A prostate biopsy is a medical procedure used to diagnose prostate conditions, including prostate cancer. It involves taking small tissue samples from the prostate gland, typically guided by ultrasound or MRI, to examine under a microscope.

This procedure is often recommended when abnormal results are detected during a prostate-specific antigen (PSA) test or a digital rectal exam (DRE). While minimally invasive, a prostate biopsy is a critical tool for determining the presence of cancerous or other abnormal cells, aiding in early diagnosis and effective treatment planning.

What is prostate biopsy?

A prostate biopsy is a diagnostic procedure in which small samples of tissue are taken from the prostate gland to be examined under a microscope. This is typically done to detect or rule out prostate cancer or other abnormalities in the prostate.

A prostate biopsy helps pathologists identify whether cancerous or non-cancerous conditions are affecting the prostate, guiding appropriate treatment decisions. While generally safe, potential risks include minor bleeding, infection, or temporary discomfort.

How to do prostate biopsy?

A prostate biopsy is typically performed in a clinical setting and involves the following steps:

1. Preparation

• The doctor may prescribe antibiotics before the procedure to reduce infection risk.
• Patients may be asked to avoid blood-thinning medications like aspirin or warfarin.
• Some doctors recommend an enema beforehand to empty the rectum.

2. Anesthesia

• Local anesthesia is commonly used to numb the area and minimize discomfort.
• In some cases, sedation or general anesthesia might be used, especially for MRI-guided biopsies.

3. Positioning

• The patient usually lies on their side with knees pulled up toward the chest or lies on their back with legs elevated, depending on the biopsy method.

4. Tissue Sampling

• Multiple tissue samples (usually 10–12 or more) are taken from different areas of the prostate to ensure a comprehensive evaluation.

Consulting a urologist for detailed preparation and post-procedure instructions is essential for a safe and effective biopsy.

Indications

A prostate biopsy is typically indicated when there is a suspicion of prostate cancer or other prostate abnormalities based on the following factors:

1. Elevated PSA Levels

• Persistent or significantly high levels of prostate-specific antigen (PSA) in the blood.
• A rapidly rising PSA level (PSA velocity) or an abnormally high percentage of free PSA.

2. Abnormal Digital Rectal Exam (DRE)

• Detection of irregularities such as lumps, hard areas, or asymmetry in the prostate during a DRE.

3. Imaging Abnormalities

• Suspicious findings on multiparametric MRI or transrectal ultrasound (TRUS) that suggest potential cancerous changes.

4. Family or Genetic Risk Factors

• A strong family history of prostate cancer, especially in first-degree relatives.
• Genetic predispositions, such as BRCA1/BRCA2 mutations or Lynch syndrome.

5. Follow-Up After Treatment or Monitoring

• Monitoring individuals with a history of prostate cancer or those undergoing active surveillance for low-risk prostate cancer.

6. Persistent Symptoms

• Unexplained lower urinary tract symptoms, such as difficulty urinating or frequent urination, when other evaluations point to a potential prostate issue.

7. Evaluation of Atypical Findings

• Previous biopsy results showing atypical small acinar proliferation (ASAP) or high-grade prostatic intraepithelial neoplasia (HGPIN) warrant further evaluation.

8. Staging or Risk Assessment

• To determine the extent and aggressiveness of prostate cancer if initial diagnosis is suspected.

Tchniques of prostate biopsy

Prostate biopsies can be classified based on the technique and guidance method used to obtain tissue samples. The most common types are:

1. Transrectal Ultrasound (TRUS)-Guided Biopsy

• Description: A thin ultrasound probe is inserted into the rectum to visualize the prostate. A spring-loaded needle then takes tissue samples through the rectal wall.
• Advantages:
  • Minimally invasive.
  • Performed under local anesthesia.
  • Quick and widely available.
• Disadvantages:
  • Slightly higher risk of infection due to rectal access.

2. Transperineal Biopsy

• Description: Tissue is collected by inserting a needle through the skin of the perineum (the area between the anus and scrotum). Usually guided by ultrasound or MRI.
• Advantages:
  • Reduced infection risk compared to the transrectal approach.
  • Better access to the anterior and apex of the prostate.
• Disadvantages:
  • May require general or spinal anesthesia.
  • Slightly more invasive.

3. MRI-Guided Biopsy

• Description: Uses real-time MRI imaging to precisely target suspicious areas of the prostate. Tissue samples can be obtained transrectally or transperineally.
• Advantages:
  • High accuracy in detecting clinically significant cancer.
  • Targets specific areas rather than sampling blindly.
• Disadvantages:
  • Longer procedure time.
  • More expensive and less widely available.

4. Fusion Biopsy

• Description: Combines MRI imaging with real-time ultrasound guidance. MRI data helps to identify suspicious areas, which are then targeted during ultrasound-guided biopsy.
• Advantages:
  • Combines the precision of MRI with the convenience of ultrasound.
  • Highly effective for detecting significant cancer.
• Disadvantages:
  • Requires specialized equipment and expertise.

5. Saturation Biopsy

• Description: An extended biopsy technique that collects a higher number of samples (20–40 or more) from multiple zones of the prostate.
• Indications:
  • Used in cases of repeated negative biopsies but persistent suspicion of cancer.
  • Often performed transperineally.
• Disadvantages:
  • More invasive and time-consuming.
  • Greater discomfort post-procedure.

6. Transurethral Biopsy

• Description: Performed using a cystoscope inserted through the urethra, allowing the doctor to take tissue samples directly from the prostate.
• Advantages:
  • Useful in cases where transrectal or transperineal approaches are not feasible.
• Disadvantages:
  • Less commonly used.
  • Requires general or spinal anesthesia.

Choosing the right method depends on patient-specific factors, including risk level, anatomy, and available resources. Consultation with a urologist is essential to determine the most suitable type.

Complications

A prostate biopsy is generally a safe procedure, but like any medical intervention, it carries some risks of complications. These may vary depending on the biopsy technique, patient health, and individual response to the procedure.

Common Complications

Blood in Urine (Hematuria): Temporary blood in the urine is common and usually resolves within a few days to a week.

Blood in Semen (Hematospermia): May persist for several weeks but is generally harmless.

Rectal Bleeding: Mild rectal bleeding may occur, especially after a transrectal biopsy.

Pain or Discomfort: Soreness in the rectal or perineal area is common but usually mild.

Less Common Complications

Infection: Risk of infection, including urinary tract infections (UTIs) or, rarely, sepsis (a serious bloodstream infection). Antibiotics are typically prescribed to minimize this risk.

Urinary Retention: Temporary difficulty urinating due to swelling or bleeding in the prostate.

Fever: A fever after the biopsy may indicate an infection and requires immediate medical attention.

Rare Complications

Severe Bleeding: Uncontrolled or prolonged bleeding, though rare, may require medical intervention.

Tissue or Organ Injury: Accidental injury to nearby tissues, such as the rectum or urethra, is very uncommon.

Allergic Reaction: Rarely, a patient may have an allergic reaction to local anesthesia or antibiotics used during the procedure.

Prevention and Management

• Antibiotics: Prescribed before and after the procedure to reduce infection risk.
• Hydration: Drinking plenty of water can help flush the urinary tract.
• Monitoring: Patients should report persistent symptoms like high fever, severe pain, or prolonged bleeding to their healthcare provider promptly.

Consulting a urologist and following pre- and post-procedure instructions can significantly reduce the risk of complications.

Results of a prostate biopsy

The results of a prostate biopsy provide critical information about the condition of the prostate gland. They are usually available within a few days to a week and are interpreted by a pathologist. Here’s what the results may indicate:

Benign (Non-Cancerous) Findings

• Normal Tissue: No signs of cancer or other abnormalities.
• Prostatitis: Inflammation of the prostate gland.
• Benign Prostatic Hyperplasia (BPH): Non-cancerous enlargement of the prostate.
• Atrophy or Other Non-Malignant Changes: Indicates normal aging or other benign conditions.

Suspicious Findings (Pre-Cancerous Lesions)

• Prostatic Intraepithelial Neoplasia (PIN):
  • Low-Grade PIN: Generally not associated with a higher risk of cancer.
  • High-Grade PIN: May indicate an increased risk of cancer, requiring closer monitoring or further testing.
• Atypical Small Acinar Proliferation (ASAP):
  • A finding that is suspicious for cancer but not definitive; further evaluation may be needed.

Cancerous Findings

• Prostate Cancer Diagnosis:
  • Identified cancer is graded using the Gleason Score, which assesses how aggressive the cancer cells appear under a microscope.

Gleason Score and Grading

The Gleason Score is derived by adding the two most common patterns of cancer cells (graded on a scale of 1–5):

• Gleason Score 6: Low-grade, slow-growing cancer.
• Gleason Score 7: Intermediate-grade cancer.
• Gleason Score 8–10: High-grade, aggressive cancer.

4. Staging and Risk Stratification

If cancer is detected, the biopsy results are used to:

• Determine the extent and aggressiveness of the cancer.
• Guide treatment decisions such as active surveillance, surgery, radiation, or other therapies.

Next Steps Based on Results

• Normal or Benign: Routine monitoring or follow-up if symptoms persist.
• Suspicious or Pre-Cancerous: Additional tests or repeat biopsy may be recommended.
• Cancer Detected: The doctor will discuss staging, treatment options, and prognosis based on the biopsy findings and other diagnostic data.

Always consult a urologist or oncologist for a detailed explanation of your biopsy results and personalized care recommendations.

Summary

A prostate biopsy is a diagnostic procedure used to detect prostate cancer or other abnormalities. It involves collecting small tissue samples from the prostate, typically guided by ultrasound or MRI, and analyzing them under a microscope. The procedure is recommended when PSA levels are elevated, a digital rectal exam reveals abnormalities, or imaging shows suspicious areas.

While generally safe, it may cause temporary side effects like mild bleeding or discomfort. Biopsy results can indicate benign conditions, pre-cancerous changes, or prostate cancer, with findings graded using the Gleason Score to guide treatment decisions.

Prof. Dr. Emin ÖZBEK

Urologist

Istanbul- TURKIYE