ABSTRACT
Background/Aims@#The use of a self-expandable metal stent (SEMS) is recommended for unresectable malignant biliary obstruction (MBO). Stent-related adverse events might differ according to the position of the stent through the ampulla of Vater (AOV). We retrospectively evaluated SEMS patency and adverse events according to the position of the SEMS. @*Methods@#In total, 280 patients who underwent endoscopic SEMS placement due to malignant distal biliary obstruction were analyzed retrospectively. Suprapapillary and transpapillary SEMS insertions were performed on 51 patients and 229 patients, respectively. @*Results@#Between the suprapapillary group (SPG) and transpapillary group (TPG), the stent patency period was not significantly different (median [95% confidence interval]: 107 days [82.3 to 131.7] vs 120 days [99.3 to 140.7], p=0.559). There was also no significant difference in the rate of adverse events. In subgroup analysis, the stent patency for an MBO located within 2 cm from the AOV was found to be significantly shorter than that for an MBO located more than 2 cm from the AOV in the SPG (64 days [0 to 160.4] vs 127 days [82.0 to 171.9], p<0.001) and TPG (87 days [52.5 to 121.5] vs 130 [97.0 to 162.9], p<0.001). Patients with an MBO located within 2 cm from the AOV in both groups had a higher percentage of duodenal invasion (SPG: 40.0% vs 4.9%, p=0.002; TPG: 28.6% vs 2.9%, p<0.001) than patients with an MBO located more than 2 cm from the AOV. @*Conclusions@#The SPG and TPG showed similar results in terms of stent patency and rate of adverse events. However, patients with an MBO located within 2 cm from the AOV had a higher percentage of duodenal invasion with shorter stent patency than those with an MBO located more than 2 cm from the AOV, regardless of stent position.
ABSTRACT
Background/Aims@#Controversy regarding the effectiveness of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma (PDAC) still exists. Here, we aimed to identify the potential benefits of neoadjuvant therapy followed by surgery for resectable PDAC. @*Methods@#We reviewed radiologically resectable PDAC patients who received resection with curative intent at a tertiary hospital in South Korea between January 2012 and August 2019. A total of 202 patients underwent curative resection for resectable PDAC: 167 underwent surgical resection first during this period, and 35 received neoadjuvant chemotherapy/chemoradiation therapy followed by surgery. Resectable PDAC patients were subdivided, and 1:3 propensity score matching (PSM) was performed to reduce selection bias. @*Results@#Compared with the group that received surgery first, the group that received neoadjuvant treatment followed by surgery had significantly smaller tumors (22.0 mm vs 27.0 mm, p=0.004), a smaller proportion of patients with postoperative pathologic T stage (p=0.026), a smaller proportion of patients with lymphovascular invasion (20.0% vs 40.7%, p=0.022), and a larger proportion of patients with negative resection margins (74.3% vs 51.5%, p=0.049). After PSM, the group that received neoadjuvant therapy had a significantly longer progression-free survival than those in the group that underwent surgery first (29.6 months vs 15.1 months, p=0.002). Overall survival was not significantly different between the two groups after PSM analysis. @*Conclusions@#We observed significantly better surgical outcomes and progression-free survival with the addition of neoadjuvant therapy to the management of resectable PDAC. However, despite PSM, there was still selection bias due to the use of different regimens between the groups receiving surgery first and neoadjuvant therapy. Large homogeneous samples are needed in the future prospective studies.
ABSTRACT
Purpose@#The current drain tubes for preventing surgically biliary anastomotic stricture are not naturally and easily removed. If a drain tube using biodegradable material is easily available and the degradation time of the tube is well controlled, surgical anastomotic stricture and fibrosis could be prevented. The aim of this animal study was to evaluate the preventive effect of novel biodegradable stents (BS) on biliary stricture and fibrosis after duct-to-duct (DD) biliary anastomosis. @*Methods@#Ten mini-pigs were allocated to the control group (n = 5) and or the stent group (n = 5). The common bile duct was exposed through surgical laparotomy and then resected transversely. In the stent group, a 4-mm or 6-mm polydioxanone/ magnesium sheath-core BS was inserted according to the width of the bile duct, followed by DD biliary anastomosis. In the control group, DD biliary anastomosis was performed without BS insertion. @*Results@#In the stent group, stents were observed without deformity for up to 4 weeks in all animals. Eight weeks later, histopathologic examination revealed that the common bile duct of the anastomosis site was relatively narrower in circumference in the control group compared to the stent group. The degree of fibrosis in the control group was more marked than in the stent group (3.84 mm vs. 0.68 mm, respectively; P < 0.05). @*Conclusion@#Our study showed that novel BS maintained their original shape and radial force for an adequate time and then disappeared without adverse events. The BS could prevent postoperative complications and strictures after DD biliary anastomosis.
ABSTRACT
Pancreatic neuroendocrine tumor (PNET) refer to tumors originating from the islet of Langerhans and shows various prognosis based on the presence or absence of symptoms due to hormone secretion, the Ki-67 cell proliferation index, and the histologic grade, and according to the degree of disease progression defined by the tumor-node-metastasis (TNM) stage classification. The purpose of medical treatment for PNET is to control symptoms or inhibit tumor growth. Somatostatin analogues can be administered for the purpose of controlling symptoms caused by the secretion of specific hormones, and are accepted as effective drugs for inhibiting the progression of G1/G2 tumors based on World Health Organization (WHO) classification with a Ki-67 cell proliferation index less than 20%. Among the molecularly targeted agents, everolimus and sunitinib can be considered in patients with WHO G1/G2 PNET showing progression after somatostatin analog therapy. Cytotoxic chemotherapy is generally administered to patients with large tumor volume and rapidly progressing metastatic NET, and etoposide/cisplatin combination therapy has been considered as a standard treatment. For the patient group of Grade 3 PNET (well differentiated) newly classified by the WHO 2017 classification, guidelines for standard treatment have not yet been established. As it has been reported, studies are needed to evaluate the treatment response rate of somatostatin analogues or molecularly targeted therapies for the patient with Grade 3 PNET. It is important to consider a multidisciplinary approach with all possible treatment options including medical treatment, radical resection of primary or metastatic lesions, liver-directed therapies, and peptide receptor radionuclide therapy for the patients with PNET.
ABSTRACT
Pancreatic cancer is still one of the most aggressive malignancy, showing 10% of 5-year survival. Among the several reasons of the grave prognosis, the poor response to chemotherapeutic agents and the absence of effective tool for early detection are the most important. Regarding treatments, surgical resection is still positioned as the only one for expecting the cure of pancreatic cancer. However, the rate of recurrence after surgery is still high as more than 50%. And the portion of patients who are diagnosed at the resectable stage is still less than 15% of all cases. So, chemotherapy and radiotherapy are the main players for combating with pancreatic cancer. After the introduction of outcomes of FOLFIRINOX, and gemcitabineabpaclitaxel for metastatic pancreatic cancer, two-digit overall survival can be expected. And, neoadjuvant treatments including concurrent chemoradiation therapy for borderline resectable pancreatic cancer and/or resectable pancreatic cancer are reported as superior to upfront surgery. More recently, several target agents including polyadenosine diphosphate-ribose polymerase inhibitors and immunologic drugs are under evaluation for pancreatic cancer. So, herein, current status of chemotherapy and radiation therapy for pancreatic cancer will be addressed.
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Background/Aims@#Sarcopenia is associated with liver fi-brosis in patients with nonalcoholic fatty liver disease and chronic hepatitis B. We investigated the association between sarcopenia and hepatic fibrotic burden in patients with type 2 diabetes mellitus (T2DM). @*Methods@#Patients with T2DM who had received a comprehensive medical health checkup were recruited. Muscle mass was assessed using com-puted tomography. Fibrotic burden was assessed using the fibrosis-4 index (FIB-4). The study population was divided by quartile stratification of the lumbar skeletal muscle index (LSMI). @*Results@#Among 309 patients with T2DM, 75 (24.3%) had sarcopenia. These patients were significantly older and had higher FIB-4, whereas they had significantly lower body mass index (BMI) and LSMI than patients without sarcopenia (all p<0.05). The LSMI showed a significant negative cor-relation with the FIB-4 when analyzed in terms of quartile stratification (p=0.003). Multivariate analysis showed that female sex and higher BMI were independently associated with a reduced risk of sarcopenia (odds ratio [OR], 0.388;95% confidence interval [CI], 0.199 to 0.755 and OR, 0.704;95% CI, 0.618 to 0.801; all p<0.05), whereas a higher FIB-4 was independently associated with an increased risk of sarcopenia (OR, 1.817; 95% CI, 1.180 to 2.797; p=0.007).Among patients with a BMI <25 kg/m 2 (n=165), those with sarcopenia (n=54, 32.7%) had a significantly higher FIB-4 than those without (n=111, 67.3%; 1.66 vs 1.38, p=0.004). @*Conclusions@#Sarcopenia is independently associated with fibrotic burden in patients with T2DM. Further studies should investigate whether the improvement of sarcopenia can ameliorate liver fibrosis in patients with T2DM.