A Comparison of Open and Minimally Invasive Surgery for Hepatic and Pancreatic Resections Among the Medicare Population

INTRODUCTION

Minimally invasive surgery (MIS) has become standard of care for many gastrointestinal surgical procedures. Despite possible clinical benefits, MIS may be underutilized in some populations. The aim of this study was to access the utilization of MIS among Medicare patients undergoing hepatopancreatic procedures and define clinical outcomes, as well as costs, of minimally invasive techniques compared with the conventional open approach.

METHODS

The Medicare Provider Analysis and Review (MEDPAR) Inpatient Files were reviewed to identify Medicare patients who underwent pancreatic and liver procedures between 2013 and 2015. Primary outcomes of the analysis included perioperative clinical outcomes such as rates of complications, index hospitalization length-of-stay (LOS), failure-to-rescue, rates, and causes of 90-day readmission, as well as 90-day mortality. Secondary outcomes were Medicare payments for index hospitalization and readmission. Multivariable logistic regression was used to investigate the impact of MIS on clinical outcomes and health expenditures.

RESULTS

A total of 13,716 (90.6%) patients underwent open resection, while MIS was performed in 1424 (9.4%) patients. LOS was shorter among patients undergoing MIS (mean 7.3 ± SD 7.3) versus open (mean 9.3 ± SD 9.1) surgery (p < 0.001). The incidence of perioperative complications was lower following MIS (open 25.5%, n = 3492 vs. MIS 17.2%, n = 245) (p < 0.001). Rates of failure-to-rescue were similar among patients undergoing an open versus MIS pancreatic procedure (open 19.4%, n = 271 vs. MIS 13.4%, n = 17) (p = 0.09). In contrast, 90-day readmission (open 31.1%, n = 1630 vs. MIS 24.1%, n = 201, p < 0.001), as well as 90-day mortality (open 7.7%, n = 404 vs. MIS 4.2%, n = 35, p < 0.001) were lower among patients undergoing pancreatic resections via an MIS approach. In contrast, failure-to-rescue and readmission, as well as mortality, were all comparable among patients undergoing a liver resection, regardless as to whether the operation was performed open or via an MIS approach (all p > 0.05). Mean total payments for open pancreatic surgery were on average $1421 higher in the open versus MIS pancreatic group (p = 0.01); in contrast, there was no difference in the overall payment for hepatic resection (p > 0.05).

CONCLUSION

The MIS approach was underutilized among patients undergoing liver and pancreatic procedures. MIS was associated with lower complication and readmission and shorter LOS, as well as comparable/slightly lower Medicare payments, compared with the open approach. The MIS approach should strongly be considered among older patients undergoing liver and pancreatic procedures.

Perioperative use of blood products is associated with risk of morbidity and mortality after surgery

BACKGROUND

Administration of blood products may be associated with increased morbidity and perioperative mortality in surgical patients.

METHODS

Patients aged 18 + who underwent gastrointestinal surgery at the Ohio State University Wexner Medical Center 9/10/2015-5/9/2018 were identified. Multivariable logistic regression models were used to evaluate impact of blood product use on survival and complications, as well as to identify factors associated with receipt of transfusions.

RESULTS

Among 10,756 patients, 35,517 units of blood products were transfused. Preoperative nadir hemoglobin was associated with receipt of blood product transfusion (OR 0.55, 95% CI 0.53, 0.68). After adjusting for patient and procedural characteristics, patients undergoing transfusion of blood products had an increased risk of perioperative mortality (OR 7.80, 95% CI 6.02, 10.10).

CONCLUSIONS

The use of blood products was associated with increased risk of complication and death. Patient blood management programs should be implemented to provide rational criteria and guidance for the transfusion of blood products.

Specific Medicare Severity-Diagnosis Related Group Codes Increase the Predictability of 30-Day Unplanned Hospital Readmission After Pancreaticoduodenectomy

BACKGROUND

The Medicare Severity-Diagnosis Related Group coding system (MS-DRG) is routinely used by hospitals for reimbursement purposes following pancreatic surgery. We aimed to determine whether specific pancreatectomy MS-DRG codes, when combined with distinct clinicopathologic and perioperative characteristics, increased the accuracy of predicting 30-day readmission after pancreaticoduodenectomy (PD).

METHODS

Demographic, clinicopathologic, and perioperative factors were compared between readmitted and non-readmitted patients at Brigham and Women's Hospital following PD. Different pancreatectomy DRG codes, currently used for reimbursement purposes [407: without complication/co-morbidity (CC), 406: with CC, and 405: with major CC] were combined with clinical factors to assess their predictability of readmission. Univariate and multivariable analyses were performed to evaluate outcomes.

RESULTS

Among 354 patients who underwent PD between 2010 and 2017, 69 (19%) were readmitted. The incidence of readmission was 13, 32, and 55% for patients with assigned DRG codes 407, 406, and 405, respectively (P = 0.0395). Readmitted patients were more likely to have had T4 disease (P = 0.0007), a vascular resection (P = 0.0078), and longer operative times (P = 0.012). On multivariable analysis, combining DRG 407 with relevant clinicopathologic factors was unable to predict readmission. In contrast, DRG 406 code among patients with N positive disease (P = 0.0263) and LOS > 10 days (P = 0.0505) was associated with readmission. DRG 405, preoperative obstructive jaundice (OR: 7.5, CI: 1.5-36, P = 0.0130), vascular resection (OR: 7.7, CI: 1.1-51, P = 0.0336), N positive stage of disease (OR: 0.2, CI: 0-0.9, P = 0.0447), and operative time > 410 min (OR: 5.9, CI: 1-32, P = 0.0399) were each strongly associated with 30-day readmission after PD [likelihood ratio (LR) < 0.0001].

CONCLUSIONS

Distinct pancreatectomy MS-DRG classification codes (405), combined with relevant clinicopathologic and perioperative characteristics, strongly predicted 30-day readmission after PD. DRG classification algorithms can be implemented to more accurately identify patients at a higher risk of readmission.

Synergistic Effects of Perioperative Complications on 30-Day Mortality Following Hepatopancreatic Surgery

BACKGROUND

Data on the interaction effect of multiple concurrent postoperative complications relative to the risk of short-term mortality following hepatopancreatic surgery have not been reported. The objective of the current study was to define the interaction effect of postoperative complications among patients undergoing HP surgery on 30-day mortality.

METHODS

Using the ACS-NSQIP Procedure Targeted Participant Use Data File, patients who underwent HP surgery between 2014 and 2016 were identified. Hazard ratios (HRs) for 30-day mortality were estimated using Cox proportional hazard models. Two-way interaction effects assessing combinations of complications relative to 30-day mortality were calculated using the relative excess risk due to interaction (RERI) in separate adjusted Cox models.

RESULTS

Among 26,824 patients, 10,886 (40.5%) experienced at least one complication. Mortality was higher among patients who experienced at least one complication versus patients who did not experience a complication (3.0 vs 0.1%, p < 0.001). The most common complications were blood transfusion (16.9%, n = 4519), organ space infection (12.2%, n = 3273), and sepsis/septic shock (8.2%, n = 2205). Combinations associated with additive effect on mortality included transfusion + renal dysfunction (RERI 12.3, 95% CI 5.2-19.4), pulmonary dysfunction + renal dysfunction (RERI 60.9, 95% CI 38.6-83.3), pulmonary dysfunction + cardiovascular complication (RERI 144.1, 95% CI 89.3-199.0), and sepsis/septic shock + renal dysfunction (RERI 11.5, 95% CI 4.4-18.7).

CONCLUSION

Both the number and specific type of complication impacted the incidence of postoperative mortality among patients undergoing HP surgery. Certain complications interacted in a synergistic manner, leading to a greater than expected increase in the risk of short-term mortality.

Pre-operative Sarcopenia Identifies Patients at Risk for Poor Survival After Resection of Biliary Tract Cancers

INTRODUCTION

Biliary tract cancers (BTC) are aggressive malignancies that require complex surgical procedures. Patients with BTC can present with skeletal muscle depletion, yet the effects of muscle wasting (sarcopenia) on outcomes have not been well studied. The objective of the current study was to define the impact of sarcopenia on survival among patients undergoing resection of BTC.

METHODS

Patients who underwent exploration for BTC who had a pre-operative CT scan available for review were identified. Body composition variables including total and psoas muscle area (cm²), muscle density (Hounsfield units), visceral fat area, subcutaneous fat area, and waist-to-hip ratio were analyzed at the level of L3. Outcomes were assessed according to the presence or absence of sarcopenia defined using sex- and BMI-specific threshold values for Psoas Muscle Index (PMI, cm²/m²).

RESULTS

Among 117 patients with BTC, 78 (67%) underwent curative-intent resection and 39 (33%) were explored but did not undergo resection due to metastatic/locally advanced disease. Tumor type included distal cholangiocarcinoma (n = 18, 15.4%), hilar cholangiocarcinoma (n = 27, 23.1%), gallbladder carcinoma (n = 52, 44.4%), and intrahepatic cholangiocarcinoma (n = 20, 17.1%). Median patient age was 65.6 years and 43.6% were male. Mean patient BMI was 26.1 kg/m² among men and 27.5 kg/m² among women. Overall, 41 (35.0%) patients had sarcopenia. Sarcopenia was associated with an increased risk of death among patients who underwent resection (HR 3.52, 95%CI 1.60-7.78, p = 0.002), which was comparable to patients with unresectable metastatic disease. Other factors such as low serum albumin (HR 3.17, 95% CI 1.30-7.74, p = 0.011) and low psoas density (HR 2.96, 95% CI 1.21-7.21, p = 0.017) were also associated with increased risk of death. Survival was stratified based on sarcopenia, psoas density, and serum albumin. The presence of each variable was associated with an incremental increased risk of death (0 variables ref.; 1 variable HR 3.8, 95% CI 1.0-14, p = 0.043; 2 variables HR 13.1, 95% CI 3.0-57.7, p = 0.001; 3 variables HR 14.6, 95% CI 2.5-87.1, p = 0.003). Patients who had no adverse prognostic factors had a 3-year OS of 67% versus no survival among patients with all 3 factors.

CONCLUSIONS

Sarcopenia was common among patients undergoing resection of BTC, occurring in 1 of every 3 patients. Sarcopenia was associated with poor survival after resection, particularly among patients who experienced a recurrence. Body composition metrics such as sarcopenia and low psoas muscle density in addition to low albumin level were able to stratify patients into different prognostic categories.

Role of associating liver partition and portal vein ligation in staged hepatectomy (ALPPS)-strategy for colorectal liver metastases

Colorectal carcinoma (CRC) is the third leading cause of cancer-related death in the United States. The liver is the most frequent site of metastasis and a key determinant of survival in patients with isolated colorectal liver metastasis (CRLM). Surgical resection remains the only hope for prolonged survival in patients with CRLM. However, most patients are deemed to be unresectable at presentation due to a small future liver remnant (FLR) and fear of post-hepatectomy liver failure. Procedures such as portal vein ligation or embolization (PVL/PVE) followed by hepatectomy have been established as standard methods to increase FLR volume, but have limitations dependent upon extent of disease and patient's ability to grow the liver remnant. Recently, associating liver partition and portal vein ligation in staged hepatectomy (ALPPS) has been introduced as a technique to induce liver hypertrophy over a shorter time period. Being a complex two-stage surgical procedure, initial reports of higher ALPPS-associated complications and mortality limited its worldwide adoption by hepatobiliary surgeons. However, recent studies have showed ALPPS superiority over conventional procedures in terms of feasibility and inducing liver hypertrophy, with comparable morbidity and mortality. We herein review the role of ALPPS in management of patients with CRLM.

Perioperative complications and the cost of rescue or failure to rescue in hepato-pancreato-biliary surgery

BACKGROUND

It is unclear how either the successful or failed rescue of hepato-pancreato-biliary (HPB) patients from complications impacts costs.

METHODS

A retrospective cohort study of HPB surgical patients was performed using claims data from 2013 to 2015 in the Medicare Provider Analysis and Review (MEDPAR) database. Patient demographics, characteristics, outcomes and risk-adjusted Medicare payments were compared.

RESULTS

11,596 patients were identified. Over half of the patients (n = 5,810, 50.1%) underwent liver surgery, while 42% (n = 4892) had pancreatic and 8% (n = 894) had biliary operations. The overall complication rate varied (liver: 19.6%; pancreas: 20.3%; biliary: 25.2%, p = 0.001). In general, both minor and serious complications resulted in higher Medicare payments. Failed rescue led to higher average Medicare payments during index hospitalization compared to successful rescue ($53,476 versus $44,636, p < 0.001). The reverse was true on readmission; successful rescue was associated with higher average Medicare payments ($25,746 versus $15,654, p < 0.001). Taken together (index plus readmission), total hospitalization payments were higher for failed compared to successful rescue ($66,604 versus $52,143, p < 0.001).

CONCLUSION

Following HPB surgery, there is a significant cost associated with both rescue and failure-to-rescue from perioperative complications. Total hospitalization cost was highest for patients who experienced failure-to-rescue.

The Impact of Discharge Timing on Readmission Following Hepatopancreatobiliary Surgery: a Nationwide Readmission Database Analysis

OBJECTIVE

Decreasing hospital length-of-stay (LOS) may be an effective strategy to reduce costs while also improving outcomes through earlier discharge to the non-hospital setting. The objective of the current study was to define the impact of discharge timing on readmission, mortality, and charges following hepatopancreatobiliary (HPB) surgery.

METHODS

The Nationwide Readmissions Database (NRD) was used to identify patients undergoing HPB procedures between 2010 and 2014. Length of stay (LOS) was categorized as early discharge (4-5 days), routine discharge (6-9 days), and late discharge (10-14 days). Univariable and multivariable analyses were utilized to identify factors associated with 90-day readmission.

RESULTS

A total of 28,114 patients underwent HPB procedures. Overall median LOS was 7 days (IQR 5-11); 10,438 (37.1%) patients had an early discharge, while 13,665 (48.6%) and 4011 (14.3%) patients had a routine or late discharge. The probability of early discharge increased over time (referent 2010: 2011-4% (OR 1.04, 95% CI 0.96-1.15) vs. 2012-10% (OR 1.10, 95% CI 1.01-1.20) vs. 2013-21% (OR 1.21, 95% CI 1.11-1.32) vs. 2014-32% (OR 1.32, 95% CI 1.21-1.44)) (p < 0.001). Early discharge was associated with insurance status, diagnosis (benign vs. malignant disease), general health, and overall hospital volume (all p < 0.05). Among patients who had an early discharge, 30- and 90-day readmission was 11.5 and 17.4%, respectively. In contrast, 30- and 90-day readmission was 16.9 and 24.7%, respectively, among patients who had a routine discharge group (p < 0.001). Among patients readmitted within 90 days, in-hospital mortality was similar among patients who had early (n = 43, 2.4%) versus routine discharge (n = 65, 1.9%). Median charges were lower among patients who had an early versus routine versus late discharge ($54,476 [IQR 40,053-79,100] vs. $75,192 [IQR 53,296-113,123] vs. $115,061 [IQR 79,162-171,077], respectively) (p < 0.001).

CONCLUSIONS

Early discharge after HPB surgery was not associated with increased 30- or 90-day readmission. Overall 90-day in-hospital mortality following a readmission was comparable among patients with an early, routine, and late discharge, while median charges were lower in the early discharge group.

Preoperative prognostic nutritional index predicts survival of patients with intrahepatic cholangiocarcinoma after curative resection

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy. We sought to examine the association between preoperative prognostic nutritional index (PNI) and long-term overall survival among patients with ICC who underwent curative-intent resection.

METHODS

Patients who underwent hepatectomy for ICC between 1990 and 2015 were identified using an international multi-institutional database. Clinic-pathological characteristics and long-term outcomes of patients with PNI ≥ 40 and <40 were compared using univariable and multivariable analyses.

RESULTS

Among 637 patients, 53 patients had PNI < 40 (8.3%) and 584 patients had PNI ≥ 40 (91.7%). While there was no difference between PNI groups with regard to tumor size (P = .87), patients with PNI < 40 were more likely to have multifocal disease (PNI < 40, n = 16, 30.2% vs PNI ≥ 40, n = 65, 11.1%; P < 0.001), poorly differentiated or undifferentiated ICC (PNI < 40, n = 13, 25.5% vs PNI ≥ 40, n = 75, 13.1%; P = 0.020) and T2/T3/T4 disease vs patients with PNI ≥ 40 (PNI < 40, n = 38, 71.7% vs PNI ≥ 40, n = 265, 45.4%; P < 0.001). Patients with PNI ≥ 40 had better OS vs patients with PNI < 40 (5-year OS: PNI ≥ 40: 47.5%, 95% CI, 42.2 to 52.6% vs PNI < 40: 24.6%, 95% CI, 12.1 to 39.6%; P < 0.001). On multivariable analysis, PNI < 40 remained associated with increase risk of death (HR, 1.71; 95% CI, 1.15 to 2.53; P = 0.008).

CONCLUSION

A low preoperative PNI was associated with a more aggressive ICC phenotype. After controlling for these factors, PNI remained independently associated with a markedly worse prognosis.

Impact of Post-Discharge Disposition on Risk and Causes of Readmission Following Liver and Pancreas Surgery

BACKGROUND

The relationship between the post-discharge settings and the risk of readmission has not been well examined. We sought to identify the association between discharge destinations and readmission rates after liver and pancreas surgery.

METHODS

The 2013-2015 Medicare-Provider Analysis and Review (MEDPAR) database was reviewed to identify liver and pancreas surgical patients. Patients were subdivided into three groups based on discharge destination: home/self-care (HSC), home with home health assistance (HHA), and skilled nursing facility (SNF). The association between post-acute settings, readmission rates, and readmission causes was assessed.

RESULTS

Among 15,141 liver or pancreas surgical patients, 60% (n = 9046) were HSC, 26.9% (n = 4071) were HHA, and 13.4% (n = 2024) were SNF. Older, female patients and patients with ≥ 2 comorbidities, ≥ 2 previous admissions, an emergent index admission, an index complication, and ≥ 5-day length of stay were more likely to be discharged to HHA or SNF compared to HSC (all P < 0.001). Compared to HSC, HHA and SNF patients had a 34 and a 67% higher likelihood of 30-day readmission, respectively. The HHA and SNF settings were also associated with a 33 and a 69% higher risk of 90-day readmission. There was no association between discharge destination and readmission causes.

CONCLUSION

Among liver and pancreas surgical patients, HHA and SNF patients had a higher risk of readmission within 30 and 90 days. There was no difference in readmission causes and discharge settings. The association between discharge setting and the higher risk of readmission should be further evaluated as the healthcare system seeks to reduce readmission rates after surgery.

The impact of a malignant diagnosis on the pattern and outcome of readmission after liver and pancreatic surgery: An analysis of the nationwide readmissions database

BACKGROUND AND OBJECTIVES

Reducing readmissions is an important quality improvement metric. We sought to investigate patterns of 90-day readmission after hepato-pancreatic (HP) procedures.

METHODS

The Nationwide Readmissions Database (NRD) was used to identify patients undergoing HP procedures between 2010 and 2014. Patients were stratified according to benign versus malignant HP diagnoses and as index (same hospital as operation) versus non-index (different hospital) readmissions.

RESULTS

Among the 41 059 patients who underwent HP procedures, 26 563 (65%) underwent a liver resection while 14 496 (35%) pancreatic resection. Among all patients, 11 902 (29%) had a benign diagnosis versus 29 157 (71%) who had a cancer diagnosis. Overall 90-day readmission was 22% (n = 8 998) with a slight increase in readmissions among patients with a malignant (n = 6 655;23%) versus benign (n = 2 343;20%) diagnosis (P < 0.001). Readmission to an index hospital was more common (n = 7 316 81%) versus a non-index hospital (n = 1 682 19%). Non-index hospital readmissions were more frequent among patients with malignant HP diagnoses (OR, 1.41;P  = 0.001).

CONCLUSIONS

Up to one in four patients were readmitted after HP surgery. Late readmission was more common among patients with a cancer-diagnosis. While most readmissions occurred at the index hospital, 19% of all readmissions occurred at a non-index hospital and were more frequent among patients with malignant diagnoses.

Variation in Medicare Payments and Reimbursement Rates for Hepatopancreatic Surgery Based on Quality: Is There a Financial Incentive for High-Quality Hospitals?

BACKGROUND

To better define the financial impact of high-quality care for payers and hospitals, we compared outcomes and Medicare payments between high-quality (HQ) and low-quality (LQ) hospitals after hepatopancreatic surgery.

STUDY DESIGN

Between 2013 through 2015, a total of 15,874 Medicare beneficiaries underwent hepatopancreatic surgery. Using the entire cohort, multivariable logistic regression was performed to categorize hospitals into quintiles based on the probability of experiencing a major complication; HQ (bottom 20%) and LQ (top 20%) hospitals were identified. Only HQ and LQ hospitals were included in the final propensity matching to compare payments. Major complication was defined as a complication associated with a length of stay of >75th percentile. Incremental payment and cost of complication were estimated using multivariable linear regression.

RESULTS

Major complications occurred in 9.7% (n = 309 of 3,182) at HQ hospitals compared with 20% (n = 625 of 3,130) at LQ hospitals (p < 0.001). The incremental increased payment associated with major complication was $29,640, which was lower than the incremental hospital cost of $42,935. The Medicare reimbursement rate was also 6% lower at both HQ and LQ hospitals when a major complication occurred vs not; however, HQ hospitals had a 3% higher reimbursement rate compared with LQ hospitals when a major complication did not occur (p = 0.002). Mean unadjusted Medicare payment was lower at HQ hospitals by $5,165 per patient vs LQ hospitals (p < 0.001), largely because HQ hospitals had a lower overall incidence of major complications (n = 315 vs n = 625). By having 310 fewer patients with a major complication, HQ hospitals collectively achieved $3.1 million/year in Medicare savings.

CONCLUSIONS

High-quality hospitals are able to achieve substantial Medicare savings by avoiding major complications. Occurrence of major complications was associated with lower Medicare reimbursement rates at both HQ and LQ hospitals vs when no complications occurred.

Nomogram predicting the risk of recurrence after curative-intent resection of primary non-metastatic gastrointestinal neuroendocrine tumors: An analysis of the U.S. Neuroendocrine Tumor Study Group

BACKGROUND

The risk of recurrence after resection of non-metastatic gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) is poorly defined. We developed/validated a nomogram to predict risk of recurrence after curative-intent resection.

METHODS

A training set to develop the nomogram and test set for validation were identified. The predictive ability of the nomogram was assessed using c-indices.

RESULTS

Among 1477 patients, 673 (46%) were included in the training set and 804 (54%) in y the test set. On multivariable analysis, Ki-67, tumor size, nodal status, and invasion of adjacent organs were independent predictors of DFS. The risk of death increased by 8% for each percentage increase in the Ki-67 index (HR 1.08, 95% CI, 1.05-1.10; P < 0.001). GEP-NET invading adjacent organs had a HR of 1.65 (95% CI, 1.03-2.65; P = 0.038), similar to tumors ≥3 cm (HR 1.67, 95% CI, 1.11-2.51; P = 0.014). Patients with 1-3 positive nodes and patients with >3 positive nodes had a HR of 1.81 (95% CI, 1.12-2.87; P = 0.014) and 2.51 (95% CI, 1.50-4.24; P < 0.001), respectively. The nomogram demonstrated good ability to predict risk of recurrence (c-index: training set, 0.739; test set, 0.718).

CONCLUSION

The nomogram was able to predict the risk of recurrence and can be easily applied in the clinical setting.

Impact of histological subtype on the prognosis of patients undergoing surgery for colon cancer

BACKGROUND

The effect of the histological subtype on the prognosis of patients undergoing surgery for colon cancer (CC) is not completely understood.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) 2004-2014 database was used to compare the long-term outcomes of patients undergoing colon resection for classical adenocarcinoma (CA), mucinous adenocarcinoma (MUC), and signet-cell adenocarcinoma (SC).

RESULTS

A total of 153 317 (89%) patients had CA, 16 660 (10%) MUC while 1810 (1%) patients had SC subtype. Patients with MUC and SC more frequently had a poorly differentiated CC and were more likely to present with advanced disease compared with CA patients (P < 0.001). Patients with CA had a 5-year OS of 62% versus 55% and 34% for patients with MUC and SC subtypes, respectively (P = 0.001). On multivariable analysis, site of cancer, tumor grade, and TNM stage were associated with prognosis (all P < 0.001). After controlling for these risk factors, patients with MUC (HR, 1.09, P < 0.001) and SC (HR, 1.47, P < 0.001) had a roughly 10% and 50% increased hazard of death, respectively, compared with CA patients.

CONCLUSIONS

MUC and SC are distinct subtypes of CC associated with a worse prognosis. These data can help inform discussion about prognosis and possibly direct adjuvant management.

Safety and oncologic outcomes of robotic liver resections: A systematic review

The robotic system has emerged as a new minimally invasive technology with promising results. We sought to systematically review the available literature on the safety and the oncologic outcomes of robotic liver surgery. A systematic review was conducted using Medline (PubMed), Embase and Cochrane library through November 12th, 2017. A robotic approach may be a safe and feasible surgical option for minor and major liver resections.

Neuroendocrine liver metastasis: The chance to be cured after liver surgery

BACKGROUND AND OBJECTIVE

Neuroendocrine liver metastasis tumors (NELM) are a heterogeneous group of neoplasms with varied histologic features and a wide range of clinical behaviors. We aimed to identify the fraction of patients cured after liver surgery for NELM.

METHODS

Cure fraction models were used to analyze 376 patients who underwent hepatectomy with curative intent for NELM.

RESULTS

The median and 5-year disease-free survival (DFS) were 4.5 years and 46%, respectively. The probability of being cured from NELM by liver surgery was 44%; the time to cure was 5.1 years. In a multivariable cure model, type of neuroendocrine tumor (NET), grade of tumor differentiation, and rate of liver involvement resulted as independent predictors of cure. The cure fraction for patients with well differentiated NELM from gastrointestinal NET or a functional pancreatic NET, and with <50% of liver-involvement was 95%. Patients who had moderately/poorly differentiated NELM from a non-functional pancreatic NET, and with <50% of liver-involvement was 43%. In the presence of all the three unfavorable prognostic factors (nonfunctional PNET, liver involvement >50%, moderately/poorly differentiation), the cure fraction was 8%.

CONCLUSIONS

Statistical cure after surgery for NELM is possible, and allow for a more accurate prediction of long-term outcome among patients with NELM undergoing liver resection.

KRAS Mutation Status Dictates Optimal Surgical Margin Width in Patients Undergoing Resection of Colorectal Liver Metastases

BACKGROUND

The optimal tumor-free margin width remains controversial and may be inappropriate to investigate without considering differences in the underlying tumor biology.

METHODS

R1 resection was defined as margin clearance less than 1 mm. R0 resection was further divided into 3 groups: 1-4, 5-9, and ≥10 mm. The impact of margin width on overall survival (OS) relative to KRAS status [wild type (wtKRAS) vs. mutated (mutKRAS)] was assessed.

RESULTS

A total of 411 patients met inclusion criteria. Median patient age was 58 years (interquartile range, 49.7-66.7); most patients were male (n = 250; 60.8 %). With a median follow-up of 28.3 months, median and 5-year OS were 69.8 months and 55.1 %. Among patients with wtKRAS tumors, although margin clearance of 1-4 mm or more was associated with improved OS compared to R1 (all P < 0.05), no difference in OS was observed when comparing margin clearance of 1-4 mm to the 5-9 mm and the ≥10 mm groups (all P > 0.05). In contrast, among patients with mutKRAS tumors, all three groups of margin clearance (1-4, 5-9, and ≥10 mm) fared no better in terms of 5-year survival compared to R1 resection (all P > 0.05).

CONCLUSIONS

While a 1-4 mm margin clearance in patients with wtKRAS tumors was associated with improved survival, wider resection width did not confer an additional survival benefit. In contrast, margin status-including a 1 cm margin-did not improve survival among patients with mutKRAS tumors.