Prostate biopsy is a common and invasive diagnostic method. Globally, more than 3 million prostate biopsies are performed each year, for an annual cancer incidence of 1.4 million cases (1). The first biopsy detects prostate cancer in more than half of suspected patients. In case the initial biopsy is normal, repeat biopsies may be performed as part of active surveillance. Transrectal prostate biopsy is the most commonly used technique and requires the administration of antibiotics to prevent infection.
Transperineal biopsy
Transperineal biopsy under local anesthesia is another alternative approach that is increasingly used. With this approach, the needle passes through the skin of the perineum. Although there are potential advantages to transperineal biopsy (in particular, it does not require, in the majority of cases, prophylactic antibiotic therapy), scientific evidence of its usefulness, compared to the reference technique, is limited. Studies on transperineal biopsies had shown no increase in infectious complications, with or without antibiotic prophylaxis, but there was no comparison with transrectal biopsies in these studies (2).
A single-center clinical trial published in 2024 (ProBE-PC trial), did not demonstrate a difference in the infection rate between transperineal biopsy without prophylaxis and transrectal biopsy with prophylaxis, but infections that were not linked to biopsy had been observed, and patients with recent prostatitis had not been excluded, all of which limited the validity of this study (3).
PREVENT, a multicenter randomized clinical trial
American researchers have just published the results of a clinical trial whose main objective was to compare the occurrence of infectious complications when performing transperineal biopsy without antibiotic prophylaxis compared to transrectal biopsy with targeted prophylaxis (4, 5).
This is a multicenter randomized clinical trial (10 centers) conducted between 2021 and 2024 in the United States. Patients suspected of having prostate cancer were randomized to receive either a transperineal biopsy (without antibiotic prophylaxis) or a transrectal biopsy with targeted prophylaxis (screening by rectal culture for fluoroquinolone-resistant bacteria and targeting antibiotics).
Were excluded: (i) patients randomized but who did not benefit from a biopsy, and (ii) patients with recent prostatitis due to a higher risk of infection after the biopsy. All participants gave written, informed consent. They were all followed up to 7 days after the biopsy (usual time for the occurrence of a biopsy-related infection).
The primary endpoint was the occurrence of infection after biopsy (including genitourinary infection or urosepsis). Assessment was made independently using a 7-day survey and/or medical record review. Secondary outcomes included: detection of high-grade cancer (Gleason ≥2), non-infectious complications, and assessment of biopsy-related pain and discomfort, through 7th day after biopsy, using a numerical scale (0-10). Statistical analyzes were performed using R version 4.2.2 (R Foundation for Statistical Computing), with p
A low complication rate
Between February 2021 and March 2024, 742 patients were included, including 372 who had a transperineal biopsy, and 370 a transrectal one. High-grade cancer was detected in 55% of patients in the transperineal group compared to 52% in the transrectal group (non-significant difference, p = 0.40). The cancer detection rate was thus similar in the two groups.
In the intention-to-treat analysis, no infections were observed in the transperineal group, compared to 6 infections (1.6%) in the transrectal group (p = 0.02). Rates of other complications were low and similar. Participants in the transperineal arm experienced more intense periprocedural pain (adjusted difference = 0.6 [échelle de 0 à 10]95% CI 0.2-0.9), but the effect was small and was resolved.
Some limitations should be noted. The study only focused on the first biopsy, making it impossible to assess the risk of infection in the event of repeated biopsies. Only targeted prophylaxis was taken into account, whereas in the majority of transrectal biopsies “augmented” prophylaxis is carried out.
This study demonstrated the absence of increased risk of prostate infection when using transperineal biopsy without antibiotic prophylaxis, compared to transrectal biopsy with targeted antibiotic prophylaxis. The prostate cancer detection rate was similar with the use of both biopsy techniques. By eliminating the need for antibiotic prophylaxis, the use of transperineal biopsy improves antibiotic management. According to the authors, transperineal biopsy should become the gold standard for prostate biopsy.
