Bladder Cancer Staging and Grading
There are two terms that patients should understand regarding the diagnosis and treatment of their cancer: staging and grading. These terms are used by the doctor when it comes to planning treatment, prescribing medications, deciding on surgical treatments or even estimating the likely long-term outcome or course of the disease.
Staging is a way to describe the extent or severity of an individual’s cancer. As the tumor develops, it can invade nearby organs and tissues, or cells can break off and enter the bloodstream or lymphatic system. The cancer then spreads (also called metastasizing) to form new tumors in other organs.
Doctors determine a cancer’s “clinical stage” by using a combination of physical examinations, imaging (such as CT or MRI scans), laboratory tests, biopsies, pathology reports and even physical symptoms a patient describes. If the tumor is removed, microscopic examination by the pathologist often reveals a more complete “pathologic stage”.
Although competing staging systems still exist for some types of cancer, the universally-accepted staging system is that of the “TNM Classification”. The “T” describes the size of the tumor and whether it has invaded nearby tissue, the “N” describes regional lymph nodes that are involved, and the “M” describes distant metastasis (spread of cancer from one body part to another).
Cancer grading (also called tumor grading) is a system used to classify the aggressiveness of cancer cells in terms of how abnormal they look under a microscope and how quickly the tumor is likely to grow and spread. This information can be obtained from a small sample (biopsy) of the tumor. However, as in staging, the information can be more accurate by microscopic examination of the entire tumor following complete removal. For most cancers, grades are described on a scale from 1 to 3 (or 4) from least to most aggressive. However, grading systems can be different for each type of cancer.
Bladder Cancer Staging:
T1 – tumor is confined to the bladder and has invaded the transitional epithelium but has not reached the level of the bladder muscle.
T2 – tumor is confined to the bladder but has penetrated into the muscle layer.
T2a – bladder tumor has penetrated the inner layer of muscle
T2b – bladder tumor has penetrated the outer layer of muscle
T3 – tumor has extended beyond the bladder wall to the perivesical fatty tissue that surrounds the bladder.
T3a – tumor cells can be observed only under a microscope (microscopic tumor)
T3b – tumor is visible with the naked eye (macroscopic tumor)
T4 – tumor has spread beyond the bladder and has invaded adjacent structures such as the prostate gland, uterus, vagina, abdominal wall, or pelvic wall.
T4a – bladder tumor invades the prostate gland or gynecological structures
T4b – bladder tumor invades abdominal or pelvic wall