CHICAGO—If your partner or spouse has oropharyngeal cancer you are at no extra risk of infection from either the human papillomavirus (HPV) that was likely to have caused the cancer or of oropharyngeal cancer itself. These are the findings from the Human Oral papillomavirus TranSmission in Partners Over Time (HOTSPOT) study data released here at the American Society of Clinical Oncology Annual Meeting (Abstract #CRA6031 ).
Gypsyamber D'Souza PhD, MPH, MS, Associate Professor of Epidemiology at Johns Hopkins Bloomberg School of Public Health, presented the results, which were also discussed at a news conference of highlighted studies.
She explained that patients with this cancer often worry about infecting their long-term partner, especially related to oral sex.
The reassuring evidence from the study, though, was that there was no additional incidence of HPV infection or of cancer in partners as compared with the general population, and that couples in long-term relationships do not need to change their sexual behavior because of a cancer diagnosis.
“Oral HPV transmission is not well understood, and we wanted to better understand the prevalence of oral HPV infection in spouses of people who had HPV-related oropharyngeal cancer, to understand whether HPV is being transmitted among these couples and what the spouses' own cancer risk might be,” she said in an interview.
She and her colleagues collected oral rinse samples from 166 patients (147 male and 19 female) and 94 spouses or partners and tested them for HPV DNA. The prevalence of HPV in spouses was found to be similar to that in the general population; 65 percent of patients were infected with HPV at the time of diagnosis of their cancer, and 54 percent had the oncogenic HPV 16 variant. A year later, after treatment, the infection rate was very low: 5.6 percent.
And when partners were screened for oral cancers, none were found. The only indication of oncogenic HPV transmissibility was from five cases (3.8%) of male patients who reported having a current or previous partner who developed cervical dysplasia or cancer.
D'Souza said she presumed the spouses had been repeatedly exposed to oral HPV infection throughout their relationships but had been able to develop good immune responses and clear these infections.
“Most of us are exposed to HPV in our life, and although not all of us are exposed to the oncogenic strains, HPV infection is very common. Most of us are able to clear these infections on our own, and we think that's what's happening in our spouses,” she explained.
Lessons about Oropharyngeal Cancer & HPV Transmission
She said the study does support the idea that HPV can be transmitted to the mouth by oral sex—as suspected from other studies. “But it reassures us that—while caution with new sexual partners is always needed—in long established partnerships when one of the partners is diagnosed with HPV-related oropharyngeal cancer, these couples have likely swapped whatever they're going to swap over the course of the many years that they've been together and have cleared these infections.
“I'm hoping that this is very reassuring for our couples and that they do not need to change sexual intimacy in their established partnerships. Although of course for our single patients, caution with new partners is always advised,” she added.
D'Souza noted that although HPV-related oropharyngeal cancer is often stigmatized as a sexually transmitted disease-related cancer, HPV is a very common infection: “In fact half of our cases who developed this cancer had five or fewer lifetime oral sex partners. That is not a high-risk profile; this diagnosis does not in any way indicate a high-risk sexual profile or any infidelity on the part of the couple.
“Oral HPV infection is common, many people will develop infection but will clear it on their own, and most people with HPV do not develop cancer.”
The moderator of the news conference, Gregory A. Masters MD, Director of the Medical Oncology Fellowship and an attending physician at Christiana Care's Helen F. Graham Cancer Center in Delaware and a member of ASCO's Cancer Communications Committee, said that longer follow-up is needed, but that he recognized the HOTSPOT data as providing important information in the understanding of the biology of oropharyngeal cancer.
“I'm sure this news will provide long-awaited reassurances for patients as well as their spouses and partners.”