New Research: Exploring the implications of Transrectal Prostate Biopsies
With continuous developments in the field of prostate cancer, such as diagnosis and treatment innovations, we are witnessing a rise in research studies being published which explore these new methodologies, and comparing these to traditional procedures.
Prostate cancer is mainly diagnosed and monitored through repeated prostate biopsies, and have historically been most commonly performed as a TRUS guided transrectal biopsy (TRbx,) using a biopsy needle to puncture the prostate. However, this procedure may cause infection, with high rates of sepsis, as well as inaccurate identification of potential cancer cells. Preventative measures (rectal cleansing, targeted antibiotic prophylaxis e.g) have been introduced to reduce these side effects from occurring, but despite this, the incidence of post-transrectal biopsy infections is rising.
The latest study titled ‘Rate and characteristics of infection after transrectal prostate biopsy: a retrospective observational study’ by Andreas Forsvall, Hannah Jönsson, Magnus Wagenius, Ola Bratt & Adam Linder, assesses the incidence of infection after transrectal prostate biopsy in more detail, and we have highlighted the key findings below.
The study’s primary aim was to evaluate the rate of post-TRbx infections, and this was done by evaluating all transrectal prostate biopsies between October 2017 and March 2019 at two Swedish hospitals (Helsingborg and Angelholm hospitals) serving a geographically defined population of about 300,000 people. Specifically, the patient characteristics included 670 TRbx procedures across 566 men in the country.
Rate of post-biopsy infections
The primary outcome measure was clinical infection after TRbx. Clinical infection was defined as fever (38C) or a positive blood or urine culture within 30 days of TRbx, in combination with manual chart review with clinical suspicion of the infection arising from the urinary tract.
56 TRbx procedures (8.4%) led to the patient seeking medical care within 30 days. The research found a total number of 36 infection episodes after TRbx (5.4% of the 670 TRbx procedures, with an overall risk of 5.4% post-biopsy infection), of whom 26 (3.9%) were admitted to hospital.
9 patients came with infectious symptoms to the urology outpatient clinic or to primary care, and were thereafter managed in outpatient care, and 26 patients were hospitalised, with 0.7% of patients developing sepsis. Four patients were hospitalised multiple times and two had repeated ED visits for recurrent infection after discharge from hospital. Furthermore, three of the four patients sent home after an initial ED visit were later hospitalised due to failure of PO antibiotic treatment.
When undertaking a cost analysis, it was found that the cost of inpatient care was based on the average daily costs for healthcare-associated infections in Region Skåne, Sweden, which was 12,544 SEK in 2015.
Cost analysis was performed for hospitalisations only. With a daily inpatient cost for healthcare- associated infections of USD 1529 (EUR 1,338) and an average hospital stay of 6 days, total direct cost is estimated to be USD 9,174 (EUR 8,031) per hospitalisation.
Post-biopsy infections (in a low AMR situation) occurred in 5.4% of men after TRbx, of which most (3.9%) were hospitalised with infection and some (1.3%) had a complicated infection. The hospital cost of these infections was estimated to be USD 9,174 (EUR 8,031) per hospitalisation. These increasingly common infections may thus not only have severe consequences for the affected patients, but are also difficult to treat, resource-demanding and costly.
Comparison to Other Studies
The results of this specific research are similar to a previous report of sepsis after prostate biopsy, although comparisons are complicated by varying definitions of post-biopsy infection and sepsis. Hospitalisation may be a better outcome measure since it is strongly associated with severe illness, costs and the healthcare resource utilisation.
A study by Lundstrom et al. showed a 1% hospital admission for post-biopsy infection in Sweden between 2006 and 2011, considerably lower than the 3.9% found in the present study. Moreover, another recent Scandinavian study, with a similar design as the present study, reported a 6.1% rate of hospital admissions for infection.
These studies indicate that the risk of hospitalisation for post-TRbx infections may have increased significantly over the past ten years. The rising infection rates are at least partially a consequence of increasing antibiotic resistance. According to the Public Health Agency of Sweden, 12.8% of E. coli in blood cultures in Scania from 2014 were resistant and 0.9% intermediately sensitive to ciprofloxacin.
As new methodologies enter the market, we can expect future research to take place, such as the below research which looks at the freehand technique of Transperineal TP prostate biopsies, where the biopsy needle passes through the perineum, rather than the rectal wall. A study by Ahmet Urkmez, Cihan Demirel, Muammer Altok, Tharakeswara K. Bathala, Daniel D. Shapiro, and John W. Davis is titled “Freehand Versus Grid-Based Transperineal Prostate Biopsy: A Comparison of Anatomic Region Yield and Complications” compares the efficacy and complication rates of the freehand (FH) method with those of the standard grid-based (GB) method.
The freehand technique of transperineal prostate biopsy uses a commercialised needle access system which facilitates a reduction in anesthesia requirements from general to local or local/sedation. For background, the GB method was performed from 2014 to 2018, and the updated freehand technique was performed from 2018 to 2020, yielding comparative cohorts of 174 and 304, respectively. Take a look at a summary of the research findings below:
- The FH and GB techniques demonstrated equivalent yields of Gleason grade group (GGG)-2 prostate cancer (PCa).
- The FH group had a significantly higher mean number of cores with ≥GGG-2 PCa involvement (p=0.011) but a significantly lower mean number of biopsy samples (p <0.01).
- The urinary retention rate of the GB group (10%) was significantly higher than that of the FH group (1%; p <0.01).
- The rates of ≥GGG-2 PCa involvement in the anterior (GB, 31%) and anteromedial (FH, 22%) sectors were higher than those in other sectors (range, 0-9%).
- For multiparametric MRI, the rate of ≥GGG-2 PCa detection in the anteromedial prostate (23%) was nearly half that in other locations (range, 38-55%).
Compared with GB TP biopsy, FH TP biopsy demonstrates an equivalent cancer yield with no risk of sepsis, a significantly reduced risk of urinary retention, and reduced anesthesia needs. The higher number of cores with ≥GGG-2 PCa involvement in the FH group suggests that FH TP biopsy can sample the prostate better than GB-TP biopsy can.
As prostate biopsy techniques and methodologies advance, it is imperative that not just medical professionals, but wider stakeholders in the healthcare system, pay attention to the increasing body of evidence which indicates that not only is freehand transperineal biopsy a preferable method for sampling of the prostate – and therefore more accurate cancer detection – but also reduced complications which can lead to patient discomfort and hospitalisation.
The outcomes are a better patient experience and outcomes; reduced costs through theatre time and anaesthesia; and a reduction in “hidden” costs through post-biopsy related infections and sepsis. It’s time to take a holistic view of the benefits of FH LA TP biopsy.