The short answer
Anal cancer is an uncommon cancer of the anus, often linked to the human papillomavirus (HPV). Symptoms can include bleeding, a lump, or discomfort, which are far more often caused by common conditions like hemorrhoids. Many anal cancers are treated successfully with combined chemotherapy and radiation.
Anal cancer is uncommon and often linked to HPV.
Symptoms like bleeding or a lump are usually caused by benign conditions.
Any lasting anal bleeding, lump, or change should be checked.
Treatment is often chemotherapy combined with radiation, avoiding surgery for many.
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The full explanation.
What anal cancer is
Anal cancer starts in the anus, the opening at the end of the digestive tract. It is uncommon. Most anal cancers are a type called squamous cell carcinoma, and many are linked to long-term infection with certain types of the human papillomavirus (HPV).
Symptoms
Symptoms can include bleeding, a lump or swelling near the anus, itching, pain, or a change in bowel habits. Importantly, these same symptoms are far more often caused by common, harmless conditions such as hemorrhoids or fissures. That overlap can delay diagnosis, so any anal bleeding, lump, or change that lasts should be examined.
Risk factors
Because HPV is a major factor, things that raise HPV exposure or weaken the immune system can raise risk. Smoking also increases risk. HPV vaccination, which protects against the virus types most linked to these cancers, lowers the risk of HPV-related cancers when given before exposure.
Diagnosis and treatment
Diagnosis involves an examination and a biopsy, with imaging to work out the stage. A major point of hope is that many anal cancers respond well to a combination of chemotherapy and radiation, which can treat the cancer while avoiding major surgery for many people. The plan depends on the stage.
Words to know
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Common questions
▸What causes anal cancer?
Many anal cancers are linked to long-term infection with certain types of HPV. Smoking and a weakened immune system also raise risk.
▸What are the symptoms?
Bleeding, a lump near the anus, itching, pain, or a change in bowel habits — though these are far more often caused by hemorrhoids or other benign conditions.
▸Is anal cancer treatable?
Yes. Many anal cancers respond well to combined chemotherapy and radiation, which can avoid major surgery for many people.
▸Can HPV vaccination help?
HPV vaccination lowers the risk of HPV-related cancers, including anal cancer, when given before exposure to the virus.
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