Canal cancer

Anal and perianal tumors are relatively rare in clinical practice, accounting for less than 2% of colorectal and rectal tumors. Anal cancer is about three times more common than perianal cancer. Perianal cancer is more common in men than in women. The diagnosis of anal carcinoma mainly depends on digital examination and biopsy.

The cause of
The true cause of anal cancer is still unknown, but studies have shown that it is caused by the loss of control of multiple genes under the action of multiple factors, and long-term chronic stimulation such as anal fistula, condyloma and immune diseases are also related to the occurrence of anal cancer.

Clinical manifestations of
The early symptoms of anal cancer are not obvious, and the clinical manifestations in the progressive stage are similar to the lower rectal cancer, mainly including the following aspects:
1. Change of defecation habit, increase of defecation frequency, often accompanied by tenesmus or defecation insufficiency.
2. Fecal properties change, and fecal strips become thinner or deformed, often with mucus or pus blood.
3. Anal pain is the main feature of anorectal cancer. At the beginning, anal discomfort gradually worsens to continuous pain, which is more obvious after defecation.
4. Anal itching with secretions. Because anal cancer secretions stimulate perianal skin, patients with anal itching. Secretions with a foul smell.
5. Mass in anal canal, rectal digital examination or anal speculum examination can show ulcerative mass, polypoid mass and fungiform mass in anal canal, or infiltrating mass with anal canal constriction.
6. Inguinal lymphadenopathy, which may involve one or both inguinal lymph nodes, multiple, firm, or painful.

check
The diagnosis of anal carcinoma mainly depends on digital examination and biopsy. Early digital rectal examination is easy to detect lesions. Biopsy is the main basis for definite diagnosis, which can be divided into anal squamous cell carcinoma and adenocarcinoma. Digital rectal examination, intra-anal ultrasound examination and cytological biopsy of swollen lymph nodes are helpful to determine the stage of tumor. Liver ultrasound, lung X - ray and CEA examination can exclude distant metastasis.