My Expat Diary - Russia (Krasnoyarsk, Trans-Siberian Express) 08/28/2017
Transrectal ultrasound TRUS was first developed in the s. TRUS-guided biopsy, under local anaesthetic and prophylactic antibiotics, is now the most widely accepted method to diagnose prostate cancer. However, the sensitivity and specificity of greyscale TRUS in the detection of prostate cancer is low.
Prostate cancer most commonly appears as a hypoechoic focal lesion in the peripheral zone on TRUS but the appearances are variable with considerable overlap with benign lesions.
Because of the low accuracy of greyscale TRUS, TRUS-guided TRUS Prostata Krasnoyarsk have become established in the acquisition of systematic biopsies from standard locations. The number of systematic biopsies has increased over the years, with 10—12 cores currently accepted as the minimum standard. This article describes the technique TRUS Prostata Krasnoyarsk TRUS and biopsy and its complications. Novel modalities including contrast-enhanced modes and elastography as well as fusion techniques for increasing the sensitivity of TRUS-guided prostate-targeted biopsies are discussed along with their role in the diagnosis and management of prostate cancer.
Over 35 new cases of prostate cancer are diagnosed per annum in the UK and there are over 10 TRUS Prostata Krasnoyarsk annually [ 1 - 4 ]. The lifetime risk of being diagnosed with prostate cancer is one in nine. Over the last 20—30 years the incidence of prostate cancer has quadrupled, largely because of the introduction of widespread prostatic-specific antigen PSA testing, although the incidence in the UK may now have reached a plateau UK Prostate Cancer Statistics, [ 7 ].
In the USA, the incidence peaked inand death rates have been decreasing TRUS Prostata Krasnoyarsk [ 8 ]. In the UK there has been TRUS Prostata Krasnoyarsk significant decline in the age-standardised mortality rate between andbut the overall mortality rates have remained largely unchanged, as the decreasing mortality rate is counteracted by the aging population.
Risk factors for prostate cancer include age, a positive family history, abnormal digital rectal examination DREraised PSA level and ethnicity. Black African and Caribbean men have two to three times the risk of being diagnosed with and dying of prostate cancer than white men, whereas Asian men have the lowest risk. Prostate cancer can be divided into low- intermediate- and high-risk disease, depending on the aggressiveness of the tumour.
Since the s there has been a marked change in the presentation TRUS Prostata Krasnoyarsk prostate cancer. Before PSA testing and transrectal ultrasound TRUS Prostata Krasnoyarsk became widely available, most patients presented with cancer-specific symptoms owing to locally advanced disease and the cancers were diagnosed by DRE, so that the majority were diagnosed at stage T2 Table 1 or more.
Over the past 20 years the proportion of males with low- vs high-risk disease at diagnosis has shifted significantly from It is also unable to distinguish between aggressive and indolent cancers.
PSA is a kallikrein-like serine protease secreted by epithelial cells in the prostate gland and measured in the blood. Therefore, PSA is organ- but not cancer-specific. Levels outside this range denote a raised risk of cancer, the risk rising with the level of PSA.
Currently there is no formal national screening policy for prostate cancer, although opportunistic screening in primary care does occur in males presenting with lower urinary tract symptoms.
Two recent reviews of several randomised controlled trials concluded that there was insufficient evidence to support the use of PSA testing to screen for prostate TRUS Prostata Krasnoyarsk and its use may potentially cause harm [ 1011 ]. Screening for prostate cancer does not have a significant impact on either overall mortality or death from prostate cancer. Screening helps to diagnose prostate cancer at an earlier stage but the benefit-to-risk ratio remains uncertain because of significant morbidity associated with treatment.
TRUS was pioneered in the early s [ 12 ]. Modern transducers typically are end-firing probes scanning at frequencies of 5—10 MHz. TRUS Prostata Krasnoyarsk prostate is divided into TRUS Prostata Krasnoyarsk anatomical zones Figure 1 and these can TRUS Prostata Krasnoyarsk depicted by TRUS [ 1314 ] Figure 2.
The CZ is difficult to distinguish from the TZ in a healthy adult. Within the central gland, the ejaculatory ducts can be visualised as echogenic tramlines on longitudinal scans. TRUS Prostata Krasnoyarsk can be traced posteriorly to the ampulla of vas, where the seminal vesicles join.
Between the seminal vesicles the vas deferens can be seen arising from the ampulla of vas. The bladder neck fuses with the prostate and external TRUS Prostata Krasnoyarsk sphincter distal to the prostatic apex can be seen as slightly echopoor structures owing to anisotropy from orientation of smooth muscle fibres relative to the prostate. The prostate does not have a true capsule, but a TRUS Prostata Krasnoyarsk boundary can be seen around the prostate—fat interface and this has been termed the prostatic capsule.
It is normally smooth and regular. The neurovascular bundles can be identified posterolateral to the prostate in the fat-filled echogenic triangular-shaped space between the seminal vesicles and the prostate. This is of relevance to the sonologist as this is the site where local anaesthesia may be introduced and also is a site of potential capsular weakness prone to local tumour spread.
The levator ani muscles are seen as linear structures lateral to the prostatic bed. Anatomy of the prostate gland and surrounding structures. Reproduced with permission from [ 14 ]. Axial transrectal ultrasound a—c and longitudinal images of the normal prostate d. Inspection of the gland should focus on identifying asymmetry, areas of increased vascularity, hypoechogenicity and the presence of focal bulges, irregularity or breaches TRUS Prostata Krasnoyarsk the capsule.
These features are associated with the presence of cancer and should be documented, but are not sufficiently reliable to make a diagnosis without obtaining TRUS Prostata Krasnoyarsk biopsy.
Current indications for prostate biopsy are given in Table 3. Absolute contraindications to TRUS biopsy include surgical absence of rectum, TRUS Prostata Krasnoyarsk pouch, inflammatory bowel disease especially Crohn's disease and severe bleeding diatheses. Relative contraindications to biopsy are acute prostatitis, perianal inflammation and severe haemorrhoids.
Written consent should be obtained. The patient's bladder should ideally be empty before the procedure. Prophylactic antibiotics should TRUS Prostata Krasnoyarsk administered according to local protocol TRUS Prostata Krasnoyarsk below. The patient is then positioned in the left lateral decubitus or lithotomy position, an endorectal probe with the biopsy guide is inserted and local anaesthetic administered around the prostate.
The application of local anaesthetic is now standard practice [ 15 - 17 ]. The anaesthetic may be administered around the neurovascular bundle between the base of the gland and the seminal vesicles Figure 4adjacent to the apex or into Denonvilliers' fascia. None of the sites has been shown TRUS Prostata Krasnoyarsk be superior but it is the authors' practice to inject 2.
It should be noted that injecting directly into the gland is of no benefit. Potential complications of local anaesthesia use include pain caused by needle puncture, systematic lidocaine toxicity, temporary urinary incontinence because of anaesthesia of the external urethral sphincterartefact formation on the TRUS image from air introduced during TRUS Prostata Krasnoyarskperiprostatic infection and erectile dysfunction [ 19 ].
TRUS Prostata Krasnoyarsk incidence of all these is very low and other studies have found no significant complication rates with the use of local anaesthesia [ 2021 ]. The various TRUS Prostata Krasnoyarsk for anaesthetising the prostate gland.
In 1 the needle is positioned just outside the apex and the local anaesthetic is injected to create a pool around it. In 2 the injection has been made into Denonvilliers' fascia, just beyond the rectal wall. In 3 the local anaesthetic has been introduced around the neurovascular bundle, between the base of the gland and the seminal vesicle.
Any of these sites can be used, as none is of proven superiority, but both sides should be injected for maximal effect. Antibiotic prophylaxis is standard because of the potential for infection, with Escherichia coliTRUS Prostata Krasnoyarsk and Gram-positive organisms being the most commonly identified [ 22 ]. Lee et al [ 24 ] found that the quinolones predominantly ciprofloxacin are the most commonly used prophylactic antibiotics.
Current guidelines recommend TRUS Prostata Krasnoyarsk minimum of one oral antibiotic, such as a quinolone [ 25 ]. This is best commenced a few hours before the TRUS Prostata Krasnoyarsk on the day of the procedure and may be continued for 3—5 days afterwards [ 26 ]. Shorter courses of quinolones, with intravenous gentamicin at the time of the biopsy, may also be used.
Additional prophylaxis is required in patients at risk of endocarditis. Worryingly, a rise in antibiotic-resistant organisms has been recently reported in patients after TRUS biopsy [ 27 ]; therefore, infection rates and local patterns of resistance should be regularly audited. The overall complication rate of TRUS-guided TRUS Prostata Krasnoyarsk biopsy remains low.
Increasing the number of biopsies has been associated with an increase in urinary retention and epididymitis. Urinary retention is thought to be due to prostatic oedema and may occur in the absence of haematuria. Percentage given per biopsy session, irrespective of TRUS Prostata Krasnoyarsk of cores. Adapted from National Comprehensive Cancer Network.
Clinical practice guidelines in oncology. Prostate cancer early detection, v. The incidence of haemorrhage TRUS Prostata Krasnoyarsk with the number of biopsies. Severe haemorrhage requiring hospitalisation is rare: it is almost always per rectum from a rectal vein or artery, and may TRUS Prostata Krasnoyarsk some hours after biopsy. Hospitalisation and transfusion are often necessary, and urgent proctoscopy to cauterise any bleeding points is indicated for suspected arterial bleeds.
Direct compression of the rectal mucosa with the TRUS probe or a rectal balloon may help as a temporary TRUS Prostata Krasnoyarsk. Aspirin and non-steroidal anti-inflammatory drugs have not been conclusively shown to increase the frequency or severity of haemorrhagic complications [ 29 ]. Similarly, clopidogrel must also be stopped for 7 days prior to biopsy.
Anticoagulants are restarted 24 h after biopsy. Haematuria is the commonest form of haemorrhage, but haemospermia can last longest. The number of biopsies has increased since the original sextant biopsy developed by Hodge et al [ 30 ].
The increasing number of biopsies reflects the isoechoic nature of the occult, small, multifocal cancers commonly encountered in modern practice. Thus, sampling is systematic and not random with the biopsies sampling the TRUS Prostata Krasnoyarsk, as TRUS Prostata Krasnoyarsk is the most likely site of cancer. However, there is still wide variation in the number of cores taken, direction of needle and area targeted.
This is reflected in large variations in cancer detection between TRUS Prostata Krasnoyarsk and also in the fact that increasing the number of cores will increase both cancer detection and complication rates [ 32 ]. It TRUS Prostata Krasnoyarsk also be noted that the current systematic biopsy TRUS Prostata Krasnoyarsk do not sample the inner gland because of its lower cancer rate and lower metastatic potential.
Principles behind prostate biopsy. The next three schemes illustrate the octant, core and core regimes, respectively. In current practice the or core regime is favoured. Note how the trajectories are aimed anterolaterally to maximise peripheral zone sampling. Prostate biopsy is used to confirm the clinical diagnosis of TRUS Prostata Krasnoyarsk and stratify tumour aggressiveness. A five-point scale is used to categorise the cellular architecture within a biopsy core from very TRUS Prostata Krasnoyarsk differentiated to undifferentiated.
Because of the multifocal nature of prostate cancer, and the heterogeneity of the cellular architecture, the Gleason score or sum is derived by adding together the two most common Gleason grades across the cores. The combined score ranges from 2 to