Background: Undifferentiated pleomorphic sarcoma (UPS) is a relatively rare but aggressive neoplasm. We sought to utilize a multi-institutional US cohort of sarcoma patients to examine predictors of survival and recurrence patterns after resection of UPS. Methods: From 2000 to 2016, patients with primary UPS undergoing curative-intent surgical resection at seven academic institutions were retrospectively reviewed. Epidemiologic and clinicopathologic factors were reviewed by site of origin. Overall survival (OS), recurrence-free survival (RFS), time-to-locoregional (TTLR), time-to-distant recurrence (TTDR), and patterns of recurrence were analyzed. Results: Of the 534 UPS patients identified, 53% were female, with a median age of 60 and median tumor size of 8.5 cm. The median OS, RFS, TTLR, and TTDR for the entire cohort were 109, 49, 86, and 46 months, respectively. There were no differences in these survival outcomes between extremity and truncal UPS. Compared with truncal, extremity UPS were more commonly amenable to R0 resection (87% vs. 75%, p = 0.017) and less commonly associated with lymph node metastasis (1% vs. 6%, p = 0.031). R0 resection and radiation treatment, but not site of origin (extremity vs. trunk) were independent predictors of OS and RFS. TTLR recurrence was shorter for UPS resected with a positive margin and for tumors not treated with radiation. Conclusion: For patients with resected extremity and truncal UPS, tumor size >5 cm and positive resection margin are associated with worse survival OS and RFS, irrespectively the site of origin. R0 surgical resection and radiation treatment may help improve these survival outcomes.

Abstract Background: Sentinel lymph node (SLNB) biopsy for axillary staging in patients (pts) with ductal carcinoma in situ (DCIS) undergoing mastectomy is debated due to low positivity rate and potential morbidity. Standard SLNB entails removing all LNs with a radioactive count >10% of the most radioactive node, contain blue dye or are palpably suspicious. In this study, we hypothesize that judicious SLNB with attempt to remove only the SLN with the highest radioactive count provides sufficient pathologic information while minimizing morbidity. Method: A single institution prospective database was retrospectively reviewed to identify women with core biopsy showing DCIS (cTis) who underwent mastectomy and SLNB between 2010–22. Pt characteristics, number of SLNs retrieved, pathologic results and long-term upper extremity complications were collected. Results: A total of 743 LN's were removed in 324 pts. Median [IQR] age was 62 [51–70] years. Dual tracer technique, with Technetium-99m labeled radiocolloid and blue dye, was used in 311 (96%) pts, whereas single agent (radioisotope or blue dye alone) was utilized in 9 (2.8%) and 4 (1.2%) pts respectively. Median [IQR] number of SLN removed was 2 [1-3] (range 1-9). In 99% of cases, the SLN with the highest radioactive count was identified among the first 3 dissected LNs. Final pathology revealed upstaging to invasive cancer in 27.5% (n=89) of the breasts and nodal positivity in 1.9% (n=6) of the patients. In all 6 cases, metastatic disease was identified in the LN with highest radioactive count among the LNs retrieved. No additional metastatic nodes were identified after >3 SLN had been removed. At median follow-up of 57 (range 28-87) months, 8.3% (n=27) of pts complained of long-term upper extremity symptoms. 7.1% (23 pts) were referred to physical therapy for symptoms such as swelling, fullness, heaviness, stiffness or sensory discomfort in the upper extremity and/or axillary cording. Long-term upper extremity complications were higher when >3 SLNs compared to <3 SLNs were removed (10.4% vs 6.5%, p=0.005). Conclusion: In this cohort of pts with DCIS (cTis) undergoing mastectomy who had upstaging on final pathology to invasive cancer with LN involvement, the SLN with the highest radioactive count provided sufficient information for axillary staging. Acknowledging that the “hottest” LN is not always the first one removed, these data support an increased likelihood of developing long-term complications when more than three SLNs are removed. Rather than comprehensive removal of all SLNs meeting the standard “10% rule,” prioritizing the sequence of removal to the highest count provides the same prognostic information with reduced morbidity. Patient and lymph node characteristics Citation Format: Adil Ayub, Kazim Senol, Makris Eleftherios, Michael Cowher, Ronald Johnson, Kristin Lupinacci, Qurat Ul Ain Sabih, Jennifer Steiman, Emilia Diego, Priscilla McAuliffe, Atilla Soran. De-Escalating Extent of Sentinel Lymph Node Biopsy in Patients with Ductal Carcinoma in Situ Undergoing Mastectomy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-12-09.

Sentinel lymph node biopsy (SLNB) in patients with ductal carcinoma in situ (DCIS) is debated. In this single- institutional study, we investigated the patterns of SLN removal and related complications in 324 women with DCIS who underwent mastectomy and SLNB. Nodal positivity was observed in 1.9% ( n = 6) of the patients. In all 6 cases, metastatic disease was identified in the LN with highest radioactive count and no additional metastatic nodes were identified after > 3 SLN had been removed. On follow-up, long-term upper extremity complications were higher when > 3 SLNs compared to <= 3 SLNs were removed (10.4% vs. 6.5%, P = .005). We conclude that in patients with DCIS, the SLN with the highest radioactive count provides sufficient information for axillary staging. Rather than comprehensive removal of all SLNs meeting the standard "10% rule," prioritizing the sequence of removal to the highest count provides the same prognostic information with reduced morbidity. Background: Sentinel lymph node biopsy (SLNB) for axillary staging in patients with ductal carcinoma in situ (DCIS) undergoing mastectomy is debated due to low nodal positivity rate and risk of morbidity. Standard SLNB entails removing all lymph nodes (LN) that have a radioactive count > 10% of the most radioactive node, contain blue dye or are palpably suspicious. In this study, we hypothesize that judicious SLNB with attempt to remove only the node with the highest radioactive count provides sufficient pathologic information while minimizing morbidity. Method: A single institution prospective database was retrospectively reviewed to identify women with DCIS who underwent mastectomy and SLNB between 2010 and 2022. Patient characteristics, number of SLNs retrieved, pathologic results and long-term upper extremity complications were analyzed. Results: A total of 743 LNs were removed in 324 pts. Median (IQR) age was 62 (51-70) years. Dual tracer technique, with technetium-99m labeled radiocolloid and blue dye, was used in 311 (96%) pts, whereas single agent (radioisotope or blue dye alone) was utilized in 9 (2.8%) and 4 (1.2%) patients, respectively. Median (IQR) number of SLN removed was 2 (1-3) (range 1-9). In 99% of cases, the SLN with the highest radioactive count was identified among the first 3 dissected LNs. Final pathology revealed upstaging to invasive cancer in 27.5% ( n = 89) of the breasts and nodal positivity in 1.9% ( n = 6) of the patients. In all 6 cases, metastatic disease was identified in the LN with highest radioactive count among the LNs retrieved. No additional metastatic nodes were identified after > 3 SLN had been removed. At median follow-up of 57 (range 28-87) months, 8.3% ( n = 27) of pts complained of long-term upper extremity symptoms. 7.1% (23 pts) were referred to physical therapy for symptoms such as swelling, fullness, heaviness, stiffness, or sensory discomfort in the upper extremity and/or axillary cording. Long-term upper extremity complications were higher when > 3 SLNs compared to <3 SLNs were removed (10.4% vs. 6.5%, P = .005). Conclusion: In this cohort of patients with DCIS undergoing mastectomy who were upstaged on final pathology to node positive invasive cancers, the SLN with the highest radioactive count provided sufficient information for axillary staging. Acknowledging that the "hottest" LN is not always the first 1 removed, these data support an increased likelihood of developing long-term complications when more than 3 SLNs are removed. Rather than comprehensive removal of all SLNs meeting the standard "10% rule," prioritizing the sequence of removal to the highest count provides the same prognostic information with reduced morbidity.

Background: Enhanced recovery after surgery (ERAS) protocols have been used in several surgical specialties to improve patient outcomes, with a consensus from the ERAS Society in the utility of ERAS for patients undergoing breast reconstruction. However, an equivalent protocol for patients not having reconstruction does not exist. In 2018, an institution specific Breast-ERAS (BERAS) protocol was implemented with the goal of optimizing outcomes for patients undergoing a mastectomy without reconstruction (TM). The hypothesis of this study is that the BERAS protocol would result in a decrease in the in-hospital use of opioid pain medications, post-operative anti-emetic use and hospital length of stay (LOS) without affecting the 30-day readmission rate.

Interleukin 10 (IL-10) is an important anti-inflammatory cytokine. To examine its role in virus-induced encephalomyelitis, IL-10-deficient (IL-10 −/−) mice were infected with a neurotropic strain of mouse hepatitis virus (JHMV). JHMV-infected IL-10 −/− mice, compared to IL-4 −/− and syngeneic C57BL/6 mice, exhibited increased morbidity and mortality. Virus was cleared from the CNS of all groups of mice with equal kinetics by day 9 postinfection and the lack of either IL-4 or IL-10 did not alter the distribution of viral antigen, suggesting a lack of correlation between viral replication and the increased clinical disease in IL-10 −/− mice. In moribund IL-10 −/− mice, a moderate increase in mononuclear cell infiltration was correlated with increased expression of tumor necrosis factor-α, interferon-γ, and inducible nitric oxide synthase mRNAs. In the small percentage of IL-10 −/− mice that survived, no differences in either demyelination or inflammation were observed. Together, these results suggest that IL-10 is not required for viral clearance, and although it appears to be one of the mechanisms responsible for inhibiting the extent of inflammation in the CNS during acute JHMV infection, it has little role in the eventual resolution of CNS inflammatory responses.

GI stromal tumor (GIST) is the most common sarcoma andmesenchymal tumor of the GI tract. These tumors are often characterized according to their location and molecular aberrations. The majority of GIST occur in the stomach (62%) and harbor constitutively activated mutant isoforms of either KIT (75%-85%) or platelet-derived growth factor receptor alpha (PDGFRA; approximately 5%), both of which are type III receptor tyrosine kinases. Other genetic abnormalities associated with GIST include mutations of RAS pathway components (KRAS [2%-5%], BRAF [2%-4%], or NF1 [1.5%-10% depending on the study]) and loss of function in the succinate dehydrogenase protein complex (5%-10%). Rarer molecular alterations include FGFR1 and ETV6-NTRK3 gene fusions. Improved understanding of the molecular aberrancies underlying GIST has served as the foundation for the paradigm shift toward precision oncology, highlighting the importance of molecularly matching driver mutations with cognate agents. For example, the development of tyrosine kinase inhibitors such as imatinib has revolutionized the treatment of KIT mutant GIST and drastically improved survival for patients suffering from this malignancy.

Background: Identifying patients at risk for early recurrence (ER) following resection for pancreatic neuroendocrine tumors (pNETs) might help to tailor adjuvant therapies and surveillance intensity in the post-operative setting. Methods: Patients undergoing surgical resection for pNETs between 1998–2018 were identified using a multi-institutional database. Using a minimum p-value approach, optimal cut-off value of recurrence-free survival (RFS) was determined based on the difference in post-recurrence survival (PRS). Risk factors for early recurrence were identified. Results: Among 807 patients who underwent curative-intent resection for pNETs, the optimal length of RFS to define ER was identified at 18 months (lowest p-value of 0.019). Median RFS was 11.0 months (95% 8.5–12.60) among ER patients (n = 49) versus 41.0 months (95% CI: 35.0–45.9) among non-ER patients (n = 77). Median PRS was worse among ER patients compared with non-ER patients (42.6 months vs. 81.5 months, p = 0.04). On multivariable analysis, tumor size (OR: 1.20, 95% CI: 1.05–1.37, p = 0.007) and positive lymph nodes (OR: 4.69, 95% CI: 1.41–15.58, p = 0.01) were independently associated with ER. Conclusion: An evidence-based cut-off value for ER after surgery for pNET was defined at 18 months. These data emphasized the importance of close follow-up in the first two years after surgery.

BACKGROUND:Surgical resection of hepatic metastases remains the only potentially curative treatment option for patients with colorectal liver metastases (CRLM). Widely adopted prognostic tools may oversimplify the impact of model parameters relative to long-term outcomes.METHODS:Patients with CRLM who underwent a hepatectomy between 2001 and 2018 were identified in an international, multi-institutional database. Bootstrap resampling methodology used in tandem with multivariable mixed-effects logistic regression analysis was applied to construct a prediction model that was validated and compared with scores proposed by Fong and Vauthey.RESULTS:Among 1406 patients who underwent hepatic resection of CRLM, 842 (59.9%) had recurrence. The full model (based on age, sex, primary tumor location, T stage, receipt of chemotherapy before hepatectomy, lymph node metastases, number of metastatic lesions in the liver, size of the largest hepatic metastases, carcinoembryonic antigen [CEA] level and KRAS status) had good discriminative ability to predict 1-year (area under the receiver operating curve [AUC], 0.693; 95% confidence interval [CI], 0.684-0.704), 3-year (AUC, 0.669; 95% CI, 0.661-0.677), and 5-year (AUC, 0.669; 95% CI, 0.661-0.679) risk of recurrence. Studies analyzing validation cohorts demonstrated similar model performance, with excellent model accuracy. In contrast, the AUCs for the Fong and Vauthey scores to predict 1-year recurrence were only 0.527 (95% CI, 0.514-0.538) and 0.525 (95% CI, 0.514-0.533), respectively. Similar trends were noted for 3- and 5-year recurrence.CONCLUSION:The proposed clinical score, derived via machine learning, which included clinical characteristics and morphologic data, as well as information on KRAS status, accurately predicted recurrence after CRLM resection with good discrimination and prognostic ability.

Background: The adoption of spleen-preserving distal pancreatectomy (SPDP) for malignant disease such as pancreatic neuroendocrine tumors (pNETs) has been controversial. The objective of the current study was to assess the impact of SPDP on outcomes of patients with pNETs. Methods: Patients undergoing a distal pancreatectomy for pNET between 2002 and 2016 were identified in the US Neuroendocrine Tumor Study Group database. Propensity score matching (PSM) was used to compare short- and long-term outcomes of patients undergoing SPDP versus distal pancreatectomy with splenectomy (DPS). Results: Among 621 patients, 103 patients (16.6%) underwent an SPDP. Patients who underwent SPDP were more likely to have lower BMI (median, 27.5 [IQR 24.0–31.2] vs. 28.7 [IQR 25.7–33.6]; p = 0.005) and have undergone minimally invasive surgery (n = 56, 54.4% vs. n = 185, 35.7%; p < 0.001). After PSM, while the median total number of lymph nodes examined among patients who underwent an SPDP was lower compared with DPS (3 [IQR 1–8] vs. 9 [5–13]; p < 0.001), 5-year overall survival (OS) and recurrence-free survival (RFS) were comparable (OS: 96.8 vs. 92.0%, log-rank p = 0.21, RFS: 91.1 vs. 84.7%, log-rank p = 0.93). In addition, patients undergoing SPDP had less intraoperative blood loss (median, 100 mL [IQR 10–250] vs. 150 mL [IQR 100–400]; p = 0.001), lower incidence of serious complications (n = 13, 12.8% vs. n = 28, 27.5%; p = 0.014), and shorter length of stay (median: 5 days [IQR 4–7] vs. 6 days [IQR 5–13]; p = 0.049) compared with patients undergoing DPS. Conclusion: SPDP for pNET was associated with acceptable perioperative and long-term outcomes that were comparable to DPS. SPDP should be considered for patients with pNET.

Pancreatic neuroendocrine tumors (PNETs) are often indolent; however, identifying patients at risk for rapidly progressing variants is critical, particularly for those with small tumors who may be candidates for expectant management. Specific growth rate (SGR) has been predictive of survival in other malignancies but has not been examined in PNETs. A retrospective cohort study of adult patients who underwent PNET resection from 2000 to 2016 was performed utilizing the multi-institutional United States Neuroendocrine Study Group database. Patients with ≥ 2 preoperative cross-sectional imaging studies at least 30 days apart were included in our analysis (N = 288). Patients were grouped as “high SGR” or “low SGR.” Demographic and clinical factors were compared between the groups. Kaplan–Meier and log-rank analysis were used for survival analysis. Cox proportional hazard analysis was used to assess the impact of various clinical factors on overall survival (OS). High SGR was associated with higher T stage at resection, shorter doubling time, and elevated HbA1c (all P ≤ 0.01). Patients with high SGR had significantly decreased 5-year OS (63 vs 80%, P = 0.01) and disease-specific survival (72 vs 91%, P = 0.03) compared to those with low SGR. In patients with small (≤ 2 cm) tumors (N = 106), high SGR predicted lower 5-year OS (79 vs 96%, P = 0.01). On multivariate analysis, high SGR was independently associated with worse OS (hazard ratio 2.67, 95% confidence interval 1.05–6.84, P = 0.04). High SGR is associated with worse survival in PNET patients. Evaluating PNET SGR may enhance clinical decision-making, particularly when weighing expectant management versus surgery in patients with small tumors.

Objective: To improve the prognostic accuracy of the eighth edition of AJCC staging system for pNETs with establishment and validation of a new staging system. Background: Validation of the updated eighth AJCC staging system for pNETs has been limited and controversial. Methods: Data from the SEER registry (1975–2016) (n = 3303) and a multi-institutional database (2000–2016) (n = 825) was used as development and validation cohorts, respectively. A mTNM was proposed by maintaining the eighth AJCC T and M definitions, and the recently proposed N status as N0 (no LNM), N1 (1–3 LNM), and N2 (≥4 LNM), but adopting a new stage classification. Results: The eighth TNM staging system failed to stratify patients with stage I versus IIA, stage IIB versus IIIA, and overall stage I versus II relative to long-term OS in both database. There was a monotonic decrement in survival based on the proposed mTNM staging classification among patients derived from both the SEER (5-year OS, stage I 87.0% vs stage II 80.3% vs stage III 72.9% vs stage IV 57.2%, all P < 0.001), and multi-institutional (5-year OS, stage I 97.6% vs stage II 82.7% vs stage III 78.4% vs stage IV 50.0%, all P < 0.05) datasets. On multivariable analysis, mTNM staging remained strongly associated with prognosis, as the hazard of death incrementally increased with each stage among patients in the 2 cohorts. Conclusion: A mTNM pNETs clinical staging system using N0, N1, N2 nodal categories was better at stratifying patients relative to long-term OS than the eighth AJCC staging.

Background: Pancreatoduodenectomy (PD) or distal pancreatectomy (DP) are common procedures for patients with a pancreatic neuroendocrine tumor (pNET). Nevertheless, certain patients may benefit from a pancreas-preserving resection such as enucleation (EN). The aim of this study was to define the indications and differences in long-term outcomes among patients undergoing EN and PD/DP. Methods: Patients undergoing resection of a pNET between 1992 and 2016 were identified. Indications and outcomes were evaluated, and propensity score matching (PSM) analysis was performed to compare long-term outcomes between patients who underwent EN versus PD/DP. Results: Among 1034 patients, 143 (13.8%) underwent EN, 304 (29.4%) PD, and 587 (56.8%) DP. Indications for EN were small size (1.5 cm, IQR:1.0-1.9), functional tumors (58.0%) that were mainly insulinomas (51.7%). After PSM (n = 109 per group), incidence of postoperative pancreatic fistula (POPF) grade B/C was higher after EN (24.5%) compared with PD/DP (14.0%) (p = 0.049). Median recurrence free survival (RFS) was comparable among patients who underwent EN (47 months, 95% CI:23-71) versus PD/DP (37 months, 95% CI: 33-47, p = 0.480). Conclusion: Comparable long-term outcomes were noted among patients who underwent EN versus PD/DP for pNET. The incidence of clinically significant POPF was higher after EN.

Background and Aims: Colorectal liver metastases (CRLM) develop in 60% of patients diagnosed with colorectal cancer. Surgical resection for CRLM might involve anatomical (AH) or parenchymal-sparing hepatectomies (PSH). Short-term and oncological outcomes of AH and PSH for CRLM patients with multifocal (=4 tumors) disease have not been completely understood. Material & Methods: In this retrospective international multi-institutional study, we sought to investigate the short and long-term outcomes of patients who underwent PSH versus AH for multifocal CRLM at six tertiary referrals centers. Results: Among 1,841 patients who underwent surgery for CRLM, 299 (16%) patients had =4 metastasis and were included in the study. While 177 (59%) patients underwent AH, 122 (41%) patients underwent PSH with a mean of 5.2 liver resections. Patients undergoing AH had a mean tumor burden score (TBS) of 8.9 compared with 7.2 for patients in the PSH group (p<0.01). Even though the incidence of overall complications and bile leak was similar between the two groups (both p-values >0.20), patients in the PSH had a lower incidence of post-hepatectomy liver failure (PHLF) compared with AH patients (AH, n=10, 6% vs. PSH, n=1, 1%; p=0.03). The incidence of 90-day mortality was 6% (n=10) among AH patients compared with 1% (n=1) for PSH patients (p=0.03). In the multivariable survival model adjusted for TBS (HR=1.01), and genetic status (reference KRAS/NRAS/BRAF wild-type: KRAS/NRAS mutated, HR=1.5, BRAF mutated, HR=4.1), patients in the AH group had a 1.9-fold higher risk of death compared with PSH patients (reference PSH: AH patients, HR=1.9, p=0.015). Conclusion: While patients undergoing PSH for multifocal (=4 tumors) CRLM had a lower TBS than AH, PSH patients had a lower incidence of PHLF and 90-day mortality than AH patients. In the multivariable survival model adjusted for TBS and tumors' genetic status, AH patients had a higher risk of death compared with PSH patients.

BACKGROUND:Patients with hepatocellular carcinoma (HCC) and portal vein hypertension assessed with platelet count (PVH-PLT; platelet count < 100,000/mL) are often denied surgery even when the disease is technically resectable. Short- and long-term outcomes of patients undergoing minimally invasive surgery (MIS) versus open resection for HCC and PVH-PLT were compared. METHODS:Propensity score matching (PSM) was used to balance the clinicopathological differences between MIS and non-MIS patents. Univariate comparison and standard survival analyses were utilized. RESULTS:Among 1974 patients who underwent surgery for HCC, 13% had a PVH-PLT and 33% underwent MIS. After 1:1 PSM, 407 MIS and 407 non-MIS patients were analyzed. Incidence of complications and length-of-stay (LoS) were higher among non-MIS versus MIS patients (both p ≤ 0.002). After PSM, among 178 PVH-PLT patients (89 MIS and 89 non-MIS), patients who underwent a non-MIS approach had longer LoS (> 7 days; non-MIS: 55% vs. MIS: 29%), as well as higher morbidity (non-MIS: 42% vs. MIS: 29%) [p <0.001]. In contrast, long-term oncological outcomes were comparable, including 3-year overall survival (non-MIS: 66.2% vs. MIS: 72.9%) and disease-free survival (non-MIS: 47.3% vs. MIS: 50.2%) [both p ≥ 0.08]. CONCLUSION:An MIS approach was associated with improved short-term outcomes, but similar long-term outcomes, compared with open liver resection for patients with HCC and PVH-PLT. An MIS approach for liver resection should be considered for patients with HCC, even those individuals with PVH-PLT.

The ACS established an online risk calculator to help surgeons make patient-specific estimates of postoperative morbidity and mortality. Our objective was to assess the accuracy of the ACS-NSQIP calculator for estimating risk after curative intent resection for primary GI neuroendocrine tumors (GI-NETs). Adult patients with GI-NET who underwent complete resection from 2000 to 2017 were identified using a multi-institutional database, including data from eight academic medical centers. The ability of the NSQIP calculator to accurately predict a particular outcome was assessed using receiver operating characteristic curves and the area under the curve (AUC). Seven hundred three patients were identified who met inclusion criteria. The most commonly performed procedures were resection of the small intestine with anastomosis (N = 193, 26%) and partial colectomy with anastomosis (N = 136, 18%). The majority of patients were younger than 65 years (N = 482, 37%) and ASA Class III (N = 337, 48%). The most common comorbidities were diabetes (N = 128, 18%) and hypertension (N = 395, 56%). Complications among these patients based on ACS NSQIP definitions included any complication (N = 132, 19%), serious complication (N = 118, 17%), pneumonia (N = 7, 1.0%), cardiac complication (N = 1, 0.01%), SSI (N = 80, 11.4%), UTI (N = 17, 2.4%), venous thromboembolism (N = 18, 2.5%), renal failure (N = 16, 2.3%), return to the operating room (N = 27, 3.8%), discharge to nursing/rehabilitation (N = 22, 3.1%), and 30-day mortality (N = 9, 1.3%). The calculator provided reasonable estimates of risk for pneumonia (AUC = 0.721), cardiac complication (AUC = 0.773), UTI (AUC = 0.716), and discharge to nursing/rehabilitation (AUC = 0.779) and performed poorly (AUC < 0.7) for all other complications Fig. 1). The ACS-NSQIP risk calculator estimates a similar proportion of risk to actual events in patients with GI-NET but has low specificity for identifying the correct patients for many types of complications. The risk calculator may require modification for some patient populations.