Optimising prostate biopsyBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.d8201 (Published 09 January 2012) Cite this as: BMJ 2012;344:d8201
- 1Department of Urology, New York University School of Medicine, New York University, New York, NY 10016, USA
- 2Department of Urology, Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
In the linked study (doi:10.1136/bmj.d7894), Rosario and colleagues assess the effects of transrectal ultrasound guided prostate biopsy in primary and secondary healthcare on patient reported outcomes.1
Transrectal ultrasound guided prostate biopsy is the core means but also the core problem of diagnosing prostate cancer. New and old serum markers, such as prostate specific antigen and its isoforms p2PSA and benign prostatic hyperplasia associated PSA,2 and improved imaging techniques based on fusion of images guided by transrectal ultrasound and magnetic resonance imaging, will certainly optimise patient selection, thus improving specificity (by reducing the number of men undergoing unnecessary biopsy procedures). However, the entire process is handicapped by an ailing biopsy procedure, which has changed little since the introduction of Stamey’s sextant biopsy technique.
Most of today’s research aims to identify new and better serum markers for prostate cancer.3 The main concern is that most of these studies rely on the biopsy procedure and its outcome to judge the statistical performance of the test. The biopsy procedure itself is not standardised across the study participants. The number of cores taken, the direction of the biopsy needle, the area targeted, and three dimensional placement of the needles may vary greatly from case to case as well as between surgeons. Thus, the outcome of these studies is more closely related to the technical performance of the biopsy procedure than to the performance of the marker being investigated. In fact, these studies reported that the sensitivity of the biopsy procedure itself in detecting cancer was 33% at best.4 5 Also, the biopsy procedure still relies primarily on sampling, which is reflected in the fact that increasing the number of cores will increase the cancer detection rate and complications.6
Rosario and colleagues assessed some of these shortcomings while prospectively evaluating the outcomes of prostate biopsy within the ProtecT (Prostate Testing for Cancer and Treatment) study. They found significant differences between centres in the use of local anaesthesia and antibiotic prophylaxis, levels of pain, infective complications, cancer detection, and attitudes towards repeat biopsies, suggesting that changes to practice could greatly improve outcomes. These variations between departments highlight a key element of the controversy regarding prostate biopsies—the lack of standardisation.
One of the study’s major conclusions, however, remains valid and confirms earlier reports. The overall complication rate of transrectal ultrasound guided prostate biopsy remains low (2.7-4.3%).7 This is mainly because of the wide range of use of antibiotics before, during, or after the procedure. The American Urological Association and the European Association of Urology have given no clear recommendations and are awaiting adequate trials. However, fluoroquinolones remain one of the standard drugs in the prophylactic regimen, with 97.3% of men remaining infection free and sepsis free according to the literature,7 confirming earlier results from the European Prostate Cancer Detection study.8
Complications related to transrectal ultrasound guided prostate biopsy are an integral part of the current discussion about PSA screening and early detection, as well as the need for repeat and saturation biopsies. Opponents of screening highlight the high absolute number of complications that would be seen if screening policies were implemented and also question the validity of never ending repeat biopsies that would lead to an exponential increase in morbidity. These concerns are highlighted by the lack of adequate randomised controlled trials. Although worldwide data on prostate biopsies are available, valid conclusions and lessons are rare.
What research is needed to fill the gaps? Half of the patients who harbour infection (febrile urinary tract infections or sepsis) are diagnosed with fluoroquinolone resistant Escherichia coli, so more studies are needed in this subgroup to assess the impact of resistance to these drugs. However, morbidity related to transrectal ultrasound guided prostate biopsy should not be used as an argument against screening and early detection. Randomised trials that have evaluated the optimal regimen, dosage, and timing of antibiotics are lacking, but with the infection-free rate currently standing at 97%, studies investigating these aspects are unlikely to be conducted in the near future.
Rosario and colleagues’ study also shows that outcomes largely depend on who performs the procedure and how skilled they are at doing it. At first glance it looks like local anaesthesia is useful for all patients, but on reflection it is clear that some patients with a smaller number of cores may not need it, and that a dedicated staff—having adequately informed the patient—may be more effective at preventing pain than local anaesthesia.9
In addition, individual biopsy planning, the number of cores samples, the direction of the biopsy needle, and target identification are far from standardised, and this is reflected in the large variation in cancer detection seen in Rosario and colleagues’ study (23% (95% confidence interval 14% to 36%) to 53% (40% to 65%) across the eight centres).
Nomograms, such as the Vienna nomogram, or risk calculators, such as the Prostate Cancer Prevention Trial risk calculator, may help to individualise prostate biopsies according to the patient’s characteristics and symptoms. Pain and discomfort are largely subjective, so protocols and standardised questionnaires, as used in the current study, and adequate patient counselling, will decrease patient discomfort and increase patient compliance with respect to further strategies and treatment decisions.
Cite this as: BMJ 2012;344:d8201
Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Provenance and peer review: Commissioned; not externally peer reviewed.