The concept of ideal tumor surgery is to remove the neoplastic tissue without damaging adjacent normal structures. High-intensity focused ultrasound (HIFU) was developed in the 1940s as a viable thermal tissue ablation approach. In clinical practice, HIFU has been applied to treat a variety of solid benign and malignant lesions, including pancreas, liver, prostate, and breast carcinomas, soft tissue sarcomas, and uterine fibroids. More recently, magnetic resonance guidance has been applied for treatment monitoring during focused ultrasound procedures (magnetic resonance-guided focused ultrasound, MRgFUS). Intraoperative magnetic resonance imaging provides the best possible tumor extension and dynamic control of energy deposition using real-time magnetic resonance imaging thermometry. We introduce the fundamental principles and clinical indications of the MRgFUS technique; we also report different treatment options and personal outcomes.

Magnetic resonance (MR) imaging-guided focused ultrasound is an alternative noninvasive method for reducing the pain in skeletal metastases. MR imaging-guided focused ultrasound ablation offers several key advantages over other noninvasive treatment modalities. This technology enables the performance of three-dimensional treatment planning with MR imaging and continuous temperature mapping of treated tissue by using MR thermometry, thereby enabling real-time monitoring of thermal damage in the target zone. The concentration of acoustic energy on the intact surface of cortical bone produces a rapid temperature increase that mediates critical thermal damage to the adjacent periosteum, the most innervated component of mature bone tissue. Such thermal ablation has been shown to be an extremely effective approach for pain management. Energy delivered during MR imaging-guided focused ultrasound ablation and accumulated inside the pathologic soft tissue of the metastases can create a variable amount of tissue necrosis. This technique has also a potential role in achieving local tumor control, allowing remineralization of trabecular bone or reduction in lesion size. The current report presents a detailed step-by-step guide for performing MR imaging-guided focused ultrasound ablation of bone metastases, including use of MR thermometry for monitoring treatment, protocol selection for simple palliation of pain or for local tumor control, and a description of imaging features of periosteal neurolysis or metastasis ablation. Two case studies are also presented: in the first, the technique provided palliation of pain in bone metastases, and in the second, the technique achieved tumor control as further proof of primary efficacy. MR imaging-guided focused ultrasound ablation is a promising method for successful palliation of bone metastasis pain and tumor control, because of the bony structure remodeling induced by thermo-related coagulative necrosis.

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Background: The major endovascular mechanic thrombectomy (MT) techniques are: Stent-Retriever (SR), aspiration first pass technique (ADAPT) and Solumbra (Aspiration + SR), which are interchangeable (defined as switching strategy (SS)). The purpose of this study is to report the added value of switching from ADAPT to Solumbra in unsuccessful revascularization stroke patients. Methods: This is a retrospective, single center, pragmatic, cohort study. From December 2017 to November 2019, 935 consecutive patients were admitted to the Stroke Unit and 176/935 (18.8%) were eligible for MT. In 135/176 (76.7%) patients, ADAPT was used as the first-line strategy. SS was defined as the difference between first technique adopted and the final technique. Revascularization was evaluated with modified Thrombolysis In Cerebral Infarction (TICI) with success defined as mTICI ≥ 2b. Procedural time (PT) and time to reperfusion (TTR) were recorded. Results: Stroke involved: Anterior circulation in 121/135 (89.6%) patients and posterior circulation in 14/135 (10.4%) patients. ADAPT was the most common first-line technique vs. both SR and Solumbra (135/176 (76.7%) vs. 10/176 (5.7%) vs. 31/176 (17.6%), respectively). In 28/135 (20.7%) patients, the mTICI was ≤ 2a requiring switch to Solumbra. The vessel’s diameter positively predicted SS result (Odd Ratio [OR] 1.12, Confidence of Interval [CI] 95% 1.03–1.22; p = 0.006). The mean number of passes before SS was 2.0 ± 1.2. ADAPT to Solumbra improved successful revascularization by 13.3% (107/135 (79.3%) vs. 125/135 (92.6%)). PT was superior for SS comparing with ADAPT (71.1 min (CI 95% 53.2–109.0) vs. 40.0 min (CI 95% 35.0–45.2); p = 0.0004), although, TTR was similar (324.1 min (CI 95% 311.4–387.0) vs. 311.4 min (CI 95% 285.5–338.7); p = 0.23). Conclusion: Successful revascularization was improved by 13.3% after switching form ADAPT to Solumbra (final mTICI ≥ 2b was 92.6%). Vessel’s diameter positively predicted recourse to SS.

Backgroundto evaluate the role of a risk stratification system in intermediate-risk prostate cancer (PCa) treated with hypofractionated radiotherapy (HyRT).Methods131 patients affected by intermediate-risk PCa were treated with HyRT at the total dose of 54,75 Gy in 15 fraction plus 9 months of androgen deprivation therapy (ADT). Patients were classified as favourable risk (FIR) if they had a single NCCN intermediate-risk factor (IRF), a Gleason score ≤3 + 4 = 7, and <50 % of biopsy cores containing cancer (PBCC). If these criteria were not met were classified as unfavourable risk (UIR). Univariate and multivariate analyses using Cox proportional hazards model were calculated for biochemical recurrence-free survival (bRFS), the risk of local recurrence and metastasis-free survival (MFS).ResultsAfter a median follow-up of 56.7 months (range 9.8 to 93.7 months), 11 patients (8.4 %) died, of whom 2 (1.5 %) for PCa. In the univariate analysis, Gleason score, PPBCs, IRFs and PSA at first follow-up were prognostic factors for bRFS and LF while Gleason score, PPBCs and PSA at first follow-up were significant predictor for MFS. In the multivariate analysis only the PSA at first follow-up resulted a prognostic factor for bRFS and MFS. Patients with a value of PSA at first follow-up <0.7 ng/mL respect to those with PSA ≥0,7 ng/mL had a 5y-bRFS of 93.3 % vs. 57.5 %, 5y-MFS of 99.0 % vs. 78.9 % and 5y-LF of 5.8 % vs. 38.3 %. Patients in the UIR PCa group with a PSA value <0.7 ng/mL at first follow-up had significant better bRFS, LF and MFS.ConclusionsRisk factors currently not included in the guidelines are useful to stratify patients with intermediate-risk PCa in two groups of different prognosis even when HyRT is delivered. PSA at first follow-up is useful in UIR PCa to guide the overall length of ADT.