Risk of anal cancer twice as high for cervical cancer survivors

Anoscopy is the direct visualization of the anus using a speculum. It is used to screen, diagnose, and evaluate perianal and anal problems. Image credit – Nurses Zone website.

CANCER DIGEST – Sept. 14, 2025 – A new analysis of cancer data shows that compared to the general population, women with a history of cervical cancer have nearly twice the risk of anal cancer.

The study led by Drs. Haluk Damgacioglu and Ashish Desshmukh, researchers at the Medical University of South Carolina, analyzed data in SEER, (Surveillance, Epidemiology and End Results) the national cancer registry maintained by National Cancer Institute to track cancer diagnoses in the U.S.

The researchers tracked 85,524 women diagnosed with cervical cancer over more than 20 years to see how many went on to develop anal cancers, and when those diagnoses occurred. The results appear in the Sept. 11, 2025 journal JAMA Network.

Cervical cancer and anal cancer both are often caused by HPV (human papillomavirus), but how one diagnosis affects the risk of the other has not been well understood. One challenge in answering that question has been a lack of long-term data on risk and how that risk changes with age and over time. Having that data in SEER made this type of analysis possible.

“We’ve known for a long time that both cervical and anal cancers are caused by HPV, the human papillomavirus,” Deshmukh said in a press release. “But what hasn’t been well-understood is how that shared risk might connect the two diseases over a woman’s lifetime.”

Currently, only people with HIV, or who have had an organ transplant, and women with vulvar cancer are screened for anal cancer.  What the researchers found was that anal cancer rates increased with age, with most diagnoses found in women 65-74 who were more than 15 years past their original cervical cancer diagnosis. The rate for this group of women was 17 cases per 100,000, a risk that far surpassed the generally accepted guideline for recommending routine screening.

“Our study shows that the risk (of anal cancer) doesn’t go away – it actually increases with age and over time,” said Damgacioglu.“It’s a slow process and that’s part of why it’s been so hard to detect. By the time symptoms show up, the cancer is often advanced.”

The researchers note that while anal cancer screening is not as routine as cervical cancer, for example, there are reliable methods for doing so, such as anal cytology and a specialized imaging tool called anoscopy. The catch is that such specialized screening is limited. In South Carolina, for example, there is only one provider trained to perform high-resolution anoscopy. Consequently, the importance of this study is that it helps identify and prioritize screening in the highest risk groups.

“These results tell us that women who had cervical cancer years ago should be considered for routine anal cancer screening,” Damgacioglu said. “Right now, that’s not happening.”

The researchers are beginning a new project in collaboration with MD Anderson Cancer Center that will evaluate how to best screen for this group of women. In the meantime, they hope their study will spur conversations between doctors and cervical cancer survivors.

Sources: Medical University of South Carolina press release and the journal JAMA Network