Prostate biopsy

The similarity of the echographic pattern of prostate cancer and inflammatory changes in the gland makes it necessary to use a complex of differential-diagnostic measures, the most accurate of which is a polyfocal biopsy of the prostate under ultrasound control followed by a morphological study of the tissues obtained.

In addition, despite the abundance of methods for diagnosing prostate cancer, mandatory morphological confirmation of the disease is necessary. There are two methods for conducting a biopsy of the prostate - transrectal or transperineal. The transperineal biopsy has a number of disadvantages that significantly limit its use: trauma atishchyu manipulation, the need for local or general anesthesia, a relatively high incidence of complications, the lack of dynamic ultrasound during the biopsy needle. In this connection, a transrectal multifocal biopsy can now be considered a method of selecting the morphological diagnosis of prostate cancer.

[1], [2], [3], [4], [5], [6]

Indications for prostate biopsy

The following indications for the primary biopsy are distinguished:

• total serum PSA level> 2.5 ng / ml (or above the corresponding age norms);
• suspected prostate cancer with digital rectal examination;
• Suspicion of prostate cancer with transrectal ultrasound.

Indications for repeated biopsy (in the absence of prostate cancer in primary biopsy):

• growth of PSA after primary biopsy;
• PSA free / PSA total <15%;
• PSA density> 20% (ratio of total PSA to prostate gland volume according to TRUSD);
• prostatic intraepithelial neoplasia (IDU) of high degree (three months after the initial biopsy);
• suspicion of local tumor recurrence after radical prostatectomy according to PRI and TRUS.

How is prostate biopsy performed?

A prostate biopsy is performed on an outpatient basis. Preparation for a biopsy consists in cleaning the intestines on the eve of manipulation and preventive administration (per day) inside the antibiotics (the cup of fluoroquinolones) and metronidazole. After a biopsy, it is possible to continue the prophylactic intake of antibiotics for 5 days. The procedure is carried out both in the patient's position on the side and in the position for the crotch operations. Biopsy of the prostate gland requires anesthesia. The best results are achieved with the introduction of local anesthetics around the prostate: this is a fairly reliable, safe and convenient method. 20 of 23 studies showed its advantage over placebo or rectal administration of a gel with a local anesthetic. Anesthesia is performed by administering a 1% solution of lidocaine in a dose of 20 ml to paraprostatic fiber on both sides. The number of injections is determined by the urologist. It is generally accepted to supplement the biopsy with targeted tissue taking from suspicious hypoechoic foci.

For biopsy, special modern devices are used, which make it possible to obtain a sufficient amount of tissue for histological examination. If the biopsy specimen is correctly prepared, the length of each biopsy specimen should be at least 15 mm and the diameter 1 mm.

Among the complications of biopsy, the most common are: pain in the rectal region (up to 35% of cases), hematuria (15-35%), acute prostatitis (5-10%), acute urinary retention (2%), rectal bleeding (296 ). Usually complications do not require inpatient care, but in case of hospitalization, symptomatic therapy is recommended.

Contraindications to biopsy of the prostate

There are the following contraindications for the biopsy of the prostate:

• acute prostatitis;
• complicated hemorrhoids;
• acute inflammatory diseases of the rectum and anal canal;
• severe stricture of the anal canal;
• state after abdominal perineal rectal extirpation;
• diseases that lead to severe disorders of the blood coagulation system (hypocoagulation).

In addition, puncture biopsy of the prostate gland is a method of differential diagnosis of chronic prostatitis, prostate cancer, benign hyperplasia and tuberculosis. Sometimes, under the guise of chronic inflammation, prostate cancer develops. It is for this reason that it is advisable to determine the level of the prostatic specific antigen (PSA) and prostate biopsy (in the case of a PSA increase above 2.5 ng / ml).

[7], [8]