Classifying Your Cancer
Pathology tests help to determine the cancer stage and grade — classifications that are essential to choosing the most effective cancer treatment and predicting how the disease will progress. The American Joint Committee on Cancer (AJCC) uses the TNM classification to define the stages of bladder cancer:
T is for Tumor
The number after the T indicates the size of the tumor and how far it has invaded. The larger the number, the bigger and/or more invasive the cancer.
- TX means a primary tumor cannot be assessed.
- T0 means no evidence of primary tumor.
- Ta means noninvasive papillary carcinoma.
- Tis means carcinoma in situ or “flat tumor”
- T1 means the tumor invades subepithelial connective tissue.
- T2 (both T2a and T2b) has invaded the muscle.
- T3 (both T3a and T3b) has invaded into the fat surrounding the bladder.
- T4 (both T4a and T4b) has invaded one or more of the following: prostate, seminal vesicles, uterus, vagina, pelvic wall or abdominal wall.
N is for Nodes
The number after the N indicates whether the cancer has spread to the lymph nodes.
- Nx means the regional lymph nodes cannot be assessed.
- N0 means there is no metastasis (spread) of the cancer to the local nodes.
- N1 means there has been metastasis to a single regional lymph node in the true pelvis.
- N2 means there is metastasis in multiple regional lymph nodes in the true pelvis.
- N3 means there has been metastasis to the common iliac lymph nodes.
M is for Metastasis
The number after the M indicates whether the cancer has spread to distant areas of the body.
- M0 means there is no distant metastasis.
- M1 means the cancer has metastasized to at least one site.
Staging and Grading Bladder Cancer
Another system for identifying the stages of bladder cancer uses Roman numerals from I to IV to define the extent of the disease. The definitions of these stages are as follows:
Stage refers to if and how far the disease may have spread.
- Stage 0: Cancer cells are found only on the surface of the inner lining of the bladder, also called carcinoma in situ.
- Stage I: The tumor has grown deeper into the inner lining of the bladder, but not the bladder’s muscle layer.
- Stage II: The tumor has invaded the muscle layer of the bladder.
- Stage III: The tumor has grown through the muscle layer to reach tissues near the bladder, such as the prostate, uterus or vagina.
- Stage IV: The tumor has invaded the wall of the pelvis or abdomen, but cancer is not found in any lymph nodes. Or, the cancer cells have spread to at least one lymph node or to parts of the body far away from the bladder, such as the liver, lungs, or bones.
Grade refers to how different from normal, the cancer cell appears. Higher grade cancers tend to grow faster and are more likely to spread.
- Low Grade – Cells given this grade appear fairly normal. Some cells may have increased in size. Some are multiplying.
- High Grade – High grade cells are very uneven in shape. They vary widely in size and all are multiplying.