Bladder cancer staging helps determine which treatment options should be pursued as well as your overall outlook.
If you receive a diagnosis of bladder cancer, your doctor will want to determine its stage.
There are two main ways to stage bladder cancer: the TNM system and the number system. Doctors use the TNM method most often but both are common. They can also be used together.
Let’s take a detailed look at how bladder cancer is staged.
The TNM system of bladder cancer staging assigns scores to three elements: the tumor (T), your lymph nodes (N), and metastasis (M).
T (tumor)
The first part of the TNM staging method describes the tumor. In general, higher numbers mean the cancer has spread through more layers of your bladder (starting on the inside and working out).
Here is a breakdown:
- T0: No evidence of cancer.
- Ta: The cancer cells have grown into the interior of your bladder. This is called a papillary tumor. It hasn’t spread from your bladder’s inner lining.
- Tis: This stands for “tumor in situ.” Alternatively, you might see CIS for “carcinoma in situ.” This means the cancer cells are a flat layer within your bladder’s inner lining.
- T1: The cancer has spread beyond your bladder’s inner lining to the connective tissue beyond, but it hasn’t reached the muscle layer.
- T2: The cancer has spread into the muscle layer but hasn’t reached the fatty tissue beyond. Sometimes it’s further divided:
- T2a: The tumor has only reached the inner muscle layer.
- T2b: The tumor has reached the outer muscle layer.
- T3: The cancer has spread into the fatty tissue layer. Sometimes it’s further divided:
- T3a: The cancer in the fatty tissue layer can only be seen under a microscope.
- T3b: The cancer in the fatty tissue layer can be seen without a microscope.
- T4: The cancer has spread beyond your bladder. Sometimes it’s further divided:
- T4a: The cancer has spread to your uterus, vagina, prostate, or bowel.
- T4b: The cancer has spread to areas other than those in T4a.
- TX: This means the main tumor can’t be checked.
N (node)
“Node” describes the state of the lymph nodes near your bladder. These are called regional lymph nodes. Your lymph nodes are part of your immune system. Higher numbers mean the cancer has spread to more lymph nodes.
Here is a breakdown:
- N0: There’s no cancer in the lymph nodes near your bladder.
- N1: The cancer has spread to one nearby lymph node.
- N2: The cancer has spread to multiple nearby lymph nodes.
- N3: The cancer has spread further, to the common iliac lymph nodes.
- NX: Your lymph nodes can’t be checked.
M (metastasis)
“Metastasis” describes whether the cancer has spread to other parts of the body.
Here is a breakdown:
- M0: The cancer hasn’t spread to other parts of your body.
- M1: The cancer has spread to other parts of your body. Sometimes it’s further divided:
- M1a: The cancer is limited to the lymph nodes beyond your pelvis.
- M1b: The cancer has spread beyond the distant lymph nodes to other parts of your body, like your lungs or liver.
Combinations
When doctors stage bladder cancer, they will stage the T, N, and M components together.
For example, you might receive a staging of “T1, N0, M0,” meaning the tumor hasn’t reached your bladder’s muscle layer (T1), and it hasn’t spread to your nearby lymph nodes (N0) or other parts of your body (M0).
Another common bladder cancer staging system is a number system, from 0 to 4. Roman or Arabic numerals may be used to designate these stages.
Stage 0 bladder cancer
- Stage 0A: The cancer cells have only grown into your bladder’s interior.
- Stage 0is: The cancer cells are a flat layer within your bladder’s inner lining.
Stage 1 bladder cancer
The cancer has grown beyond your bladder’s inner lining, but it hasn’t reached the muscle layer.
Stage 2 bladder cancer
The cancer has grown into your bladder’s muscle layer but not the fatty tissue layer.
Stage 3 bladder cancer
- Stage 3A: The cancer has grown into your bladder’s fatty tissue layer and may have spread to your uterus, vagina, prostate, bowel, or a single nearby lymph node.
- Stage 3B: The cancer has reached multiple nearby lymph nodes or the common iliac lymph nodes.
Stage 4 bladder cancer
- Stage 4A: The initial tumor has spread further than the areas listed in stage 3 or has spread to distant lymph nodes.
- Stage 4B: The cancer has spread beyond the distant lymph nodes to other parts of your body, such as your lungs or liver.
Number stages compared to TNM stages
Number stage | T (tumor) | N (node) | M (metastasis) |
---|---|---|---|
stage 0a | Ta | N0 | M0 |
stage 0is | Tis (CIS) | N0 | M0 |
stage 1 | T1 | N0 | M0 |
stage 2 | T2 | N0 | M0 |
stage 3A | T3a, T3b, or T4a | N0 | M0 |
stage 3A | T1–T4a | N1 | M0 |
stage 3B | T1–T4a | N2–N3 | M0 |
stage 4A | T4b | any | M0 |
stage 4A | any | any | M1a |
stage 4B | any | any | M1b |
Some specific stages of bladder cancer have unique terms to describe them, but they do still fit somewhere within the TNM and number staging systems.
Non-muscle invasive bladder cancer
Non-muscle invasive bladder cancer (NMIBC) is any bladder cancer that hasn’t reached your bladder’s muscle layer. This includes any T number below 2 or a stage number below 2.
Muscle-invasive bladder cancer
Muscle-invasive bladder cancer is any bladder cancer that has reached your bladder’s muscle layer. This includes any T number of 2 or greater or stage 2 bladder cancer or higher.
Metastatic bladder cancer
Once bladder cancer has spread further in your body, it’s considered metastatic. This includes a T4b rating or any M number greater than 0. It’s considered stage 4 bladder cancer.
Generally, the earlier cancer is found, the better the outlook, and this applies to bladder cancer.
While your circumstances will be unique to you, there are some statistics available that describe the 5-year relative survival rates of bladder cancer depending on the stage at the time of diagnosis.
According to the
- In situ: For bladder cancer that’s Tis (CIS) or stage 0is, the 5-year relative survival rate is 96%.
- Localized: For bladder cancer that hasn’t left the bladder (T less than 4, N0, M0; or stage 0 through some stage 3A), the 5-year relative survival rate is 69.6%.
- Regional: For bladder cancer that’s spread to the nearby lymph nodes (T less than 4, N less than 3, M0; or stage 0 through some stage 3A and 3B), the 5-year relative survival rate is 39%.
- Distant: For bladder cancer that’s metastasized (M greater than 0, or stage 4), the 5-year relative survival rate is 7.7%.
Keep in mind that these statistics are from 2012 to 2018 in the United States and cannot tell you your unique outlook. Only your doctor and cancer care team will know your outlook.
There are many ways to describe the stages of bladder cancer, but they’re all based on how far the cancer has spread, either within your bladder or beyond.
The TNM and number staging methods are both commonly used and describe the same thing. Some important milestones, such as whether the cancer has reached your bladder’s muscle layer, can have their own names as well.