Staging of Anal Cancer
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 whether the cancer has spread within
the anus or to other parts of the body is called the stage. Information
collected from the stage determine 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 process of stage:
• CT scan: A procedure
that makes a series of detailed pictures of areas inside the body, taken from
different angles. The pictures are made by a computer linked to an x-ray
machine. Dye may be injected into a vein
or swallowed to help the organs or tissues show up more clearly. This procedure
is called computed tomography, computerized tomography, or computerized axial
tomography. For anal cancer, CT scan
of the pelvis and abdomen (stomach) may be performed.
• Chest X-rays: X-ray of the organs and bones inside the chest. X-ray is a type of energy beam that can pass through the body and onto film, making pictures of areas inside the body.
• Endo-anal or endorectal ultrasound: A procedure in which an
ultrasound transducer (probe) is inserted into the anus or rectum and used to
reflect the sound waves of high-powered (ultrasound) of the internal tissues or
organs and make echoes . Echoes form a picture of body tissues called a
sonogram.
There are three ways of spreading cancer in the body.
Three way cancer spreads in the body are:
• Through its network. Cancer invade surrounding normal tissue.
• Through the lymph system. Cancer attacks the lymph system and walk
through the lymph vessels to other places in the body.
• Through the blood. Cancer invades the veins and capillaries and
travels through the blood to other places in the body.
When cancer cells regardless of the primary tumor (origin) and walk
through the lymph or blood to other places in the body, other tumors
(secondary) may be formed. This process is called metastasis. Secondary tumors
(metastatic) cancer is the same type as the primary tumor. For example, if
breast cancer spreads to the bones, the cancer cells in the bones are actually
breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
The following stages are used for anal cancer:
Stage 0
In stage 0, cancer is found only in the innermost lining of the
anus. These abnormal cells may become cancer and spread into nearby normal
tissue. Cancer stage 0 is also called carcinoma in situ.
Stage I
In stage I, cancer has formed and the tumor is 2 centimeters or
smaller.
Stage II
In stage II, tumors larger than 2 centimeters.
Stage IIIA
In stage IIIA, the tumor may be any size and has spread to:
• lymph nodes near the rectum; or
• adjacent organs, such as the vagina, urethra, and bladder.
Stage IIIB
In stage IIIB, the tumor may be any size and has spread:
• to adjacent organs and to lymph nodes near the rectum; or
• to the lymph nodes on one side of the pelvis and / or groin, and
may have spread to adjacent organs; or
• to the lymph nodes near the rectum and in the groin, and / or to
lymph nodes on both sides of the pelvis and / or groin, and may have spread to
adjacent organs.
