Percutaneous MR-guided prostate cancer cryoablation technical updates and literature review

Abstract

Prostate cancer (PCa) is the most common malignant tumor in males. The benefits in terms of overall reduction in specific mortality due to the widespread use of Prostate Specific Antigen (PSA) screening and the advancements in the curative treatments (radical prostatectomy or radiotherapy) appear to have reached a plateau. There remains, however, the questions of overdiagnosis and overtreatment of such patients. Currently, the main challenge in the treatment of patients with clinically organ-confined PCa is to offer an oncologically efficient treatment with as little morbidity as possible. Amongst the arising novel curative techniques for PCa, cryoablation (CA) is the most established one, which is also included in the NICE and AUA guidelines. CA is commonly performed under ultrasound guidance with the inherent limitations associated with this technique. The recent advancements in MRI have significantly improved the accuracy of detecting and characterizing a clinically significant PCa. This, alongside the development of wide bore interventional MR scanners, has opened the pathway for in bore PCa treatment. Under MRI guidance, PCa CA can be used either as a standard whole gland treatment or as a tumor targeted one. With MR-fluoroscopy, needle guidance capability, multiplanar and real-time visualization of the iceball, MRI eliminates the inherent limitations of ultrasound guidance and can potentially lead to a lower rate of local complications. The aim of this review article is to provide an overview about PCa CA with a more specific insight on MR guided PCa CA; the limitations, challenges and applications of this novel technique will be discussed.

Measurement of sub‐zero temperatures in MRI using T1 temperature sensitive soft silicone materials: Applications for MRI‐guided cryosurgery

“…Recently, there has been increased interest in MRI‐guided thermal therapies where tumors are destroyed by freezing instead of heating. MRI‐guided cryoablation is an interventional procedure which kills tumors by freezing 7–11 . Cryoablation locally freezes the tumor, creating an ice ball (see Figure 1), and results in direct damage to tumor cells by a repeated process of freezing and thawing.…”

Heat Modulation of Intrinsic MR Contrasts for Tumor Characterization

“…Several techniques can be used to induce temperature changes in vivo, including superficial and deep radiofrequency hyperthermia, MR-guided high-intensity focused ultrasound, microwave and laser ablation devices, and hypothermic methods [ 29 , 30 , 31 , 32 , 33 , 34 ]. Given the data summarized in Table 1 and Figure 5 , statistically significant changes in selected quantitative MRI contrast types were observed in malignant tissue versus surrounding normal tissue over the range of temperatures studied here (26–36 °C).…”

Recent progress in cryoablation cancer therapy and nanoparticles mediated cryoablation

“…The US, MR, and CT images were adapted and reprinted under terms of the CC-BY license from ref. 162 , 163 , and 164 , respectively. Copyright, 2017.…”