Comparison of oncologic outcomes between open and laparoscopic distal pancreatectomy for pancreatic ductal adenocarcinoma using data from the KOTUS-BP national database: overcoming selection bias and the necessity of definite indications.

BACKGROUND: Despite the lack of high-level evidence, laparoscopic distal pancreatectomy (LDP) is frequently performed in patients with pancreatic ductal adenocarcinoma (PDAC) owing to advancements in surgical techniques. The aim of this study was to investigate the long-term oncologic outcomes of LDP in patients with PDAC via propensity score matching (PSM) analysis using data from a large-scale national database. METHODS: A total of 1202 patients who were treated for PDAC via distal pancreatectomy across 16 hospitals were included in the Korean Tumor Registry System-Biliary Pancreas. The 5-year overall (5YOSR) and disease-free (5YDFSR) survival rates were compared between LDP and open DP (ODP). RESULTS: ODP and LDP were performed in 846 and 356 patients, respectively. The ODP group included more aggressive surgeries with higher pathologic stage, R0 resection rate, and number of retrieved lymph nodes. After PSM, the 5YOSRs for ODP and LDP were 37.3% and 41.4% (p = 0.150), while the 5YDFSRs were 23.4% and 27.2% (p = 0.332), respectively. Prognostic factors for 5YOSR included R status, T stage, N stage, differentiation, and lymphovascular invasion. CONCLUSION: LDP was performed in a selected group of patients with PDAC. Within this group, long-term oncologic outcomes were comparable to those observed following ODP.

Pancreatic metastasis from papillary thyroid cancer: a case report and literature review.

Pancreatic metastasis from papillary thyroid cancer (PTC) is extremely rare; only 18 cases have been reported in the literature. However, several reviews have highlighted similar characteristics between metastatic and primary pancreatic tumors. The patient was a 51-year-old male with a history of total thyroidectomy, modified radical neck dissection, and radioactive iodine ablation for PTC in 2014. Nodules suspected of metastasis were found in both lungs on chest computed tomography (CT). However, after 6 months, a follow-up chest CT showed no increase in size; thus, a follow-up observation was planned. Six years after his initial diagnosis, abdominal CT and pancreas magnetic resonance imaging revealed a 4.7 cm cystic mass with a 2.5 cm enhancing mural nodule in the pancreas tail. We diagnosed the pancreatic lesion as either metastatic cancer or primary pancreas cancer. The patient underwent distal pancreato-splenectomy. After surgery, the pathological report revealed that the mass was metastatic PTC. Pancreatic metastasis from PTC indicates an advanced tumor stage and poor prognosis. However, pancreatectomy can increase the survival rate when the lesion is completely resectable. Therefore, surgical resection should be considered as a treatment for pancreatic metastasis from PTC.

The prognostic value of the lymph node ratio in patients with distal cholangiocarcinoma after curative intended surgery: A single-center retrospective study.

Backgrounds/Aims: The goal of the present study was to evaluate the prognostic value of lymph node ratio (LNR) in distal cholangiocarcinoma (DCC) after curative intended surgery. Methods: Clinicopathological data of 162 DCC patients who underwent radical intended surgery between 2012 and 2020 were analyzed retrospectively. Prognostic factors related to overall survival (OS) and disease-free survival (DFS) were evaluated. Results: Median OS time and DFS time were 41 and 29 months, and 5-year OS rate and DFS rate were 44.7% and 38.1%, respectively. In the univariate analysis, significant prognostic factors for OS were histologic differentiation, American Joint Committee on Cancer (AJCC) stage, positive lymph node count, LNR, R1 resection, and perineural invasion. Preoperative carcinoembryonic antigen, carbohydrate antigen 19-9, infiltrative type, histologic differentiation, AJCC stage, positive lymph node count, LNR, R1 resection, perineural invasion, and lymph-vascular invasion were significant prognostic factors for DFS in the univariate analysis. In the multivariate analysis, histologic differentiation, R1 resection, and LNR were the independent prognostic factors for both OS and DFS. The LNR ≥ 0.2 group had a significantly poor prognosis in terms of OS (hazard ratio, 3.915; p = 0.002) and DFS (hazard ratio, 5.840; p < 0.001). Conclusions: LNR has significant value as a prognostic factor of DCC related to OS and DFS. LNR has the potential to be used as a modified staging system with furthermore studies.

Gallbladder paraganglioma with hemorrhage: A case report and literature review.

Gallbladder paraganglioma (GP) is a rare tumor, with only 12 cases reported in the literature to date. Due to its rarity, clinical information of GP is insufficient. We present a case of GP in a 48-year-old female along with a literature review of all GP cases described to date. A 48-year-old female presented with intermittent right upper abdominal pain. Preoperative imaging revealed a hematoma in the gallbladder lumen without any definite etiology. Laparoscopic cholecystectomy was performed. Gross examination of the gallbladder revealed multiple small stones and a large hematoma as well as a 1.6-cm-sized polypoid mass at the gallbladder fundus. Microscopic study of the polypoid mass showed a zellballen appearance. Immunohistochemical analysis revealed that the mass was positive for synaptophysin, CD56, and chromogranin, suggesting GP. GP is difficult to diagnose because of non-specific clinical findings. Almost all GP cases are diagnosed based on histologic findings after cholecystectomy. Simple cholecystectomy was performed as a treatment in all reported cases of GP, including our case. There was no postoperative tumor recurrence or metastasis after surgery.

Comparison of laparoscopic versus open distal pancreatectomy for benign, pre-malignant, and low grade malignant pancreatic tumors.

BACKGROUNDS/AIMS: The purpose of this study is to demonstrate that laparoscopic distal pancreatectomy in benign disease is is safer and more favorable to patients than open distal pancreatectomy. METHODS: We retrospectively reviewed data of 150 patients who underwent laparoscopic (n=69) or open (=81) distal pancreatectomy at a double institutes from 2008 to 2018. We reviewed each patient's history for age, sex, pathologic diagnosis. Specific outcomes that were included hospital stay, operative time (in minutes), operative blood loss (in milliliters), 30-daymajormorbidity and mortality (Clavian-Dindo classification), pancreatic leak rate (grade of leak A, B, or C), pancreatic hemorrhage. RESULTS: From 2008 to 2018, there were 150 patients underwent distal pancreatectomy with or without splenectomy for benign pancreatic disease. 81 patients underwent open and 69 patients underwent laparoscopic distal pancreatectomy (LDP) Intra-operative estimated blood loss was significantly lower in the LDP group than in the OPD group (200 vs. 400 ml p<0.01). There was no difference in blood transfusion between the two groups. There was a significant difference in the resection method between the two groups (p<0.01) and there was a significant difference in the use of mesh for prevention of postoperative pancreatic fistula (POPF) (53 vs. 34 p<0.01). There was no significant difference in incidence of POPF (15.9% in LDP vs 7.4% in ODP, p=0.235) between the two groups, morbidity rate between the two groups (18 vs. 30 p=0.152), post - pancreatectomy hemorrhage, wound infection, hospital stay and readmission. CONCLUSIONS: LDP showed there was no difference in the occurrence of POPF, complication and hospital stay. In contrast, intra-operative blood loss was significantly lower in the LDP group than in the ODP group, and LDP was also significantly better in the view point of the feeding advance. In other words, LDP is safer and more favorable to patients than ODP.

The value of supply chain coordination under moral hazard: A case study of the consumer product supply chain.

In this paper, we examine a real-world case related to the consumer product supply chain to analyze the value of supply chain coordination under the condition of moral hazard. Because of the characteristics of a buyback contract scheme employed in the supply chain, the supplier company's sales department encourages retailers to order more inventory to meet their sales target, whereas retailers pay less attention to their inventory level and leftovers at the end of the season. This condition induces moral hazard problems in the operation of the supply chain, as suppliers suffer from huge returns of leftover inventory. This, in turn, is related to the obsolescence of returned inventory, even with penalty terms in the contract for the return of any leftovers. In this study, we show under the current buyback-based supply chain operation, the inventory levels of both the supplier and retailers exceed customer demand and develop vendor-managed inventory (VMI) system with base stock policy to remove any mismatch of supply and demand. A comparison of both systems shows that through the proper coordination of supply chain operations, both suppliers and retailers can gain additional benefits while providing proper services to end customers.

Accounting for Fairness in a Two-Stage Stochastic Programming Model for Kidney Exchange Programs.

Kidney exchange programs, which allow a potential living donor whose kidney is incompatible with his or her intended recipient to donate a kidney to another patient in return for a kidney that is compatible for their intended recipient, usually aims to maximize the number of possible kidney exchanges or the total utility of the program. However, the fairness of these exchanges is an issue that has often been ignored. In this paper, as a way to overcome the problems arising in previous studies, we take fairness to be the degree to which individual patient-donor pairs feel satisfied, rather than the extent to which the exchange increases social benefits. A kidney exchange has to occur on the basis of the value of the kidneys themselves because the process is similar to bartering. If the matched kidneys are not of the level expected by the patient-donor pairs involved, the match may break and the kidney exchange transplantation may fail. This study attempts to classify possible scenarios for such failures and incorporate these into a stochastic programming framework. We apply a two-stage stochastic programming method using total utility in the first stage and the sum of the penalties for failure in the second stage when an exceptional event occurs. Computational results are provided to demonstrate the improvement of the proposed model compared to that of previous deterministic models.