Survivors of index squamous cell carcinoma of the anus faced an increased risk for subsequent HPV–related cancers, according to a cohort study published in Cancer.
“Over the last decade, HPV has been identified, associated with and found to be the main etiologic agent in cancer of the oropharynx and anogenital regions of men and women,” Rebecca A. Nelson, PhD, staff scientist in the department of information sciences, and Lily L. Lai, MD, associate cancer center director, both from City of Hope, wrote. “With the risk [for] cancer resulting from HPV infection, the lifestyle factors associated with this infection and the correlation of HPV infection at one site with HPV infection at other sites, patients diagnosed with one HPV–related cancer may be at an increased risk [for] developing HPV–related second primary malignancies.”
The researchers used the SEER database to identify 10,537 patients who had been diagnosed with squamous cell carcinoma of the anal canal from 1992 through 2012. Lai and Nelson used standardized incidence ratios to calculate patients’ excess risk for second HPV–related cancers.
HPV–related second cancers occurred in 416 patients (overall standardized IR = 21.5; 99% CI, 19-24.2). Men had a higher standardized incidence ratio for second cancers than women (35.8; 95% CI, 30.7-41.6 vs. 12.8; 99% CI, 10.4-15.5), and also showed a higher incidence ratio for second squamous cell carcinoma of the anus (127.5; 99% CI, 108.1-149.2 vs. 47; 99% CI, 34.7-62.1).
However, both men and women showed elevated standardized incidence ratios for oral cavity and pharyngeal cancers (3.1; 99% CI, 1.5-5.7 vs. 4.4; 99% CI, 1.5-9.7).
Risk for cancers at “sex-specific sites” also appeared elevated: Male genital cancers showed a standardized incidence ratio of 19.6 (99% CI, 8.7-37.6), and female genital cancers had an incidence ratio of 8.3 (99% CI, 6.1-11).
“Patients with a history of anal cancer have higher rates of HPV–related second primary malignancies,” Nelson and Lai wrote. “This risk is significant in men and women across all HPV–related sites. Because squamous cell carcinoma of the anus often presents early and treatment is effective, the extended survival rates likely impact the development of second primary malignancies. Further studies are needed to determine the benefits of systematic screening and surveillance programs for patients with an index anal cancer.” – by Andy Polhamus
Disclosure: The researchers report no relevant financial disclosures.