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Objective. FLASH radiotherapy (FLASH-RT) with ultra-high dose rate (UHDR) irradiation (i.e. > 40 Gy s−1) spares the function of normal tissues while preserving antitumor efficacy, known as the FLASH effect. The biological effects after conventional dose rate-radiotherapy (CONV-RT) with ≤0.1 Gy s−1 have been well modeled by considering microdosimetry and DNA repair processes, meanwhile modeling of radiosensitivities under UHDR irradiation is insufficient. Here, we developed an integrated microdosimetric-kinetic (IMK) model for UHDR-irradiation enabling the prediction of surviving fraction after UHDR irradiation. Approach. The IMK model for UHDR-irradiation considers the initial DNA damage yields by the modification of indirect effects under UHDR compared to CONV dose rate. The developed model is based on the linear-quadratic (LQ) nature with the dose and dose square coefficients, considering the reduction of DNA damage yields as a function of dose rate. Main results. The estimate by the developed model could successfully reproduce the in vitro experimental dose–response curve for various cell line types and dose rates. Significance. The developed model would be useful for predicting the biological effects under the UHDR irradiation. [ABSTRACT FROM AUTHOR]

Aim: Patients with malignant tumors are prone to develop nutritional disorders. The Geriatric Nutritional Risk Index (GNRI) is a new prognostic indicator for assessing the nutritional status. This study was performed to evaluate whether the preoperative GNRI can serve as a prognostic factor in patients with intrahepatic cholangiocarcinoma (ICC) undergoing curative surgery. Methods: This study included 123 consecutive patients with ICC who were treated with curative surgery. Kaplan–Meier analysis was performed to calculate the recurrence-free survival (RFS) and overall survival (OS), and Cox regression analysis was used to evaluate prognostic factors. Results: Of the 123 patients, 82 were male and 41 were female. The median age of the patients was 70 years, and the median follow-up period was 37.0 months (interquartile range, 16.2–71.7 months). The patients were classified by the median GNRI into a low GNRI group (GNRI < 105) and high GNRI group (GNRI ≥ 105). The patients in the low GNRI group had a significantly poorer prognosis in terms of RFS and OS than the patients in the high GNRI group (RFS, p = 0.0201; OS, p < 0.0001). Lymph node metastasis [hazard ratio (HR), 4.66; 95% confidence interval (CI), 2.46–8.85], postoperative complications (HR, 2.38; 95% CI, 1.32–4.31), and a low GNRI (HR, 2.53; 95% CI, 1.42–4.50) were independent poor prognostic factors for OS. Conclusion: The GNRI may be a useful prognostic indicator in patients with ICC undergoing curative hepatectomy. [ABSTRACT FROM AUTHOR]

Aim: Severe postoperative pleural effusion (sPOPE) after hepatectomy can lead to respiratory distress and may require thoracic drainage, leading to prolonged hospitalization. Preventive chest tube insertion may be useful for patients at high risk for sPOPE. We aimed to develop a predictive model for sPOPE after hepatectomy and evaluate indications for preventive chest tube insertion using our model. Methods: We evaluated all patients who underwent hepatectomy from 2013 to 2020. Risk factors for sPOPE were used to develop a predictive model for sPOPE, which was validated in a cohort that received preventative chest tube placement postoperatively. Results: A total of 325 patients were analyzed. Thirty‐one (9.5%) patients had a preventive chest tube placed at the end of their operation. Twenty‐one patients out of the remaining 294 patients developed sPOPE. Multivariate analysis identified resection containing segment 8 [relative risk (RR) 3.24, P =.022], intraoperative bleeding ≥ 500 g (RR 4.02, P =.008), intraoperative diaphragmatic incision (RR 6.96, P =.042) and open hepatectomy (RR 7.51, P =.016) as independently associated with sPOPE. The estimated probability of sPOPE ranged from 0.4% in patients with none of these factors to 73.4% in the presence of all factors. Among the 31 patients who received a preventive chest tube, more patients in the high‐risk group defined by the model had postoperative pleural effusions compared to the low‐risk group (P =.012). Conclusion: Our predictive model for sPOPE using four risk factors allows for reliable prediction and may be useful for selection of preventive chest tube in patients undergoing hepatectomy. [ABSTRACT FROM AUTHOR]

Liew and Mairani (2024 Phys. Med. Biol . 69 248001) commented on our previous reply to comments on our paper, 'Modeling for predicting survival fraction of cells after ultra-high dose rate irradiation'. We appreciate their comments on the choice of experimental data on DNA damage for cell survival and agree that the estimate of the dose-response curve on cell survival depends on the selection of DNA damage data. As an additional benchmark test, we compared the relative biological effectiveness (RBE) predicted using the recommended DNA damage data measured in normoxia with those reported in our original paper, and confirmed that the difference in RBE was less than 8%. Although our model allows for the estimation of cell survival and RBE under ultra-high dose rate (UHDR) irradiation, we highlight that a further accumulation of experimental data on DNA damage under UHDR irradiation is necessary for the further development of biophysical models concerning the mechanistical estimation of biological effects., (© 2024 Institute of Physics and Engineering in Medicine. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Purpose Owing to the shortage of surgeons and the decrease in medical staff in regional medical care, reducing unnecessary tests can limit the burden on the staff. In this study, we aimed to examine the predictors of deep vein thrombosis (DVT), such as D-dimer levels in patients who underwent surgery at our hospital, and determine the feasibility of screening in these patients. Knowledge of D-dimer levels can indicate the risk of DVT in patients about to undergo surgery. Methods We retrospectively analyzed 310 of 1,059 surgical cases in which preoperative lower extremity ultrasonography was performed in our department between April 2021 and June 2024. We compared 46 patients with thrombi and 264 patients without thrombi. Results Patients with low body mass indices (<18.5 kg/m 2 ) and high D-dimer levels (> 2 μg/mL) had a significantly higher risk of DVT, whereas patients taking oral antiplatelet drugs or anticoagulants had a significantly lower risk of DVT. The area under the curve for D-dimer levels in predicting DVT was 0.779. D-dimer levels of 2 μg/mL had high sensitivity - (1 - specificity). However, there were three false-negative cases, and the highest D-dimer level that resulted in 100% sensitivity was 1.4 μg/mL. Conclusion Predicting DVT using D-dimer levels may be effective, and considering additional testing based on D-dimer levels and patient background may reduce excessive preoperative testing., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Amakusa Regional Medical Center Hospital Ethics Committee issued approval 20240924-1. Amakusa Regional Medical Center Hospital Ethics Committee; Ethics Committee Chair; Reception number: 20240924-1; Approval number: 20240924-1; Examination items: Appropriateness of conducting clinical research; Examination category: Committee Review (2024/9/24); Review result: Approved. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Kitamura et al.)

In this study, we report a case in which molecular-targeted agents have been shown to be effective in the treatment of unresectable hepatocellular carcinoma(HCC), which has enabled a radical treatment, conversion therapy, and long-term survival with multimodality treatment including RFA. Case: A 61-year-old male, abdominal ultrasonography revealed a large liver tumor and multiple lesions mainly in the right lobe of the liver. He was diagnosed as having unresectable HCC, and treatment with sorafenib was initiated. After treatment, the tumor was clearly reduced in size and the lung metastases disappeared. Five years later, recurrence was observed at the treated site of S7/8, and RFA was performed again after TACE. The patient has survived for 8 years without recurrence.

Statins are cholesterol-lowering agents that act as inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzymeA (HMG CoA) reductase. Recently, statins have received a lot of attention, especially regarding how statins act on the immune system. Here, the clinical impact of statin intake was examined in patients with resected pancreatic cancer, and the underlying mechanisms were investigated in vitro and in vivo . We found that statin intake was associated with favorable prognostic outcomes in patients with resectable pancreatic cancer. Statins, especially lipophilic statins, exert anti-proliferative effects on pancreatic cancer cells in vitro (simvastatin > fluvastatin > atorvastatin > rosuvastatin > pravastatin). Simvastatin had an anti-proliferative effect on pancreatic cancer cells with decreased the yes-associated protein (YAP)/PDZ-binding motif (TAZ) expression by activating the JNK pathway, and simvastatin treatment with oxaliplatin revealed additive anti-growth effects. Furthermore, lipophilic and hydrophilic statins suppressed programmed cell death ligand 1 (PD-L1) expression by downregulating TAZ. Simvastatin treatment with an anti-PD-1 drug (BP0273) provided immediate anti-growth effects compared to controls, such as anti-PD-1 only and simvastatin only, and suppressed progressive disease during the early period of anti-PD-1 treatment in vivo . In conclusion, Statins display two distinct anti-cancer effects (direct anti-growth effect and elimination of immune suppression by downregulating PD-L1 expression) by targeting YAP/TAZ expression., Competing Interests: None., (AJCR Copyright © 2023.)

American Association of Physicists in Medicine (AAPM) Report No.204 recommends the size-specific dose estimates (SSDE), wherein SSDE=computed tomography dose index-volume (CTDIvol )×size correction factor (SCF), as an index of the CT dose to consider patient thickness. However, the study on SSDE has not been made yet for area detector CT (ADCT) device such as a 320-row CT scanner. The purpose of this study was to evaluate the SCF values for ADCT by means of a simulation technique to look into the differences in SCF values due to beam width. In the simulation, to construct the geometry of the Aquilion ONE X-ray CT system (120 kV), the dose ratio and the effective energies were measured in the cone angle and fan angle directions, and these were incorporated into the simulation code, Electron Gamma Shower Ver.5 (EGS5). By changing the thickness of a PMMA phantom from 8 cm to 40 cm, CTDIvol and SCF were determined. The SCF values for the beam widths in conventional and volume scans were calculated. The differences among the SCF values of conventional, volume scans, and AAPM were up to 23.0%. However, when SCF values were normalized in a phantom of 16 cm diameter, the error tended to decrease for the cases of thin body thickness, such as those of children. It was concluded that even if beam width and device are different, the SCF values recommended by AAPM are useful in clinical situations.