This study is the first to report discharge opioid prescribing practices in an ERAS setting. Although an ERAS intervention for colorectal surgery led to an increase in opioid-free anesthesia and multimodal analgesia, we did not observe an impact on discharge opioid prescribing practices. The majority of patients were discharged with an opioid prescription, including those with a combination of low discharge pain scores, no preoperative opioid use, and low morphine milligram equivalents consumption before discharge. This observation in the setting of an ERAS pathway that promotes multimodal analgesia suggests that our findings are very likely to also be observed in non-ERAS settings and offers an opportunity to modify opioid prescribing practices on discharge after surgery. For opioid-free anesthesia and multimodal analgesia to influence the opioid epidemic, the dose and quantity of the opioids prescribed should be modified based on the information gathered by in-hospital pain scores and opioid use as well as pain history before admission.

Results: Of the 70 patients, 50 (71.4%) had nonfunctional tumors. Thirty-seven patients (52.9%) had neuroendocrine carcinomas and 13 (18.6%) had benign islet cell neoplasms. Twenty patients had functional tumors. Of these 20 patients, 16 had insulinomas, 2 had glucagonomas, and 2 had gastrinomas. Twenty-seven patients underwent pancreaticoduodenectomy, 32 had distal pancreatectomy, and 11 underwent enucleation. Patients undergoing enucleation as compared with those not undergoing enucleation were younger (mean age, 39 vs 51 years, respectively; P=.009) and had smaller tumors (mean tumor size, 2 vs 5 cm, respectively; PϽ.001). Postoperative complications occurred in 13 patients (48.1%) after pancreaticoduodenectomy, in 4 patients (12.5%) after distal pancreatectomy, and in 0 patients after enucleation. There were no perioperative mortalities. With a median follow-up of 50 months, the 5-year actuarial survival for the patients with malignant neuroendocrine carcinomas (n=37) was 77%, and all of the patients with functional tumors are alive. The presence of lymphovascular invasion closely approached significance when survival was evaluated (P=.06). Lymph node status, perineural invasion, and liver metastasis did not impact survival. Conclusions: This single-institutional case series demonstrates that pancreatic neuroendocrine tumors can be safely resected without mortality and with minimal morbidity. The presence of lymphovascular invasion can be used to classify neuroendocrine tumors as malignant, and this appears to predict survival. Patients with malignant tumors can expect long-term survival even in the setting of metastatic disease.

We conclude that the rate of clinically apparent new onset diabetes after distal pancreatectomy is minimal. Alternative pancreatic resections aimed at preserving pancreatic mass are likely to be unwarranted.

Mutations of the RET proto-oncogene are responsible for several inherited human diseases and may function as genetic modifiers of the disease. However, the role of RET mutations in pancreatic cancer has not been studied. Expression of the glial cell line-derived neurotrophic factor (GDNF) receptors RET and GDNF family receptor A1 (GFRA1) in human pancreatic cancer cells was determined by Western blot, immunofluorescence, and flow cytometry. The effect of GDNF on cell proliferation and invasion was assessed. Small interfering RNA and antibodies were used to evaluate the involvement of RET. The G691S RET polymorphism was analyzed by sequencing and restriction analysis. The modifying effect of G691S RET on GDNF-induced invasion and mitogen-activated protein kinase (MAPK) signaling was evaluated. Transfection studies with wild-type and mutated RET determined the functional role of the G691S polymorphism. Pancreatic cancer specimens and matched tissues were analyzed for the presence of the G691S RET polymorphism. GDNF receptors were found on all cell lines. GDNF increased pancreatic cancer cell proliferation and invasion, which was mediated by RET. The effect of GDNF was more profound in cells with the G691S RET polymorphism (P < 0.01). G691S RET correlated with an enhanced activation of the downstream extracellular signal-regulated kinase pathway. Overexpression of G691S RET increased pancreatic cancer cell invasion. The G691S RET polymorphism was also detected in human pancreatic tumors and represented a somatic mutation in some patients. These findings indicate that the G691S RET single nucleotide polymorphism may directly correlate with the aggressive growth of pancreatic cancers and may function as a genetic modifier or even lowpenetrance gene. (Cancer Res 2005; 65(24): 11536-44)

Hypothesis: Pancreatic fistula (PF), a common and potentially lethal complication of pancreaticoduodenectomy, can be managed nonoperatively in most cases.

Background: Despite intent to cure surgery with negative resection margins, locoregional recurrence is common in pancreatic cancer. Aims: To determine whether detection of K-ras gene mutation in the histologically negative surgical margins of pancreatic cancer reflects unrecognised disease. Patients: Seventy patients who underwent curative resection for pancreatic ductal adenocarcinoma were evaluated. Methods: All patients had surgical resection margins (pancreatic transection and retroperitoneal) that were histologically free of invasive cancer. DNA was extracted from these paraffin embedded surgical margins and assessed by quantitative real time polymerase chain reaction to detect the K-ras gene mutation at codon 12. Detection of K-ras mutation was correlated with standard clinicopathological factors. Results: K-ras mutation was detected in histologically negative surgical margins of 37 of 70 (53%) patients. A significant difference in overall survival was demonstrated between patients with margins that were K-ras mutation positive compared with negative (median 15 v 55 months, respectively; p = 0.0008). By univariate and multivariate analyses, detection of K-ras mutation in the margins was a significant prognostic factor for poor survival (hazard ratio (HR) 2.8 (95% confidence interval (CI) 1.5-5.3), p = 0.0009; and HR 2.8 (95% CI 1.4-5.5), p = 0.004, respectively). Conclusions: Detection of cells harbouring K-ras mutation in histologically negative surgical margins of pancreatic cancer may represent unrecognised disease and correlates with poor disease outcome. The study demonstrates that molecular-genetic evaluation of surgical resection margins can improve pathological staging and prognostic evaluation of patients with pancreatic ductal adenocarcinoma.

Hypothesis: Although the safety of pancreaticoduodenectomy has notably improved over the past several decades, the reported survival of patients with pancreatic cancer remains poor. We hypothesized that, in recent years, the survival of patients with pancreatic adenocarcinoma following pancreaticoduodenectomy has substantially improved.

The MAGEA gene family that encodes cancer testis antigens is differentially expressed in many cancers. Though MAGEA3 expression has been detected in gastrointestinal malignancies, its role in pancreatic ductal adenocarcinoma (PDAC) has not been well established. We assessed 57 patients who underwent intentto-cure surgery for PDAC. Total RNA from paraffin-embedded pancreatic tumors was extracted and assessed for MAGEA3 gene expression by an optimized probe-based quantitative real-time RT-PCR (qRT) assay. MAGEA3 gene expression was detected by qRT in 25 (44%) patients. For the entire cohort, detection of MAGEA3 expression was associated with significantly decreased overall survival (median, 16 vs 33 months; log-rank, p 5 0.032). When clinicopathologic factors, including age, gender, stage, tumor extent, lymph node metastasis, tumor grade, perineural invasion and lymphovascular invasion were assessed by univariate analysis, MAGEA3 gene expression and tumor grade were significant prognostic factors for poor survival (HR 2.1, 95% CI: 1.0-4.4, p 5 0.041; and HR 3.7, 95% CI: 1.8-7.6, p 5 0.0004, respectively). Immunohistochemistry (IHC) was performed and confirmed MAGEA3 protein in PDAC specimens. In conclusion, MAGEA3 is differentially expressed in patients with PDAC; its expression correlates with significantly worse survival. Molecular assessment for MAGEA3 should be considered to improve prognostic evaluation and to identify eligible patients for potential immune-based therapy. ' 2005 Wiley-Liss, Inc.