In-bore MRI interventions: current status and future applications

Targeted biopsy: benefits and limitations

PURPOSE OF REVIEW

To review the current literature regarding the role of multiparametric MRI and fusion-guided biopsies in urologic practice.

RECENT FINDINGS

Fusion biopsies consistently show an increase in the detection of clinically significant cancers and decrease in low-risk disease that may be more suitable for active surveillance. Although, when to incorporate multiparametric MRI into workup is not clearly agreed upon, studies have shown a clear benefit in both biopsy naïve and those with prior negative biopsies in determining the appropriate treatment strategy. More recently, cost-analysis models have been published that show that upfront MRIs are more cost-effective when considering missed cancers and treatment courses.

SUMMARY

With improved accuracy over systematic biopsies, fusion biopsies are a superior method for detection of the true grade of cancer for both biopsy naïve and patients with prior negative biopsies, choosing appropriate candidates for active surveillance, and monitoring progression on active surveillance.

Which technology to select for primary focal treatment of prostate cancer?-European Section of Urotechnology (ESUT) position statement

BACKGROUND

With growing interest in focal therapy (FT) of prostate cancer (PCa) there is an increasing armamentarium of treatment modalities including high-intensity focused ultrasound (HIFU), cryotherapy, focal laser ablation (FLA), irreversible electroporation (IRE), vascular targeted photodynamic therapy (VTP), focal brachytherapy (FBT) and stereotactic ablative radiotherapy (SABR). Currently there are no clear recommendations as to which of these technologies are appropriate for individual patient characteristics. Our intention was to review the literature for special aspects of the different technologies that might be of advantage depending on individual patient and tumour characteristics.

METHODS

The current literature on FT was screened for the following factors: morbidity, repeatability, tumour risk category, tumour location, tumour size and prostate volume and anatomical issues. The ESUT expert panel arrived at consensus regarding a position statement on a structured pathway for available FT technologies based on a combination of the literature and expert opinion.

RESULTS

Side effects were low across different studies and FT modalities with urinary continence rates of 90-100% and erectile dysfunction between 5 and 52%. Short to medium cancer control based on post-treatment biopsies were variable between ablative modalities. Expert consensus suggested that posterior lesions are better amenable to FT using HIFU. Cryotherapy provides best possible outcomes for anterior tumours. Apical lesions, when treated with FBT, may yield the least urethral morbidity.

CONCLUSIONS

Further prospective trials are required to assess medium to long term disease control of different ablative modalities for FT. Amongst different available FT modalities our ESUT expert consensus suggests that some may be better for diffe`rent tumour locations. Tumour risk, tumour size, tumour location, and prostate volume are all important factors to consider and might aid in designing future FT trials.

Therapeutic Ultrasound and Prostate Cancer

Therapeutic ultrasound approaches including high-intensity focused ultrasound (HIFU) are emerging as popular minimally invasive alternative treatments for localized, low-to-intermediate risk prostate cancer. FDA approval was recently granted for two ultrasound-guided HIFU devices. Clinical trials for devices using MRI guidance are ongoing. The current level of evidence for whole-gland ultrasound ablation suggests that its clinical efficacy and adverse event rates including erectile dysfunction and urinary incontinence are similar to current definitive therapies such as radical prostatectomy and external-beam radiotherapy. Short-term data suggest that more focal therapy could reduce the rates of adverse events.

A Case of In-Bore Transperineal MRI-Guided Prostate Biopsy of a Patient with Ileal Pouch-Anal Anastomosis

Ulcerative colitis (UC) is an inflammatory disease that specifically affects the colon. Ulcerative colitis is primarily treated medically and refractory disease is treated with proctocolectomy and ileal pouch-anal anastomosis (IPAA). Gastroenterologists advise against digital rectal exams, pelvic radiation therapy, and transrectal ultrasound (TRUS) biopsies of the prostates of ileal pouch-anal anastomosis patients. Any form of pouch manipulation can lead to severe bleeding, inflammation, and pain. Urologists are therefore faced with the challenge of doing a prostate biopsy without a transrectal ultrasound. We report the rare case of a patient with an ileal pouch-anal anastomosis who underwent in-bore transperineal MRI-guided biopsy of the prostate.

MRI-guided biopsies and minimally invasive therapy for prostate cancer

Recent advances in multiparametric magnetic resonance imaging (mp-MRI) have led to a paradigm shift in the diagnosis and management of prostate cancer (PCa). Its sensitivity in detecting clinically significant cancer and the ability to localize the tumor within the prostate gland has opened up discussion on targeted diagnosis and therapy in PCa. Use of mp-MRI in conjunction with prostate-specific antigen followed by targeted biopsy allows for a better diagnostic pathway than transrectal ultrasound (TRUS) biopsy and improves the diagnosis of PCa. Improved detection of PCa by mp-MRI has also opened up opportunities for focal therapy within the organ while reducing the incidence of side-effects associated with the radical treatment methods for PCa. This review discusses the evidence and techniques for in-bore MRI-guided prostate biopsy and provides an update on the status of MRI-guided targeted focal therapy in PCa.