What is a prostate biopsy and why is it needed?
A prostate biopsy is a key procedure for the accurate histological diagnosis of prostate cancer [3]. It is an invasive test in which small samples of prostate tissue are taken for subsequent microscopic analysis. Despite the development of new imaging techniques and blood tests such as prostate-specific antigen (PSA), a biopsy remains the only way to confirm or rule out the presence of malignant cells [1].
Often, symptoms related to the prostate can be caused by benign prostatic hyperplasia (BPH)—a non-malignant enlargement of the prostate that occurs in aging men and causes bothersome lower urinary tract symptoms (LUTS) [2, 4, 7]. However, because the symptoms of BPH and prostate cancer can be similar, a biopsy is necessary for differential diagnosis and determining treatment tactics.
When is a prostate biopsy prescribed?
The main indications for a prostate biopsy are:
- Elevated blood PSA levels: Although PSA is not a cancer-specific marker (its levels can also rise with BPH and inflammation), a persistent or progressive increase requires further evaluation [1].
- Suspicious findings on a digital rectal exam (DRE): Detection of indurations or nodules in the prostate gland.
- Suspicious imaging changes: For example, detected via magnetic resonance imaging (MRI) or transrectal ultrasonography (TRUS) [1].
Despite the significance of PSA and new imaging methods, determining exact indications for biopsy and repeat biopsies remains a complex task [1].
Preparation for the biopsy procedure
Proper preparation for a prostate biopsy is crucial to minimize risks and obtain accurate results. Doctors generally recommend the following steps:
- Antibiotic prophylaxis: To prevent infectious complications that may occur when the needle passes through the rectum, a course of antibiotics is usually prescribed before and/or after the procedure [1].
- Medication adjustment: It is necessary to inform your doctor about all medications you are taking, especially those that affect blood clotting (such as anticoagulants or antiplatelet agents). In some cases, temporary discontinuation of these drugs may be required [5].
- Bowel cleansing: An enema may be recommended before the procedure.
- Preoperative ultrasound examination: An ultrasound before the biopsy is necessary to assess the size and morphology of the prostate gland and to plan a safe needle insertion trajectory [5].
How is a prostate biopsy performed?
A prostate biopsy is usually performed under ultrasound guidance, allowing the doctor to precisely view the prostate gland and guide the needle [1, 5]. The procedure can be performed using two main approaches [3]:
- Transrectal approach: The needle is inserted through the wall of the rectum. This is the most common method [1, 3].
- Transperineal approach: The needle is inserted through the skin of the perineum (the area between the scrotum and anus). This method may have certain advantages in specific clinical situations [3].
The procedure is performed under local anesthesia to reduce discomfort [5]. A specialized spring-loaded needle is used to quickly take a small tissue sample [5]. Historically, prostate biopsies were performed by urologists, but with the advent of imaging techniques, radiologists are increasingly involved in the procedure [3].
Depending on the situation, the doctor may perform:
- Sextant biopsy: Taking 6 samples from different areas of the prostate gland if no visible lesions are present [1].
- Targeted biopsy: Taking samples from specific suspicious areas detected by ultrasound or MRI, often in addition to a sextant biopsy [1].
When cancer cells are not detected, it may indicate benign changes such as BPH [7]. In this case, treatment will aim to relieve symptoms associated with prostate enlargement, for example, using medications that reduce prostate size, such as finasteride [2, 4].
Interpretation of biopsy results
The obtained tissue samples are sent to the laboratory for histological examination. A pathologist examines them under a microscope to determine the presence of cancer cells, their type, and their grade (aggressiveness) [1, 3].
Biopsy results allow to:
- Confirm or rule out prostate cancer: This is the primary result that determines further management.
- Evaluate tumor differentiation (Gleason score): This scale helps determine cancer aggressiveness and its potential to spread [1].
- Determine the stage of the disease: Combined with other tests, the biopsy helps stage the cancer, which is important for choosing treatment [1].
Potential risks and complications
Like any invasive procedure, a prostate biopsy carries certain risks, although it is considered safe [1]. The primary complication is bleeding [5]. Blood in the urine, stool, or semen may occur and usually resolves on its own. Infectious complications requiring additional treatment are less common. A structured observation period is required after the procedure [5].
Sources
- Considerations regarding prostate biopsies.
- Finasteride for benign prostatic hyperplasia.
- The role of urology and radiology in prostate biopsy: current trends and future perspectives.
- Risk stratification for benign prostatic hyperplasia (BPH) treatment.
- Ultrasound-guided kidney biopsy: a review of what operators need to know.
- WATER II (80-150 mL) procedural outcomes.
- Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART I-Initial Work-up and Medical Management.
Disclaimer: The information provided in this article is for reference purposes only and does not constitute medical advice or a guide to self-treatment. Always consult a qualified physician for diagnosis and treatment.