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Hepatocellular adenomas (HCAs) are benign liver tumors associated with bleeding or malignant transformation. Data on the indication for surgery are scarce. We analyzed indications and outcome of patients operated for HCAs < 50mm compared to HCAs = 50 mm. Changes in final postoperative diagnosis were assessed. We performed a retrospective study that included patients who underwent resection for (suspected) HCAs in the Netherlands from 2014 to 2019. Indication for resection was analyzed and stratified for small (<50 mm) and large (=50 mm) tumors. Logistic regression analysis was performed on factors influencing change in tumor diagnosis. Out of 222 patients who underwent surgery, 44 (20%) patients had a tumor <50 mm. Median age was 46 (interquartile range [IQR], 33-56) years in patients with small tumors and 37 (IQR, 31-46) years in patients with large tumors (p = 0.016). Patients with small tumors were more frequently men (21% vs. 5%, p = 0.002). Main indications for resection in patients with small tumors were suspicion of (pre) malignancy (55%), (previous) bleeding (14%), and male sex (11%). Patients with large tumors received operations because of tumor size >50mm (52%), suspicion of (pre)malignancy (28%), and (previous) bleeding (5.1%). No difference was observed in HCA-subtype distribution between small and large tumors. Ninety-six (43%) patients had a postoperative change in diagnosis. Independent risk factors for change in diagnosis were tumor size <50mm (adjusted odds ratio [aOR], 3.4; p < 0.01), male sex (aOR, 3.7; p = 0.03), and lack of hepatobiliary contrast-enhanced magnetic resonance imaging (CE-MRI) (aOR, 1.8; p = 0.04). Resection for small (suspected) HCAs was mainly indicated by suspicion of (pre)malignancy, whereas for large (suspected) HCAs, tumor size was the most prevalent indication. Male sex, tumor size <50 mm, and lack of hepatobiliary CE-MRI were independent risk factors for postoperative change in tumor diagnosis. [ABSTRACT FROM AUTHOR]

BACKGROUND : Nonmodifiable patient and endoscopy characteristics might influence colonoscopy performance. Differences in these so-called case-mix factors are likely to exist between endoscopy centers. This study aimed to examine the importance of case-mix adjustment when comparing performance between endoscopy centers. METHODS : Prospectively collected data recorded in the Dutch national colonoscopy registry between 2016 and 2019 were retrospectively analyzed. Cecal intubation rate (CIR) and adequate bowel preparation rate (ABPR) were analyzed. Additionally, polyp detection rate (PDR) was studied in screening colonoscopies following a positive fecal immunochemical test (FIT). Variation in case-mix factors between endoscopy centers and expected outcomes for each performance measure were calculated per endoscopy center based on case-mix factors (sex, age, American Society of Anesthesiologist [ASA] score, indication) using multivariable logistic regression. RESULTS:  363 840 colonoscopies were included from 51 endoscopy centers. Mean percentages per endoscopy center were significantly different for age > 65 years, male patients, ASA ≥ III, and diagnostic colonoscopies (all P < 0.001). In the FIT-positive screening population, significant differences were observed between endoscopy centers for age > 65 years, male patients, and ASA ≥ III (all P ≤ 0.001). The expected CIR, ABPR, and PDR ranged from 95.0 % to 96.9 %, from 93.6 % to 96.4 %, and from 76.2 % to 79.1 %, respectively. Age, sex, ASA classification, and indication were significant case-mix factors for CIR and ABPR. In the FIT-positive screening population, age, sex, and ASA classification were significant case-mix factors for PDR. CONCLUSION:  Our findings emphasize the importance of considering case-mix adjustment when comparing colonoscopy performance measures between endoscopy centers. [ABSTRACT FROM AUTHOR]

Background: In colorectal liver metastases (CRLM) patients, combination of liver resection and ablation permit a more parenchymal-sparing approach. This study assessed trends in use of combined resection and ablation, outcomes, and overall survival (OS)., Methods: This population-based study included all CRLM patients who underwent liver resection between 2014 and 2022. To assess OS, data was linked to two databases containing date of death for patients treated between 2014 and 2018. Hospital variation in the use of combined minor liver resection and ablation versus major liver resection alone in patients with 2-3 CRLM and ≤3 cm was assessed. Propensity score matching (PSM) was applied to evaluate outcomes., Results: This study included 3593 patients, of whom 1336 (37.2%) underwent combined resection and ablation. Combined resection increased from 31.7% in 2014 to 47.9% in 2022. Significant hospital variation (range 5.9-53.8%) was observed in the use of combined minor liver resection and ablation. PSM resulted in 1005 patients in each group. Major morbidity was not different (11.6% vs. 5%, P = 1.00). Liver failure occurred less often after combined resection and ablation (1.9% vs. 0.6%, P = 0.017). Five-year OS rates were not different (39.3% vs. 33.9%, P = 0.145)., Conclusion: Combined resection and ablation should be available and considered as an alternative to resection alone in any patient with multiple metastases., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Introduction: Routine treatment with preoperative systemic chemotherapy (CTx) in patients with colorectal liver metastases (CRLM) remains controversial due to lack of consistent evidence demonstrating associated survival benefits. This study aimed to determine the effect of preoperative CTx on overall survival (OS) compared to surgery alone and to assess hospital and oncological network variation in 5-year OS., Methods: This was a population-based study of all patients who underwent liver resection for CRLM between 2014 and 2017 in the Netherlands. After 1:1 propensity score matching (PSM), OS was compared between patients treated with and without preoperative CTx. Hospital and oncological network variation in 5-year OS corrected for case-mix factors was calculated using an observed/expected ratio., Results: Of 2820 patients included, 852 (30.2%) and 1968 (69.8%) patients were treated with preoperative CTx and surgery alone, respectively. After PSM, 537 patients remained in each group, median number of CRLM; 3 [IQR 2-4], median size of CRLM; 28 mm [IQR 18-44], synchronous CLRM (71.1%). Median follow-up was 80.8 months. Five-year OS rates after PSM for patients treated with and without preoperative chemotherapy were 40.2% versus 38.3% (log-rank P = 0.734). After stratification for low, medium, and high tumour burden based on the tumour burden score (TBS) OS was similar for preoperative chemotherapy vs. surgery alone (log-rank P = 0.486, P = 0.914, and P = 0.744, respectively). After correction for non-modifiable patient and tumour characteristics, no relevant hospital or oncological network variation in five-year OS was observed., Conclusion: In patients eligible for surgical resection, preoperative chemotherapy does not provide an overall survival benefit compared to surgery alone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Textbook outcome (TO) is a composite outcome measure covering the surgical care process in a single outcome measure. TO has an advantage over single outcome parameters with low event rates, which have less discriminating impact to detect differences between hospitals. This study aimed to assess factors associated with TO, and evaluate hospital and network variation after case-mix correction in TO rates for liver surgery., Methods: This was a population-based retrospective study of all patients who underwent liver resection for malignancy in the Netherlands in 2019 and 2020. TO was defined as absence of severe postoperative complications, mortality, prolonged length of hospital stay, and readmission, and obtaining adequate resection margins. Multivariable logistic regression was used for case-mix adjustment., Results: 2376 patients were included. TO was accomplished in 1380 (80%) patients with colorectal liver metastases, in 192 (76%) patients with other liver metastases, in 183 (74%) patients with hepatocellular carcinoma and 86 (51%) patients with biliary cancers. Factors associated with lower TO rates for CRLM included ASA score ≥3 (aOR 0.70, CI 0.51-0.95 p = 0.02), extrahepatic disease (aOR 0.64, CI 0.44-0.95, p = 0.02), tumour size >55 mm on preoperative imaging (aOR 0.56, CI 0.34-0.94, p = 0.02), Charlson Comorbidity Index ≥2 (aOR 0.73, CI 0.54-0.98, p = 0.04), and major liver resection (aOR 0.50, CI 0.36-0.69, p < 0.001). After case-mix correction, no significant hospital or oncological network variation was observed., Conclusion: TO differs between indications for liver resection and can be used to assess between hospital and network differences., Competing Interests: Declaration of competing interest All authors declare no conflict of interest., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Hepatocellular adenomas (HCAs) are benign liver tumors associated with bleeding or malignant transformation. Data on the indication for surgery are scarce. We analyzed indications and outcome of patients operated for HCAs < 50 mm compared to HCAs ≥ 50 mm. Changes in final postoperative diagnosis were assessed. We performed a retrospective study that included patients who underwent resection for (suspected) HCAs in the Netherlands from 2014 to 2019. Indication for resection was analyzed and stratified for small (<50 mm) and large (≥50 mm) tumors. Logistic regression analysis was performed on factors influencing change in tumor diagnosis. Out of 222 patients who underwent surgery, 44 (20%) patients had a tumor <50 mm. Median age was 46 (interquartile range [IQR], 33-56) years in patients with small tumors and 37 (IQR, 31-46) years in patients with large tumors ( p  = 0.016). Patients with small tumors were more frequently men (21% vs. 5%, p  = 0.002). Main indications for resection in patients with small tumors were suspicion of (pre)malignancy (55%), (previous) bleeding (14%), and male sex (11%). Patients with large tumors received operations because of tumor size >50 mm (52%), suspicion of (pre)malignancy (28%), and (previous) bleeding (5.1%). No difference was observed in HCA-subtype distribution between small and large tumors. Ninety-six (43%) patients had a postoperative change in diagnosis. Independent risk factors for change in diagnosis were tumor size <50 mm (adjusted odds ratio [aOR], 3.4; p  < 0.01), male sex (aOR, 3.7; p  = 0.03), and lack of hepatobiliary contrast-enhanced magnetic resonance imaging (CE-MRI) (aOR, 1.8; p  = 0.04). Resection for small (suspected) HCAs was mainly indicated by suspicion of (pre)malignancy, whereas for large (suspected) HCAs, tumor size was the most prevalent indication. Male sex, tumor size <50 mm, and lack of hepatobiliary CE-MRI were independent risk factors for postoperative change in tumor diagnosis., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc on behalf of the American Association for the Study of Liver Diseases.)

Existing literature suggests inferior quality of oncologic surgery during holiday periods. This study aimed to investigate the impact of holiday periods on surgical treatment of gastric cancer in the Netherlands. This nationwide study included all gastric cancer patients undergoing potentially curative surgery registered in the Dutch Upper Gastrointestinal Cancer Audit (DUCA). For each patient it was established whether they underwent surgery during or outside the 11 Dutch holiday weeks, based on date and region of surgery. Separate, single-day holidays were not included. Baseline and treatment characteristics were compared using descriptive statistics. Time from diagnosis to treatment and short-term surgical outcomes were compared using multilevel multivariable logistic regression analyses. To prevent bias from recent advancements, analyses were repeated in a recent cohort of patients (2015-2018). Between 2011-2018, 3440 patients were included in the DUCA. Some 555 (16.1%) patients underwent surgery during 11 holiday weeks. There were no differences in patient, tumor and treatment characteristics and time to treatment between holidays and non-holidays. Tumor-positive resection margins (R1/R2 vs R0) occurred more frequent during holidays (aOR:1.47, 95%CI:1.07-2.04). Subgroup analyses in a recent cohort of patients also found higher tumor-positive resection margins (aOR:1.59, 95%CI:1.01-2.43) and higher failure-to-rescue rates (aOR:2.55, 95%CI:1.18-5.49) during holidays. Even though time to treatment and patient, tumor and treatment characteristics were comparable between holidays and non-holidays, tumor-positive resection margin and failure-to-rescue rates were higher during holidays. This suggests that steps must be taken to keep specialized and dedicated gastric cancer expertise up to standard during holiday periods., (Copyright © 2022. Published by Elsevier Inc.)

Background: The optimal treatment sequence for patients with synchronous colorectal liver metastases (CRLM) remains uncertain. This study aimed to assess factors associated with the use of simultaneous resections and impact on hospital variation., Method: This population-based study included all patients who underwent liver surgery for synchronous colorectal liver metastases between 2014 and 2019 in the Netherlands. Factors associated with simultaneous resection were identified. Short-term surgical outcomes of simultaneous resections and factors associated with 30-day major morbidity were evaluated., Results: Of 2146 patients included, 589 (27%) underwent simultaneous resection in 28 hospitals. Simultaneous resection was associated with age, sex, BMI, number, size and bilobar distribution of CRLM, and administration of preoperative chemotherapy. More minimally invasive and minor resections were performed in the simultaneous group. Hospital variation was present (range 2.4%-83.3%) with several hospitals performing simultaneous procedures more and less frequently than expected. Simultaneous resection resulted in 13% 30-day major morbidity, and 1% mortality. ASA classification ≥3 was independently associated with higher 30-day major morbidity after simultaneous resection (aOR 1.97, CI 1.10-3.42, p = 0.018)., Conclusion: Distinctive patient and tumour characteristics influence the choice for simultaneous resection. Remarkable hospital variation is present in the Netherlands., (Copyright © 2021 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Introduction: Widespread differences in patient demographics and disease burden between hospitals for resection of colorectal liver metastases (CRLM) have been described. In the Netherlands, networks consisting of at least one tertiary referral centre and several regional hospitals have been established to optimize treatment and outcomes. The aim of this study was to assess variation in case-mix, and outcomes between these networks., Methods: This was a population-based study including all patients who underwent CRLM resection in the Netherlands between 2014 and 2019. Variation in case-mix and outcomes between seven networks covering the whole country was evaluated. Differences in case-mix, expected 30-day major morbidity (Clavien-Dindo ≥3a) and 30-day mortality between networks were assessed., Results: In total 5383 patients were included. Thirty-day major morbidity was 5.7% and 30-day mortality was 1.5%. Significant differences between networks were observed for Charlson Comorbidity Index, ASA 3+, previous liver resection, liver disease, preoperative MRI, preoperative chemotherapy, ≥3 CRLM, diameter of largest CRLM ≥55 mm, major resection, combined resection and ablation, rectal primary tumour, bilobar and extrahepatic disease. Uncorrected 30-day major morbidity ranged between 3.3% and 13.1% for hospitals, 30-day mortality ranged between 0.0% and 4.5%. Uncorrected 30-day major morbidity ranged between 4.4% and 6.0% for networks, 30-day mortality ranged between 0.0% and 2.5%. No negative outliers were observed after case-mix correction., Conclusion: Variation in case-mix and outcomes are considerably smaller on a network level as compared to a hospital level. Therefore, auditing is more meaningful at a network level and collaboration of hospitals within networks should be pursued., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Failure to rescue (FTR) is defined as postoperative complications leading to mortality. This nationwide study aimed to assess factors associated with FTR and hospital variation in FTR after liver surgery., Methods: All patients who underwent liver resection between 2014 and 2017 in the Netherlands were included. FTR was defined as in-hospital or 30-day mortality after complications Dindo grade ≥3a. Variables associated with FTR and nationwide hospital variation were assessed using multivariable logistic regression., Results: Of 4961 patients included, 3707 (74.4%) underwent liver resection for colorectal liver metastases, 379 (7.6%) for other metastases, 526 (10.6%) for hepatocellular carcinoma and 349 (7.0%) for biliary cancer. Thirty-day major morbidity was 11.5%. Overall mortality was 2.3%. FTR was 19.1%. Age 65-80 (aOR: 2.86, CI:1.01-12.0, p = 0.049), ASA 3+ (aOR:2.59, CI: 1.66-4.02, p < 0.001), liver cirrhosis (aOR:4.15, CI:1.81-9.22, p < 0.001), biliary cancer (aOR:3.47, CI: 1.73-6.96, p < 0.001), and major resection (aOR:6.46, CI: 3.91-10.9, p < 0.001) were associated with FTR. Postoperative liver failure (aOR: 26.9, CI: 14.6-51.2, p < 0.001), cardiac (aOR: 2.62, CI: 1.27-5.29, p = 0.008) and thromboembolic complications (aOR: 2.49, CI: 1.16-5.22, p = 0.017) were associated with FTR. After case-mix correction, no hospital variation in FTR was observed., Conclusion: FTR is influenced by patient demographics, disease and procedural burden. Prevention of postoperative liver failure, cardiac and thromboembolic complications could decrease FTR., Competing Interests: Declaration of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Liver resection is high-risk surgery in particular in elderly patients. The aim of this study was to explore postoperative outcomes after liver resection in elderly patients., Methods: In this nationwide study, all patients who underwent liver resection for primary and secondary liver tumours in the Netherlands between 2014 and 2019 were included. Age groups were composed as younger than 70 (70-), between 70 and 80 (septuagenarians), and 80 years or older (octogenarians). Proportion of liver resections per age group and 30-day major morbidity and 30-day mortality were assessed., Results: In total, 6587 patients were included of whom 4023 (58.9%) were younger than 70, 2135 (32.4%) were septuagenarians and 429 (6.5%) were octogenarians. The proportion of septuagenarians increased during the study period (aOR:1.06, CI:1.02-1.09, p < 0.001). Thirty-day major morbidity was higher in septuagenarians (11%) and octogenarians (12%) compared to younger patients (9%, p = 0.049). Thirty-day mortality was higher in septuagenarians (4%) and octogenarians (4%) compared to younger patients (2%, p < 0.001). Cardiopulmonary complications occurred more frequently with higher age, liver-specific complications did not. Higher age was associated with higher 30-day morbidity and 30-day mortality in multivariable logistic regression., Conclusion: Thirty-day major morbidity and 30-day mortality are higher after liver resection in elderly patients, attributed mainly to non-surgical cardiopulmonary complications., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Data on surgical outcomes of laparoscopic liver resection (LLR) versus open liver resection (OLR) of benign liver tumour (BLT) are scarce. This study aimed to provide a nationwide overview of postoperative outcomes after LLR and OLR of BLT., Methods: This was a nationwide retrospective study including all patients who underwent liver resection for hepatocellular adenoma, haemangioma and focal nodular hyperplasia in the Netherlands from 2014 to 2019. Propensity score matching (PSM) was applied to compare 30-day overall and major morbidity and 30-day mortality after OLR and LLR., Results: In total, 415 patients underwent BLT resection of whom 230 (55.4%) underwent LLR. PSM for OLR and LLR resulted in 250 matched patients. Median (IQR) length of stay was shorter after LLR than OLR (4 versus 6 days, 5.0-8.0, p < 0.001). Postoperative 30-day overall morbidity was lower after LLR than OLR (12.0% vs. 22.4%, p = 0.043). LLR was associated with reduced 30-day overall morbidity in multivariable analysis (aOR:0.46, CI:0.22-0.95, p = 0.043). Both 30-day major morbidity and 30-day mortality were not different., Conclusions: LLR for BLT is associated with shorter hospital stay and reduced overall morbidity and is preferred if technically feasible., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Combining resection and thermal ablation can improve short-term postoperative outcomes in patients with colorectal liver metastases (CRLM). This study assessed nationwide hospital variation and short-term postoperative outcomes after combined resection and ablation., Methods: In this population-based study, all CRLM patients who underwent resection in the Netherlands between 2014 and 2018 were included. After propensity score matching for age, ASA-score, Charlson-score, diameter of largest CRLM, number of CRLM and earlier resection, postoperative outcomes were compared. Postoperative complicated course (PCC) was defined as discharge after 14 days or a major complication or death within 30 days of surgery., Results: Of 4639 included patients, 3697 (80%) underwent resection and 942 (20%) resection and ablation. Unadjusted percentage of patients who underwent resection and ablation per hospital ranged between 4 and 44%. Hospital variation persisted after case-mix correction. After matching, 734 patients remained in each group. Hospital stay (median 6 vs. 7 days, p = 0.011), PCC (11% vs. 14.7%, p = 0.043) and 30-day mortality (0.7% vs. 2.3%, p = 0.018) were lower in the resection and ablation group. Differences faded in multivariable logistic regression due to inclusion of major hepatectomy., Conclusion: Significant hospital variation was observed in the Netherlands. Short-term postoperative outcomes were better after combined resection and ablation, attributed to avoiding complications associated with major hepatectomy., (Copyright © 2020 University Medical Center Groningen. Published by Elsevier Ltd.. All rights reserved.)

Background: Differences in patient demographics and disease burden can influence comparison of hospital performances. This study aimed to provide a case-mix model to compare short-term postoperative outcomes for patients undergoing liver resection for colorectal liver metastases (CRLM)., Methods: This retrospective, population-based study included all patients who underwent liver resection for CRLM between 2014 and 2018 in the Netherlands. Variation in case-mix variables between hospitals and influence on postoperative outcomes was assessed using multivariable logistic regression. Primary outcomes were 30-day major morbidity and 30-day mortality. Validation of results was performed on the data from 2019., Results: In total, 4639 patients were included in 28 hospitals. Major morbidity was 6.2% and mortality was 1.4%. Uncorrected major morbidity ranged from 3.3% to 13.7% and mortality ranged from 0.0% to 5.0%. between hospitals. Significant differences between hospitals were observed for age higher than 80 (0.0%-17.1%, p < 0.001), ASA 3 or higher (3.3%-36.3%, p < 0.001), histopathological parenchymal liver disease (0.0%-47.1%, p < 0.001), history of liver resection (8.1%-36.3%, p < 0.001), major liver resection (6.7%-38.0%, p < 0.001) and synchronous metastases (35.5%-62.1%, p < 0.001). Expected 30-day major morbidity between hospitals ranged from 6.4% to 11.9% and expected 30-day mortality ranged from 0.6% to 2.9%. After case-mix correction no significant outliers concerning major morbidity and mortality remained. Validation on patients who underwent liver resection for CRLM in 2019 affirmed these outcomes., Conclusion: Case-mix adjustment is a prerequisite to allow for institutional comparison of short-term postoperative outcomes after liver resection for CRLM., Competing Interests: Declaration of conpeting interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 University Medical Center Groningen. Published by Elsevier Ltd.. All rights reserved.)

Introduction: Definitions regarding resectability and hence indications for preoperative chemotherapy vary. Use of preoperative chemotherapy may influence postoperative outcomes. This study aimed to assess the variation in use of preoperative chemotherapy for CRLM and related postoperative outcomes in the Netherlands., Materials and Methods: All patients who underwent liver resection for CRLM in the Netherlands between 2014 and 2018 were included from a national database. Case-mix factors contributing to the use of preoperative chemotherapy, hospital variation and postoperative outcomes were assessed using multivariable logistic regression. Postoperative outcomes were postoperative complicated course (PCC), 30-day morbidity and 30-day mortality., Results: In total, 4469 patients were included of whom 1314 patients received preoperative chemotherapy and 3155 patients did not. Patients receiving chemotherapy were significantly younger (mean age (+SD) 66.3 (10.4) versus 63.2 (10.2) p < 0.001) and had less comorbidity (Charlson scores 2+ (24% versus 29%, p = 0.010). Unadjusted hospital variation concerning administration of preoperative chemotherapy ranged between 2% and 55%. After adjusting for case-mix factors, three hospitals administered significantly more preoperative chemotherapy than expected and six administered significantly less preoperative chemotherapy than expected. PCC was 12.1%, 30-day morbidity was 8.8% and 30-day mortality was 1.5%. No association between preoperative chemotherapy and PCC (OR 1.24, 0.98-1.55, p = 0.065), 30-day morbidity (OR 1.05, 0.81-1.39, p = 0.703) or with 30-day mortality (OR 1.22, 0.75-2.09, p = 0.467) was found., Conclusion: Significant hospital variation in the use of preoperative chemotherapy for CRLM was present in the Netherlands. No association between postoperative outcomes and use of preoperative chemotherapy was found., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)