The MSSM confronts the precision electroweak data and the muon g-2

We update the electroweak study of the predictions of the Minimal Supersymmetric Standard Model (MSSM) including the recent results on the muon anomalous magnetic moment, the weak boson masses, and the final precision data on the Z boson parameters from LEP and SLC. We find that the region of the parameter space where the slepton masses are a few hundred GeV is favored from the muon g-2 for \tan\beta \ltsim 10, whereas for \tan\beta \simeq 50 heavier slepton mass up to \sim 1000 GeV can account for the reported 3.2 \sigma difference between its experimental value and the Standard Model (SM) prediction. As for the electroweak measurements, the SM gives a good description, and the sfermions lighter than 200 GeV tend to make the fit worse. We find, however, that sleptons as light as 100 to 200 GeV are favored also from the electroweak data, if we leave out the jet asymmetry data that do not agree with the leptonic asymmetry data. We extend the survey of the preferred MSSM parameters by including the constraints from the b \to s \gamma transition, and find favorable scenarios in the minimal supergravity, gauge-, and mirage-mediation models of supersymmetry breaking.Comment: 40 pages, 12 figures. v2: minor changes, references added, version to appear in JHE

Comparison Between Minimally Invasive Right Anterior and Right Posterior Sectionectomy vs Right Hepatectomy: An International Multicenter Propensity Score-Matched and Coarsened-Exact-Matched Analysis of 1,100 Patients

BACKGROUND: The role of minimally invasive right anterior and right posterior sectionectomy (MI-RAS/ MI-RPS) for right-sided liver lesions remains debatable. Although technically more demand-ing, these procedures might result in faster recovery and lower postoperative morbidity com-pared with minimally invasive right hemihepatectomy. STUDY DESIGN: This is an international multicenter retrospective analysis of 1,114 patients undergoing mini-mally invasive right hemihepatectomy, MI-RAS, and MI-RPS at 21 centers between 2006 and 2019. Minimally invasive surgery included pure laparoscopic, robotic, hand-assisted, or a hybrid approach. A propensity-matched and coarsened-exact-matched analysis was performed. RESULTS: A total of 1,100 cases met study criteria, of whom 759 underwent laparoscopic, 283 robotic, 11 hand-assisted, and 47 laparoscopic-assisted (hybrid) surgery. There were 632 right hemihepatecto-mies, 373 right posterior sectionectomies, and 95 right anterior sectionectomies. There were no dif-ferences in baseline characteristics after matching. In the MI-RAS/MI-RPS group, median blood loss was higher (400 vs 300 mL, p = 0.001) as well as intraoperative blood transfusion rate (19.6% vs 10.7%, p = 0.004). However, the overall morbidity rate was lower including major morbidity (7.1% vs 14.3%, p = 0.007) and reoperation rate (1.4% vs 4.6%, p = 0.029). The rate of close/involved margins was higher in the MI-RAS/MI-RPS group (23.4% vs 8.9%, p < 0.001). These findings were consistent after both propensity and coarsened-exact matching. CONCLUSIONS: Although technically more demanding, MI-RAS/MI-RPS is a valuable alternative for min-imally invasive right hemihepatectomy in right-sided liver lesions with lower postopera-tive morbidity, possibly due to the preservation of parenchyma. However, the rate of close/ involved margins is higher in these procedures. These findings might guide surgeons in preop-erative counselling and in selecting the appropriate procedure for their patients. (C) 2022 by the American College of Surgeons. Published by Wolters Kluwer Health, Inc. All rights reserved.Y

International multicentre propensity score-matched analysis comparing robotic versus laparoscopic right posterior sectionectomy.

BACKGROUND Minimally invasive right posterior sectionectomy (RPS) is a technically challenging procedure. This study was designed to determine outcomes following robotic RPS (R-RPS) and laparoscopic RPS (L-RPS). METHODS An international multicentre retrospective analysis of patients undergoing R-RPS versus those who had purely L-RPS at 21 centres from 2010 to 2019 was performed. Patient demographics, perioperative parameters, and postoperative outcomes were analysed retrospectively from a central database. Propensity score matching (PSM) was performed, with analysis of 1 : 2 and 1 : 1 matched cohorts. RESULTS Three-hundred and forty patients, including 96 who underwent R-RPS and 244 who had L-RPS, met the study criteria and were included. The median operating time was 295 minutes and there were 25 (7.4 per cent) open conversions. Ninety-seven (28.5 per cent) patients had cirrhosis and 56 (16.5 per cent) patients required blood transfusion. Overall postoperative morbidity rate was 22.1 per cent and major morbidity rate was 6.8 per cent. The median postoperative stay was 6 days. After 1 : 1 matching of 88 R-RPS and L-RPS patients, median (i.q.r.) blood loss (200 (100-400) versus 450 (200-900) ml, respectively; P 500 ml; P = 0.001), need for intraoperative blood transfusion (10.2 versus 23.9 per cent, respectively; P = 0.014), and open conversion rate (2.3 versus 11.4 per cent, respectively; P = 0.016) were lower in the R-RPS group. Similar results were found in the 1 : 2 matched groups (66 R-RPS versus 132 L-RPS patients). CONCLUSION R-RPS and L-RPS can be performed in expert centres with good outcomes in well selected patients. R-RPS was associated with reduced blood loss and lower open conversion rates than L-RPS

Minimally invasive liver resection for huge (≥10 cm) tumors: an international multicenter matched cohort study with regression discontinuity analyses.

Background The application and feasibility of minimally invasive liver resection (MILR) for huge liver tumours (≥10 cm) has not been well documented. Methods Retrospective analysis of data on 6,617 patients who had MILR for liver tumours were gathered from 21 international centers between 2009-2019. Huge tumors and large tumors were defined as tumors with a size ≥10.0 cm and 3.0-9.9 cm based on histology, respectively. 1:1 coarsened exact-matching (CEM) and 1:2 Mahalanobis distance-matching (MDM) was performed according to clinically-selected variables. Regression discontinuity analyses were performed as an additional line of sensitivity analysis to estimate local treatment effects at the 10-cm tumor size cutoff. Results Of 2,890 patients with tumours ≥3 cm, there were 205 huge tumors. After 1:1 CEM, 174 huge tumors were matched to 174 large tumors; and after 1:2 MDM, 190 huge tumours were matched to 380 large tumours. There was significantly and consistently increased intraoperative blood loss, frequency in the application of Pringle maneuver, major morbidity and postoperative stay in the huge tumour group compared to the large tumour group after both 1:1 CEM and 1:2 MDM. These findings were reinforced in RD analyses. Intraoperative blood transfusion rate and open conversion rate were significantly higher in the huge tumor group after only 1:2 MDM but not 1:1 CEM. Conclusions MILR for huge tumours can be safely performed in expert centers It is an operation with substantial complexity and high technical requirement, with worse perioperative outcomes compared to MILR for large tumors, therefore judicious patient selection is pivotal