|Classification and external resources|
Anal cancer is a type of cancer in the anus. It is caused by colorectal cancer. The etiology, risk factors, clinical progression, staging, and treatment are all different. Anal cancer is mostly a squamous cell carcinoma that rises near the squamocolumnar area.
In the United States, it is estimated that in 2014 about 7,060 new cases of anal cancer would be diagnosed in the United States (4500 in women and 2,500 in men) . It is typically found in adults, average age early 60s.