MRI-based radiomics to predict lipomatous soft tissue tumors malignancy: a pilot study.

OBJECTIVES: To develop and validate a MRI-based radiomic method to predict malignancies in lipomatous soft tissue tumors. METHODS: This retrospective study searched in the database of our pathology department, data from patients with lipomatous soft tissue tumors, with histology and gadolinium-contrast enhanced T1w MR images, obtained from 56 centers with non-uniform protocols. For each tumor, 87 radiomic features were extracted by two independent observers to evaluate the inter-observer reproducibility. A reduction of learning base dimension was performed from reproducibility and relevancy criteria. A model was subsequently prototyped using a linear support vector machine to predict malignant lesions. RESULTS: Eighty-one subjects with lipomatous soft tissue tumors including 40 lipomas and 41 atypical lipomatous tumors or well-differentiated liposarcomas with fat-suppressed T1w contrast enhanced MR images available were retrospectively enrolled. Based on a Pearson's correlation coefficient threshold at 0.8, 55 out of 87 (63.2%) radiomic features were considered reproducible. Further introduction of relevancy finally selected 35 radiomic features to be integrated in the model. To predict malignant tumors, model diagnostic performances were as follow: AUROC = 0.96; sensitivity = 100%; specificity = 90%; positive predictive value = 90.9%; negative predictive value = 100% and overall accuracy = 95.0%. CONCLUSION: This work demonstrates that radiomics allows to predict malignancy in soft tissue lipomatous tumors with routinely used MR acquisition in clinical oncology. These encouraging results need to be further confirmed in an external validation population.

Combined Laparoscopic Revision of the Gastric Pouch and Distalization of the Roux Limb After Failure of Weight Loss Following Roux-en-Y Gastric Bypass.

PURPOSE: After failed Roux-en-Y gastric bypass (RYGB), the choice of a secondary procedure falls into many pathways: revision of the gastric pouch, distalization of the bypass (DRYGB), addition of an adjustable gastric band, and conversion to a duodenal switch (BPD/DS). MATERIAL AND METHODS: We present the case of a 54-year-old man with initial BMI of 51.5 kg/m2, who first underwent laparoscopic sleeve gastrectomy (SG) in 2010. In 2012, he underwent a RYGB procedure, and in 2015, a pouch resizing for weight regain. In 2018, he reached a BMI of 41.2 kg/m2. A 3D volumetric CT scan measured a gastric pouch volume of 220 cm3 and a gastrojejunal anastomosis diameter of 20 mm. RESULTS: As shown in the video, the patient underwent a combined revision of the gastric pouch and the gastrojejunal anastomosis associated to the distalization of the Roux limb. The gastrojejunal anastomosis is identified, and vertical division of the stomach is performed along a 36 French bougie, in order to create a 30 cm3 gastric pouch. Then, the jejunojejunal anastomosis is identified, and the Roux limb at the jejunojejunostomy is divided and transposed distally 100 cm to create a total alimentary length of 250 cm. The postoperative course was uneventful. At 1 year, his BMI was 31.2 kg/m2. No nutritional deficiencies were noted. CONCLUSION: Combined laparoscopic pouch resizing and distalization are safe and can lead to adequate weight loss. This technique allows the combination of an added restriction and malabsorption to the previous RYGB and could lead to an improved weight loss.

Local Control and Analgesic Efficacy of Percutaneous Cryoablation for Desmoid Tumors.

OBJECTIVE: Cryoablation is being more and more often used to treat desmoid tumors. We report our experience of cryoablation as a local and analgesic treatment for inoperable or recurring desmoid tumors. METHODS: This study includes 34 patients who underwent percutaneous cryoablation of 41 desmoid tumors between July 2012 and September 2016. All patients underwent pain assessment using a visual analog scale (VAS) and preoperative imaging. All cryoablation procedures were performed using the same cryoablation system. Patients received clinical and radiological follow-up at 6 months post-procedure, with pain-rating and adverse events being recorded. A long-term follow-up was achieved until 31 December 2018. Disease-free survival at 3 years was also recorded. Radiological tumor response was determined by tumor measurements using RECIST 1.1. RESULTS: Twelve patients benefitted from curative treatment on 100% of the tumor volume, but 22 patients received debulking treatment because of the risk of neighboring structures. Two patients had a postoperative hematoma grade 2 of the CIRSE classification system for complications, and two patients had grade 4 complications involving palsy of the common fibular nerve. Disease-free survival at 3 years was 42.2%. The mean VAS pain scores were 5.7 and 2.4 at pretreatment and 6 months, respectively, showing a mean reduction of 3.3 (p < 0.001). At 6 months, all measured tumor dimensions were significantly lower than pretreatment. CONCLUSION: Cryoablation is an effective therapeutic option for the local treatment and for the analgesic management of desmoid tumors.