Multiple studies have now documented an increase in the incidence of post-prostate biopsy sepsis. If allowed to continue, this rising source of morbidity may present an argument against prostate-specific antigen (PSA)-based prostate cancer screening and a challenge to the safety of active surveillance protocols. Transperineal prostate biopsy promises a long-term solution to the problem of prostate biopsy-related infections. Transperineal techniques have little to no incidence of infection, with some investigators omitting periprocedural antibiotics altogether [1]. Here, we summarize the improvements in technology and technique that have made transperineal biopsy a viable alternative to transrectal biopsy.
MRI-targeted biopsy is rapidly becoming the standard of care for prostate cancer diagnosis based on its ability to preferentially detect high-grade cancers. This has been recapitulated in the transperineal setting. In a study of patients undergoing transperineal biopsy in which 215 patients had a prebiopsy MRI and 281 patients did not, Washino et al. [2] found that patients who had a prebiopsy MRI (with or without cognitive fusion) had a higher rate of clinically significant cancer detection than those who did not (46.0 vs. 35.2%, respectively; P = 0.016). Similarly, the PICTURE trial assigned 249 men to mpMRI followed by transperineal mapping biopsies, as well as image fusion biopsies in men with a lesion on MRI. This study found that transperineal fusion biopsy agreed with mapping biopsies in the detection of clinically significant cancer in 81% of cases [3]. Another recent study of 1032 men undergoing transperineal MRI fusion and transperineal mapping biopsies had similar findings, with a sensitivity of 83.8% for the detection of clinically significant prostate cancer using a cutoff of PIRADS 3 or greater [4]. Remarkably, this study also demonstrated the safety of transperineal biopsy, with no complications requiring hospital admission in any of those biopsied [4]. Recent industry developments of software to perform transperineal-targeted biopsy are promising. Using the Urofusion software, Kaufmann et al.[5] found that software-assisted transperineal-targeted biopsy was superior to transrectal-targeted biopsy with cognitive fusion for the detection of cancer. Similarly, Kosarek et al. [6] recently reported the use of the transperineal UroNav mpMRI/transrectal ultrasound (TRUS)-targeted biopsy platform, the adoption of which will certainly increase the accessibility of transperineal-targeted biopsy.
Despite these improvements, transperineal biopsy remains uncommon. Although MRI-targeted biopsy use has increased over a 7-year period from 0.2% to 6.5% in 2015, the use of transperineal biopsy has remained stagnant, ranging from 0.4% to 0.7% of biopsies, with the overwhelming majority of biopsies being performed transrectally (93.1%) [7]. The lack of adoption of transperineal biopsy is likely attributable to cost, the perceived need for general anesthesia and physician comfort and training. Recent analysis comparing transperineal biopsy under general anesthesia, transrectal biopsy under sedation and fusion biopsy under sedation to a reference of TRUS with sedation found a cost increase of 153%, 90% and 150%, respectively [8]. The cost of general anesthesia, however, is similar to the cost of a fusion biopsy, suggesting that patient (and physician) preference, not insurance reimbursement, may be a driving factor. The advent of in-office transperineal biopsy without the need for general anesthesia or conscious sedation may very well change this cost paradigm. Thurtle et al.[9] have developed the Cambridge Prostate Biopsy (CAMPROBE) cannula device for the coaxial administration of lidocaine immediately prior to biopsy of tissue which they tested in 30 men who had received prior TRUS biopsies. Men reported decreased pain, and, remarkably, 87% (26 of 30) preferred this modality over transrectal biopsy. Other in-office biopsy reports have demonstrated similar results [1]. Our anecdotal experience reflects similar trends in patient tolerability for in-office transperineal biopsy, provided that patients are well counseled in advance of and during the procedure.
The evidence for transperineal biopsy is mounting. The minimal infectious risk combined with the ability to perform the procedure in-office with MRI fusion is appealing. The learning curve for both success and comfort with this technique is nontrivial, but it is time well spent for conscientious clinicians to add a more efficacious and less morbid procedure to their armamentarium.
Current opinion in urology. 2019 Jan [Epub]
Michael D Gross, Jonathan E Shoag, Jim C Hu
Department of Urology, New York Presbyterian Hospital, Weill Cornell Medical College, New York, New York, USA.