Predicting Overall Survival in Patients with Metastatic Rectal Cancer: a Machine Learning Approach.

BackgroundA significant proportion of patients with rectal cancer will present with synchronous metastasis at the time of diagnosis. Overall survival (OS) for these patients are highly variable and previous attempts to build predictive models often have low predictive power, with concordance indexes (c-index) less than 0.70.MethodsUsing the National Cancer Database (2010-2014), we identified patients with synchronous metastatic rectal cancer. The data was split into a training dataset (diagnosis years 2010-2012), which was used to build the machine learning model, and a testing dataset (diagnosis years 2013-2014), which was used to externally validate the model. A nomogram predicting 3-year OS was created using Cox proportional hazard regression with lasso penalization. Predictors were selected based on clinical significance and availability in NCDB. Performance of the machine learning model was assessed by c-index.ResultsA total of 4098 and 3107 patients were used to construct and validate the nomogram, respectively. Internally validated c-indexes at 1, 2, and 3 years were 0.816 (95% CI 0.813-0.818), 0.789 (95% CI 0.786-0.790), and 0.778 (95% CI 0.775-0.780), respectively. External validated c-indexes at 1, 2, and 3 years were 0.811, 0.779, and 0.778, respectively.ConclusionsThere is wide variability in the OS for patients with metastatic rectal cancer, making accurate predictions difficult. However, using machine learning techniques, more accurate models can be built. This will aid patients and clinicians in setting expectations and making clinical decisions in this group of challenging patients

Using machine learning to construct nomograms for patients with metastatic colon cancer

AIM: Patients with synchronous colon cancer metastases have highly variable overall survival (OS), making accurate predictive models challenging to build. We aim to use machine learning to more accurately predict OS in these patients and to present this predictive model in the form of nomograms for patients and clinicians. METHODS: Using the National Cancer Database (2010-2014), we identified right colon (RC) and left colon (LC) cancer patients with synchronous metastases. Each primary site was split into training and testing datasets. Nomograms predicting 3-year overall survival were created for each site using Cox proportional hazard regression with lasso regression. Each model was evaluated by both calibration (comparison of predicted versus observed overall survival) and validation (degree of concordance as measured by c-index) methodologies. RESULTS: A total of 11,018 RC and 8,346 LC patients were used to construct and validate the nomograms. After stratifying each model into 5 risk groups, the predicted OS was within the 95% CI of the observed OS in 4 out of 5 risk groups for both the RC and LC models. Externally validated c-indexes at 3 years for RC and LC models were 0.794 and 0.761, respectively. CONCLUSIONS: Utilization of machine learning can result in more accurate predictive models for patients with metastatic colon cancer. Nomograms built from these models can assist clinicians and patients in the shared decision-making process of their cancer care

Robotic left-stapled total intracorporeal bowel anastomosis versus stapled partial extracorporeal anastomosis: operative technical description and outcomes.

BackgroundAlthough there is extensive literature on robotic total intracorporeal anastomosis (TICA) for right colon resection, left total ICA using the da Vinci Xi robotic platform has only been described in short case series previously. In this study, we report on the largest cohort of robotic left total ICA, provide a description of our institution's techniques, and compare outcomes to robotic left partial extracorporeal anastomosis (PECA).MethodsPatients who underwent robotic left colectomy for any underlying pathology from July 1, 2016 through April 30, 2020 were identified by procedure code. A technical description is provided for two unique techniques performed at our institution. Outcomes included operative time, length of stay, supply cost, post-operative ileus, post-operative morbidity and mortality and need for complete mobilization of the splenic flexure.ResultsFrom a review of our institution's data, 83 robotic TICA cases were identified and 76 robotic PECA cases were identified. Common procedures included low anterior resection, sigmoidectomy, left hemicolectomy, and rectopexy with resection. TICA was associated with significantly shorter intraoperative time compared to PECA.ConclusionsOur series shows that TICA is a safe and feasible technique that does not increase the risk of adverse outcomes. Using either the anvil-forward or anvil-backward technique, we were able to reliably reproduce this method in a total of 83 patients undergoing left colon resection for either benign or malignant diseases

Effects of a Surgical Receipt Program on the Supply Costs of Five General Surgery Procedures.

BACKGROUND:Surgical supplies occupy a large portion of health care expenditures but is often under the surgeon's control. We sought to assess whether an automated, surgeon-directed, cost feedback system can decrease supply expenditures for five common general surgery procedures. MATERIALS AND METHODS:An automated "surgical receipt" detailing intraoperative supply costs was generated and emailed to surgeons after each case. We compared the median cost per case for 18 mo before and after implementation of the surgical receipt. We controlled for price fluctuations by applying common per-unit prices in both periods. We also compared the incision time, case length booking accuracy, length of stay, and postoperative occurrences. RESULTS:Median costs decreased significantly for open inguinal hernia ($433.45 to$385.49, P < 0.001), laparoscopic cholecystectomy ($886.77 to$816.13, P = 0.002), and thyroidectomy ($861.21 to$825.90, P = 0.034). Median costs were unchanged for laparoscopic appendectomy and increased significantly for lumpectomy ($325.67 to$420.53, P < 0.001). There was an increase in incision-to-closure minutes for open inguinal hernia (71 to 75 min, P < 0.001) and laparoscopic cholecystectomy (75 to 96 min, P < 0.001), but a decrease in thyroidectomy (79 to 73 min, P < 0.001). There was an increase in booking accuracy for laparoscopic appendectomy (38.6% to 55.0%, P = 0.001) and thyroidectomy (32.5% to 48.1%, P = 0.001). There were no differences in postoperative occurrence rates and length of stay duration. CONCLUSIONS:An automated surgeon-directed surgical receipt may be a useful tool to decrease supply costs for certain procedures. However, curtailing surgical supply costs with surgeon-directed cost feedback alone is challenging and a multimodal approach may be necessary

Synchronous metastatic colon cancer and the importance of primary tumor laterality - A National Cancer Database analysis of right- versus left-sided colon cancer.

BackgroundThe role of laterality for patients with synchronous metastatic colon cancer (SMCC) is not well-defined.MethodsUsing the National Cancer Database (2010-2015), we compared patients with metastatic right- (RCC) versus left-sided colon cancer (LCC). We performed Kaplan-Meier analysis to compare overall survival (OS) for each metastatic site and utilized adjusted Cox proportional hazard analysis to identify predictors of OS.ResultsPatients with RCCs were more likely to be older, female, and have more comorbidities. LCCs were more likely to metastasize to liver and lung, whereas RCCs were more likely to metastasize to peritoneum and brain. There was equal likelihood to metastasize to bone. OS was significantly longer for LCCs for all metastatic sites. After controlling for multiple variables, RCC (HR 1.426, p < 0.001) remained an independent predictor of worse OS compared to LCC.ConclusionsLaterality of the primary tumor plays an important role in outcomes for patients with SMCC

Outcomes for a Large Cohort of Patients with Rectal Neuroendocrine Tumors: an Analysis of the National Cancer Database

BackgroundRectal neuroendocrine tumors comprise 20% of neuroendocrine tumors in the alimentary tract, but there is controversy surrounding the optimal management of this disease. The purpose of this study is to better define treatment for patients with rectal neuroendocrine tumors.MethodsUsing the National Cancer Database, we analyzed patients with rectal neuroendocrine tumors between 2004 and 2015. Patients with metastatic disease and missing treatment data were excluded. We examined overall survival stratified by tumor size, treatment type, and presence of positive lymph nodes using Kaplan-Meier analysis with log-rank test. Cox proportional hazard regression model was performed to identify factors associated with overall survival.ResultsIn total, 17,448 patients with rectal neuroendocrine tumors were identified; 16,531 of these patients met inclusion criteria. The majority of patients had tumors ≤ 10 mm (9216 patients, 79.8%), and approximately 90% underwent local excision. The probability of 5-year overall survival was significantly higher for patients with smaller tumors (≤ 10 mm: 94.1% 11-20 mm: 85.7%, > 20 mm: 71.8%; p < 0.001) and those with no positive lymph nodes (91.4% versus 53.3%, p < 0.001). The probability of 5-year overall survival differed based on treatment modality (local excision: 93.6%, radical resection: 79.1%, observation alone: 77.1%; p < 0.001). On multivariable Cox regression, when compared to local excision, radical resection was not associated with a difference in overall survival but observation alone was associated with significantly worse OS (HR = 2.750, p < 0.001).ConclusionsThere is a significant difference in overall survival between patients who underwent local excision versus observation alone. Excision of the tumor should be offered to all patients with rectal neuroendocrine tumors who are appropriate surgical candidates, regardless of the tumor size

Multiquadrant surgery in the robotic era: a technical description and outcomes for da Vinci Xi robotic subtotal colectomy and total proctocolectomy

BackgroundCommon colorectal procedures that require access to all quadrants of the abdomen are subtotal colectomy (STC) and total proctocolectomy (TPC). These are frequently performed with a surgical robot, but multiquadrant operations have unique challenges during robot-assisted surgery.MethodsPatients who underwent robotic STC or TPC with the da Vinci Xi surgical robot at our institution from July 1, 2016 through June 30, 2019 were identified by diagnosis and procedure codes. A technical description is provided for the techniques utilized at our institution. Outcomes included operative times (OT), supply cost and length of stay. Associated morbidity and mortality was also analyzed.ResultsFrom a review of our institution's robotic surgery data, 37 cases were identified that utilized the described technique. Of these cases, 21 were robotic STC and 16 were TPC. Total mean OT was 276.86 min (SD ± 119.49). Mean OT was further analyzed by year, which demonstrated an overall decrease in OT from 350.91 min (SD ± 46.38) in 2016 to 221.43 min (SD ± 16.46) in 2018 (p = 0.008). A total of 21 cases were performed prior to 2018. Overall OT for STC was 222.81 min (SD ± 14.54) compared to overall TPC OT 347.81 min (SD ± 34.35). Median length of stay was 5 days [25th and 75th percentiles 4, 6, respectively]. There was no 30-day mortality and only one return to operating room for mesenteric bleeding. There was a low risk of mortality associated with this technique.ConclusionsThe current study provides the largest cohort of patients assessed who have undergone multiquadrant robotic STC or TPC. The study provides a detailed description of the technique utilized at our institution. There was no associated 30-day mortality and a low risk of morbidity. The data suggest that the learning curve for improved operative time is between 15 and 20 cases

Surgeon Awareness of the Relative Costs of Common Surgical Instruments.

This study surveys surgeons’ cost knowledge and ability to distinguish subtle price variations between surgical tools with similar functions or indications

General surgery training in the era of robotic surgery: a qualitative analysis of perceptions from resident and attending surgeons

BackgroundThe use of the surgical robot has increased annually since its introduction, especially in general surgery. Despite the tremendous increase in utilization, there are currently no validated curricula to train residents in robotic surgery, and the effects of robotic surgery on general surgery residency training are not well defined. In this study, we aim to explore the perceptions of resident and attending surgeons toward robotic surgery education in general surgery residency training.MethodsWe performed a qualitative thematic analysis of in-person, one-on-one, semi-structured interviews with general surgery residents and attending surgeons at a large academic health system. Convenient and purposeful sampling was performed in order to ensure diverse demographics, experiences, and opinions were represented. Data were analyzed continuously, and interviews were conducted until thematic saturation was reached, which occurred after 20 residents and seven attendings.ResultsAll interviewees agreed that dual consoles are necessary to maximize the teaching potential of the robotic platform, and the importance of simulation and simulators in robotic surgery education is paramount. However, further work to ensure proper access to simulation resources for residents is necessary. While most recognize that bedside-assist skills are essential, most think its educational value plateaus quickly. Lastly, residents believe that earlier exposure to robotic surgery is necessary and that almost every case has a portion that is level-appropriate for residents to perform on the robot.ConclusionsAs robotic surgery transitions from novelty to ubiquity, the importance of effective general surgery robotic surgery training during residency is paramount. Through in-depth interviews, this study provides examples of effective educational tools and techniques, highlights the importance of simulation, and explores opinions regarding the role of the resident in robotic surgery education. We hope the insights gained from this study can be used to develop and/or refine robotic surgery curricula

Making the Jump: A Qualitative Analysis on the Transition From Bedside Assistant to Console Surgeon in Robotic Surgery Training

ObjectiveTo determine barriers associated with the transition from bedside assistant to console surgeon for general surgery residents in the era of robotic surgery in general surgery training.DesignQualitative thematic analysis using one-on-one interviews of general surgery residents and attendings conducted between June 2018 and February 2019.SettingAn urban, academic, multihospital general surgery residency program with a robust robotic surgery program.ParticipantsConvenient and purposeful sampling was performed to ensure a variety of resident graduate-years and attending subspecialties were represented. Sample size was determined by data saturation, which occurred after 20 resident and 7 attending interviews.ResultsResidents identified the low volume of general surgery robotic cases, the infrequency of exposure to robotic surgery, and attending comfort with robotic surgery (and with teaching on the robot) as potential barriers in the transition from bedside assistant to console surgeon. Residents had to find a replacement bedside assistant in order to be the console surgeon, which was challenging. In addition, residents felt that the current culture surrounding robotic surgery is very hierarchal, limiting their exposure. Attendings' trust in the residents' console skills was a major determining factor in allowing residents on the console.ConclusionsMost robotic surgery education curricula are sequential, requiring the resident to progress from bedside assistant to console surgeon. Unfortunately, there are many potential barriers for residents in the transition from bedside assistant to console surgeon. Some barriers apply to general surgery training overall, but are amplified in robotic surgery, while others are unique to robotic surgery education. Recognition of, and rectifying, these barriers may increase resident participation as the console surgeon