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designated cancer center

Diagnosis and Treatment of Anal Cancer

Anal cancer affects the most distal 1 1/2" of the colon called the anus, the muscular sphincter, and anal structures that are outside the colon and are similar to skin tissues. It is a fairly rare type of cancer, affecting just over 4,000 people each year in the U.S. according to the American Cancer Society. Anal cancer usually occurs between the ages of 50 and 80. Other types of colorectal cancer can occur in conjunction with anal cancer.

Risk factors for anal cancer 

In many cases, anal cancer is believed to be linked to infection by the human papilloma virus (HPV), the same virus that causes many cases of cervical cancer in women. In fact, women who've had cervical cancer or cervical dysplasia (a precancerous cervical condition) are at increased risk of developing anal cancer.

Disease risk is also increased in smokers, and HIV-negative men who have sex with men. HIV-positive men who have sex with men are at an especially high risk of developing anal cancer because of their weakened immune systems, as are people with other long-term immunocompromising conditions. Smoking also greatly contributes to an increased risk of developing anal cancer.

Types of anal cancer

Because there are so many different cell types in the anus, multiple types of cancer can arise,  including:

Stanford Expertise

A Personalized, Team Approach

Patients with anal cancer are evaluated and treated by a team of physicians who participate in Stanford's multidisciplinary gastrointestinal-colorectal tumor board. This group of experts includes faculty with expertise in radiology, interventional radiology, radiation oncology, medical oncology, pathology, and gastroenterology. With all your doctors working together, you can be assured that all possible treatment approaches have been considered and the one that is best for you is put into place.

Prevention and Treatment

Stanford is fortunate to have on staff physician researchers who have demonstrated the relationship between the presence of HPV and anal cancer. In fact, Stanford physicians have developed approaches for monitoring patients at high risk of developing anal cancer due to HPV infection, and using preventive techniques to remove dangerous cells before they turn into cancer.

Furthermore, should you develop cancer, Stanford's colorectal cancer surgeons are among the best in the world, and have been in a leadership position in anal cancer treatment and follow-up regardless of the patient's HPV status.

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