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BACKGROUND: The rising prevalence of insulin resistance (IR), metabolic syndrome, and type 2 diabetes are associated with increases in abdominal mesenteric fat. Adipocytes are sensitive to low temperatures, making cryolipolysis of mesenteric fat an attractive treatment modality to potentially reduce IR. OBJECTIVES: We aimed to determine whether (1) cryolipolysis is safe in reducing the volume of the mesenteric fat and (2) reduction in mesenteric fat volume reduces indices of IR and glycemic dysfunction. SETTING: Indiana University School of Medicine. METHODS: A novel cooling device and method delivered cryolipolysis in a controlled manner to avoid tissue ablative temperatures. Ossabaw pigs (n = 8) were fed a high-fat diet for 9 months to develop visceral obesity, IR, and metabolic syndrome. Following laparotomy, mesenteric fat cryolipolysis (MFC) was performed in 5 pigs, while 3 served as sham surgery controls. The volume of the mesenteric fat was measured by computed tomography and compared with indices of glucose intolerance before and at 3 and 6 months postprocedure. RESULTS: MFC safely reduced mesenteric fat volume by ∼30% at 3 months, which was maintained at 6 months. Body weight did not change in either the MFC or sham surgery control groups. Measure of glycemic control, insulin sensitivity, and blood pressure significantly improved after MFC compared with sham controls. CONCLUSION: MFC reduces the volume of mesenteric fat and improves glycemic control in obese, IR Ossabaw pigs, without adverse effects.

PURPOSE: To assess the clinical effectiveness of cryoablation for palliation of painful bone metastases. MATERIALS AND METHODS: MOTION (Multicenter Study of Cryoablation for Palliation of Painful Bone Metastases) (ClinicalTrials.gov NCT02511678) was a multicenter, prospective, single-arm study of adults with metastatic bone disease who were not candidates for or had not benefited from standard therapy, that took place from February 2016 to March 2018. At baseline, participants rated their pain using the Brief Pain Inventory-Short Form (reference range from 0 to 10 points); those with moderate to severe pain, who had at least one metastatic candidate tumor for ablation, were included. The primary effectiveness endpoint was change in pain score from baseline to week 8. Participants were followed for 24 weeks after treatment. Statistical analyses included descriptive statistics and logistic regression to evaluate changes in pain score over the postprocedure follow-up period. RESULTS: A total of 66 participants (mean age, 60.8 years ± 14.3 [standard deviation]; 35 [53.0%] men) were enrolled and received cryoablation; 65 completed follow-up. Mean change in pain score from baseline to week 8 was -2.61 points (95% CI: -3.45, -1.78). Mean pain scores improved by 2 points at week 1 and reached clinically meaningful levels (more than a 2-point decrease) after week 8; scores continued to improve throughout follow-up. Quality of life improved, opioid doses were stabilized, and functional status was maintained over 6 months. Serious adverse events occurred in three participants. CONCLUSION: Cryoablation of metastatic bone tumors provided rapid and durable pain palliation, improved quality of life, and offered an alternative to opioids for pain control.Keywords: Ablation Techniques, Metastases, Pain Management, Radiation Therapy/OncologySupplemental material is available for this article.© RSNA, 2021.

Image-guided tumor ablation has become a well-established hallmark of local cancer therapy. The breadth of options available in this growing field increases the need for standardization of terminology and reporting criteria to facilitate effective communication of ideas and appropriate comparison among treatments that use different technologies, such as chemical (eg, ethanol or acetic acid) ablation, thermal therapies (eg, radiofrequency, laser, microwave, focused ultrasound, and cryoablation) and newer ablative modalities such as irreversible electroporation. This updated consensus document provides a framework that will facilitate the clearest communication among investigators regarding ablative technologies. An appropriate vehicle is proposed for reporting the various aspects of image-guided ablation therapy including classification of therapies, procedure terms, descriptors of imaging guidance, and terminology for imaging and pathologic findings. Methods are addressed for standardizing reporting of technique, follow-up, complications, and clinical results. As noted in the original document from 2003, adherence to the recommendations will improve the precision of communications in this field, leading to more accurate comparison of technologies and results, and ultimately to improved patient outcomes.

Purpose: To retrospectively assess long-term outcomes of percutaneous renal cryoablation, including factors affecting complications and local recurrence rates.Materials and Methods: A total of 357 computed tomographic (CT) fluoroscopy-guided percutaneous cryoablation procedures were performed for 382 masses in 302 outpatients; 347 were biopsy-proven renal-cell carcinoma (RCC) or Bosniak category > III masses (n = 28). Benign pathologic conditions (n = 18) or metastatic non-RCC disease (n = 17) were included to analyze procedural complication rate, but recurrence rates, tumor staging, and nephrometry score were limited to RCCs. The average tumor diameter was 2.9 cm (range, 1-10.3 cm), and median nephrometry score for RCC was 8 (mean, 7.4). Protection of adjacent vital structures was performed in 34% of procedures (n = 121), and ureteral stent placement was performed for 9.2% (n = 33). All major complications were graded per surgical Clavien-Dindo criteria.Results: The average CT-visible cryoablation zone diameter was 5 cm (range, 2.5-10.5 cm). Grade ≥ 3 complications occurred in 2.8% of procedures (n = 10), and appeared related to only high nephrometry scores (P = .0086) and larger tumors (P = .0034). No significant changes in renal function before and after the procedure were noted (P = .18). At a mean follow-up of 31.8 months, the local tumor recurrence rate was 3.2% (11 of 347) for RCC, and no significant difference was noted between tumors larger or smaller than 3 cm (P = .15). The difference reached significance only among the small number of stage ≥ T2 RCC tumors (P = .0039).Conclusions: Long-term follow-up of percutaneous renal cryoablation demonstrates low recurrence rates with preserved renal function, even for patients with high nephrometry scores and body mass index, assuming thorough cytotoxic technique and protection measures. [ABSTRACT FROM AUTHOR]

Purpose: To assess feasibility, complications, local tumor recurrences, overall survival (OS), and estimates of cost effectiveness for multisite cryoablation (MCA) of oligometastatic non-small-cell lung cancer (NSCLC).Materials and Methods: A total of 49 computed tomography- and/or ultrasound-guided percutaneous MCA procedures were performed on 60 tumors in 31 patients (19 women and 12 men) with oligometastatic NSCLC. Average patient age was 65 years. Tumor location was grouped according to common metastatic sites. Median OS was determined by Kaplan-Meier method and defined life-years gained (LYGs). Estimates of MCA costs per LYG were compared with established values for systemic therapies.Results: Total numbers of tumors and cryoablation procedures for each anatomic site were as follows: lung, 20 and 18; liver, nine and seven; superficial, 12 and 11; adrenal, seven and seven; paraaortic/isolated, two and two; and bone, 10 and seven. A mean of 1.6 procedures per patient were performed, with a median clinical follow-up of 11 months. Major complication and local recurrence rates were 8% (four of 49) and 8% (five of 60), respectively. Median OS for MCA was 1.33 years, with an estimated 1-year survival rate of approximately 53%. MCA appeared cost-effective even when added to the cost of best supportive care or systemic regimens, with an adjunctive cost-effectiveness ratio of $49,008-$87,074.Conclusions: MCA was associated with very low morbidity and local tumor recurrence rates for all anatomic sites, and possibly increased OS. Even as an adjunct to systemic therapies, MCA appeared cost-effective for palliation of oligometastatic NSCLC. [ABSTRACT FROM AUTHOR]

Purpose: To assess the effects on the proportions of lethal ice (ie, colder than −30°C) in phantoms with different heat loads created by varying the size and number of cryoprobes spaced 2 cm apart. Materials and Methods: Thermocouples at 0.5-, 1.0-, and 1.5-cm intervals from 1.7- or 2.4-mm-diameter cryoprobes were held by jigs accommodating a maximum of four cryoprobes. Agar phantoms (N = 24) used three sets of baseline temperatures: approximately 6°C, 24°C, and 39°C. Temperatures during 15-minute freeze cycles were correlated with actual thermocouple locations seen within the ice by computed tomography (CT). Diameters and surface areas of the −30°C lethal isotherm were assessed over time as percentages of the overall ice ball. Results: The high–heat load phantom experiments (39°C) showed the greatest impact on lethal zones by percentage for all probe configurations. At 15 minutes, single-, double-, triple-, and quadruple-probe arrangements of 2.4-mm cryoprobes had average lethal ice diameters of 1.2, 3.3, 4.1, and 4.9 cm, respectively, comprising 13%, 46%, 51%, and 56% surface areas of lethal ice, respectively. Surface areas and diameters of lethal ice made by 1.7-mm cryoprobes were 71% and 84% of those made by 2.4-mm cryoprobes, respectively. Lethal ice resides less than 1 cm behind the leading edge for nearly all probe configurations and heat loads. Conclusions: Single cryoprobes create very low percentages of lethal ice. Multiple cryoprobes overcome the high heat load of body temperature phantoms and help compensate for the lower freeze capacity of thinner cryoprobes. [Copyright &y& Elsevier]

The article discusses the approach of author Leif Littrup with his work as teacher of Chinese language and studying the history of Ming dynasty in China. It mentions possible to govern a country and a population the size of China with a fairly small bureaucracy and conducive academic environment. It also mentions material conditions and safety considerations and studies of the military and of violence.