BPH is commonly diagnosed when its symptoms begin to interfere with daily life, but the doctor may also find an enlarged prostate during a routine checkup. The symptoms of BPH can be very much like those caused by prostate cancer and other serious conditions. So, further testing may be needed. A doctor can use a gloved finger in the rectum to check the prostate size and for small, hard lumps that might suggest prostate cancer. The doctor may also order a prostate-specific antigen, also known as a PSA, blood test. If this value is abnormal, the doctor may next order a biopsy sample of the prostate to look for prostate cancer.
Other tests may be done in certain cases. These may include measuring the rate of urine flow and checking with a catheter or special X-ray test to see how much urine is left in the bladder after voiding. A pressure-flow study combines measuring the urine flow and the pressure in the bladder during voiding. Cystoscopy is a procedure that uses a tiny telescope to look inside the urethra, prostate, and bladder for the amount of blockage. Ultrasound, a type of X-ray test, may be used to measure the exact size of the prostate. This can be important in making choices about therapy. A symptom questionnaire can help to measure both the symptoms and the response to treatment. Although some of the symptoms of BPH and prostate cancer are the same, BPH does not increase the chance of prostate cancer.