What is anal cancer?
Anal cancer is a rare cancer that develops in the tissues of the anal canal. In most cases it is linked to persistent infection with high-risk strains of the human papillomavirus (HPV). Anal cancer often begins as precancerous changes known as anal intraepithelial neoplasia, or AIN. Not all AIN progresses to cancer, but early detection and treatment greatly reduce the risk.
The symptoms of anal cancer can vary and are often mistaken for more common conditions such as haemorrhoids or fissures. Because early diagnosis improves outcomes, any persistent or unexplained symptoms should be reviewed by a colorectal surgeon.
What causes anal cancer?
The most common cause is long-standing infection with high-risk HPV. These strains can cause abnormal changes in the lining of the anal canal that may gradually progress to cancer if left untreated. Many people naturally clear HPV, but in some cases the virus persists and leads to ongoing cell changes.
Several factors can increase the risk of anal cancer. These include a history of AIN or genital dysplasia, previous anal warts, receptive anal intercourse, HIV infection, long-term immune suppression, previous HPV-related cancers, and increasing age. Most cases occur in adults over the age of 50. Anal cancer is not caused by poor hygiene, and many people diagnosed have no obvious risk factors.
What are the symptoms of anal cancer?
Symptoms depend on the size and position of the tumour. Many early symptoms resemble benign conditions. Common signs include bleeding from the anus, either during a bowel movement or on wiping, persistent pain or discomfort around the anus, and a lump or growth that may be felt near the anus. Persistent itching, irritation, or changes in bowel habits may also occur.
Unexplained symptoms that last for more than a few weeks should be assessed promptly.
Early diagnosis offers the best chance of successful treatment.
How is anal cancer diagnosed and treated?
Diagnosis usually involves an examination by a colorectal surgeon. Following the initial examination, specialist assessment often includes arranging high-resolution imaging, such as an MRI of the pelvis, to determine the exact size and spread of the tumour. This detailed imaging is crucial for accurate staging and treatment planning. The diagnostic journey is often managed by a multidisciplinary team (MDT), which includes oncologists, radiologists, and pathologists, ensuring every patient benefits from a combined expert perspective on their Anal Cancer management.
Treatment depends on the stage of the cancer.
Most early and intermediate stages are treated with chemoradiotherapy, which combines chemotherapy and radiotherapy to destroy the tumour while preserving the anal sphincter.
Surgery may be required if the cancer does not respond to treatment or if it returns.
Advanced cases may need additional therapies.
The primary goal of most anal cancer treatment is cure while preserving quality of life. After completion of primary treatment (chemoradiotherapy or surgery), patients require meticulous and regular follow-up for several years. This monitoring is vital to detect any recurrence early, which significantly improves long-term outcomes. Patients are also provided with support and resources to manage the side effects of treatment, including sexual health and continence issues, ensuring holistic care.
Regular follow-up is important to monitor healing and to detect any recurrence at an early stage.
When should you see a colorectal surgeon?
You should seek specialist assessment if you experience persistent anal bleeding, ongoing pain, a lump near the anus, or unexplained changes in bowel habits. People with AIN, previous anal warts, or long-standing HPV infection should have regular monitoring. Early specialist review is essential because anal cancer is highly treatable when identified early. Trusting a dedicated Anal Cancer team ensures the best clinical pathway and emotional support throughout your journey.