Anal Cancer Stage II

Stage 2 anal cancer means the tumor has grown larger than 2cm but has not yet spread to nearby lymph nodes or other parts of the body. Understanding this stage helps doctors choose the most effective treatment approach.

Table of contents

• What is Stage 2 Anal Cancer?
• Stage 2A and Stage 2B
• TNM Staging System
• Treatment Options
• What Happens After Treatment

What is Stage 2 Anal Cancer?

Stage 2 anal cancer means the cancer is larger than 2cm and has not spread to any nearby tissue, lymph nodes, or other organs^[1]. The cancer remains in the anus (the opening at the end of the large intestine where stool leaves the body) or the anal canal (the short tube connecting the rectum to the anus)^[3].

Most anal cancers are squamous cell cancers, which start in the flat cells lining the anal canal^[1]. The information about stage 2 specifically applies to this most common type of anal cancer.

Stage 2A and Stage 2B

Stage 2 anal cancer is divided into two groups based on the size of the tumor^[1].

Stage 2A

In stage 2A, the cancer is larger than 2cm but no bigger than 5cm. It has not spread to any nearby tissues, lymph nodes, or other parts of the body^[1].

Stage 2B

In stage 2B, the cancer is larger than 5cm. Like stage 2A, it has not spread to any nearby tissues, lymph nodes, or other parts of the body^[1].

TNM Staging System

Doctors also use another staging system called the TNM system to describe anal cancer in detail^[1]. TNM stands for:

• T describes the size of the tumor
• N describes whether there are any cancer cells in nearby lymph nodes
• M describes whether the cancer has spread elsewhere in the body

The TNM system gives detailed information that is then combined into the simpler number staging system^[1].

For stage 2 anal cancer, the TNM descriptions are:

• Stage 2A is the same as T2, N0, M0 in the TNM system
• Stage 2B is the same as T3, N0, M0 in the TNM system

In both cases, N0 means no cancer in nearby lymph nodes, and M0 means no spread to other parts of the body^[1].

Treatment Options

Knowing the stage of cancer helps your doctor decide which treatment is best for you. Treatment can also depend on where the cancer is located in your anus and your general health^[1].

Chemoradiotherapy

The main treatment for stage 2 anal cancer is chemoradiotherapy, which means you have both chemotherapy and radiotherapy at the same time^[1][4].

Chemotherapy uses anti-cancer drugs to destroy cancer cells. These drugs are also called cytotoxic drugs, and they circulate throughout the body in the bloodstream^[1].

Radiotherapy uses high-energy waves similar to x-rays to kill cancer cells^[1]. It can also be called radiation therapy^[4].

During chemoradiotherapy, external radiation therapy is usually given once a day, 5 days a week, for 5 to 6 weeks. Chemotherapy is given every 3 weeks^[4]. The chemotherapy drug combination most commonly used is fluorouracil (also called 5-fluorouracil or 5-FU) and mitomycin. Sometimes capecitabine is used instead of fluorouracil^[4].

Extra radiation doses, called a radiation boost, may also be given^[4].

Chemoradiotherapy leaves the muscles of the anal sphincter (the ring-like muscles that control bowel movements) in place. If it is possible to avoid harming or removing these muscles, your overall quality of life after treatment will be better because you will be able to have bowel movements normally^[4].

Unfortunately, chemoradiotherapy is not suitable for everyone. Your doctor will talk to you about other options if they feel it is not the best treatment for you^[1].

Surgery

Some people diagnosed with anal cancer may have an abnormal opening or passage between the anus and the surrounding skin. This is called an anal fistula or perianal fistula. If you have an anal fistula, you will need surgery to repair it before you start chemoradiotherapy^[4].

What Happens After Treatment

When you have finished your treatment, your doctor will check that the cancer has completely gone^[1].

If your doctor thinks there is any cancer left after chemoradiotherapy, they will take a sample of tissue (biopsy) from the area. If this contains cancer cells, they will talk to you about further treatment^[1].

This may include a large operation called an abdominoperineal resection (APR). This is sometimes called salvage surgery because it is done to remove cancer that remains after initial treatment^[1][4]. The surgery removes the rectum, anal sphincter, anus, and muscles around the anus^[4].

Your surgeon and anaesthetist (a doctor who gives medicine to make you sleep during surgery) will make sure you are well enough to have this surgery^[1].