Technology to detect early signs of bladder cancer includes urinalysis to find blood in the urine, the examination of urine under a microscope known as urine cytology, and a number of other urine lab tests that look for tumor markers, reports the American Cancer Society. If doctors suspect bladder cancer, the next step is usually a cystoscopy, in which a urologist slides a tube up the urethra so the doctor can see the inside of the bladder.
Because most people do not undergo routine screening tests, the first signs of bladder cancer are usually blood in the urine or other urination problems, explains the American Cancer Society. Lab tests often give indications of the presence of cancer but are not conclusive. For cystoscopy, doctors may use local or general anesthesia. Once the cystoscope reaches the bladder, the urologist injects sterile salt water into the bladder to expand it and improve visibility. If the doctor detects an abnormality, he threads an instrument through the cystoscope to remove a small sample for a biopsy.
If the biopsy detects the presence of cancer, further tests measure its invasiveness and whether it is low-grade or high-grade, according to the American Cancer Society. These include needle biopsy or the biopsy of tissue removed during surgery. Imaging tests such as X-rays, CT scans, MRI scans, ultrasounds and bone scans locate the cancer and measure its spread.