Treatment options for patients with prostate cancer vary depending on a number of factors including, but not limited to age, weight, overall health, grade and stage of disease and other medical conditions. Patients diagnosed with intermediate grade prostate cancer face the decision of going on active surveillance or opting for surgery, radiation therapy or hormone therapy. Some patients undergo a combination of therapies for their cancer. These decisions are not easy since the morbidity associated with whole-gland therapy concerns both patients and their partners.Many men and their partners are seeking focal therapy as a solution. In this case study we describe the technical aspects of MR-guided laser interstitial thermal therapy utilizing a trans-rectal approach with real-time thermometry feedback. The patient underwent multiparametric MRI (MPMRI) following a positive trans-rectal ultrasound (TRUS)-guided biopsy in the left side of the gland and persistently rising PSA utilizing a 3Tesla MR scanner (TimTrio, Siemens, Erlangen, Germany). A lesion was identified in the anterior aspect of the prostate gland on the left (figure 1 above).
We only did an MRI guided ablation as the patient already came in with a TRUS biopsy result revealing a Gleason 6 (3+3) adenocarcinoma. The target lesion was approached for treatment under MRI-guidance with a trans-rectal approach utilizing computer-aided detection software and interventional planning hardware (DynaCAD, DynaTRIM, Invivo, Pewaukee, WI). (Figure 2)
A needle sleeve was inserted into the patient’s rectum and calibrated to the software off a sagittal high resolution T2-weighted image (figure 3).
Axial T2-weighted images were used to target the lesion and adjust the needle-guide in the left/right, anterior/posterior. Head/foot directions to achieve the target for biopsy were assessed on intraprocedural sagittal scans.The transrectal approach was used to insert a 980 nm diode laser applicator to the center of the target lesion. Under conscious sedation, a test dose of laser energy was administered to confirm the placement of the applicator. The lesion was then ablated for approximately three minutes (figure 4). The lesion was successfully ablated until the apparent diffusion coefficient (ADC) map abnormality disappeared and the kinetic curve demonstrated no wash-in/wash-out.Sherif G. Nour, MD, FRCR, is associate professor of radiology and imaging sciences and director of theInterventional MRI Program at Emory University Hospitals and School of Medicine.