Dynamic volume-outcome association for esophagectomies: Do current volume thresholds still apply?

BACKGROUND: It is unknown if the current minimum case volume recommendation of 20 cases per year per hospital is applicable to contemporary practice. METHODS: Patients undergoing esophageal resection between 2005 and 2015 were identified in the National Cancer Database. High, medium, and low-volume hospital strata were defined by quartiles. Adjusted odds ratios and adjusted 30-day mortality between low-, medium-, and high-volume hospitals were calculated using logistic regression analyses and trended over time. RESULTS: Only 1.1% of hospitals had ≥20 annual cases. The unadjusted 30-day mortality for esophagectomy was 3.8% overall. Unadjusted and adjusted 30-day mortality trended down for all three strata between 2005 and 2015, with disproportionate decreases for low-volume and medium-volume versus high-volume hospitals. By 2015, adjusted 30-day mortality was similar in medium- and high-volume hospitals (odds ratio 1.35, 95% confidence interval 0.96-1.91). For hospitals with 20 or more annual cases the adjusted 30-day mortality was 2.7% overall. To achieve this same 30-day mortality the minimum volume threshold had lowered to 7 annual cases by 2015. CONCLUSION: Only 1.1% of hospitals meet current volume recommendations for esophagectomy. Differential improvements in postoperative mortality at low- and medium- versus high-volume hospitals have led to 7 cases in 2015 achieving the same adjusted 30-day mortality as 20 cases in the overall cohort. Lowering volume thresholds for esophagectomy in contemporary practice would potentially increase the proportion of hospitals able to meet volume standards and increase access to quality care without sacrificing quality.

Contemporary Approaches to the Surgical Management of Pancreatic Neuroendocrine Tumors.

The incidence of pancreatic neuroendocrine tumors (PNETs) is on the rise primarily due to the increasing use of cross-sectional imaging. Most of these incidentally detected lesions are non-functional PNETs with a small proportion of lesions being hormone-secreting, functional neoplasms. With recent advances in surgical approaches and systemic therapies, the management of PNETs have undergone a paradigm shift towards a more individualized approach. In this manuscript, we review the histologic classification and diagnostic approaches to both functional and non-functional PNETs. Additionally, we detail multidisciplinary approaches and surgical considerations tailored to the tumor's biology, location, and functionality based on recent evidence. We also discuss the complexities of metastatic disease, exploring liver-directed therapies and the evolving landscape of minimally invasive surgical techniques.

Distinguishing Clinical From Statistical Significances in Contemporary Comparative Effectiveness Research.

OBJECTIVE: To determine the prevalence of clinical significance reporting in contemporary comparative effectiveness research (CER). BACKGROUND: In CER, a statistically significant difference between study groups may or may not be clinically significant. Misinterpreting statistically significant results could lead to inappropriate recommendations that increase health care costs and treatment toxicity. METHODS: CER studies from 2022 issues of the Annals of Surgery , Journal of the American Medical Association , Journal of Clinical Oncology , Journal of Surgical Research , and Journal of the American College of Surgeons were systematically reviewed by 2 different investigators. The primary outcome of interest was whether the authors specified what they considered to be a clinically significant difference in the "Methods." RESULTS: Of 307 reviewed studies, 162 were clinical trials and 145 were observational studies. Authors specified what they considered to be a clinically significant difference in 26 studies (8.5%). Clinical significance was defined using clinically validated standards in 25 studies and subjectively in 1 study. Seven studies (2.3%) recommended a change in clinical decision-making, all with primary outcomes achieving statistical significance. Five (71.4%) of these studies did not have clinical significance defined in their methods. In randomized controlled trials with statistically significant results, sample size was inversely correlated with effect size ( r = -0.30, P = 0.038). CONCLUSIONS: In contemporary CER, most authors do not specify what they consider to be a clinically significant difference in study outcome. Most studies recommending a change in clinical decision-making did so based on statistical significance alone, and clinical significance was usually defined with clinically validated standards.

Bariatric Surgery and Longitudinal Cancer Risk: A Review.

Importance: Cancer is one of the leading causes of death in the United States, with the obesity epidemic contributing to its steady increase every year. Recent cohort studies find an association between bariatric surgery and reduced longitudinal cancer risk, but with heterogeneous findings. Observations: This review summarizes how obesity leads to an increased risk of developing cancer and synthesizes current evidence behind the potential for bariatric surgery to reduce longitudinal cancer risk. Overall, bariatric surgery appears to have the strongest and most consistent association with decreased incidence of developing breast, ovarian, and endometrial cancers. The association of bariatric surgery and the development of esophageal, gastric, liver, and pancreas cancer is heterogenous with studies showing either no association or decreased longitudinal incidences. Conversely, there have been preclinical and cohort studies implying an increased risk of developing colon and rectal cancer after bariatric surgery. A review and synthesis of the existing literature reveals epidemiologic shortcomings of cohort studies that potentially explain incongruencies observed between studies. Conclusions and Relevance: Studies examining the association of bariatric surgery and longitudinal cancer risk remain heterogeneous and could be explained by certain epidemiologic considerations. This review provides a framework to better define subgroups of patients at higher risk of developing cancer who would potentially benefit more from bariatric surgery, as well as subgroups where more caution should be exercised.

Accuracy of DOTATATE PET imaging in the preoperative planning of small bowel neuroendocrine tumor resection.

BACKGROUND AND OBJECTIVES: We assessed the accuracy of preoperative gallium-68 DOTA-Tyr3-octreotate (DOTATATE) positron emission tomography (PET) imaging in estimating multifocality and nodal metastases of small bowel neuroendocrine tumors (sbNETs). METHODS: A multicenter analysis was performed on patients with sbNETs who underwent preoperative DOTATATE PET imaging and surgical resection, with manual palpation of the entire length of the small bowel, between January 2016 and August 2022. Preoperative imaging reports and blinded secondary imaging reviews were compared to the final postoperative pathology reports. Descriptive statistics were applied. RESULTS: One-hundred and four patients met inclusion criteria. Pathology showed 53 (51%) patients had multifocal sbNETs and 96 (92%) had nodal metastases. The original preoperative DOTATATE PET imaging identified multifocal sbNET in 28 (27%) patients and lymph node (LN) metastases in 80 (77%) patients. Based on original radiology reports, sensitivity for multifocal sbNET identification was 45%, specificity was 92%, positive predictive value (PPV) was 86%, and negative predictive value (NPV) was 62%. For the identification of LN metastases, sensitivity was 82%, specificity was 88%, PPV was 99%, and NPV was 29%. CONCLUSIONS: Although DOTATATE PET imaging is specific and relatively accurate, sensitivity and NPV are insufficient to guide surgical planning. Preoperative use should not replace open palpation to identify additional synchronous lesions or to omit regional lymphadenectomy.

Modern Impact of Surgery Journals: Associations Between Impact Factor, H5-Index, and Altmetric Score.

INTRODUCTION: While impact factor (IF) remains the "gold standard" metric for journal quality, newer metrics are gaining popularity. These include the H5-index and journal Altmetric Attention Score (AAS). We explored the relationship between the IF, H5-index, and AAS for core general surgery (GS) and subspecialty journals. METHODS: For all GS and subspecialty journals with a Clarivate IF, H5-index (January 1, 2017, to December 31, 2021) and journal AAS were obtained. Journal Twitter presence and activity was sourced from Twitter and the Twitter application programming interface. Spearman's correlations were assessed for numeric variables. RESULTS: A total of 105 journals were included, around half (49/105; 46.7%) of which were core GS journals. Median IF was 2.48 and median H5-index 19. Journal IF demonstrated a strong correlation with H5-index overall (r = 0.81), though this ranged from r = 0.95 (P < 0.01) for vascular surgery to r = 0.77 (P < 0.01) for plastic surgery journals. AAS was moderately correlated with the IF and H5-index (r = 0.59 and 0.62, respectively; both P < 0.01). R2 values ranging indicated that 66% of the variation in the H5-index and 35% of the variation in AAS was explained by the IF. Just over half the journals had a Twitter account (54/105; 51.4%). Journals with a Twitter account also had a significantly higher IF, H5-index, and AAS than those without a Twitter account (all P < 0.01). AAS was moderately correlated with Twitter activity (r = 0.59) and Twitter followers (r = 0.69). CONCLUSIONS: Across GS and subspecialty journals, journal IF correlates strongly with the H5-index and moderately with AAS. However, only 35% of variation in AAS and 66% of variation in the H5-index is explained by the IF, indicating that these metrics measure unique aspects of journal quality. The future growth of surgical journals should be geared towards improving across multiple metrics, including both the conventional and the contemporary, while leveraging social media to improve readership and eventual academic impact.

Understanding Variation in In-hospital Mortality After Major Surgery in the United States.

OBJECTIVES: We aimed to quantify the contributions of patient characteristics (PC), hospital structural characteristics (HC), and hospital operative volumes (HOV) to in-hospital mortality (IHM) after major surgery in the United States (US). BACKGROUND: The volume-outcome relationship correlates higher HOV with decreased IHM. However, IHM after major surgery is multifactorial, and the relative contribution of PC, HC, and HOV to IHM after major surgery is unknown. STUDY DESIGN: Patients undergoing major pancreatic, esophageal, lung, bladder, and rectal operations between 2006 and 2011 were identified from the Nationwide Inpatient Sample linked to the American Hospital Association survey. Multilevel logistic regression models were constructed using PC, HC, and HOV to calculate attributable variability in IHM for each. RESULTS: Eighty thousand nine hundred sixty-nine patients across 1025 hospitals were included. Postoperative IHM ranged from 0.9% for rectal to 3.9% for esophageal surgery. Patient characteristics contributed most of the variability in IHM for esophageal (63%), pancreatic (62.9%), rectal (41.2%), and lung (44.4%) operations. HOV explained < 25% of variability for pancreatic, esophageal, lung, and rectal surgery. HC accounted for 16.9% and 17.4% of the variability in IHM for esophageal and rectal surgery. Unexplained variability in IHM was high in the lung (44.3%), bladder (39.3%), and rectal (33.7%) surgery subgroups. CONCLUSIONS: Despite recent policy focus on the volume-outcome relationship, HOV was not the most important contributor to IHM for the major organ surgeries studied. PC remains the largest identifiable contributor to hospital mortality. Quality improvement initiatives should emphasize patient optimization and structural improvements, in addition to investigating the yet unexplained sources contributing to IHM.

Socioeconomic and racial disparities in survival for patients with stage IV cancer.

BACKGROUND: Disparities in cancer outcomes for minoritized people and groups experiencing disadvantages with Stage IV cancer is largely unknown. METHODS: Patients with Stage IV pancreatic, colorectal, lung, breast, and prostate cancer were identified from 2004 to 2015 in the National Cancer Database. Cox proportional hazard models were used to quantify how demographics and treatments received were associated with overall survival. RESULTS: 903,151 patients were included. Patients who were younger, non-Hispanic White, had private insurance, higher income, or received care at an academic center were more likely to receive surgery, chemotherapy, and/or radiation therapy (p < 0.001). Black patients, those with Medicare, Medicaid, no insurance, and lower income had lower survival rates across all five cancer types (p < 0.001). On multivariable analysis, receipt of surgery, radiation, and chemotherapy attenuated but did not eliminate this worse survival (p < 0.001). CONCLUSIONS: Survival for patients with Stage IV cancer differs by socioeconomic and self-reported racial classifications.

Cancer embryonic antigen (CEA) levels in patients with appendiceal adenocarcinoma predict response to neo-adjuvant chemotherapy and overall survival.

BACKGROUND AND OBJECTIVES: Serum tumor markers are widely used for diagnosis, prognosis, treatment response, and surveillance. Our study evaluated cancer embryonic antigen (CEA) in patients with appendiceal adenocarcinoma. METHODS: The National Cancer Database was reviewed (2004-2011) for patients with surgical treatment for appendiceal adenocarcinoma. Patients were stratified into two groups: normal and elevated CEA. Multivariable adjusted Cox proportional hazards regression analyses were used to determine the independent effect of CEA on survival. RESULTS: Our study consisted of 2867 patients, 54.0% having elevated CEA. Patients with elevated CEA were more likely to have Stage IV disease, be female, and African American; all p < 0.001. Three-year overall survival (OS) was significantly higher with normal CEA (75.5% vs. 62.8%, p < 0.001). On multivariable analysis, elevated CEA was associated with worse survival (hazard ratio 1.49, 95% confidence interval 1.23-1.80). Patients with elevated CEA had improved 3-year OS with neo-adjuvant compared to adjuvant chemotherapy (p = 0.004), while those with normal CEA showed no difference. CONCLUSIONS: In patients with surgically treated appendiceal adenocarcinoma, preoperative elevation in CEA independently predicts decreased 3-year survival and correlates with improved OS with neo-adjuvant therapy. CEA levels should be considered in clinical decision-making regarding neo-adjuvant therapy in patients with appendiceal adenocarcinoma.

Phenotypes of primary hyperparathyroidism: Does parathyroidectomy improve clinical outcomes for all?

BACKGROUND: Primary hyperparathyroidism consists of 3 biochemical phenotypes: classic, normocalcemic, and normohormonal primary hyperparathyroidism. The clinical outcomes of patients with normocalcemic primary hyperparathyroidism and normohormonal primary hyperparathyroidism are not well described. METHOD: A retrospective review of patients who underwent parathyroidectomy at a single institution was performed. A logistical regression analysis of postoperative nephrolithiasis and highest percentage change in dual-energy x-ray absorptiometry scan comparison using Kruskal-Wallis test and Cox proportional hazard analysis of recurrence-free survival were performed. RESULTS: A total of 421 patients were included (340 classic, 39 normocalcemic primary hyperparathyroidism, 42 normohormonal primary hyperparathyroidism). Median follow-up was 8.8 months (range 0-126). Higher rates of multigland disease were seen in normocalcemic primary hyperparathyroidism (64.1%) and normohormonal primary hyperparathyroidism (56.1%) compared to the classic (25.8%), P < .001. There were no differences in postoperative complications. The largest percentage increases in bone mineral density at the first postoperative dual-energy x-ray absorptiometry scan were higher for classic (mean ± SD, 6.4 ± 9.1) and normocalcemic primary hyperparathyroidism (4.8 ± 11.9) compared to normohormonal primary hyperparathyroidism, which remained stable (0.2 ± 14.2). Normocalcemic primary hyperparathyroidism were more likely to experience nephrolithiasis postoperatively, 6/13 (46.2%) compared to 11/68 (16.2%) classic, and 2/13 (15.4%) normohormonal primary hyperparathyroidism, P = .0429. Normocalcemic primary hyperparathyroidism was the only univariate predictor of postoperative nephrolithiasis recurrence (odds ratio [95% confidence interval] 4.44 [1.25-15.77], P = .029). Normocalcemic primary hyperparathyroidism was significantly associated with persistent disease with 6/32 (18.8%) compared to 1/36 (2.8%) and 3/252 (1.2%) in normohormonal primary hyperparathyroidism and classic (P < .001). CONCLUSION: Three phenotypes of primary hyperparathyroidism are distinct clinical entities. Normocalcemic primary hyperparathyroidism had higher incidence of persistent disease and postoperative nephrolithiasis but demonstrated improvements in postoperative bone density. These data should inform preoperative discussions with patients with normocalcemic primary hyperparathyroidism and normohormonal primary hyperparathyroidism regarding postoperative expectations.

Association of Textbook Outcome and Surgical Case Volume with Long-Term Survival in Patients Undergoing Surgical Resection for Pancreatic Cancer.

BACKGROUND: Current literature has identified textbook outcome (TO) as a quality metric after cancer surgery. We studied whether TO after pancreatic resection has a stronger association with long-term survival than individual hospital case volume. STUDY DESIGN: Patients undergoing surgery for pancreatic adenocarcinoma from 2010 to 2015 were identified from the National Cancer Database. Hospitals were stratified by volume (low less than 6, medium 6 to 19, and high 20 cases or more per year), and overall survival data were abstracted. We defined TO as adequate lymph node count, negative margins, length of stay less than the 75th percentile, appropriate systemic therapy, timely systemic therapy, and without a mortality event or readmission within 30 days. The association of TO and case volume was assessed using a multivariable Cox regression model for survival. RESULTS: Overall, 7270 patients underwent surgery, with 30.7%, 48.7%, and 20.6% performed at low-, medium-, and high-volume hospitals, respectively. Patients treated at low-volume hospitals were more likely to be Black, be uninsured or on Medicaid, have higher Charlson comorbidity scores, and be less likely to achieve TO (23.4% TO achievement vs 37.5% achievement at high-volume hospitals). However, high hospital volume was no longer associated with overall survival once TO was added to the multivariable model stratified by volume status. Achievement of TO corresponded to a 31% decrease in mortality (hazard ratio 0.69; p < 0.001), independent of hospital volume. CONCLUSIONS: Improved long-term survival after pancreatic resection was associated with TO rather than high hospital volume. Quality improvement efforts focused on TO criteria have the potential to improve outcomes irrespective of case volume.

Trends in Reimbursement for Index Surgical Oncology Procedures in Contemporary Practice: Declining Reimbursement for Surgical Oncology Procedures-How Low Do We Go?

BACKGROUND: Comprehensive trends in Medicare reimbursement, increasingly relevant to current and future surgical oncology practice, have not been well studied. OBJECTIVE: The aim of this study was to analyze Medicare reimbursement for index surgical oncology procedures between 2007 and 2021. METHODS: Using the Physician Fee Schedule Look-Up Tool from the Centers for Medicare and Medicaid Services, reimbursement data from 2007 to 2021 were obtained for 23 index surgical oncology procedures. Total change in Medicare reimbursement, yearly rates of change, and compound annual growth rate were then calculated. All data were corrected for inflation using the consumer price index. Subset analysis was performed to assess the most recent 5-year trends. RESULTS: Overall reimbursement for the index surgical oncology procedures increased by an average of 21.6% from 2007 to 2021. After correcting for inflation, average reimbursement decreased to - 8.6%, with the greatest decline seen for thyroid surgery (- 16.9%). Breast surgery was the only category to experience an increase in adjusted reimbursement (9.0%). The average compound annual growth rate for all procedures was - 0.68% from 2007 to 2021. In the most recent 5-year subanalysis, the yearly decrease in inflation-adjusted Medicare reimbursement averaged - 2.47% per year, in comparison with the - 0.60% overall rate of yearly decline (p < 0.005). CONCLUSION: Adjusted Medicare reimbursement for surgical oncology procedures decreased steadily from 2007 to 2021, with an accelerating trend over the last 5 years. As the Medicare population increases, surgical oncologists need to understand these trends so they may consider practice implications, advocate for proper reimbursement models, and preserve access to surgical oncology services.

Oncologic Outcomes of Multi-Institutional Minimally Invasive Inguinal Lymph Node Dissection for Melanoma Compared with Open Inguinal Dissection in the Second Multicenter Selective Lymphadenectomy Trial (MSLT-II).

BACKGROUND: Minimally invasive inguinal lymphadenectomy (MILND) is safe and feasible, but limited data exist regarding oncologic outcomes. METHODS: This study performed a multi-institutional retrospective cohort analysis of consecutive MILND performed for melanoma between January 2009 and June 2016. The open ILND (OILND) comparative cohort comprised patients enrolled in the second Multicenter Selective Lymphadenectomy Trial (MSLT-II) between December 2004 and March 2014.The pre-defined primary end point was the same-basin regional nodal recurrence, calculated using properties of binomial distribution. Time to events was calculated using the Kaplan-Meier method. The secondary end points were overall survival, progression-free survival, melanoma-specific survival (MSS), and distant metastasis-free survival (DMFS). RESULTS: For all the patients undergoing MILND, the same-basin regional recurrence rate was 4.4 % (10/228; 95 % confidence interval [CI], 2.1-7.9 %): 8.2 % (4/49) for clinical nodal disease and 3.4 % (6/179) for patients with a positive sentinel lymph node (SLN) as the indication. For the 288 patients enrolled in MSLT-II who underwent OILND for a positive SLN, 17 (5.9 %) had regional node recurrence as their first event. After controlling for ulceration, positive LN count and positive non-SLNs at the time of lymphadenectomy, no difference in OS, PFS, MSS or DMFS was observed for patients with a positive SLN who underwent MILND versus OILND. CONCLUSION: This large multi-institutional experience supports the oncologic safety of MILND for melanoma. The outcomes in this large multi-institutional experience of MILND compared favorably with those for an OILND population during similar periods, supporting the oncologic safety of MILND for melanoma.

Parathyroidectomy in the elderly is beneficial and safe with similar improvements in postoperative bone mineral density.

BACKGROUND: This study evaluated bone health outcomes of parathyroidectomy in elderly primary hyperparathyroidism (pHPT) patients. METHODS: A retrospective review was performed of parathyroidectomy patients with pHPT at a single institution from 2010 to 2019. Bone mineral density (BMD) improvements at postoperative dual-energy X-ray absorptiometry (DEXA) scans were analyzed between groups aged ≥75 and < 75 years using 1:1 matching on preoperative BMD. RESULTS: Patients ≥75 had BMD improvements through the second postoperative DEXA scans. While mean T-scores slightly improved in the ≥75 group during the study period, T-score improvement was more significant in the <75 group at first and third postoperative DEXA scans with +0.7 < 75 and +0.1 improvements ≥75 by the third DEXA (p = 0.026). Postoperative fragility fracture rates were similar in the ≥75 group, but significantly improved in patients <75 (10.4% preoperatively to 1.4% postoperatively, p = 0.020). Both cohorts had low complication rates with recurrent laryngeal nerve injury and permanent hypocalcemia of <1% (p = 0.316). CONCLUSIONS: Postoperative BMD improvement was similar between the two cohorts with no difference in complication rates suggesting parathyroidectomy is safe and effective in the elderly.

Readmissions From Venous Thromboembolism After Complex Cancer Surgery.

IMPORTANCE: Venous thromboembolism (VTE) is a major cause of preventable morbidity and mortality after cancer surgery. Venous thromboembolism events that are significant enough to require hospital readmission are potentially life threatening, yet data regarding the frequency of these events beyond the 30-day postoperative period remain limited. OBJECTIVE: To determine the rates, outcomes, and predictive factors of readmissions owing to VTE up to 180 days after complex cancer operations, using a national data set. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study of the 2016 Nationwide Readmissions Database was performed to study adult patients readmitted with a primary VTE diagnosis. Data obtained from 197 510 visits for 126 104 patients were analyzed. This was a multicenter, population-based, nationally representative study of patients who underwent a complex cancer operation (defined as cystectomy, colectomy, esophagectomy, gastrectomy, liver/biliary resection, lung/bronchus resection, pancreatectomy, proctectomy, prostatectomy, or hysterectomy) from January 1 through September 30, 2016, for a corresponding cancer diagnosis. EXPOSURES: Readmission with a primary diagnosis of VTE. MAIN OUTCOMES AND MEASURES: Proportion of 30-, 90-, and 180-day VTE readmissions after complex cancer surgery, factors associated with readmissions, and outcomes observed during readmission visit, including mortality, length of stay, hospital cost, and readmission to index vs nonindex hospital. RESULTS: For the 126 104 patients included in the study, 30-, 90-, and 180-day VTE-associated readmission rates were 0.6% (767 patients), 1.1% (1331 patients), and 1.7% (1449 of 83 337 patients), respectively. A majority of patients were men (58.7%), and the mean age was 65 years (SD, 11.5 years). For the 1331 patients readmitted for VTE within 90 days, 456 initial readmissions (34.3%) were to a different hospital than the index surgery hospital, median length of stay was 5 days (IQR, 3-7 days), median cost was $8102 (IQR, $5311-$10 982), and 122 patients died (9.2%). Independent factors associated with readmission included type of operation, scores for severity and risk of mortality, age of 75 to 84 years (odds ratio [OR], 1.30; 95% CI, 1.02-1.78), female sex (OR, 1.23; 95% CI, 1.11-1.37), nonelective index admission (OR, 1.31; 95% CI, 1.03-1.68), higher number of comorbidities (OR, 1.30; 95% CI, 1.06-1.60), and experiencing a major postoperative complication during the index admission (OR, 2.08; 95% CI, 1.85-2.33). CONCLUSIONS AND RELEVANCE: In this cohort study, VTE-related readmissions after complex cancer surgery continued to increase well beyond 30 days after surgery. Quality improvement efforts to decrease the burden of VTE in postoperative patients should measure and account for these late VTE-related readmissions.

Identifying the Optimal case-volume threshold for pancreatectomy in contemporary practice.

BACKGROUND: The volume-mortality association led to regionalization recommendations for pancreatic surgery. Mortality following pancreatectomy has declined, but case-volume thresholds remain unchanged. METHODS: Patients undergoing pancreatectomy from 2004 to 2013 were identified in the National Cancer Database (NCDB). Hospitals were divided into low (LV), medium (MV), and high-volume (HV) strata using 30-day mortality quartiles and logistic regression with cubic splines. Adjusted absolute difference and odds of 30-day mortality between strata were calculated. RESULTS: Annual volumes for LV, MV, and HV were <4, 4-18 and > 18 cases using quartiles and <6, 6-18 and > 18 using cubic splines. Absolute 30-day mortality trended downwards, with differential improvements for MV and LV. Benchmark 30-day mortality for hospitals with >18 cases was 2.8%. For this benchmark, the case-volume threshold decreased from 31 in 2004 to 6 in 2013. CONCLUSION: Differential improvement in 30-day mortality at LV and MV hospitals led to similar 30-day mortality odds at MV and HV hospitals by 2013.

Formative Feedback with In-Class Question Bank Utilization Improves Resident Satisfaction with General Surgery Didactics.

BACKGROUND: Formative feedback provides low-stakes opportunities for educational improvement. To enrich our basic science didactics, formative feedback measures were incorporated into our didactics using mobile devices. MATERIALS AND METHODS: Lecture changes included institutional paid access to a commercial question bank, a 5-item in-class pre-didactic quiz curated from the question bank and taken on the resident's mobile device, and group discussion of quiz topics. An anonymous survey was sent to participating residents. RESULTS: Overall response rate was 71% among residents. All reported that the new lecture format was a valuable addition to the basic science curriculum (100% Agree/Strongly Agree), and formative assessments provided valuable feedback about the progress of their learning (Strongly Agree = 42%, Agree =58%). All residents reported that in-class use of their mobile device for quizzes was convenient, with majority (84%) preferring it over paper printouts. Residents were more motivated to study before lecture (Strongly Agree = 42%, Agree =42%), with majority also reporting the new format helped identify weaknesses in their knowledgebase (Strongly Agree = 58%, Agree =33%). While majority of residents agreed that quizzes motivated them to study more after lecture, a large portion disagreed (42%). Majority of senior residents reported that the process of composing quizzes prior to lecture enriched their own learning (57%) and helped them find gaps in their knowledge (71%). CONCLUSION: Incorporating a commercial question bank within didactics gives general surgery residents formative feedback and encourages learning outside the classroom, leading to improved satisfaction with basic science didactics.

Lymph node positivity and association with long-term survival for different histologies of appendiceal cancer.

BACKGROUND: Appendiceal cancers represent a diverse group of malignancies with varying biological behavior. The significance of lymph node metastases in relation to long-term survival and chemotherapy response is poorly defined. METHODS: The National Cancer Database was queried to find patients diagnosed with appendiceal cancer from 1998 to 2012. Kaplan-Meier curves and multivariable Cox regression analyses were used to study the association between lymph node status and overall survival. Stage IV patients were excluded. RESULTS: The rate of nodal positivity of the 9841 patients with known node status was: signet ring 47.4%, carcinoid 42.3%, nonmucinous adenocarcinoma 28.8%, goblet cell 21.9%, and mucinous adenocarcinoma 20.4%. Node-positive patients had worse long-term survival for all subtypes with the exception of carcinoid tumors (p < 0.001). The strongest association was for signet cell and goblet cell. Adjuvant chemotherapy in node-positive patients improved survival for mucinous, nonmucinous, and signet ring cell histology (p < 0.01), but not for goblet cell. CONCLUSIONS: Nodal involvement in patients with appendiceal cancer varies in incidence, association with adverse survival, and response to systemic therapy. Individualized treatment algorithms for the management of the subtypes of appendiceal cancer are needed.

A Predictive Model for Nodal Metastases in Patients With Appendiceal Cancers.

BACKGROUND: Histologic subtypes of appendiceal cancer vary in their propensity for metastases to regional lymph nodes (LN). A predictive model would help direct subsequent surgical therapy. METHODS: The National Cancer Database was queried for patients with appendiceal cancer undergoing surgery between 1998 and 2012. Multivariable logistic regression was used to develop a predictive model of LN metastases which was internally validated using Brier score and Area under the Curve (AUC). RESULTS: A total of 21,647 patients were identified, of whom 9079 (41.9%) had node negative disease, 4575 (21.1%) node positive disease, and 7993 (36.9%) unknown LN status. The strongest predictors of LN positivity were histology (carcinoid tumors OR 12.78, 95% CI 9.01-18.12), increasing T Stage (T3 OR 3.36, 95% CI 2.52-4.50, T4 OR 6.30, 95% CI 4.71-8.42), and tumor grade (G3 OR 5.55, 95% CI 4.78-6.45, G4 OR 5.98, 95% CI 4.30-8.31). The coefficients from the regression analysis were used to construct a calculator that generated predicted probabilities of LN metastases given certain inputs. Internal validation of the overall model showed an AUC of 0.75 (95% CI 0.74-0.76) and Brier score of 0.188. Histology-specific predictive models were also constructed with an AUC that varied from 0.669 for signet cell to 0.75 for goblet cell tumors. CONCLUSIONS: The risk for nodal metastases in patients with appendiceal cancers can be quantified with reasonable accuracy using a predictive model incorporating patient age, sex, tumor histology, T-stage, and grade. This can help inform clinical decision making regarding the need for a right hemicolectomy following appendectomy.