What is the prostate? It is a gland the size of a walnut, located in the male urinary tract. It is situated below the bladder and surrounds the urethra at the bladder outlet (figure 1). The function of the prostate is to produce nutrients for sperm.

What is the prostate?

It is a gland the size of a walnut, located in the male urinary tract. It is situated below the bladder and surrounds the urethra at the bladder outlet (figure 1). The function of the prostate is to produce nutrients for sperm. The prostate gradually begins to increase in volume in middle age (benign enlargement).

What is a biopsy?

It is a procedure in which a needle is inserted into the prostate to remove small fragments for diagnostic examination.

Why is a biopsy performed?

Prostate enlargement may be asymptomatic or eventually interfere with the quality of urination. Symptoms such as decreased urinary stream, frequent urination, or getting up at night to urinate may be signs or symptoms resulting from prostate enlargement. It can be said that "benign" enlargement (benign prostatic hyperplasia) is normal, and biopsies are not necessary.

However, the presence of a nodule (a hardened area in the gland) does not cause any symptoms and can only be detected on physical examination: the digital rectal exam.

Another indication for prostate biopsy would be an above-normal elevation of PSA (prostate-specific antigen) in the blood. PSA is produced by both normal and cancerous prostate tissue. In the latter case, there is greater leakage of PSA into the blood.

Today, if there is suspicion of prostate cancer based on PSA or physical examination, a 3 Tesla magnetic resonance imaging (MRI) is performed. This imaging exam can show areas of the gland that may have adenocarcinoma. They are classified as PIRADS (Prostate Imaging Reporting and Data System) from 1 to 5. PIRADS 1 and 2 probably do not have a clinically significant tumor. PIRADS 3 already has about a 23% chance of having a tumor, and lesions 4 and 5 are highly suspicious for tumor.

How is the biopsy performed?

Today, the standard biopsy is performed with ultrasound assistance, using fusion of MRI images with ultrasound images. In this way, it is possible to sample exactly the suspicious area that appears on the MRI performed before the biopsy. The ultrasound probe is placed in the rectum, the prostate is visualized, and the images are synchronized with the MRI images previously loaded into the device. Today, transrectal ultrasound is performed, but the biopsy needle is accessed through the perineum. This approach allows access to regions below and above the urethra, which is very difficult in transrectal biopsy, in addition to greatly reducing the possibility of infection. Initially, the suspicious area is sampled, and then a "mapping" or randomized sampling of the prostate is performed using images and positioning allowed by the ultrasound.

In each study, 12 sampling fragments are removed and 2 to 4 from the suspicious areas on the MRI.

Preparation for biopsy

1. The use of aspirin and/or anticoagulants (including Ginkgo biloba) can cause bleeding after the biopsy. Their use should be discussed before the procedure.

2. To further reduce the risk of infection, prophylactic antibiotics should be used.

3. Most procedures are performed with sedation (brief anesthesia).

After the biopsy

The patient is discharged from the hospital/laboratory as soon as they have a spontaneous urination and, if the exam was performed with sedation, after being fully awake. Generally, there is some minor local discomfort (in the perineum) after the exam. Blood may be present in the urine and mixed with stool for a few days, which is normal. Semen may also come mixed with blood for a somewhat longer period (up to 1 month). Strenuous physical activities and sexual intercourse should be avoided for 24 hours. The pathological study (analysis of the removed tissues) is usually ready in 3 to 5 days, when a follow-up appointment should be scheduled.