Stromal Microenvironment Shapes the Intratumoral Architecture of Pancreatic Cancer.

Single-cell technologies have described heterogeneity across tissues, but the spatial distribution and forces that drive single-cell phenotypes have not been well defined. Combining single-cell RNA and protein analytics in studying the role of stromal cancer-associated fibroblasts (CAFs) in modulating heterogeneity in pancreatic cancer (pancreatic ductal adenocarcinoma [PDAC]) model systems, we have identified significant single-cell population shifts toward invasive epithelial-to-mesenchymal transition (EMT) and proliferative (PRO) phenotypes linked with mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signaling. Using high-content digital imaging of RNA in situ hybridization in 195 PDAC tumors, we quantified these EMT and PRO subpopulations in 319,626 individual cancer cells that can be classified within the context of distinct tumor gland "units." Tumor gland typing provided an additional layer of intratumoral heterogeneity that was associated with differences in stromal abundance and clinical outcomes. This demonstrates the impact of the stroma in shaping tumor architecture by altering inherent patterns of tumor glands in human PDAC.

Caregiver-reported quality of communication in pancreatic and periampullary cancer.

BACKGROUND: Communication between caregivers and clinical team members is critical for transitional care, but its quality and potential impact on outcomes are not well understood. This study reports on caregiver-reported quality of communication with clinical team members in the postpancreatectomy period and examines associations of these reports with patient and caregiver outcomes. METHODS: Caregivers of patients with pancreatic and periampullary malignancies who had undergone pancreatectomy were surveyed. Instrument measures assessed care experiences using the Caregiver Perceptions About Communication with Clinical Team Members (CAPACITY) instrument. The instrument has two main subscales: communication, assessing the extent to which providers helped caregivers comprehend details of clinical visits, and capacity, defined as the extent to which providers assessed whether caregivers were able to care for patients. RESULTS: Of 265 caregivers who were approached, 240 (90.6%) enrolled in the study. The mean communication and capacity subscale scores were 2.7 ± 0.6 and 1.5 ± 0.6, respectively (range, 0-4 [higher = better]). Communication subscale scores were lower among caregivers of patients who experienced (vs. those who did not experience) a 30-day readmission (2.6 ± 0.5 vs. 2.8 ± 0.6, respectively; p = .047). Capacity subscale scores were inversely associated with restriction in patient daily activities (a 0.04 decrement in the capacity score for every 1 point in daily activity restriction; p = .008). CONCLUSIONS: After pancreatectomy, patients with pancreatic and periampullary cancer whose caregivers reported worse communication with care providers were more likely to experience readmission. Caregivers of patients with greater daily activity restrictions were less likely to report being asked about the caregiver's skill and capacity by clinicians. PLAIN LANGUAGE SUMMARY: This prospective study used a validated survey instrument and reports on the quality of communication between health care providers and caregivers as reported by caregivers of patients with pancreatic and periampullary cancer after pancreatectomy. In an analysis of 240 caregivers enrolled in the study, lower communication scores (the extent to which providers helped caregivers understand clinical details) were associated with higher odds of 30-day patient readmission to the hospital. In addition, lower capacity scores (the extent to which providers assessed caregivers' ability to care for patients) were associated with greater impairment in caregivers. The strikingly low communication quality and capacity assessment scores suggest substantial room for improvement, with the potential to improve both caregiver and patient outcomes.

The Revised R Status is an Independent Predictor of Postresection Survival in Pancreatic Cancer After Neoadjuvant Treatment.

OBJECTIVE: To investigate the oncological outcomes of patients with pancreatic ductal adenocarcinoma (PDAC) who had an R 0 or R 1 resection based on the revised R status (1 mm) after neoadjuvant therapy (NAT). BACKGROUND: The revised R status is an independent prognostic factor in upfront-resected PDAC; however, the significance of 1 mm margin clearance after NAT remains controversial. METHODS: Patients undergoing pancreatectomy after NAT for PDAC were identified from 2 prospectively maintained databases. Clinicopathological and survival data were analyzed. The primary outcomes were overall survival (OS), recurrence-free survival (RFS), and pattern of recurrence in association with R 0 >1 mm and R 1 ≤1 mm resections. RESULTS: Three hundred fifty-seven patients with PDAC were included after NAT and subsequent pancreatic resection. Two hundred eight patients (58.3%) received FOLFIRINOX, 41 patients (11.5%) received gemcitabine-based regimens, and 299 individuals (83.8%) received additional radiotherapy. R 0 resections were achieved in 272 patients (76.2%) and 85 patients (23.8%) had R 1 resections. Median OS after R 0 was 41.0 months, compared with 20.6 months after R 1 resection ( P = 0.002), and even longer after additional adjuvant chemotherapy ( R 0 44.8 vs R1 20.1 months; P = 0.0032). Median RFS in the R 0 subgroup was 17.5 months versus 9.4 months in the R 1 subgroup ( P < 0.0001). R status was confirmed as an independent predictor for OS ( R 1 hazard ratio: 1.56, 95% CI: 1.07-2.26) and RFS ( R 1 hazard ratio: 1.52; 95% CI: 1.14-2.0). In addition, R 1 resections were significantly associated with local but not distant recurrence ( P < 0.0005). CONCLUSIONS: The revised R status is an independent predictor of postresection survival and local recurrence in PDAC after NAT. Achieving R 0 resection with a margin of at least 1 mm should be a primary goal in the surgical treatment of PDAC after NAT.

Lymph Node Yield is Associated with Improved Overall Survival and Increased Time to Recurrence in Node-Negative Pancreatic Ductal Adenocarcinoma Following Neoadjuvant Therapy.

OBJECTIVE: To determine if lymph node yield (LNY) is associated with improved overall survival (OS) and time to recurrence (TTR) in patients with node-negative pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant therapy (NAT). BACKGROUND: Lymph node yield has been associated with survival in solid gastrointestinal cancers, including PDAC. METHODS: Patients with pathological T stage I-III, node-negative (N0), PDAC treated with NAT followed by pancreatoduodenectomy were identified in the Massachusetts General Hospital (MGH) pancreatectomy database and the National Cancer Database (NCDB). A cutoff point of 22 nodes was identified in the NCDB using the point with the optimal (log-rank test) split. Overall survival and TTR were evaluated using univariate and multivariable analyses. RESULTS: In the MGH cohort, 233 node-negative patients following NAT were included. A LNY ≥ 22 was associated with prolonged median OS (59 months vs. 25 months, P<0.001) and prolonged TTR (32 months vs. 14 months, P=0.019). On multivariable analysis, LNY was an independent predictor of survival (HR 0.97, 95% CI 0.95-0.99, P=0.034) per sampled node. In the NCDB, 2,029 node-negative patients following NAT were included. A LNY ≥ 22 was associated with prolonged median OS (49 months vs. 33 months, P<0.001). On multivariable analysis, LNY was an independent predictor of survival (HR 0.99, 95% CI 0.98-0.99, P<0.001) per sampled node. CONCLUSION: Lymph node yield was associated with improved oncologic outcomes in patients treated with NAT followed by pancreatoduodenectomy in two independent datasets. Responsible mechanisms by which LNY impacts the outcomes of node-negative patients following NAT warrant further exploration.

Reappraising the Role of Intraoperative Neck Margin Revision in Post-Neoadjuvant Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Multi-Institutional Analysis.

OBJECTIVE: To investigate whether revision of pancreatic neck margin based on intraoperative frozen section analysis has oncologic value in post-neoadjuvant pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). SUMMARY BACKGROUND DATA: The role of intraoperative neck margin revision has been controversial, with little information specific to post-neoadjuvant PD. METHODS: Patients who underwent post-neoadjuvant PD (2013-2019) for conventional PDAC with frozen section analysis of neck margin at three academic institutions were included. Overall survival (OS) and recurrence-free survival (RFS) were compared across three groups: complete resection achieved en-bloc (CR-EB), complete resection achieved non-en-bloc (CR-NEB), and incomplete resection (IR). RESULTS: Among the 671 patients included, 524 (78.1%) underwent CR-EB, 119 (17.7%) CR-NEB and 28 (4.2%) IR. Patients undergoing CR-NEB and IR exhibited larger tumors and lower rates of RECIST response, requiring vascular resections more often. Likewise, CR-NEB and IR were associated with a worse pathological profile than CR-EB. The incidence of postoperative complications and access to adjuvant treatment were comparable among groups. A CR-EB was associated with the longest OS duration (34.3 mo). In patients with positive neck margin, obtaining a CR-NEB via re-excision was associated with a comparable OS relative to patients with an IR (26.9 vs. 27.1 mo, P=0.901). Similar results were observed for RFS. At multivariable analysis, neck margin status was not independently associated with survival and recurrence. CONCLUSION: Conversion of an initially positive pancreatic neck margin by additional resection is not associated with oncologic benefits in post-neoadjuvant PD and cannot be routinely recommended.

Author Correction: High-fat diet enhances stemness and tumorigenicity of intestinal progenitors.

In Fig. 4e of this Article, the labels for 'Control' and 'HFD' were reversed ('Control' should have been labelled blue rather than purple, and 'HFD' should have been labelled purple rather than blue). Similarly, in Fig. 4f of this Article, the labels for 'V' and 'GW' were reversed ('V' should have been labelled blue rather than purple, and 'GW' should have been labelled purple instead of blue). The original figure has been corrected online.

Underlying Bias in the Treatment of Pancreatic Cancer: Minorities Treated at the Same Facilities are Less Likely to Receive Neoadjuvant Therapy.

OBJECTIVE: To identify disparities in access to NAT for PDAC at the prehospital and intrahospital phases of care. SUMMARY OF BACKGROUND DATA: Delivery of NAT in PDAC is susceptible to disparities in access. There are limited data that accurately locate the etiology of disparities at the prehospital and intrahospital phases of care. METHODS: Retrospective cohort of patients ≥18 years old with clinical stage I-II PDAC from the 2010-2016 National Cancer Database. Multiple logistic regression was used to assess 2 sequential outcomes: (1) access to an NAT facility (prehospital phase) and (2) receipt of NAT at an NAT facility (intrahospital phase). RESULTS: A total of 36,208 patients were included for analysis in the prehospital phase of care. Higher education, longer travel distances, being treated at academic/research or integrated network cancer programs, and more recent year of diagnosis were independently associated with receipt of treatment at an NAT facility. All patients treated at NAT facilities (31,099) were included for the second analysis. Higher education level and receiving care at an academic/research facility were independently associated with increased receipt of NAT. NonBlack racial minorities (including American Indian, Asian, Pacific Islanders), being Hispanic, being uninsured, and having Medicaid insurance were associated with decreased receipt of NAT at NAT facilities. CONCLUSIONS: Non-Black racial minorities and Hispanic patients were less likely to receive NAT at NAT facilities compared to White and non-Hispanic patients, respectively. Discrepancies in administration of NAT while being treated at NAT facilities exist and warrant urgent further investigation.

Enhanced Recovery After Surgery Patients Are Prescribed Fewer Opioids at Discharge: A Propensity-score Matched Analysis.

OBJECTIVE: We aimed to compare discharge opioid prescriptions pre- and post-ERAS implementation. SUMMARY OF BACKGROUND DATA: ERAS programs decrease inpatient opioid use, but their relationship with postdischarge opioids remains unclear. METHODS: All patients undergoing hysterectomy between October 2016 and November 2020 and pancreatectomy or hepatectomy between April 2017 and November 2020 at 1 tertiary care center were included. For each procedure, ERAS was implemented during the study period. PSM was performed to compare pre - versus post-ERAS patients on discharge opioids (number of pills and oral morphine equivalents). Patients were matched on age, sex, race, payor, American Society of Anesthesiologists score, prior opioid use, and procedure. Sensitivity analyses in open versus minimally invasive surgery cohorts were performed. RESULTS: A total of 3983 patients were included (1929 pre-ERAS; 2054 post-ERAS). Post-ERAS patients were younger (56.0 vs 58.4 years; P < 0.001), more often female (95.8% vs 78.1%; P < 0.001), less often white (77.2% vs 82.0%; P < 0.001), less often had prior opioid use (20.1% vs 28.1%; P < 0.001), and more often underwent hysterectomy (91.1% vs 55.7%; P < 0.001). After PSM, there were no significant differences between cohorts in baseline characteristics. Matched post-ERAS patients were prescribed fewer opioid pills (17.4 pills vs 22.0 pills; P < 0.001) and lower oral morphine equivalents (129.4 mg vs 167.6 mg; P < 0.001) than pre-ERAS patients. Sensitivity analyses confirmed these findings [open (18.8 pills vs 25.4 pills; P < 0.001 \ 138.9 mg vs 198.7 mg; P < 0.001); minimally invasive surgery (17.2 pills vs 21.1 pills; P < 0.001 \ 127.1 mg vs 160.1 mg; P < 0.001). CONCLUSIONS: Post-ERAS patients were prescribed significantly fewer opioids at discharge compared to matched pre-ERAS patients.

Uncinate Duct Dilatation Predicts Additional Risk for High-Grade Dysplasia or Invasive Carcinoma Among Fukuoka-Positive Intraductal Papillary Mucinous Neoplasms.

OBJECTIVE: To determine whether uncinate duct dilatation (UDD) increases the risk of high-grade dysplasia or invasive carcinoma (HGD/IC) in Fukuoka-positive intraductal papillary mucinous neoplasms (IPMNs). BACKGROUND: Though classified as a branch duct, the uncinate duct is the primary duct of the pancreatic ventral anlage. We hypothesized that UDD, like main duct dilatation, confers additional risk for HGD/IC. METHODS: A total of 467 patients met inclusion criteria in a retrospective cohort study of surgically resected IPMNs at the Massachusetts General Hospital. We used multivariable logistic regression to analyze the association between UDD (defined as ≥4 mm) and HGD/IC, controlling for Fukuoka risk criteria. In a secondary analysis, the modeling was repeated in the 194 patients with dorsal branch duct IPMNs (BD-IPMNs) in the pancreatic neck, body, or tail. RESULTS: Mean age at surgery was 70, and 229 (49%) patients were female. In total, 267 (57%) patients had only worrisome features and 200 (43%) had at least 1 high-risk feature. UDD was present in 164 (35%) patients, of whom 118 (73%) had HGD/IC. On multivariable analysis, UDD increased the odds of HGD/IC by 2.8-fold, even while controlling for Fukuoka risk factors (95% CI: 1.8-4.4, P <0.001). Prevalence of HGD/IC in all patients with UDD was 73%, compared with 74% in patients with high-risk stigmata and 73% in patients with main duct IPMNs. In the secondary analysis, UDD increased the odds of HGD/IC by 3.2-fold in patients with dorsal BD-IPMNs (95% CI: 1.3-7.7, P =0.010). CONCLUSIONS: UDD confers additional risk for HGD/IC unaccounted for by current Fukuoka criteria. Further research can extend this study to Fukuoka-negative patients, including unresected patients.

Grading Pancreatic Neuroendocrine Tumors Via Endoscopic Ultrasound-guided Fine Needle Aspiration: A Multi-institutional Study.

OBJECTIVES: To identify factors associated with concordance between World Health Organization (WHO) grade on cytological analysis (c-grade) and histopathological analysis (h-grade) of surgical specimen in patients with PanNETs and examine trends in utilization and accuracy of EUS-FNA in preoperatively predicting grade. BACKGROUND: WHO grading system is prognostic in pancreatic neuroendo-crine tumors (PanNETs). The concordance between c-grade and h-grade is reported to be between 50% and 92%. METHODS: A multicenter retrospective study was performed on patients undergoing resection for PanNETs at four high-volume centers between 2010 and 2019. Patients with functional or syndrome-associated tumors, and those receiving neoadjuvant therapy were excluded. Factors associated with concordance between c-grade and h-grade and trends of utilization of EUS-FNA were assessed. RESULTS: Of 869 patients included, 517 (59.5%) underwent EUS-FNA; 452 (87.4%) were diagnostic of PanNETs and WHO-grade was reported for 270 (59.7%) patients. The concordance between c-grade and h-grade was 80.4% with moderate concordance ( Kc = 0.52, 95% CI: 0.41-0.63). Significantly higher rates of concordance were observed in patients with smaller tumors (<2 vs. ≥2cm, 81.1% vs. 60.4%, P = 0.005). Highest concordance (98.1%) was observed in patients with small tumors undergoing assessment between 2015-2019 with a near-perfect concordance ( Kc = 0.88, 95% CI: 0.61-1.00). An increase in the utilization of EUS-FNA (56.1% to 64.1%) was observed over the last 2 decades ( P = 0.017) and WHO-grade was more frequently reported (44.2% vs. 77.6%, P < 0.001). However, concordance between c-grade and h-grade did not change significantly (P = 0.118). CONCLUSION: Recently, a trend towards increasing utilization and improved diagnostic accuracy of EUS-FNA has been observed in PanNETs. Concordance between c-grade and h-grade is associated with tumor size with near-perfect agreement when assessing PanNETs <2cm in size.

"Evolving Trends in Pancreatic Cystic Tumors: A 3-Decade Single-Center Experience With 1290 Resections".

OBJECTIVE: The aim of this study was to describe our institutional experience with resected cystic tumors of the pancreas with emphasis on changes in clinical presentation and accuracy of preoperative diagnosis. SUMMARY BACKGROUND DATA: Incidental discovery of pancreatic cystic lesions has increased and has led to a rise in pancreatic resections. It is important to analyze surgical outcomes from these procedures, and the prevalence of malignancy, pre-malignancy and resections for purely benign lesions, some of which may be unintended. METHODS: Retrospective review of a prospective database spanning 3 decades. Presence of symptoms, incidental discovery, diagnostic studies, type of surgery, postoperative outcomes, and concordance between presumptive diagnosis and final histopathology were recorded. RESULTS: A total of 1290 patients were identified, 62% female with mean age of 60 years. Fifty-seven percent of tumors were incidentally discovered. Ninety-day operative mortality was 0.9% and major morbidity 14.4%. There were 23 different diagnosis, but IPMN, MCN, and serous cystadenoma comprised 80% of cases. Concordance between preoperative and final histopathological diagnosis increased by decade from 45%, to 68%, and is presently 80%, rising in parallel with the use of endoscopic ultrasound, cytology, and molecular analysis. The addition of molecular analysis improved accuracy to 91%. Of misdiagnosed cases, half were purely benign and taken to surgery with the presumption of malignancy or premalignancy. The majority of these were serous cystadenomas. CONCLUSIONS: Indications and diagnostic work-up of cystic tumors of the pancreas have changed over time. Surgical resection can be performed with very low mortality and acceptable morbidity and diagnostic accuracy is presently 80%. About 10% of patients are still undergoing surgery for purely benign lesions that were presumed to be malignant or premalignant. Further refinements in diagnostic tests are required to improve accuracy.

Recurring Pancreatic Neuroendocrine Tumor: Timing and Pattern of Recurrence and Current Treatment.

OBJECTIVE: The objective of this study was to describe the pattern of recurrence, treatments received, as well the oncological outcomes, of pancreatic neuroendocrine tumors (PanNETs) following curative surgery. BACKGROUND: PanNETs recur in 10% to 15% of cases following surgery. Information on the natural history and management of recurring disease is lacking. MATERIALS AND METHODS: Patients with PanNET that underwent curative surgery at 4 institutions between 2000 and 2019 were identified. Patients with poorly differentiated tumors, unknown tumor grade and differentiation, hereditary syndromes, unknown margin or R2 status, metastatic, and those that had neoadjuvant treatment or perioperative mortality were excluded. Clinical variables were assessed including first site of recurrence, treatment received, and survival outcomes. RESULTS: A total of 1402 patients were included: 957 (74%) had grade 1, 322 (25%) had grade 2, and 13 (1%) had grade 3 tumors. Median follow-up was 4.8 years (interquartile range: 2-8.2 years). Cumulative incidence of recurrence at 5 years was 13% (95% CI: 11%-15.2%) for distant disease, 1.4% (95% CI: 0.8%-2.3%) for locoregional recurrence, and 0.8% (95% CI: 0.4%-1.5%) for abdominal nodal recurrence. Patients who recurred had 2.89 increased risk of death (95% CI: 2-4.1) as compared with patients who did not recur. Therapy postrecurrence included: somatostatin analogs in 111 (61.0%), targeted therapies in 48 (26.4%), liver-directed therapies in 61 (33.5%), peptide receptor radionuclide therapy in 30 (16.5%), and surgery in 46 (25.3%) patients. Multiple treatments were used in 103 (57%) cases. After the first recurrence, 5-year overall survival was 74.6% (95% CI: 67.4%-82.5%). CONCLUSIONS: Recurrence following surgery is infrequent but reduces survival. Most recurrences are distant and managed with multiple therapies. Prospective studies are needed to establish strategies for surveillance and the sequence of treatment to control the disease and prolong survival.

Feasibility, Safety, and Efficacy of Aggressive Multimodal Management of Elderly Patients with Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: We aimed to evaluate the safety and efficacy of NAT followed by surgical resection in patients with PDAC aged ≥75 years. SUMMARY BACKGROUND DATA: Whether administration of neoadjuvant therapy (NAT) followed by surgical resection in elderly patients with pancreatic ductal adenocarcinoma (PDAC) is safe and effective is unknown. METHODS: The present study is a three-part comparison of older (≥ 75 years) versus younger (< 75 years) patients in different settings throughout the continuum of PDAC care. The first analysis was a comparison of older versus younger consecutive patients with non-metastatic PDAC who were initiated on FOLFIRINOX. The second was a comparison of older vs. younger patients who underwent NAT followed by surgical resection, and the third and final analysis was a comparison of older patients who underwent either NAT followed by surgical resection vs. upfront surgical resection. Postoperative complications, overall survival (OS), and time to recurrence (TTR), were compared. Propensity-score matching (PSM) analysis was performed to adjust for potential confounders. RESULTS: In the first analysis, a lower proportion of older patients (n=40) were able to complete the intended neoadjuvant FOLFIRINOX (8) cycles compared to younger patients (n=214) (65.0% vs. 81.4%, P=0.021). However, older patients were just as likely to undergo surgical exploration as younger patients (77.5% vs 78.5%, P=0.89) as well as surgical resection (57.5% vs 55.6%, P=0.70). In the second analysis, PSM was conducted to compare older (n=54) vs. younger patients (n=54) who underwent NAT followed by surgical resection. There were no significant differences in postoperative complications between the matched groups. While there was a significant difference in overall survival (OS) between older and younger patients (median OS: 16.43 months vs. 30.83 months, P=0.002), importantly, there was no significant difference in time to recurrence (TTR, median: 7.65 months vs. 11.83 months, P=0.215). In the third analysis, older patients who underwent NAT followed by surgical resection (n=48) were compared with similar older patients who underwent upfront surgical resection (n=48). After PSM, there was a significant difference in OS (median OS: 15.78 months vs. 11.51 months, P=0.037) as well as TTR (median TTR: 8.81 months vs. 7.10 months, P=0.046) representing an association with improved outcomes that favored the neoadjuvant approach among older patients alone. CONCLUSIONS: This comprehensive three-part study showed that administration of NAT followed by surgical resection appears to be safe and effective among patients ≥ 75 years of age. An aggressive approach should be offered to older adults undergoing multimodal treatment of PDAC.

The Role of Adjuvant Therapy in Duodenal Adenocarcinoma and Intestinal Subtype Ampullary Carcinoma after Curative Resection.

OBJECTIVE: Defining the role of adjuvant therapy in duodenal adenocarcinoma (DAC) and intestinal subtype ampullary carcinoma (iAC). SUMMARY BACKGROUND DATA: DAC and iAC share a similar histological differentiation but the benefit of adjuvant therapy remains unclear. METHODS: Patients undergoing curative-intent surgical resection for DAC and iAC between 2010 and 2021 at five high-volume centers were included. Patient baseline, perioperative and long-term oncological outcomes were evaluated. Statistical testing was performed with SPSS 25 (IBM). RESULTS: A total of 136 patients with DAC and 171 with iAC were identified. Patients with DAC had more advanced tumors than those with iAC. Median overall survival (OS) in DAC patients was 101 months versus 155 months for iAC patients (P=0.098). DAC had a higher rate of local (14.1% vs. 1.2%, P<0.001) and systemic recurrence (30.4% vs. 3.5%, P<0.001). Adjuvant therapy failed to improve overall survival in all patients with DAC and iAC. For DAC, patients with perineural invasion, but not other negative prognostic factors had improved OS rates with adjuvant therapy (72 m vs. 44 m, P=0.044). IAC patients with N+ (190 m vs. 57 m, P=0.003), T3-4 (177 m vs. 59 m, P=0.050) and perineural invasion (150 m vs. 59 m, P=0.019) had improved OS rates with adjuvant therapy. CONCLUSION: While adjuvant therapy fails to improve OS in all patients with DAC and iAC in the current study, it improved overall survival in DAC patients with perineural invasion and in iAC patients with T3-4 tumors, positive lymph nodes, and perineural invasion.

Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) Versus the Standard of Care Imaging in the Diagnosis of Peritoneal Carcinomatosis.

OBJECTIVE: To compare positron emission tomography (PET)/magnetic resonance imaging (MRI) to the standard of care imaging (SCI) for the diagnosis of peritoneal carcinomatosis (PC) in primary abdominopelvic malignancies. SUMMARY BACKGROUND DATA: Identifying PC impacts prognosis and management of multiple cancer types. METHODS: Adult subjects were prospectively and consecutively enrolled from April 2019 to January 2021. Inclusion criteria were: 1) acquisition of whole-body contrast-enhanced (CE) 18F-fluorodeoxyglucose PET/MRI, 2) pathologically confirmed primary abdominopelvic malignancies. Exclusion criteria were: 1) greater than 4 weeks interval between SCI and PET/MRI, 2) unavailable follow-up. SCI consisted of whole-body CE PET/computed tomography (CT) with diagnostic quality CT, and/or CE-CT of the abdomen and pelvis, and/or CE-MRI of the abdomen±pelvis. If available, pathology or surgical findings served as the reference standard, otherwise, imaging followup was used. When SCI and PET/MRI results disagreed, medical records were checked for management changes. Follow-up data were collected until August 2021. RESULTS: One hundred sixty-four subjects were included, 85 (52%) were female, and the median age was 60 years (interquartile range 50-69). At a subject level, PET/MRI had higher sensitivity (0.97, 95% CI 0.86-1.00) than SCI (0.54, 95% CI 0.37-0.71), P < 0.001, without a difference in specificity, of 0.95 (95% CI 0.90-0.98) for PET/MRI and 0.98 (95% CI 0.93-1.00) for SCI, P » 0.250. PET/MRI and SCI results disagreed in 19 cases. In 5/19 (26%) of the discordant cases, PET/MRI findings consistent with PC missed on SCI led to management changes. CONCLUSION: PET/MRI improves detection of PC compared with SCI which frequently changes management.

Association of Tumor Cell Metabolic Subtype and Immune Response With the Clinical Course of Hepatocellular Carcinoma.

AIM: Tumor metabolism plays an important role in tumorigenesis and tumor progression. This study evaluated the potential association of tumor cell metabolism and immune cell tumor infiltration with the clinical course of hepatocellular carcinoma (HCC). METHODS: Gene-wise normalization and principal component analysis were performed to evaluate the metabolic system. A tumor microenvironment score system of tumor immune cell infiltration was constructed to evaluate its association with metabolic subtypes. Finally, we analyzed the impact of metabolism and immune cell infiltration on the clinical course of HCC. RESULTS: A total of 673 HCC patients were categorized into cholesterogenic (25.3%), glycolytic (14.6%), mixed (10.4%), and quiescent (49.8%) types based on glycolysis and cholesterol biosynthesis gene expression. The subgroups including the glycolytic genotyping expression (glycolytic and mixed types) showed a higher mortality rate. The glycolytic, cholesterogenic, and mixed types were positively correlated with M0 macrophage, resting mast cell, and naïve B-cell infiltration (P = .013, P = .019, and P = .006, respectively). In TCGA database, high CD8+ T cell and low M0 macrophage infiltration were associated with prolonged overall survival (OS, P = .0017 and P < .0001, respectively). Furthermore, in glycolytic and mixed types, patients with high M0 macrophage infiltration had a shorter OS (P = .03 and P = .013, respectively), and in quiescent type, patients with low naïve B-cell infiltration had a longer OS (P = .007). CONCLUSIONS: Tumor metabolism plays a prognostic role and correlates with immune cell infiltration in HCC. M0 macrophage and CD8+ T cell appear to be promising prognostic biomarker for HCC. Finally, M0 macrophages may represent a useful immunotherapeutic target in patients with HCC.

Long-Term Outcomes of Tuberous Sclerosis Complex-Associated Non-functional Pancreatic Neuroendocrine Tumors: Should We Be More Conservative?

BACKGROUND: Hereditary syndromes such as tuberous sclerosis complex (TSC) account for 10% of pancreatic neuroendocrine tumors (PNETs). Surgical intervention is the current standard of care for sporadic PNETs (spPNETs) that are >2 cm in size. We compared the long-term outcomes of resected TSC-PNETs with patients with spPNETs. METHODS: We conducted a retrospective review of perioperative data and outcomes of TSC-PNETs compared with spPNETs. Inclusion criteria involved selecting patients whose tumors were no larger than 5.1 cm, the maximum size observed in the TSC-PNET group. RESULTS: Of the 347 patients resected for PNETs, 14 were TSC-PNETs and 241 were non-functional spPNETs. The median age for the whole cohort was 56 years (interquartile range [IQR] 21.0) and 47% were female. The median follow-up was 103.8 months (95% confidence interval [CI] 89.2-118.6). Specifically, 14 patients with TSC-PNETs and 194 patients with spPNETs were included. Compared with spPNETs, patients with TSC-PNETs were operated on at a younger age (24.0 vs. 57.5 years; p < 0.001), were more frequently multifocal (28.5% vs. 0.0%; p < 0.001), were more likely to undergo minimally invasive operations (78.6% vs. 24.3%; p < 0.001), and had more R1 resections (28.6% vs. 5.7%; p = 0.006). Local and distant tumor recurrence was only observed in the spPNET group. The 5-year mortality rates for the spPNET and TSC-PNET groups were 6.2% and 0.0%, respectively. No PNET-related deaths were observed among TSC-PNETs. CONCLUSION: None of the TSC-PNET patients recurred after a median follow-up of 78.0 months. The risk-benefit of aggressive pancreatic operations in TSC-PNET patients is still unclear and our findings suggest a conservative approach should be considered.

Predicting recurrence in pancreatic neuroendocrine tumours: role of ARX and alternative lengthening of telomeres (ALT).

BACKGROUND: While many pancreatic neuroendocrine tumours (PanNET) show indolent behaviour, predicting the biological behaviour of small nonfunctional PanNETs remains a challenge. Nonfunctional PanNETs with an epigenome and transcriptome that resemble islet alpha cells (ARX-positive) are more aggressive than neoplasms that resemble islet beta cells (PDX1-positive). In this study, we explore the ability of immunohistochemistry for ARX and PDX1 and telomere-specific fluorescence in situ hybridisation (FISH) for alternative lengthening of telomeres (ALT) to predict recurrence. METHODS: Two hundred fifty-six patients with PanNETs were identified, and immunohistochemistry for ARX and PDX1 was performed. Positive staining was defined as strong nuclear staining in >5% of tumour cells. FISH for ALT was performed in a subset of cases. RESULTS: ARX reactivity correlated with worse disease-free survival (DFS) (P = 0.011), while there was no correlation between PDX1 reactivity and DFS (P = 0.52). ALT-positive tumours (n = 63, 31.8%) showed a significantly lower DFS (P < 0.0001) than ALT-negative tumours (n = 135, 68.2%). ARX reactivity correlated with ALT positivity (P < 0.0001). Among nonfunctional tumours, recurrence was noted in 18.5% (30/162) of ARX-positive tumours and 7.5% (5/67) of ARX-negative tumours. Among WHO grade 1 and 2 PanNETs with ≤2 cm tumour size, 14% (6/43) of ARX-positive tumours recurred compared to 0 of 33 ARX-negative tumours and 33.3% (3/9) ALT-positive tumours showed recurrence versus 4.4% (2/45) ALT-negative tumours. CONCLUSION: Immunohistochemistry for ARX and ALT FISH status may aid in distinguishing biologically indolent cases from aggressive small low-grade PanNETs, and help to identify patients who may preferentially benefit from surgical intervention.

Reassessment of the Optimal Number of Examined Lymph Nodes in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: The aim of this study was to reappraise the optimal number of examined lymph nodes (ELNs) in pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). SUMMARY BACKGROUND DATA: The well-established threshold of 15 ELNs in PD for PDAC is optimized for detecting 1 positive node (PLN) per the previous 7th edition of the American Joint Committee on Cancer (AJCC) staging manual. In the framework of the 8th edition, where at least 4 PLN are needed for an N2 diagnosis, this threshold may be inadequate for accurate staging. METHODS: Patients who underwent upfront PD at 2 academic institutions between 2000 and 2016 were analyzed. The optimal ELN threshold was defined as the cut-point associated with a 95% probability of identifying at least 4 PLNs in N2 patients. The results were validated addressing the N-status distribution and stage migration. RESULTS: Overall, 1218 patients were included. The median number of ELN was 26 (IQR 17-37). ELN was independently associated with N2-status (OR 1.27, P < 0.001). The estimated optimal threshold of ELN was 28. This cut-point enabled improved detection of N2 patients and stage III disease (58% vs 37%, P = 0.001). The median survival was 28.6 months. There was an improved survival in N0/N1 patients when ELN exceeded 28, suggesting a stage migration effect (47 vs 29 months, adjusted HR 0.649, P < 0.001). In N2 patients, this threshold was not associated with survival on multivariable analysis. CONCLUSION: Examining at least 28 LN in PD for PDAC ensures optimal staging through improved detection of N2/stage III disease. This may have relevant implications for benchmarking processes and quality implementation.

Long-term Outcomes of Parenchyma-sparing and Oncologic Resections in Patients With Nonfunctional Pancreatic Neuroendocrine Tumors <3 cm in a Large Multicenter Cohort.

INTRODUCTION: The role of parenchyma-sparing resections (PSR) and lymph node dissection in small (<3 cm) nonfunctional pancreatic neuroendocrine tumors (PNET) is unlikely to be studied in a prospective randomized clinical trial. By combining data from 4 high-volume pancreatic centers we compared postoperative and long-term outcomes of patients who underwent PSR with patients who underwent oncologic resections. METHODS: Retrospective review of prospectively collected clinicopathologic data of patients who underwent pancreatectomy between 2000 and 2021 was collected from 4 high-volume institutions. PSR and lymph node-sparing resections (enucleation and central pancreatectomy) were compared to those who underwent oncologic resections with lymphadenectomy (pancreaticoduodenectomy, distal pancreatectomy). Statistical testing was performed using χ 2 test and t test, survival estimates with Kaplan-Meier method and multivariate analysis using Cox proportional hazard model. RESULTS: Of 810 patients with small sporadic nonfunctional PNETs, 121 (14.9%) had enucleations, 100 (12.3%) had central pancreatectomies, and 589 (72.7%) patients underwent oncologic resections. The median age was 59 years and 48.2% were female with a median tumor size of 2.5 cm. After case-control matching for tumor size, 221 patients were selected in each group. Patients with PSR were more likely to undergo minimally invasive operations (32.6% vs 13.6%, P <0.001), had less intraoperative blood loss (358 vs 511 ml, P <0.001) and had shorter operative times (180 vs 330 minutes, P <0.001) than patients undergoing oncologic resections. While the mean number of lymph nodes harvested was lower for PSR (n=1.4 vs n=9.9, P <0.001), the mean number of positive lymph nodes was equivalent to oncologic resections (n=1.1 vs n=0.9, P =0.808). Although the rate of all postoperative complications was similar for PSR and oncologic resections (38.5% vs 48.2%, P =0.090), it was higher for central pancreatectomies (38.5% vs 56.6%, P =0.003). Long-term median disease-free survival (190.5 vs 195.2 months, P =0.506) and overall survival (197.9 vs 192.6 months, P =0.372) were comparable. Of the 810 patients 136 (16.7%) had no lymph nodes resected. These patients experienced less blood loss, shorter operations ( P <0.001), and lower postoperative complication rates as compared to patients who had lymphadenectomies (39.7% vs 56.9%, P =0.008). Median disease-free survival (197.1 vs 191.9 months, P =0.837) and overall survival (200 vs 195.1 months, P =0.827) were similar for patients with no lymph nodes resected and patients with negative lymph nodes (N0) after lymphadenectomy. CONCLUSION: In small <3 cm nonfunctional PNETs, PSRs and lymph node-sparing resections are associated with lower blood loss, shorter operative times, and lower complication rates when compared to oncologic resections, and have similar long-term oncologic outcomes.