A method is proposed by which patient specific pretreatment calculations could be used to overcome the aberration and therefore make ultrasound treatment possible.

Background: MRI-guided transurethral ultrasound ablation (TULSA) has been evaluated for organ-confined prostate cancer (PCa). The purpose of this study was to assess the safety and toxicity, accuracy and short-term evolution of cell-death after lesion-targeted TULSA. Methods: This prospective, registered, Phase-I treat-and-3-week-resect-study enrolled six patients with MRI-visible-biopsy-concordant PCa. Lesions were targeted using TULSA with radical intent, except near neurovascular bundles (NVB). Robot-assisted-laparoscopic-prostatectomy (RALP) was performed at 3 weeks. Post-TULSA assessments included MRI (1 and 3 weeks), adverse events and quality-of-life (QoL) to 3 weeks, followed by RALP and whole-mount-histology. Treatment accuracy and demarcation of thermal injury were assessed using MRI and histology. Results: Six patients (median age ¼ 70 years, prostate volume ¼ 60 ml, PSA ¼ 8.9 ng/ml) with eight biopsy-confirmed MRI-lesions (PIRADS 3) were TULSA-treated without complications (median sonication and MRI-times of 17 and 117 min). Foley-catheter removal was uneventful at 2-3 days. Compared to baseline, no differences in QoL were noted at 3 weeks. During follow-up, MRI-derived non-perfused-volume covered ablated targets and increased 36% by 3 weeks, correlating with necrosis-area on histology. Mean histological demarcation between complete necrosis and outer-limit-ofthermal-injury was 1.7 ± 0.4 mm. Coagulation necrosis extended to capsule except near NVB, where 3 mm safety-margins were applied. RALPs were uncomplicated and histopathology showed no viable cancer within the ablated tumor-containing target. Conclusions: Lesion-targeted TULSA demonstrates accurate and safe ablation of PCa. A significant increase of post-TULSA non-perfused-volume was observed during 3 weeks follow-up concordant with necrosis on histology. TULSA achieved coagulation necrosis of all targeted tissues. A limitation of this treat-and-resect-study-design was conservative treatment near NVB in patients scheduled for RALP.

The study aim was to utilise multiple feature selection methods in order to select the most important parameters from clinical patient data for high-intensity focused ultrasound (HIFU) treatment outcome classification in uterine fibroids. The study was retrospective using patient data from 66 HIFU treatments with 89 uterine fibroids. A total of 39 features were extracted from the patient data and 14 different filter-based feature selection methods were used to select the most informative features. The selected features were then used in a support vector classification (SVC) model to evaluate the performance of these parameters in predicting HIFU therapy outcome. The therapy outcome was defined as non-perfused volume (NPV) ratio in three classes: <30%, 30–80% or >80%. The ten most highly ranked features in order were: fibroid diameter, subcutaneous fat thickness, fibroid volume, fibroid distance, Funaki type I, fundus location, gravidity, Funaki type III, submucosal fibroid type and urinary symptoms. The maximum F1-micro classification score was 0.63 using the top ten features from Mutual Information Maximisation (MIM) and Joint Mutual Information (JMI) feature selection methods. Classification performance of HIFU therapy outcome prediction in uterine fibroids is highly dependent on the chosen feature set which should be determined prior using different classifiers.

Background Up to half of all men who undergo primary radiotherapy for localized prostate cancer (PCa) experience local recurrence. Objective To evaluate the safety and early functional and oncological outcomes of salvage magnetic resonance imaging–guided transurethral ultrasound ablation (sTULSA) for men with localized radiorecurrent PCa. Design, setting, and participants This prospective, single-center phase 1 study ( NCT03350529 ) enrolled men with biopsy-proven localized PCa recurrence after radiotherapy. Multiparametric magnetic resonance imaging (mpMRI) and 18 F prostate-specific membrane antigen-1007 ( 18 F PSMA-1007) positron emission tomography (PET)-computed tomography (CT) were used to confirm organ-confined disease localization. Patients underwent either whole-gland or partial sTULSA, depending on their individual tumor characteristics. Outcome measurements and statistical analysis Patients were followed at 3-mo intervals. Adverse events (AEs, Clavien-Dindo scale), functional status questionnaires (Expanded Prostate Cancer Index [EPIC]-26, International Prostate Symptom Score, International Index of Erectile Function-5), uroflowmetry, and prostate-specific antigen (PSA) were assessed at every visit. Disease control was assessed at 1 yr using mpMRI and 18 F-PSMA-1007 PET-CT, followed by prostate biopsies. Results and limitations Eleven patients (median age 69 yr, interquartile range [IQR] 68–74) underwent sTULSA (3 whole-gland, 8 partial sTULSA) and have completed 12-mo follow-up. Median PSA was 7.6 ng/ml (IQR 4.9–10) and the median time from initial PCa diagnosis to sTULSA was 11 yr (IQR 9.5–13). One grade 3 and three grade 2 AEs were reported, related to urinary retention and infection. Patients reported a modest degradation in functional status, most significantly a 20% decline in the EPIC-26 irritative/obstructive domain at 12 mo. A decline in maximum flow rate (24%) was also observed. At 1 yr, 10/11 patients were free of any PCa in the targeted ablation zone, with two out-of-field recurrences. Limitations include the nonrandomized design, limited sample size, and short-term oncological outcomes. Conclusions sTULSA appears to be safe and feasible for ablation of radiorecurrent PCa, offering encouraging preliminary oncological control. Patient summary We present safety and 1-yr functional and oncological outcomes of magnetic resonance imaging–guided transurethral ultrasound ablation (TULSA) as a salvage treatment for local prostate cancer recurrence after primary radiation. Salvage TULSA is safe and shows the ability to effectively ablate prostate cancer recurrence, with acceptable toxicity.