Cervical cancer linked to increased anal cancer risk

Researchers from the Medical University of South Carolina (MUSC) Hollings Cancer Center have identified cervical cancer as a potential risk factor of future anal cancer, publishing their findings in JAMA Network Open.¹

While anal cancer screening is recommended in organ transplant recipients, people living with HIV, and women with a history of vulvar cancer, screening guidelines have not been established for women with cervical cancer. This data highlights a nearly 2-fold increased risk of anal cancer in this population, potentially influencing future guidelines.¹

“We’ve known for a long time that both cervical and anal cancers are caused by HPV, the human papillomavirus,” said Haluk Damgacioglu, PhD, study lead and assistant professor at MUSC. “But what hasn’t been well-understood is how that shared risk might connect the 2 diseases over a woman’s lifetime.”¹

Cervical and anal cancer incidence rates

The cohort study was conducted to estimate anal cancer incidence since cervical cancer diagnosis.² Data was obtained from the National Cancer Institute’s Surveillance, Epidemiology, and End Results registries. International Classification of Disease for Oncology codes were referenced to determine cancer cases.

Women receiving an anal cancer diagnosis before or within 2 months of cervical cancer diagnosis were excluded from the analysis. A multiple primary standardized incidence ratios session was utilized to calculate overall, age-specific, and time since diagnosis-specific incidence rates (IRs) per 100,000 person-years.²

There were 822,630 person-years of follow-up across 85,524 cervical cancer patients diagnosed from 1975 to 2021 evaluated. In the study population, 64 anal cancer diagnosis cases were identified, indicating an overall incidence of 7.8 per 100,000 person-years.²

Age- and time-based differences

Differences in anal cancer incidence rates were highlighted across age groups and time since cervical cancer diagnosis. An IR of 2.4 was reported for women aged under 45 years with a history of cervical cancer but rose to 4.6 for those aged 45 to 54 years and 10.0 for those aged 54 to 64 years.²

Women aged 65 to 74 years presented with the greatest IR of 17.6, while those aged at least 75 years had an IR of 10.0. When assessing the incidence based on time since cervical cancer diagnosis, an IR of 5.8 was reported in the first 5 years. Additional IRs included 5.1 for 5 to 10 years, 12.7 for 10 to 15 years and 16.1 for 20 or more years.²

Of anal cancer diagnoses in women aged 65 to 74 years, 59% occurred over 15 years following cervical cancer diagnosis. Overall, a standardized incidence ratio of 1.9 was reported for anal cancer, with elevated risk persisting over time following cervical cancer diagnosis. This indicated a significant increase in risk among cervical cancer patients.²

Implications

Cervical cancer has a survival rate of over 90% when found early thanks to routine screening and the HPV vaccine.¹ However, this is one of the first studies to evaluate potential next steps in these patients who may experience elevated risks of related cancers.

“We don’t have the resources to screen everyone,” said Deshmukh. “But we can use these data to be strategic. Screening based on risk ensures we help the people who need it most.”¹

References

1. New study reveals a hidden risk after cervical cancer. Medical University of South Carolina. September 11, 2025. Accessed September 11, 2025. https://www.eurekalert.org/news-releases/1097373?
2. Damgacioglu H, Curtis C, Sonawane K, et al. Anal cancer incidence among women with a history of cervical cancer by age and time since diagnosis. JAMA Network Open, 2025;8(9). doi:jamanetworkopen.2025.31362