Tumor Biopsy

If a tumor is found in the prostate gland, a biopsy is performed to determine the type of cancer, its location, and stage of the prostate cancer.

Before undergoing the prostate biopsy, patients should abstain from alcohol, aspirin, and nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., ibuprofen) for 1 week. Due to potentially severe gastrointestinal and cardiovascular side effects, NSAIDs should only be used as instructed.

They are required to take one Fleet enema the night before the procedure and one 2 hours before the biopsy. An oral antibiotic (usually ciprofloxacin) is prescribed to be taken the day before, the day of, and 2 days after the biopsy.

The biopsy is performed with the patient lying on his side with his knees brought up to his chest. A biopsy needle, similar to one used to draw blood or administer injections, is inserted through the perineum into the tumor. A probe, guided by transrectal ultrasound (TRUS), is inserted into the rectum to help the physician properly place the needle, which is projected through the tip of the probe. A cell sample is extracted from one or several areas of the tumor into the syringe. The sample(s) is analyzed by a pathologist to confirm the diagnosis of a cancerous tumor and determine its type. The results are obtained within 5–10 working days.

Gleason score

The biopsy sample(s) is examined under a microscope for cells or groups of cells that are markedly different from healthy tissue. The greater the disparity between the healthy cells and those that are malignant, the more likely the tumor is aggressive and will spread (metastasize).

The pathologist examines two tissue samples taken from different areas of the tumor and assigns a score of 1 to 5 to each sample. The more abnormal the tissue, the higher the score. The sum of the two produces the Gleason score. Gleason scores of 2 to 4 indicate that the cells are well differentiated, meaning the tissue is not too abnormal; 5 to 7 moderately differentiated; 8 to 10 poorly differentiated. Higher scores suggest aggressive tumors that likely require aggressive treatment.

Prostate Biopsy Complications

After a biopsy, blood in the urine (hematuria) and stool is common and usually diminishes within 1–2 weeks. Patients also experience a dull ache in the perineum for several days. Men are advised to refrain from sexual intercourse for 3–5 days. Blood may appear in the semen.

If the patient develops a large number of blood clots or cannot urinate, the physician should be contacted or the patient should go to the emergency room.

Rarely, biopsy of a cancerous tumor also may cause spreading, or "seeding," of cancer cells along the path of the biopsy needle.

Computed tomography (CT scan)

Computer-assisted tomography (CAT scan or CT scan) is an x-ray procedure that produces three-dimensional images of internal organs and glands. It can be used to detect pelvic lymph nodes enlarged by cancer, but results may be insufficient for diagnosis. CT scans are used only when tumors are large or PSA levels are high.

Bone scan

A bone scan is a nuclear imaging procedure that is used to detect metastasis to bones. It is not used in patients with small cancers and low PSA levels.

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 09 Jun 1998

Last Modified: 01 Oct 2015