AJCC staging system

The AJCC staging system is a classification system developed by the American Joint Committee on Cancer for describing the extent of disease progression in cancer patients. It utilizes in part the TNM scoring system: Tumor size, Lymph Nodes affected, Metastases.

Cancers are classified at different stages depending on how advanced tumours have progressed. Staging describes the extent or severity of an individual's cancer based on the extent of the original (primary) tumor and the extent of spread in the body. Knowing the state of the disease helps the doctor plan a treatment and determine a prognosis (likely outcome or course of the disease). Staging provides a common language with which doctors can communicate about a patient's case. Knowing the stage is important in identifying clinical trials that may be suitable for a particular patient.

Staging is based on knowledge of the way cancer develops. Some staging systems cover many types of cancer; others focus on a particular type. For most cancers, the stage is based on three main factors:

Cancers of the brain and spinal cord are classified according to cell type and grade. Different staging systems are used for many cancers of the blood or bone marrow such as lymphoma.

Doctors gather different types of information about a cancer to determine its stage. The various tests used for staging depend on the type of cancer. Tests include the following:

There are three different types of staging:

The TNM Staging System is one of the most commonly used staging systems. This system was developed and is maintained by the American Joint Committee on Cancer (AJCC) and adopted by the Union for International Cancer Control (UICC). The TNM classification system was developed as a tool for doctors to stage different types of cancer based on certain standard criteria.

The TNM Staging System is based on the extent of the tumor (T), the extent of spread to the lymph nodes (N), and the presence of metastasis (M).

The T category describes the original (primary) tumor.

TX - Primary tumor cannot be evaluated

T0 - No evidence of primary tumor

Tis - Carcinoma in situ (early cancer that has not spread to neighboring tissue)

T1–T4 - Size and/or extent of the primary tumor

The N category describes whether or not the cancer has reached nearby lymph nodes.

NX - Regional lymph nodes cannot be evaluated

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