Cancer
Colon cancer is one of the most common forms of cancer in the United States, with more than 100,000 new cases diagnosed among men and women in 2009, according to the American Cancer Society. Although colon cancer starts the digestive system, it can spread to other nearby areas, including the lymph nodes.
Colon Cancer Staging System
The American Joint Committee on Cancer uses the TNM system to determine the extent of colon cancer in a patient. The T section indicates whether the primary tumor has spread into the wall of the intestines. The N section specifies if the tumor has spread to lymph nodes and how many it has affected. The M section indicates if the cancer has spread beyond the lymph nodes and metastasized to other parts of the body.
Lymph Node Cancer Diagnosis
Some doctors use a test called an endorectal ultrasound. In this test, a microphone called a transducer is inserted into the rectum, and sound waves are used to determine whether the cancer has spread through the wall of the colon to nearby lymph nodes and other parts of the body.
Positron Emission Tomography
Another test to diagnose whether colon cancer has spread to the lymph nodes is a positron emission tomography (PET) scan. A radioactive substance called fluorodeoxyglucose is injected into the body, and a special camera is used to image the body.
Colon Cancer N Categories
The N category of the TNM test specifies the extent to which the colon cancer has spread to the lymph nodes. The ratings are:
Nx - No diagnosis due to incomplete information.
N0 -- The cancer has not spread to any lymph nodes.
N1 - Cancerous cells have been detected in one to three nearby lymph nodes.
N2 - Cancerous cells have been detected in four or more nearby lymph nodes.
Colon Cancer Survival Rates
The National Cancer Institute places patients with a rating of N1 or N2 into the stage III A, B or C category for colon cancer. The five-year survival rate for patients with Stage III A, B or C colon cancer ranges from 44 to 83 percent, according to the NCI.
Tags: lymph nodes, cancer spread, spread lymph, spread lymph nodes, cancer spread lymph, nearby lymph, nearby lymph nodes
