr. Trosman's team investigated the rate, pattern, and timing of distant metastatic failure in 291 patients with advanced-stage OPSCC treated definitively with concomitant chemoradiotherapy, focusing on the differences between the 252 patients with HPV-positive disease and the 39 with HPV-negative disease.

During a median follow-up of 3.1 years, more patients in the HPV-negative group developed distant metastases (23.1% vs 11.1%).

All HPV-negative patients with distant metastases experienced treatment failure within 16 months (median, 7.2 months), whereas HPV-positive patients continued to develop distant metastases as late as six years after the diagnosis (median, 16.4 months; P=0.008).

Patients with HPV-positive disease tended to have more distant metastasis sites than did patients with HPV-negative disease. Nearly a third of patients with HPV-positive disease had dissemination to more than two subsites, compared to only 11% of patients with HPV-negative disease, although this difference was not statistically significant.

Patients with HPV-positive disease also had distant metastases to several atypical sites, including intra-abdominal and axillary lymph nodes, skeletal muscle, brain, kidney, skin, pericardium, and peritoneum.

Estimated three-year overall survival was significantly higher in the HPV-positive group (89.9% vs 62.0%, p<0.001), and patients with HPV-positive disease had a longer median overall survival after distant spread (25.6 vs 11.1 months, p<0.001), according to the March 5 JAMA Otolaryngology - Head and Neck Surgery online report.

"In treating and monitoring patients with HPV-positive squamous cell carcinoma of the oropharynx, a clinician may need to see the patient for oncologic surveillance at shorter intervals than is common practice once the patient is over one year with no evidence of disease," Dr. Trosman said. "The clinician must also beware of atypical sites of metastatic disease presenting as localized pain, mental status changes, etc., as some of our patients have."

Dr. Chamindle Punyadeera from Queensland University of Technology, Brisbane, Australia, who recently summarized trends in the etiology and treatment of HPV-positive head and neck cancers, told Reuters Health by email, "Treatment strategies need to change between HPV positive/negative patients, and follow-up should reflect that as the biology of the disease and subsites for metastasis and frequency varies."

"The difference between locoregional metastases, extensions of locoregional spread, and distant metastases needs to be investigated," Dr. Punyadeera said. "Circulating tumor cells may be able to give an earlier snapshot of the disseminated tumor spread through the lymphovasculature. Current radiography for distant metastases requires CT/MRI scans to show macrometastatic foci; however, micrometastases cannot be detected using conventional imaging."

SOURCE: http://bit.ly/1EMjZH6

JAMA Oncol 2015.