Pancreatic Adenocarcinoma, Version 1.2019

Neoadjuvant Treatment in Locally Advanced Pancreatic Cancer (LAPC) Patients with FOLFIRINOX or Gemcitabine NabPaclitaxel: A Single-Center Experience and a Literature Review

The optimal therapeutic strategy for locally advanced pancreatic cancer patients (LAPC) has not yet been established. Our aim is to evaluate how surgery after neoadjuvant treatment with either FOLFIRINOX (FFN) or Gemcitabine-NabPaclitaxel (GemNab) affects the clinical outcome in these patients. LAPC patients treated at our institution were retrospectively analysed to reach this goal. The group characteristics were similar: 35 patients were treated with the FOLFIRINOX regimen and 21 patients with Gemcitabine Nab-Paclitaxel. The number of patients undergoing surgery was 14 in the FFN group (40%) and six in the GemNab group (28.6%). The median Disease-Free Survival (DFS) was 77.10 weeks in the FFN group and 58.65 weeks in the Gem Nab group (p = 0.625), while the median PFS in the unresected group was 49.4 weeks in the FFN group and 30.9 in the GemNab group (p = 0.0029, 95% CI 0.138-0.862, HR 0.345). The overall survival (OS) in the resected population needs a longer follow up to be completely assessed, while the median overall survival (mOS) in the FFN group was 72.10 weeks and 53.30 weeks for the GemNab group (p = 0.06) in the unresected population. Surgery is a valuable option for LAPC patients and it is able to induce a relevant survival advantage. FOLFIRINOX and Gem-NabPaclitaxel should be offered as first options to pancreatic cancer patients in the locally advanced setting.

Locally Advanced Pancreatic Cancer: Work-Up, Staging, and Local Intervention Strategies

Locally advanced pancreatic cancer (LAPC) has several definitions but essentially is a nonmetastasized pancreatic cancer, in which upfront resection is considered not beneficial due to extensive vascular involvement and consequent high chance of a nonradical resection. The introduction of FOLFIRINOX chemotherapy and gemcitabine-nab-paclitaxel (gem-nab) has had major implications for the management and outcome of patients with LAPC. After 4-6 months induction chemotherapy, the majority of patients have stable disease or even tumor-regression. Of these, 12 to 35% are successfully downstaged to resectable disease. Several studies have reported a 30-35 months overall survival after resection; although it currently remains unclear if this is a result of the resection or the good response to chemotherapy. Following chemotherapy, selection of patients for resection is difficult, as contrast-enhanced computed-tomography (CT) scan is unreliable in differentiating between viable tumor and fibrosis. In case a resection is not considered possible but stable disease is observed, local ablative techniques are being studied, such as irreversible electroporation, radiofrequency ablation, and stereotactic body radiation therapy. Pragmatic, multicenter, randomized studies will ultimately have to confirm the exact role of both surgical exploration and ablation in these patients. Since evidence-based guidelines for the management of LAPC are lacking, this review proposes a standardized approach for the treatment of LAPC based on the best available evidence.

Accuracy of Nodal Positivity in Inadequate Lymphadenectomy in Pancreaticoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Population Study Using the US SEER Database

Objectives: The optimal number of the examined lymph nodes (ELNs) in pancreaticoduodenectomy for pancreatic ductal adenocarcinoma has been widely studied. However, the accuracy of nodal positivity for the patients with inadequate lymphadenectomy is still unclear. The purpose of our study was to determine the accuracy of the number of positive nodes reported for patients with 1-3 positive nodes and the probability that 4 or more nodes could be positive along with tumor size and number of nodes examined. Methods: We obtained data on patients who underwent pancreaticoduodenectomy for resectable pancreatic ductal adenocarcinoma diagnosed during 2004-2013 from the US Surveillance, Epidemiology, and End Results registry. An mathematical model based on Hypergeometric Distribution and Bayes' Theorem was used to estimate the accuracy. Results: Among the 9,945 patients, 55.6% underwent inadequate lymphadenectomy. Of them, 1,842, 6,049, and 2,054 had T1, T2, and T3 stage disease, respectively. The accuracy of the number of observed positive nodes increased as the number of ELNs increased and the tumor size decreased. To rule out the possibility of N2 stage (4 and more positive nodes), there should be at least 13 ELNs for the patients with 1 observed positive lymph node and 14 for the patients with 2. Conclusion: Inadequate lymphadenectomy could result in underestimation of the N stage, and this would have adverse impact on recurrence, efficacy of postoperative treatment, and even overall survival. This model combined with the observed positive lymph nodes, the number of ELNs, and tumor size could provide a more accurate determination of nodal positivity of these patients.