Enhancing Preoperative Outcome Prediction: A Comparative Retrospective Case-Control Study on Machine Learning versus the International Esodata Study Group Risk Model for Predicting 90-Day Mortality in Oncologic Esophagectomy.

Risk prediction prior to oncologic esophagectomy is crucial for assisting surgeons and patients in their joint informed decision making. Recently, a new risk prediction model for 90-day mortality after esophagectomy using the International Esodata Study Group (IESG) database was proposed, allowing for the preoperative assignment of patients into different risk categories. However, given the non-linear dependencies between patient- and tumor-related risk factors contributing to cumulative surgical risk, machine learning (ML) may evolve as a novel and more integrated approach for mortality prediction. We evaluated the IESG risk model and compared its performance to ML models. Multiple classifiers were trained and validated on 552 patients from two independent centers undergoing oncologic esophagectomies. The discrimination performance of each model was assessed utilizing the area under the receiver operating characteristics curve (AUROC), the area under the precision-recall curve (AUPRC), and the Matthews correlation coefficient (MCC). The 90-day mortality rate was 5.8%. We found that IESG categorization allowed for adequate group-based risk prediction. However, ML models provided better discrimination performance, reaching superior AUROCs (0.64 [0.63-0.65] vs. 0.44 [0.32-0.56]), AUPRCs (0.25 [0.24-0.27] vs. 0.11 [0.05-0.21]), and MCCs (0.27 ([0.25-0.28] vs. 0.15 [0.03-0.27]). Conclusively, ML shows promising potential to identify patients at risk prior to surgery, surpassing conventional statistics. Still, larger datasets are needed to achieve higher discrimination performances for large-scale clinical implementation in the future.

Robotic-Assisted Ivor Lewis Esophagectomy Is Safe and Cost Equivalent Compared to Minimally Invasive Esophagectomy in a Tertiary Referral Center.

In recent decades, robotic-assisted minimally invasive esophagectomy (RAMIE) has been increasingly adopted for patients with esophageal cancer (EC) or cancer of the gastroesophageal junction (GEJ). However, concerns regarding its costs compared to conventional minimally invasive esophagectomy (MIE) have emerged. This study examined outcomes and costs of RAMIE versus total MIE in 128 patients who underwent Ivor Lewis esophagectomy for EC/GEJ at our department between 2017 and 2021. Surgical costs were higher for RAMIE (EUR 12,370 vs. EUR 10,059, p < 0.001). Yet, median daily (EUR 2023 vs. EUR 1818, p = 0.246) and total costs (EUR 30,510 vs. EUR 29,180, p = 0.460) were comparable. RAMIE showed a lower incidence of postoperative pneumonia (8% vs. 25%, p = 0.029) and a trend towards shorter hospital stays (15 vs. 17 days, p = 0.205), which may have equalized total costs. Factors independently associated with higher costs included readmission to the intensive care unit (hazard ratio [HR] = 7.0), length of stay (HR = 13.5), anastomotic leak (HR = 17.0), and postoperative pneumonia (HR = 5.4). In conclusion, RAMIE does not impose an additional financial burden. This suggests that RAMIE may be considered as a valid alternative approach for esophagectomy. Attention to typical cost factors can enhance postoperative care across surgical methods.

Reducing the Pill Burden: Immunosuppressant Adherence and Safety after Conversion from a Twice-Daily (IR-Tac) to a Novel Once-Daily (LCP-Tac) Tacrolimus Formulation in 161 Liver Transplant Patients.

Non-adherence to immunosuppressant therapy reduces long-term graft and patient survival after solid organ transplantation. The objective of this 24-month prospective study was to determine adherence, efficacy and safety after conversion of stable liver transplant (LT) recipients from a standard twice-daily immediate release Tacrolimus (IR-Tac) to a novel once-daily life cycle pharma Tacrolimus (LCP-Tac) formulation. We converted a total of 161 LT patients at baseline, collecting Tacrolimus trough levels, laboratories, physical examination data and the BAASIS© questionnaire for self-reported adherence to immunosuppression at regular intervals. With 134 participants completing the study period (17% dropouts), the overall adherence to the BAASIS© increased by 57% until month 24 compared to baseline (51% vs. 80%). Patients who required only a morning dose of their concomitant medications reported the largest improvement in adherence after conversion. The intra-patient variability (IPV) of consecutive Tacrolimus trough levels after conversion did not change significantly compared to pre-conversion levels. Despite reducing the daily dose by 30% at baseline as recommended by the manufacturer, Tac-trough levels remained stable, reflected by an increase in the concentration-dose (C/D) ratio. No episodes of graft rejection or loss occurred. Our data suggest that the use of LCP-Tac in liver transplant patients is safe and can increase adherence to immunosuppression compared to conventional IR-Tac.

Perioperative Risk Assessment in Pancreatic Surgery Using Machine Learning.

Pancreatic surgery is associated with a high risk for postoperative complications and death of patients. Complications occur in a variable interval after the procedure. Often, a patient has already left the ICU and is not properly monitored anymore when the complication occurs. Risk stratification models can assist in identifying patients at risk in order to keep these patients in ICU for longer. This, in turn, helps to identify complications earlier and increase survival rates. We trained multiple machine learning models on pre-, intra- and short term postoperative data from patients who underwent pancreatic resection at the Department of Surgery, Campus Charité Mitte | Campus Virchow-Klinikum, Charité - Universitätsmedizin Berlin. The presented models achieve an area under the precision-recall curve (AUPRC) of up to 0.51 for predicting patient death and 0.53 for predicting a specific major complication. Overall, we found that a classical logistic regression model performs best for the investigated classification tasks. As more patient data becomes available throughout the perioperative stay, the performance of the risk stratification model improves and should therefore repeatedly be computed.

Intrahepatic De Novo Tumors in Liver Recipients are Highly Associated With Recurrent Viral Hepatitis.

BACKGROUND/AIMS: Long-term survival of liver transplant recipients is endangered by tumorigenesis at different sites. Little is known about primary de novo tumors developing in the graft. METHODS: We analyzed the follow-up data of 2731 liver recipients that were transplanted between 1988 and 2019 at our institution (Charité - Universitätsmedizin Berlin, Department of Surgery). All cases with new intrahepatic tumors during follow-up were identified. RESULTS: A total of nine patients were diagnosed at a median of 16 years (range, 2-24 years) after surgery. Eight patients presented with hepatocellular carcinoma (HCC), and one patient presented with epithelioid hemangioendothelioma (EHE). All eight HCC patients had a recurrence of the initial disease that had caused liver failure before transplantation. This was associated with viral reinfection with either HCV or HBV in seven cases. Of the nine patients, three underwent surgical resection and only one patient was alive at data abstraction. CONCLUSION: Intrahepatic de novo neoplasms in the liver graft need to be considered in the long-term follow-up of liver recipients and were strongly associated with recurrent viral hepatitis in our study. Although prognosis of this rare complication is generally poor, patients may benefit from surgical resection of localized disease.

Evaluation of histological dynamics, kidney function and diabetes in liver transplant patients after antiviral treatment with direct-acting antivirals: Therapy of HCV-recurrence.

BACKGROUND: Direct-acting antivirals allow efficient and safe treatment of hepatitis C (HCV) before and after liver transplantation (LT). However, the impact of sofosbuvir on the graft, diabetes, and on kidney function is not answered yet. Primary endpoint of this analysis was the evaluation of kidney function after antiviral treatment (AVT). Secondary endpoints were the assessment of extrahepatic manifestation of HCV-infection by diabetes mellitus and the histopathological changes in terms of inflammation, content of fat, and fibrosis stage. METHODS: From 2014 to 4/2015, 100 patients with HCV-recurrence after LT were successfully treated with AVT. Ninety-eight received a sofosbuvir-based regimen. Indication was based on genotype, transplant fibrosis stage, and urgency. Biopsies were evaluated before and after treatment. Renal function and diabetes were assessed before, during, and after AVT. RESULTS: All patients achieved sustained virological response. A significant improvement of inflammation (P = 0.001) and fibrosis stage (P = 0.031) were observed. Significantly less insulin was required in 32 patients with diabetes (P < 0.001) to keep Hb1Ac unchanged after AVT. Kidney function was stable during, 12 weeks after and 48 weeks after antiviral therapy. Stages of renal insufficiency were comparable before and after AVT. CONCLUSION: Successful sofosbuvir-based AVT leads to a variety of positive development in transplant patients including a significant improvement of inflammation, fat content and fibrosis, a significant decrease in daily insulin dose and no significant impairment of kidney function.