Methods for improving colorectal cancer annotation efficiency for artificial intelligence-observer training.

BACKGROUND: Missing occult cancer lesions accounts for the most diagnostic errors in retrospective radiology reviews as early cancer can be small or subtle, making the lesions difficult to detect. Second-observer is the most effective technique for reducing these events and can be economically implemented with the advent of artificial intelligence (AI). AIM: To achieve appropriate AI model training, a large annotated dataset is necessary to train the AI models. Our goal in this research is to compare two methods for decreasing the annotation time to establish ground truth: Skip-slice annotation and AI-initiated annotation. METHODS: We developed a 2D U-Net as an AI second observer for detecting colorectal cancer (CRC) and an ensemble of 5 differently initiated 2D U-Net for ensemble technique. Each model was trained with 51 cases of annotated CRC computed tomography of the abdomen and pelvis, tested with 7 cases, and validated with 20 cases from The Cancer Imaging Archive cases. The sensitivity, false positives per case, and estimated Dice coefficient were obtained for each method of training. We compared the two methods of annotations and the time reduction associated with the technique. The time differences were tested using Friedman's two-way analysis of variance. RESULTS: Sparse annotation significantly reduces the time for annotation particularly skipping 2 slices at a time (P < 0.001). Reduction of up to 2/3 of the annotation does not reduce AI model sensitivity or false positives per case. Although initializing human annotation with AI reduces the annotation time, the reduction is minimal, even when using an ensemble AI to decrease false positives. CONCLUSION: Our data support the sparse annotation technique as an efficient technique for reducing the time needed to establish the ground truth.

Shifting Paradigms in the Pathophysiology and Treatment of Carcinoid Crisis.

Carcinoid crisis is a potentially fatal condition characterized by various symptoms, including hemodynamic instability, flushing, and diarrhea. The incidence of carcinoid crisis is unknown, in part due to inconsistency in definitions across studies. Triggers of carcinoid crisis include general anesthesia and surgical procedures, but drug-induced and spontaneous cases have also been reported. Patients with neuroendocrine tumors (NETs) and carcinoid syndrome are at risk for carcinoid crisis. The pathophysiology of carcinoid crisis has been attributed to secretion of bioactive substances, such as serotonin, histamine, bradykinin, and kallikrein by NETs. The somatostatin analog octreotide has been considered the standard of care for carcinoid crisis due to its inhibitory effect on hormone release and relatively fast resolution of carcinoid crisis symptoms in several case studies. However, octreotide's efficacy in the treatment of carcinoid crisis has been questioned. This is due to a lack of a common definition for carcinoid crisis, the heterogeneity in clinical presentation, the paucity of prospective studies assessing octreotide efficacy in carcinoid crisis, and the lack of understanding of the pathophysiology of carcinoid crisis. These issues challenge the classical physiologic model of carcinoid crisis and its common etiology with carcinoid syndrome and raise questions regarding the utility of somatostatin analogs in its treatment. As surgical procedures and invasive liver-directed therapies remain important treatment modalities in patients with NETs, the pathophysiology of carcinoid crisis, potential benefits of octreotide, and efficacy of alternative treatment modalities must be studied prospectively to develop an effective evidence-based treatment strategy for carcinoid crisis.

Recurrence Patterns After Surgical Resection of Gastroenteropancreatic Neuroendocrine Tumors: Analysis From the National Comprehensive Cancer Network Oncology Outcomes Database.

OBJECTIVE: Current National Comprehensive Cancer Network guidelines for gastroenteropancreatic neuroendocrine tumors (GEPNETs) recommend complete (R0) surgical resection of the primary tumor and metastases, if feasible. However, large multicenter studies of recurrence patterns of GEPNETs after resection have not been performed. METHODS: Patients 18 years or older who presented to 7 participating National Comprehensive Cancer Network institutions between 2004 and 2008 with a new diagnosis of a small bowel, pancreas, or colon/rectum neuroendocrine tumor (NET) and underwent R0 resection of the primary tumor, and synchronous metastases, if present, were included in this analysis. Descriptive statistics and Kaplan-Meier estimates were used to calculate recurrence rates and time-associated end points, respectively. RESULTS: Of 294 patients with GEPNETs, 50% were male, 88% were White, and 99% had Eastern Cooperative Oncology Group performance status 0 to 1. The median age was 55 years (range, 20-90). The median follow-up time from R0 resection was 62.1 months. Recurrence rates were 18% in small bowel NETs (n = 110), 26% in pancreatic NETs (n = 141), and 10% in colon/rectum NETs (n = 50). The frequency of surveillance imaging was highly variable. CONCLUSIONS: R0 resection was associated with variable risk of recurrence across subtypes. Further research to inform refinement of guidelines for the appropriate duration of surveillance after R0 resection is needed.

Tumor Biology Impacts Survival in Surgically Managed Primary Hepatic Vascular Malignancies.

BACKGROUND: Hepatic angiosarcoma (AS) and hepatic epithelioid hemangioendothelioma (HEHE) are rare primary hepatic vascular malignancies (PHVM) that remain poorly understood. To guide management, we sought to identify factors and trends predicting survival after surgical intervention using a national database. MATERIALS AND METHODS: In a retrospective analysis of the National Cancer Database patients with a diagnosis of PHVM were identified. Clinicopathologic factors were extracted and compared. Overall survival (OS) was estimated and predictors of survival were identified. RESULTS: Three hundred ninty patients with AS and 216 with HEHE were identified. Only 16% of AS and 36% of HEHE patients underwent surgery. The median OS for patients who underwent surgical intervention was 97 months, with 5-year OS of 30% for AS versus 69% for HEHE patients (P< 0.001). Tumor biology strongly impacted OS, with AS histology (Hazard Ratio [HR] of 3.61 [1.55-8.42]), moderate/poor tumor differentiation (HR = 3.86 [1.03-14.46]) and tumor size (HR = 1.01 [1.00-1.01]) conferring worse prognosis. The presence of metastatic disease in the surgically managed cohort (HR = 5.22 [2.01-13.57]) and involved surgical margins (HR = 3.87 [1.59-9.42]), were independently associated with worse survival. CONCLUSIONS: In this national cohort of PHVM, tumor biology, in the form of angiosarcoma histology, tumor differentiation and tumor size, was strongly associated with worse survival after surgery. Additionally, residual tumor burden after resection, in the form of positive surgical margins or the presence of metastasis, was also negatively associated with survival. Long-term clinical outcomes remain poor for patients with the above high-risk features, emphasizing the need to develop effective forms of adjuvant systemic therapies for this group of malignancies.

Guidelines for Management of Urgent Symptoms in Patients with Cholangiocarcinoma and Biliary Stents or Catheters using the Modified RAND/UCLA Delphi Process.

Background: Patients with cholangiocarcinoma often have indwelling biliary stents or catheters which are prone to obstructions and/or infections; studies show that 20-40% present with fever and/or jaundice requiring urgent treatment in the outpatient setting for which there are no uniform guidelines. The goal was to develop an expert panel consensus on this topic using the modified RAND/UCLA Delphi process to rate treatment appropriateness. Methods: Thirteen expert physicians from relevant specialties, geography, and practice settings were recruited for the panel. Patient scenarios were developed and panelists rated the therapies before and after a face-to-face discussion. The appropriateness of various therapies was rated on a scale from 1-9 and classified as appropriate, inappropriate, or uncertain. Scenarios with greater than 2 (>2) ratings of 1-3 (inappropriate) and greater than 2 (>2) ratings of 7-9 (appropriate) were considered to have disagreement and were not assigned an appropriateness rating. Results: Panelists were from all US regions and the UK (8%) and had practiced for a mean 16.5 years (4-33 years). Panelists rated 480 scenarios before the meeting and re-rated 288 of the clinical scenarios after the meeting. The panelists agreed that ongoing treatment with chemotherapy did not influence decision-making and, therefore, 192 scenarios were excluded from the final list. Disagreement decreased from 37.5% before to 10.4% after the meeting. Consensus on stent/tube manipulation and inpatient antibiotic therapy was obtained and summarized in patients as "appropriate" or "maybe appropriate" based on a patient's bilirubin level at presentation. Conclusions: The Delphi process produced consensus guidelines to fill an unmet need in the urgent management of ascending cholangitis in patients with cholangiocarcinoma.

The effect of gender on operative autonomy in general surgery residents.

BACKGROUND: Despite an increasing number of women in the field of surgery, bias regarding cognitive or technical ability may continue to affect the experience of female trainees differently than their male counterparts. This study examines the differences in the degree of operative autonomy given to female compared with male general surgery trainees. METHODS: A smartphone app was used to collect evaluations of operative autonomy measured using the 4-point Zwisch scale, which describes defined steps in the progression from novice ("show and tell") to autonomous surgeon ("supervision only"). Differences in autonomy between male and female residents were compared using hierarchical logistic regression analysis. RESULTS: A total of 412 residents and 524 faculty from 14 general surgery training programs evaluated 8,900 cases over a 9-month period. Female residents received less autonomy from faculty than did male residents overall (P < .001). Resident level of training and case complexity were the strongest predictors of autonomy. Even after controlling for potential confounding factors, including level of training, intrinsic procedural difficulty, patient-related case complexity, faculty sex, and training program environment, female residents still received less operative autonomy than their male counterparts. The greatest discrepancy was in the fourth year of training. CONCLUSION: There is a sex-based difference in the autonomy granted to general surgery trainees. This gender gap may affect female residents' experience in training and possibly their preparation for practice. Strategies need to be developed to help faculty and residents work together to overcome this gender gap.

Neuroendocrine Tumors in Meckel's Diverticulum: Recommendation for Lymphadenectomy Regardless of Tumor Size Based on the NCDB Experience.

BACKGROUND: Meckel's diverticulum (MD) is an anomaly of the small intestine from which malignancy may arise. Among MD neoplasms, neuroendocrine tumors (NETs) are considered the most common. However, their metastatic potential and optimal surgical therapy remain ill-defined. METHODS: In a retrospective analysis of the National Cancer Database (2004-2015), patients with a diagnosis of MD malignancy were identified. Clinicopathologic factors were extracted and tumors arising in MD were compared. In the subgroup of patients with NET, the association between tumor factors and node involvement was investigated. RESULTS: Three hundred twenty primary MD malignancies were captured in the National Cancer Database, consisting of 280 (87.5%) NET. The median age at diagnosis was 64 years. Patients were predominantly male (207, 73.9%) and white (269, 96.1%). Most tumors were well-differentiated (118, 42.1%) and sub-centimeter (median size, 0.7 cm). Distant metastasis was present in a minority (16, 5.7%), and the median overall survival was 114 months in the entire cohort. The regional lymph node status was known in 87 NET patients, out of which 39 (44.8%) harbored node metastasis. Although the risk of node involvement increased with larger tumor size, it remained significant even among sub-centimeter (9 out of 34, 26.5%) and well-differentiated (18 out of 44, 41%) tumors. Regional node involvement was associated with the presence of distant metastasis (p < 0.001). CONCLUSION: Lymph node involvement was common irrespective of the size and grade of NET arising from Meckel's diverticulum. Therefore, regional lymphadenectomy should be considered in the curative-intent surgical management of these neoplasms regardless of tumor size and grade.

Non-home Discharge and Prolonged Length of Stay After Cytoreductive Surgery and HIPEC.

BACKGROUND: Predictive models for nonhome discharge (NHD) have been proposed in major surgical specialties. The rates and risk factors associated with NHD and prolonged length of stay (PLOS) after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) have not been evaluated. The aim of this study is to identify risk factors for NHD and PLOS after CRS/HIPEC in a national cohort of patients. MATERIALS AND METHODS: CRS/HIPEC cases were identified from the National Surgical Quality Improvement Program 2011-2012 data set. Patients with an NHD or PLOS (>30 d) were compared with a group of patients discharged to home within 30 d. Univariate analysis was used to compare patient characteristics, operative variables, and postoperative complications among both groups. Multivariate regression analysis was used to identify independent predictors of NHD and PLOS. RESULTS: Five hundred fifty-six patients undergoing CRS/HIPEC were identified, of which 44 (7.9%) were not discharged to home within 30 d. The rate of NHD and PLOS in this cohort was 4.1% and 3.7%, respectively. Multivariate analysis identified age ≥65 y, pre-op albumin <3.0 g/dL, and having a multivisceral resection as independent predictors of NHD/PLOS. If all three predictors are met preoperatively, the probability of NHD/PLOS was calculated to be 30.2%. CONCLUSIONS: The main risk factors for NHD/PLOS after CRS/HIPEC were advanced age, hypoalbuminemia, and multivisceral resection. Adequate identification of these risk factors may facilitate preoperative discussion with patients, and improve discharge planning and resource utilization.

Access to Paid Parental Leave for Academic Surgeons.

BACKGROUND: Parental leave is linked to health benefits for both child and parent. It is unclear whether surgeons at academic centers have access to paid parental leave. The aim of this study was to determine parental leave policies at the top academic medical centers in the United States to identify trends among institutions. METHODS: The top academic medical centers were identified (US News & World Report 2016). Institutional websites were reviewed, or human resource departments were contacted to determine parental leave policies. "Paid leave" was defined as leave without the mandated use of personal time off. Institutions were categorized based on geographical region, funding, and ranking to determine trends regarding availability and duration of paid parental leave. RESULTS: Among the top 91 ranked medical schools, 48 (53%) offer paid parental leave. Availability of a paid leave policy differed based on private versus public institutions (70% versus 38%, P < 0.01) and on medical center ranking (top third = 77%; middle third = 53%; and bottom third = 29%; P < 0.01) but not based on region (P = 0.06). Private institutions were more likely to offer longer paid leaves (>6 wk) than public institutions (67% versus 33%; P = 0.02). No difference in paid leave duration was noted based on region (P = 0.60) or rank (P = 0.81). CONCLUSIONS: Approximately, 50% of top academic medical centers offer paid parental leave. Private institutions are more likely to offer paid leave and leave of longer duration. There is considerable variability in access to paid parenteral leave for academic surgeons.

Comparison of Overall Survival Between Preoperative Chemotherapy and Chemoradiotherapy for Resectable Pancreatic Adenocarcinoma.

Background: Preoperative therapy is being increasingly used in the treatment of resectable pancreatic cancer. Because there are only limited data on the optimal preoperative regimen, we compared overall survival (OS) between preoperative chemotherapy (CT) and preoperative chemoradiotherapy (CRT) in resectable pancreatic adenocarcinoma. Patients and Methods: Patients receiving preoperative therapy and resection for clinical T1-3N0-1M0 adenocarcinoma of the pancreas were identified in the National Cancer Database for 2006 through 2012. We constructed inverse probability of treatment weights to balance baseline group differences, and compared OS between CT and CRT, as well as pathologic and postoperative findings. Results: We identified 1,326 patients (CT: 616; CRT: 710). Differences in OS were not significant between CRT and CT (median survival, 25 vs 26 months; P=.10; weight-adjusted hazard ratio, 0.89; 95% CI, 0.77-1.02). Compared with patients in the CT group, those in the CRT group had lower pathologic T stage (ypT0/T1/T2: 36% vs 21%; P<.01), less lymph node involvement (ypN1: 35% vs 59%; P<.01), and fewer positive resection margins (14% vs 21%; P=.01), but had more postoperative unplanned readmissions (9% vs 6%; P=.01) and increased 90-day mortality (7% vs 4%; P=.03). Those in the CRT group were also less likely to receive postoperative therapy (26% vs 51%; P<.01). Conclusions: Preoperative CT and CRT have similar OS, but CRT is associated with more favorable pathologic features at the cost of higher postoperative morbidity and mortality. Additional trials investigating preoperative therapy are needed for patients with resectable pancreatic cancer.

Neisseria mucosa Peritonitis in the Setting of a Migrated Intrauterine Device.

Peritonitis is a major complication in peritoneal dialysis (PD) patients, often requiring a switch to hemodialysis (HD). Common sources of bacterial peritonitis are touch contamination and PD catheter-related infection. Intra-abdominal pathology is a less common cause of peritonitis in PD patients, and rarely is Neisseria mucosa the causative organism.We present an uncommon case of N. mucosa peritonitis in a 30-year-old African American female patient treated with nocturnal intermittent PD. The infection occurred in the setting of a translocated intrauterine contraceptive device (IUCD) in the infrahepatic region because of transmural migration. Our patient underwent laparoscopic removal of the IUCD and received empiric intraperitoneal (IP) vancomycin and intravenous ceftriaxone. After the isolate was identified as N. mucosa, her regimen was changed to IP ceftriaxone for a total of 21 days. Cell count after completion of antibiotics showed resolution of the peritonitis. The PD catheter was salvaged and transition to HD was avoided.

Improved Survival in Surgically Resected Distal Cholangiocarcinoma Treated with Adjuvant Therapy: a Propensity Score Matched Analysis.

BACKGROUND: Data on the efficacy of adjuvant therapy (AT) in distal cholangiocarcinoma (dCCA) is limited. This study aimed to determine the role of AT in resected dCCA and identify subgroups that benefit from AT. METHODS: We conducted a retrospective review of surgically resected dCCA in the NCDB from 2004 to 2013. Patients who received AT or observation (OB) were matched by propensity score. Log-rank test was used to compare OS. RESULTS: Of 1782 patients with resected dCCA, 840 (47%) were in the OB group and 942 (53%) in the AT group. AT was younger (64.0 vs. 68.7 years, p < 0.001), had less comorbidities (Charlson Deyo score 0) (74.6 vs. 68.0%, p < 0.001), and more likely to have private insurance (p < 0.001). AT was more likely to present with T3/T4 stage (72 vs. 57%, p < 0.001), N1/N2 disease (58 vs. 37%, p < 0.001), and positive surgical margins (26 vs. 16%, p < 0.001). After 1:1 propensity score matching, 500 OB and 500 AT patients were compared. AT was associated with better OS (HR 0.79; 95% CI 0.67-0.93). Median OS was 31 and 25 months for the AT and OB (p = 0.006). The 1-, 3-, and 5-year survival rates were 87, 46, and 31% for AT; 79, 39, and 24% for OB. Subgroup analysis revealed an associated survival advantage for AT in T3/T4 tumors (HR = 0.72; 95% CI 0.59-0.89), node positive disease (HR 0.70; 95% CI 0.56-0.87), and positive margins (HR 0.58; 95% CI 0.42-0.81). CONCLUSION: AT is associated with improved OS in resected dCCA, especially in T3/T4 tumors, node positive disease, and positive margins.

Is the operative autonomy granted to a resident consistent with operative performance quality.

BACKGROUND: We investigated attending surgeon decisions regarding resident operative autonomy, including situations where operative autonomy was discordant with performance quality. METHODS: Attending surgeons assessed operative performance and documented operative autonomy granted to residents from 14 general surgery residency programs. Concordance between performance and autonomy was defined as "practice ready performance/meaningfully autonomous" or "not practice ready/not meaningfully autonomous." Discordant circumstances were practice ready/not meaningfully autonomous or not practice ready/meaningfully autonomous. Resident training level, patient-related case complexity, procedure complexity, and procedure commonality were investigated to determine impact on autonomy. RESULTS: A total of 8,798 assessments were collected from 429 unique surgeons assessing 496 unique residents. Practice-ready and exceptional performances were 20 times more likely to be performed under meaningfully autonomous conditions than were other performances. Meaningful autonomy occurred most often with high-volume, easy and common cases, and less complex procedures. Eighty percent of assessments were concordant (38% practice ready/meaningfully autonomous and 42% not practice ready/not meaningfully autonomous). Most discordant assessments (13.8%) were not practice ready/meaningfully autonomous. For fifth-year residents, practice ready/not meaningfully autonomous ratings (9.7%) were more frequent than not practice ready/meaningfully autonomous ratings (7.5%). Ten surgeons (2.3%) failed to afford residents meaningful autonomy on any occasion. CONCLUSION: Resident operative performance quality is the most important determinant in attending surgeon decisions regarding resident autonomy.

Comparative outcomes of adenosquamous carcinoma of the pancreas: An analysis of the National Cancer Database.

BACKGROUND: A paucity of data exists regarding the natural history and outcome measures of adenosquamous carcinoma of the pancreas (ASCP), a histology distinct from pancreatic adenocarcinoma (PDAC). The aim of this study is to characterize the clinicopathological features of ASCP in a large cohort of patients comparing outcome measures of surgically resected patients to PDAC. METHODS: We identified patients diagnosed with ASCP or PDAC from the National Cancer Database from 2004 to 2012. Patient demographics, tumor characteristics, treatment regimens, and overall survival were analyzed between the groups. RESULTS: We identified 207 073 patients: 205 328 (99%) in the PDAC group and 1745 (1%) in the ASCP group. ASCP tumors were larger, located more frequently in a body/tail location (36% vs 24%, P < 0.001), undifferentiated/anaplastic histology (41% vs 17%, P < 0.001), and early stage presentation, (39% vs 32%, P < 0.001). There was no significant difference in OS when comparing all patients with PDAC and ASCP (6.2 months and 5.7 months, P = 0.601). In surgical patients ASCP histology was associated with worse OS (14.8 months vs 20.5 months, P < 0.001) but had lower nodal involvement (55% vs 61%, P < 0.001). ASCP histology was independently associated with worse OS, after adjusting for tumor characteristics, treatment, and patient demographics. In patients with only resected ASCP histology, negative lymph node status, R0 surgical resection, and receipt of chemotherapy was independently associated with improved overall survival following surgical resection. CONCLUSION: Although patients with ASCP and PDAC tumors have similar survival when non-surgical and surgical patients are combined, ASCP is associated with worse survival in stage I/II resected patients.

Association of Adjuvant Chemotherapy With Overall Survival in Patients With Rectal Cancer and Pathologic Complete Response Following Neoadjuvant Chemotherapy and Resection.

Importance: Adjuvant chemotherapy (AC) in patients with rectal cancer with pathologic complete response following neoadjuvant chemoradiotherapy (nCRT) and resection is recommended by treatment guidelines. However, its role in this setting is equivocal because data supporting benefits are lacking. Objective: To compare the overall survival (OS) between AC and postoperative observation (OB) in patients with rectal cancer with pathologic complete response following nCRT and resection. Design, Setting, and Participants: We identified a cohort of patients with rectal cancer and a complete pathological response (ypT0N0) after nCRT in the National Cancer Database between 2006 and 2012. Patients who received AC were compared with OB patients by propensity score matching. Overall survival was compared using the stratified log-rank test and stratified Cox regression model. The outcomes after AC vs OB were also evaluated in patient subgroups. The data analysis was completed in June 2017. Exposures: Adjuvant chemotherapy and OB. Main Outcomes and Measures: Overall survival. Results: We identified 2764 patients (mean [SD] age, 60.0 [12.3] years; 40% female) with clinical stage II or III resected adenocarcinoma of the rectum who had received nCRT and were complete responders (ypT0N0M0). Of this cohort, 741 patients in the AC group were matched by propensity score to 741 patients who underwent OB. The AC cohort had better OS compared with the OB cohort (hazard ratio, 0.50; 95% CI, 0.32-0.79). The 1-, 3-, and 5-year OS rates were 99.7%, 97.1%, and 94.7% for the AC group and 99.2%, 93.6%, and 88.4% for the OB group (P = .005). In subgroup analysis, patients with clinical stage T3/T4 and node-positive disease benefited most from AC (hazard ratio, 0.47; 95% CI, 0.25-0.91). Conclusions and Relevance: Adjuvant chemotherapy was associated with improved OS in patients with pathologic complete response after nCRT for resected locally advanced rectal cancer. This study supports the use of AC in this setting where there is currently paucity of data.

Adjuvant Therapy Is Associated With Improved Survival in Resected Perihilar Cholangiocarcinoma: A Propensity Matched Study.

BACKGROUND: There are limited well-controlled studies that conclusively demonstrate a benefit of adjuvant therapy in resected perihilar cholangiocarcinoma. Most studies include all biliary tract tumors as one entity despite the heterogeneity of these diseases. METHODS: We identified patients with resected perihilar cholangiocarcinoma from the National Cancer Database between 2006 and 2013. Patients who received adjuvant therapy (AT) were compared to an observation (OB) cohort by propensity score matching. RESULTS: We identified 1846 patients: 1053 patients (57%) in the OB group, and 793 (43%) in the AT group. Patients who received adjuvant therapy were more likely to be younger, have a higher rate of private insurance, have higher T and N stage tumors, and were more likely to have positive resection margins. After 1:1 propensity score matching, 577 OB group patients were compared with 577 AT group patients. The AT cohort was associated with better overall survival compared with the OB cohort (hazard ratio [HR] 0.73; 95% confidence interval [CI] 0.64-0.83). The median survival was 29.5 and 23.3 months for the AT and OB groups, respectively (P < 0.01). Subgroup analysis demonstrated a survival advantage for adjuvant therapy in disease with positive resection margins (HR 0.53; 95% CI 0.42-0.67). CONCLUSIONS: Adjuvant therapy is associated with improved survival in resected perihilar cholangiocarcinoma, especially in disease with positive resection margins. This study supports the use of adjuvant therapy in high-risk patients.

Determining the Adequate Examined Lymph Node Count in Resected Ampullary Adenocarcinoma-A National Cohort Study.

BACKGROUND: The evaluation of lymph node involvement is an essential component of cancer staging. Examining an inadequate number of lymph nodes potentially results in understaging. Current guidelines for lymph node retrieval for ampullary adenocarcinoma are based on data extrapolated from other periampullary malignancies and may not be applicable. The aim of this study was to determine the number of lymph nodes that should be examined in resection specimens to optimize staging in ampullary adenocarcinoma. METHODS: Patients with ampullary adenocarcinoma from 2004 to 2014 were identified in the National Cancer Database. We determined the minimum examined lymph node (ELN) count by modeling each potential ELN count from 2 to 30 in a multivariable regression analysis and confirmed the results with a sensitivity analysis. RESULTS: We identified 7451 patients of whom 52.2% had T3 or T4 disease and 51.4% had lymph node metastases. The median ELN count was 13 (interquartile range, 8-19). Increasing ELNs were independently associated with an increased likelihood of having positive nodal disease (odds ratio, 1.03; 95% confidence interval [CI], 1.03-1.04) and improved overall survival in both node-negative (hazard ratio [HR], 0.98; 95% CI, 0.97-0.99) and node-positive patients (HR, 0.99; 95% CI, 0.986-0.998). We determined that at least 17 lymph nodes should be examined. Overall survival for patients with 17 or more ELNs was superior than for those with fewer than 17 ELNs. CONCLUSION: Increasing ELNs were independently associated with improved overall survival in patients with resected ampullary adenocarcinoma. At least 17 lymph nodes should be examined for optimal nodal staging.

Relationship of procedural numbers with meaningful procedural autonomy in general surgery residents.

BACKGROUND: Concerns exist regarding the competency of general surgery graduates with performing core general surgery procedures. Current competence assessment incorporates minimal procedural numbers requirements. METHODS: Based on the Zwisch scale we evaluated the level of autonomy achieved by categorical PGY1-5 general surgery residents at 14 U.S. general surgery resident training programs between September 1, 2015 and December 31, 2016. With 5 of the most commonly performed core general surgery procedures, we correlated the level of autonomy achieved by each resident with the number of procedures they had performed before the evaluation period, with the intent of identifying specific target numbers that would correlate with the achievement of meaningful autonomy for each procedure with most residents. RESULTS: Whereas a definitive target number was identified for laparoscopic appendectomy (i.e. 25), for the other 4 procedures studied (i.e. laparoscopic cholecystectomy, 52; open inguinal hernia repair, 42; ventral hernia repair, 35; and partial colectomy, 60), target numbers identified were less definitive and/or were higher than many residents will experience during their surgical residency training. CONCLUSIONS: We conclude that procedural target numbers are generally not effective in predicting procedural competence and should not be used as the basis for determining residents' readiness for independent practice.

Robotic-assisted versus laparoscopic pancreaticoduodenectomy: oncological outcomes.

BACKGROUND: Minimally invasive pancreaticoduodenectomy (MIPD) is being performed with increasing frequency for pancreatic cancer, but the most oncologically efficacious surgical platform, whether robotic or laparoscopic, is yet to be determined. Currently, there are no national studies comparing the oncological outcomes between robotic (RPD) and laparoscopic (LPD) pancreaticoduodenectomy. METHODS: This was a retrospective study using the National Cancer Database between 2010 and 2013. We compared the perioperative, pathological, and mid-term oncological outcomes between RPD and LPD. RESULTS: There were 1623 MIPD cases, of which 90% were LPD and 10% were RPD. Most LPD (63%) and RPD (51%) cases were performed at institutions with a volume of ≤ 5 MIPDs per year. There were no differences in patient- and tumor-related factors between the groups. The majority of treated tumors were adenocarcinoma (90.1% for RPD and 89.1% for LPD). RPDs were more likely to be performed at academic centers (89.1%) compared to LPDs (68.1%, P < 0.001) and at higher-volume centers (median MIPD/year of 4.7 for RPD vs 3.6 for LPD, P < 0.001). There was no difference in the median number of examined lymph nodes, margin status, median length of stay, 90-day mortality, or 30-day readmission between groups. There was no difference in median overall survival for pancreatic adenocarcinoma between LPD (20.7 months) and RPD (22.7 months; log-rank P = 0.445). The 1- and 3-year overall survival rates were 74 and 31% for LPD and 71 and 33% for RPD. CONCLUSION: In this national cohort of patients, LPD and RPD were associated with equivalent perioperative, pathological, and mid-term oncological outcomes.