Anal Cancer

Anal Cancer

Stages of Anal Cancer

Key Points

  • After anal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the anus or to other parts of the body.
  • There are three ways that cancer spreads in the body.
  • Cancer may spread from where it began to other parts of the body.
  • The following stages are used for anal cancer:
    • Stage 0
    • Stage I
    • Stage II
    • Stage III
    • Stage IV

After anal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the anus or to other parts of the body.

The process used to find out if cancer has spread within the anus or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The following tests may be used in the staging process:

  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the abdomen or chest, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography. For anal cancer, a CT scan of the pelvis and abdomen may be done.
  • Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
  • Pelvic exam: An exam of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. A speculum is inserted into the vagina and the doctor or nurse looks at the vagina and cervix for signs of disease. A Pap test of the cervix is usually done. The doctor or nurse also inserts one or two lubricated, gloved fingers of one hand into the vagina and places the other hand over the lower abdomen to feel the size, shape, and position of the uterus and ovaries. The doctor or nurse also inserts a lubricated, gloved finger into the rectum to feel for lumps or abnormal areas.Pelvic exam; drawing shows a side view of the female reproductive anatomy during a pelvic exam. The uterus, left fallopian tube, left ovary, cervix, vagina, bladder, and rectum are shown. Two gloved fingers of one hand of the doctor or nurse are shown inserted into the vagina, while the other hand is shown pressing on the lower abdomen. The inset shows a woman covered by a drape on an exam table with her legs apart and her feet in stirrups. Pelvic exam. A doctor or nurse inserts one or two lubricated, gloved fingers of one hand into the vagina and presses on the lower abdomen with the other hand. This is done to feel the size, shape, and position of the uterus and ovaries. The vagina, cervix, fallopian tubes, and rectum are also checked.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if anal cancer spreads to the lung, the cancer cells in the lung are actually anal cancer cells. The disease is metastatic anal cancer, not lung cancer.

Many cancer deaths are caused when cancer moves from the original tumor and spreads to other tissues and organs. This is called metastatic cancer. This animation shows how cancer cells travel from the place in the body where they first formed to other parts of the body.

The following stages are used for anal cancer:

Stage 0

In stage 0, abnormal cells are found in the mucosa (innermost layer) of the anus. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called high-grade squamous intraepithelial lesion (HSIL).

Drawing shows different sizes of a tumor in centimeters (cm) compared to the size of a pea (1 cm), a peanut (2 cm), a grape (3 cm), a walnut (4 cm), a lime (5 cm), an egg (6 cm), a peach (7 cm), and a grapefruit (10 cm). Also shown is a 10-cm ruler and a 4-inch ruler.Tumor sizes are often measured in centimeters (cm) or inches. Common food items that can be used to show tumor size in cm include: a pea (1 cm), a peanut (2 cm), a grape (3 cm), a walnut (4 cm), a lime (5 cm or 2 inches), an egg (6 cm), a peach (7 cm), and a grapefruit (10 cm or 4 inches).

Stage I

In stage I, cancer has formed and the tumor is 2 centimeters or smaller.

Stage II

Stage II anal cancer is divided into stages IIA and IIB.

  • In stage IIA, the tumor is larger than 2 centimeters but not larger than 5 centimeters.
  • In stage IIB, the tumor is larger than 5 centimeters.

Stage III

Stage III anal cancer is divided into stages IIIA, IIIB, and IIIC.

  • In stage IIIA, the tumor is 5 centimeters or smaller and has spread to lymph nodes near the anus or groin.
  • In stage IIIB, the tumor is any size and has spread to nearby organs, such as the vagina, urethra, or bladder. Cancer has not spread to lymph nodes.
  • In stage IIIC, the tumor is any size and may have spread to nearby organs. Cancer has spread to lymph nodes near the anus or groin.

Stage IV

In stage IV, the tumor is any size. Cancer may have spread to lymph nodes or nearby organs and has spread to other parts of the body, such as the liver or lungs.

Disclaimer The content used in the pages is sourced from the National Cancer Institute Website ( www.cancer.gov )
Content Details Source URL : https://www.cancer.gov/types