Second primary anal and oropharyngeal cancers in cervical cancer survivors

Abstract Background Human papilloma virus (HPV) infection is responsible for approximately 31,500 new cancers in the United States annually. Almost all cervical cancers are linked to HPV infection. As early identification and treatment of cervical cancer improve, the incidence of cervical cancer has decreased and survival has improved. However, survivors continue to remain at risk for other HPV-related malignancies. The purpose of this study is to assess the risk of primary anal and oropharyngeal cancers among women with a history of squamous cell carcinoma of the cervix. Study Design A population-based cohort of 21,060 women diagnosed with cervical squamous cell carcinoma from 1973-2014 was identified from the Surveillance, Epidemiology and End Results Program data (SEER 9). Standardized incidence ratios (SIR) for anal and oropharyngeal cancers were calculated to estimate the risk of a second primary HPV-related malignancy based on incidence in the general population. Results were further stratified by age (20-53, 54+ years old) and latency period (2-11, 12-59, 60-119, 120+ months). The number needed to screen (NNS) for oropharyngeal and anal cancers was estimated using study results and CDC reported incidence rates. Results Cervical squamous cell cancer survivors had a higher risk of being diagnosed with oropharyngeal cancer (SIR 4.36, 95% CI 1.19-11.15) and anal cancer (SIR 2.20, 95% CI 1.28-3.52). Patients diagnosed with cervical cancer between ages 20-53 had an increased risk of anal cancer (SIR 3.53, 95% CI 1.15-8.23). Age 54+ at cervical cancer diagnosis was associated with increased oropharyngeal cancer risk only (SIR 5.04, 95% CI 1.37-12.91). Latency stratification was only significant at 120+ months, at which time there was an increased risk of both oropharyngeal cancer (SIR 7.97, 95% CI 2.17-20.42) and anal cancer (SIR 2.60, 95% CI 1.34-4.54). The estimated NNS for oropharyngeal cancer (NNS OPC 282) and anal cancer (NNS anal 1272) is significantly less than the NNS for cervical cancer. Conclusion Squamous cell cervical cancer survivors have a substantially increased risk of anal and oropharyngeal cancers. This increased risk is significant 10 or more years after the cervical cancer diagnosis. Health care providers and survivors should be aware of this increased risk. The development of effective and economical surveillance methods for anal and oropharyngeal cancers in cervical cancer survivors is urgently needed.