Transrectal Ultrasound Guided Prostate Biopsy

Figure 28.1
Operating table with biopsy tools including sterile sheet and gloves, numbered test tubes with Formalin, 22G with anesthetic solution, a biopsy needle, not reusable spring-action device. In the corner two details: (a) the bayonet-shaped needle tip and (b) the spring-mechanism

Enema and Antibiotic Prophylaxis

During the last decade a 4.3 % risk of hospital admission for PBx-related infection was computed [19]. Recently, a Cochrane review concluded that enema and antibiotics together reduce the risk of bacteremia compared to antibiotics alone [13]. On the other hand, self-administered enema on the same day of the examination can facilitate US visualization by evacuating gas and fecal matter that cause interference with ultrasound.

Uncomfortable mechanical bowel preparation such like those generally used for colonoscopy, does not reduce the risk of complications despite the rectal enema [7]. Then, disinfecting the needle tip by a safe amount of formalin (10 %) after each biopsy core has been suggested in a large study as simple technique to reduce the risk of urinary infection and sepsis [15].

Regarding antibiotic use, several classes of antibiotic are effective for prophylaxis however quinolone are the drugs of choice [21]. Although no wide consensus exists on the prophylaxis duration, a 3–7 days course is generally adopted among urologists [2]. Particular attention should be take regard the local rate of quinolone-resistant organism due to increasing rate of those infections. In this concern, some researchers have suggested to use rectal swab cultures to guide antibiotic choice. Finally, the prophylaxis for patients at increased risk of endocarditis should include coverage for both gram positive and gram-negative bacilli.

Stop Anticoagulation Therapy

Usually, any anticoagulation medications are stopped or replaced with low molecular weight heparin for an sufficient length before biopsy. However, some comparative studies showed no significative difference in term of bleeding rate when aspirin intake is not stopped at the time of the biopsy [14, 16] although it prolongs the duration of self-limiting hematuria [12] and the risk of bleeding looks to be correlated to the core number [5].

Patient Consent

Due to its invasive nature the risk of rectal bleeding, hematuria, urinary retention and hematospermia should be discussed in detail as well as a written consent should be obtained.


Reducing Patient Pain

The administration of anesthetic medications to reduce patient discomfort related to PBx has been largely showed by an high number of published studies. Therefore, the absence of anesthesia may be considered malpractice since the most common guidelines also recommend to perform anesthesia [1, 9]. An intrarectal local anesthesia with lidocaine (2 %) gel has been proposed as simple way to achieve pain reduction. However, the periprostatic nerve block ensures an higher and durable pain relief as showed in randomized studies. About the technique, 10-ml lidocaine – showed to be the best amount of anesthetic – are injected through a 22 gauge needle while the site of injection may be different [18] for instance, around the prostate vascular pedicle – as originally reported by Nash et al. [17] – at three location (apex, mild, basis) and at pelvic plexus [4]. It is reasonable that combining the use intrarectal gel and periprostatic block may offer the maximum comfort. The first one may reduce the patient discomfort due to ultrasound probe in the anus while the periprostatic block may prevent the pain from puncture of prostate capsule and parenchyma.

Patient Position

Patient is collocated in left lateral decubitus with his buttocks places near the bed edge. In order to create a wide working area to easily move the ultrasound probe, the patient legs are bent like fetal position, and the pelvis lightly tilted front.


The last few years have showed that a sextant biopsy scheme (six core) was inferior to an extended scheme (10–12 core) in term of prostate cancer detection rate. Certainly, the direction and core number determine the procedure’s sensitivity. For these reasons, the sample sites should be bilateral from apex to base as far posterior and lateral as possible in the peripheral gland. Sampling the lateral prostatic horn increases about a 25 % the ability to detect prostate cancer as well as the apex and the base of the peripheral gland are the sites at which prostate cancer is most likely to be located while the para-sagittal biopsies have been demonstrated to have the lowest probability of PCa at initial biopsy. Likewise, the use of a extended scheme has been showed to increase the risk of Gleason Score concordance between prostate biopsy and radical prostatectomy specimen [18].

Keeping in mind that the 12 core is a concern in large prostate (more than 40 cc), such sampling can be considered adequate as well as a good compromise with compliance in case of initial biopsy. At the same time, the necessity of biopsying single hypoechoic lesions seems to be no longer necessary because the low accuracy of that finding as well as there is little benefit to adding transitional zone biopsy.

However, the initial prostate biopsy does not rule out the cancer diagnosis with certainty requiring often a repeat biopsy. Although there is not clear consensus on when to perform the rebiopsy, the saturation biopsy technique (>20 core) is considered as an correct choice with a cancer detection rate ranged from 17 to 41 %. To note, the probability of a positive biopsy generally decreases in according to the number of previous biopsies: men with total serum PSA level of 4–10 ng/ml undergone to one, two, three, and four previous biopsies have a risk of cancer diagnosis of 22 %, 10 %, 5 %, and 4 %, respectively [8]. Again, the new sampling should be accurately directed to the apices, to anterior prostate and very lateral edges including also transitional zone whereas this one has low detection rate (Fig. 28.2). Recently, multiparametric magnetic resonance image-targeted biopsy has been introduced as further way to detect tumor in case of persistent clinical suspicious of cancer.


Figure 28.2
A scheme to elucidate the concern to guide the prostate sampling laterally and accurately to apex. Although a risk of missing prostate gland increases, it has been showed that lateral biopsies increase detection rate, likely due a greater glandular presence than paramedian area (P peripheral zone, TR transitional zone)

Usually a preliminary trans rectal ultrasound is performed in order to compute prostate volume. Then, local anesthesia is performed. Finally, the biopsy-needle is advanced through the biopsy guide and two resistances can be generally felt. The first one is the rectal wall while the second one is the prostatic capsule. Paying attention on ultrasound images, a slight distortion of capsular profile can be noted as well as the needle tip. A this point the sampling can be achieved. To note, the needle tip must to be at target point before biopsying as well as the probe should be not moved when the needle is at that point in order to avoid rectal bleeding. Furthermore, when biopsies are performed at base or anterior prostate, the risk of penetrating into bladder exists due to needle advancement. This may explain protract hematuria at the end of procedure. In such circumstance, inserting a urinary catheter should be considered.

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Nov 21, 2017 | Posted by in UROLOGY | Comments Off on Transrectal Ultrasound Guided Prostate Biopsy
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