Modern aspects of prostate biopsy

An important point in the diagnosis of tumor formations of any location is a morphological study. Only histological verification of the diagnosis provides grounds for the use of radical surgery, radiation therapy, or drug treatment. The purpose of a pancreatic biopsy is not to state the fact of the disease, but to highlight the stage of the process and the choice and tactics of treating the disease.

History of the development of prostate biopsy
For suspected prostate cancer, back in 1930, Ferguson began to use fine-needle aspiration biopsy, which was later used relatively often in the 60-70s (Esposti P.L. , 1971). Previously, transurethral resection was also used for prostate biopsy (Barnes et al., 1947), excision of a section of the prostate gland through the rectum (Lazarus, 1946; Poutasse, 1953; Culp, 1954); Attempts were made to detect prostate cancer by special staining of urine sediment (Bouer, 1950).

Prostate biopsy as we know it has become most widely used in clinical practice over the past 10-15 years, when high-speed automatic biopsy devices consisting of a biopsy gun (BIP, Bard, PRO-MAG, etc.) became available. and disposable biopsy needles 16 or 18 gauge (Fig. 1).

Prostate biopsy is an invasive procedure, so the risk of complications should not outweigh the benefits of diagnosis and treatment.

Indications for repeat biopsy
(if there is no prostate cancer on the initial biopsy)

• persistent high level of blood PSA (or its increase in dynamics) after the initial biopsy
• PSA free/PSA total < 15%
• PSA density (ratio of total PSA level to prostate volume according to transrectal ultrasound) more than 20%
• high-grade prostatic intraepithelial neoplasia (1 month after initial biopsy)
• suspicion of local tumor recurrence after radical prostatectomy according to digital rectal examination and transrectal ultrasound

Biopsy should be performed 3-6 months after the initial examination

DYNAMIC TRANSRECTAL BIOPSY OF THE PROSTATE

Dynamic transrectal biopsy of the prostate gland is necessary if the development of secondary hormone resistance is suspected during hormonal therapy.

It is advisable to perform a biopsy 6 months after organ-sparing treatment (radiation therapy, brachytherapy, radiofrequency, cryoablation) to assess the adequacy of tumor pathomorphosis.

Also, dynamic transrectal biopsy of the prostate gland is performed after a long remission of the disease (in such cases, the tumor develops from a new pool of cells, which means that it has different characteristics than the primary tumor and, accordingly, requires other treatment methods).

Accesses for prostate biopsy.
The following accesses can be used for prostate biopsy:

• transrectal
• transperineal
• transurethral
• transvesical
• transgluteal
• open intraoperative prostate biopsy

Less commonly used is perineal biopsy, which is recommended for anal stenosis or in the case of rectal resection or amputation, when it is impossible to insert an ultrasound probe or finger into it. Another extremely rarely used technique in the same category of patients is transgluteal biopsy of the prostate gland under the control of a computed tomograph (Knight M. et al., 2000).

We perform prostate biopsy under transrectal ultrasound control (Fig. 6).

Ultrasound guidance of biopsy provides

• correct and precise guidance
• spatial orientation (Fig. 7)

Fig.6. Transrectal puncture biopsy of the prostate under ultrasound guidance (according to A.V. Karman, 2006).

Fig.7. The moment of sampling material from the left lobe of the prostate gland. The arrow marks the puncture needle.

To perform a prostate biopsy you need:

• ultrasound scanner equipped with a rectal probe and biopsy program
• guide attachment compatible with this type of rectal sensor
• automatic biopsy gun
• disposable biopsy needles
• an experienced urologist who knows the basics of ultrasound
• availability of a properly equipped pathological laboratory for high-quality processing of the collected material

Transrectal puncture trephine biopsy of the prostate

Material and technical support of the method:
Ultrasound scanner (Fig. 8), equipped with a rectal sensor with the ability to scan in a frequency mode of 7.5 MHz, having an instrumental channel for carrying out a special biopsy cutting needles with a diameter of 1.8 mm (16G).

Fig.8. Ultrasound scanner

Patient preparation:

• general blood test, urine test, coagulogram, ECG
• preliminary examination of the urologist performing the procedure
• 7 days before the biopsy, stop taking medications that affect blood clotting
• 3 days before the biopsy, stop taking NSAIDs
• antibacterial therapy – within 4 days before manipulation (fluoroquinolones)
• cleansing enema (the day before)
• informed consent of the patient for the procedure

As is known, the prostate gland consists of several anatomical sections (Fig. 9):

Fig.9. Zonal anatomy of the prostate gland (according to J. E. McNeal, 1981).

• peripheral zone where prostate cancer is most often localized
• central zone
• transition zone
• fibrovascular stroma

Despite the fact that 75% of cancer is detected in the peripheral zone of the prostate gland, according to our data, 10% of patients have cancer diagnosed in the transition zone. In this connection, we consider it obligatory to collect prostate tissue from the transition zone (Fig. 10).

Fig. 10. Schematic illustration of the transrectal prostate biopsy technique.

Biopsy of the pancreas is performed under intravenous atheralgesia. As a rule, there are special requirements for the length of the tissue column; it should not be less than 15 mm, otherwise tissue is re-sampled from this area of the prostate.

Possible complications of prostate biopsy.

According to our own and literary data, after a prostate biopsy the following are possible:

• short-term rectorrhagia – 12%
• moderate hematuria – 25%
• hemospermia – 18%
• acute prostatitis (or exacerbation of chronic) – 8%
• acute urinary retention – 0.5%
• hypotension during biopsy – 2%
• acute orchiepididymitis – 0.2%

RESULTS OF OWN RESEARCH.

Fig. 11. Diseases identified based on the results of prostate biopsy.

1812 prostate biopsies were performed during the period 2008-2014. The diagnoses established based on the biopsy results are shown in Fig. 11.

The distribution of patients with different stages of prostate cancer by age groups is presented in table. 1

Table 1.
Distribution of patients by age groups depending on the stage of prostate cancer

The data obtained allowed us to draw the following conclusions.

1. The general nosological structure of the performed biopsies is dominated (60%) by adenomatous prostatic hyperplasia with or without chronic prostatitis.
2. The primary detection of prostate cancer was 39% (of the total number of procedures performed), which is comparable to the results of foreign studies.
3. In the group of patients with diagnosed prostate cancer, only 41% (287) of patients were in the “choice” group for radical prostatectomy (stage T1-2, Gleason score less than 7, age under 74 years).
4. There was a high rate of primary detection of malignant prostate tumors in the late stages of the disease (48% – 336 patients).

Fig.1. Biopsy gun and disposable biopsy needle

The first transrectal prostate biopsy under the control of transrectal ultrasonography was performed in 1988. Subsequently (in the late 80s) K.K.Hodge et al. the method of prostate biopsy from 6 points (the so-called “sextant” biopsy), which later became generally accepted, was substantiated and proposed, in which samples of prostate tissue are taken along the parasagittal line between the median sulcus and the lateral border of the prostate from the base, middle part and apex of the right and left shares (Fig. 2).

Fig.2. Scheme of sextant biopsy of the prostate (according to Pushkar D.Yu., 2003).

The sextant (6-point) biopsy proposed by Hodge was performed until 1991. Studies have shown that false-negative results of biopsy performed using this technique were obtained in 10-35% of patients (Chappell B., 2005, Singh H., 2004). In 1995, T.A. Stamey and co-authors proposed modifying this technique by lateralizing the material taken and increasing the number of tissue sections (Fig. 3).

Fig.3. Modification of sextant biopsy of the prostate (according to Pushkar D.Yu., 2003).

In 1997, L.A. Eskew proposed an advanced biopsy technique (Figure 4).
Figure 4. Variants of prostate biopsy schemes.

When performing prostate biopsy, we adhere to the technique proposed by Presti (Fig. 4.) 8-point for prostate volume up to 40 cm3). With an increase in prostate volume, an additional tissue section is added for every 5 ml, but not more than 12 sections.
These innovations made it possible to increase the detection of prostate cancer by 24-38% (Chang J.J., Shinohara K., 1998, Gore J.L., Shariat S.F., 2001). Currently, the search for the optimal scheme for taking biopsy material continues (Fig. 4).

INDICATIONS FOR PROSTATE BIOPSY

• total serum PSA level more than 4.0 ng/ml (or above the corresponding age norms)
• increase in blood PSA value over a year by more than 0.35 ng/ml
• suspicion of prostate cancer on digital rectal examination
• suspicion of prostate cancer during transrectal ultrasound examination

As a rule, prostate cancer is localized in the peripheral zone (75% of cases) and during ultrasonography is visualized as a node with unclear contours and reduced echogenicity (Fig. 5), but in some cases the tumor node can be isoechoic and hyperechoic. p>

Fig.5. Hypoechoic node in the peripheral zone of the right lobe of the prostate gland.

CONTRAINDICATIONS FOR PROSTATE BIOPSY.

Absolute:

• serious condition of the patient due to concomitant pathology
• mental disorders accompanied by inappropriate behavior of the patient
• acute inflammatory processes of the rectum and prostate
• complicated hemorrhoids
• severe anal stricture
• condition after abdominoperineal extirpation of the rectum

Relative:

• taking anticoagulants on the eve of the intervention (diseases leading to disorders of the blood coagulation system)
• increased blood pressure more than 140/80 mmHg
• patient age over 80 years with no clinical symptoms