Prognostic Impact of Intra-Ampullary Papillary-Tubular Neoplasm versus Flat Dysplasia as Precursor Lesions of Ampullary Adenocarcinoma.

BACKGROUND: The aim of this study is to compare the prognostic impact of 2 precursor lesions of ampullary adenocarcinoma, intra-ampullary papillary-tubular neoplasm (IAPN) and flat dysplasia (FD). METHODS: From December 1994 to December 2012, a total of 359 patients underwent curative surgery for ampullary adenocarcinoma. RESULTS: The precursor lesions were IAPNs in 134 (37.3%) patients and FD in the other 225 (62.7%) patients. The FD group had more aggressive tumor biology with advanced T stage (p = 0.002), nodal involvement (p < 0.001), poor differentiation (p < 0.001), perineural and lymphovascular invasion (p < 0.001), and pancreatobiliary or mixed subtype (p < 0.001). Five-year overall survival rates were 71.1% in the IAPN group and 51.4% in the FD group (p = 0.002), respectively. Five-year disease-free survival rates were 69.7% in the IAPN group and 49.6% in the FD group (p < 0.001), respectively. The recurrence rate was also higher in the FD group (49.8 vs. 30.6%; p < 0.001). On multivariate analysis, higher levels of tumor markers including CEA and CA19-9, lymph node metastasis, poorly differentiated histology, and perineural invasion were negative predictive factors for survival. Higher levels of CEA and CA19-9, lymphovascular invasion, and FD were independent prognostic factors for recurrence. CONCLUSION: FD was significantly associated with worse prognosis and a greater tendency toward advanced disease. Further studies are needed to clarify the impacts of these precursor lesions.

Neoadjuvant therapy versus upfront surgery for borderline-resectable pancreatic cancer.

BACKGROUND: Neoadjuvant therapy is recommended for patients with borderline-resectable pancreatic cancer (BRPC). In this study, we compare survival outcomes of neoadjuvant therapy with upfront surgery. METHODS: From January 2011 to June 2016, 1415 patients underwent treatments for pancreatic cancer in Samsung Medical Center. Among them, 112 (7.9%) patients were categorized as BRPC by the NCCN 2016 guideline. They were classified by type of initial treatments into neoadjuvant group (NA, N.=26) and upfront surgery group (US, N.=86). RESULTS: The median survival duration of all patients was 18.3 months. Patients in the NA group had more T4 disease than those in the US group (38.5% in NA versus 15.1% in the US group; P=0.010). Arterial involvement was more frequent in the NA group (42.3% versus 15.1%; P=0.003). In the NA group, ten (38.5%) patients underwent surgery, and seven of them had complete R0 resection. In the US group, 83 (96.5%) patients received radical surgery, and 42 (48.8%) had R0 resection. In survival analysis according to intent to treat, the overall two-year survival rate was 51.1% in the US group and 36.7% in the NA group (P=0.001). However, among patients who underwent surgery (N.=96), the two-year overall survival rate was not significantly different between the two groups (P=0.089). According to involved vessels, the survival rate was not different between patients with arterial or both arterial and venous involvement and in patients with only venous involvement (P=0.649). CONCLUSIONS: It is necessary to demonstrate the efficacy of neoadjuvant therapy and to standardize the regimens through large-scale, multicenter, randomized controlled studies.

Lower Extremity Arterial Bypass with Arm Vein Conduits and Literature Review.

PURPOSE: The superiority of autogenous vein conduits is well known in lower extremity arterial bypass (LEAB). Among various alternative conduits for LEAB, long-term results of arm vein grafts were investigated in this study. MATERIALS AND METHODS: We retrospectively reviewed clinical characteristics of 28 patients who underwent infrainguinal LEAB with autogenous arm vein grafts at a single institute between January 2003 and December 2015. All procedures were performed in the absence of adequate saphenous veins. Graft patency was determined by periodic examinations with duplex ultrasonography. RESULTS: Autologous arm vein grafts were implanted for 28 patients (mean age, 60.4±16.8 years; range, 20-82 years; male, 92.9%; atherosclerosis, 19 [67.9%]; and non-atherosclerotic disease 9 [32.1%] including 5 patients with Buerger's disease). Source of arm vein were basilic 13 (46.4%), cephalic 4 (14.3%) and composition graft with other veins in 11 (39.3%) cases. The level of distal anastomosis was distributed as popliteal in 5 (17.9%), tibio-peroneal in 21 (75.0%) and inframalleolar artery in 2 (7.1%) cases. Mean duration of follow-up was 41.5±46.9 months (range, 1-138 months). Cumulative primary patency rates at 1, 3, and 5 years were 66.5%, 60.9% and 60.9%, respectively. Assisted-primary patency rates at 1, 3 and 5 years were 66.5%, 66.5% and 66.5%, respectively. Secondary patency rates at 1, 3 and 5 years were 70.8%, 70.8% and 70.8%, respectively. There was one limb amputation during the follow-up period. CONCLUSION: Arm veins are a useful alternative conduit when great saphenous veins are not available during LEAB.

Fabrication and Optimization of a Nanoporous Platinum Electrode and a Non-enzymatic Glucose Micro-sensor on Silicon.

In this paper, optimal conditions for fabrication of nanoporous platinum (Pt) were investigated in order to use it as a sensitive sensing electrode for silicon CMOS integrable non-enzymatic glucose micro-sensor applications. Applied charges, voltages, and temperatures were varied during the electroplating of Pt into the formed nonionic surfactant C16EO8 nano-scaled molds in order to fabricate nanoporous Pt electrodes with large surface roughness factor (RF), uniformity, and reproducibility. The fabricated nanoporous Pt electrodes were characterized using atomic force microscopy (AFM) and electrochemical cyclic voltammograms. Optimal electroplating conditions were determined to be an applied charge of 35 mC/mm2, a voltage of -0.12 V, and a temperature of 25 °C, respectively. The optimized nanoporous Pt electrode had an electrochemical RF of 375 and excellent reproducibility. The optimized nanoporous Pt electrode was applied to fabricate non-enzymatic glucose micro-sensor with three electrode systems. The fabricated sensor had a size of 3 mm x 3 mm, air gap of 10 µm, working electrode (WE) area of 4.4 mm2, and sensitivity of 37.5 µA•L/mmol•cm2. In addition, it showed large detection range from 0.05 to 30 mmolL-1 and stable recovery responsive to the step changes in glucose concentration.