A biopsy is essential in diagnosing bladder cancer and occurs when a sample of abnormal-appearing bladder tissue is removed and examined under a microscope for cancer cells.
Information from the biopsy is used to determine the grade and stage of the cancer—and it’s these two key factors that help devise a patient’s treatment plan.
Obtaining a Bladder Biopsy
The first step for obtaining a bladder biopsy is undergoing a cystoscopy. This is then followed by a procedure called a transurethral resection of bladder tumor (TURBT).
Cystoscopy
A cystoscopy is performed in patients who are suspected of potentially having bladder cancer. This includes people with painless, microscopic blood in their urine who are age 35 years or older and/or have risk factors for bladder cancer.
During a cystoscopy, a urologist places a flexible, tube-like instrument with a light and a small video camera (called a cystoscope) through a patient’s urethra into their bladder. To better visualize the bladder, a saline (saltwater) solution is also injected into the bladder in order to fill and stretch it.
While examining the bladder, if a tumor or abnormal tissue is seen, the urologist will biopsy it. A doctor called a pathologist can then look at the sample under a microscope and determine if cancer cells are present.
Transurethral Resection of Bladder Tumor
If abnormal areas are seen on cystoscopy and/or a biopsy reveals cancer cells, then a patient will undergo a procedure called a transurethral resection of bladder tumor (TURBT) to definitively diagnose, grade, and help stage the cancer.
During a TURBT, a surgeon will use a thin, rigid instrument (called a resectoscope) that contains a wire loop. Like a cystoscope, the resectoscope will go through the urethra to reach the bladder.
The wire loop on the resectoscope is used to scrape any tumor from the bladder wall. In addition to removing the tumor, part of the bladder muscle located near the tumor will be taken out during a TURBT.
Interpreting Your Biopsy Results
Your TURBT biopsy results will report two key aspects of the cancer—grade and invasiveness.
Grade
The grade of the bladder cancer is based on what the cancer cells look like under the microscope.
There are two grades for bladder cancer:
Low-grade: These cancer cells resemble normal bladder cancer cells. High-grade: These cancer cells appear very abnormal and do not resemble typical bladder cancer cells.
Patients with low-grade bladder cancer tend to respond to treatment and do well. On the other hand, high-grade bladder cancer is harder to treat and more likely to recur and become invasive (see below).
Invasiveness
The invasiveness of the cancer refers to how deeply the cancer has extended or spread into the bladder muscle wall. There are two levels of invasiveness for bladder cancer:
Non-Invasive: The cancer has not spread into the muscle layer of the bladder (so it is contained within the inner lining of the bladder)Invasive: This type of cancer has spread into the muscle of the bladder (called the detrusor muscle).
Stage
Bladder cancer staging refers to how far the cancer has spread, and is a prime tool in helping doctors devise a treatment plan, as well as predict a patient’s prognosis (their chance of recovery).
The system most commonly used to stage bladder cancer is the TNM system.
T (Tumor): Describes whether the cancer has invaded into the bladder wallN (Node): Describes whether the cancer has spread to lymph nodes near the bladderM (Metastasis): Describes whether the cancer has spread to distant lymph nodes or organs
Letters or numbers combinations after T, N, and M provide more information about the cancer, with higher numbers and letters indicating a more advanced cancer (one that is harder to treat).
These TNM combinations are then grouped into five main stages:
Stage 0
This non-invasive cancer is found on the surface of the inner lining of the bladder. The cells are usually clumped together and easy to remove.
Stage 0is
This non-invasive cancer is a flat tumor found on the inner lining of the bladder. This is always a high-grade bladder cancer—so it’s generally difficult to treat and more likely to be invasive.
Stage I
This non-invasive cancer has grown through the inner lining of the bladder, but not into the muscle or to nearby lymph nodes or distant organs.
Stage II
This invasive cancer has spread into the muscle wall of the bladder.
Stage III
This invasive cancer has spread through the muscle wall of the bladder and into the fatty tissue that surrounds the bladder. The cancer might also have spread to the prostate in a man or uterus or vagina in a woman, as well as one or more nearby lymph nodes.
Stage IV
This invasive cancer has spread through the bladder wall into the pelvic or abdominal wall, and/or it has spread to distant lymph nodes or organs.
A Word From Verywell
If you or a loved one has undergone a bladder biopsy, it is normal to feel anxious or overwhelmed. You may worry about your results, and the waiting period (usually a few days) may seem like it goes on forever. Try to remain calm and seek out support and distraction from a partner, friend, or another family member during this difficult time.
Once you get your results, it’s OK to digest the information and ask lots of questions, especially if the diagnosis is cancer. After some processing time, you will then hopefully feel ready to move forward with your treatment plan.
