Robotic distal pancreas-sparing duodenectomy (duodenal sleeve resection) with transmesenteric approach: robotic approach for tumors in the third and fourth parts of the duodenum.

BACKGROUND: Minimally invasive resection of the retroperitoneal duodenum is complicated because of its anatomical location, and the proximity of the ampulla of Vater and vascular structures. Benign or indolent pathology can add complexity to operative decision-making for these already challenging surgeries, and operations associated with lower morbidity may be considered. This study describes a novel robotic transmesenteric approach to duodenal sleeve resection for non-malignant lesions. METHODS: A retrospective review was performed on a prospectively maintained institutional database between 2011 and 2021. The Da Vinci XI or SI platform (Intuitive Surgical, Sunnyvale, CA) was used in all cases. RESULTS: Critical steps in robotic sleeve duodenectomy include the following: (1) techniques for avoiding damage to the ampulla; (2) Kocherization and reverse Kocherization; and (3) A transmesenteric approach for further mobilization of the duodenum. Nineteen patients were referred by experienced gastrointestinal endoscopists after endoscopic management was deemed unsuitable or their resections were incomplete. The histological diagnoses were either symptomatic benign or indolent duodenal pathology. All 19 patients underwent robotic duodenal sleeve resection during the study period. Lesions were located in the third to fourth parts of the duodenum. The median operative time was 216 min (IQR: 199-225), and the estimated intraoperative blood loss was 50 ml (IQR: 50.0-93.7). The 90 day readmission rate was 15.7% (3/19), and no 90-day mortality was observed. CONCLUSION: This small case series of a transmesenteric approach for robotic sleeve duodenectomy demonstrates its feasibility and safety in this potentially challenging operation.

Total compared with partial pancreatectomy for pancreatic adenocarcinoma: assessment of resection margin, readmission rate, and survival from the U.S. National Cancer Database.

Introduction: Total pancreatectomy for pancreatic ductal adenocarcinoma has historically been associated with substantial patient morbidity and mortality. Given advancements in perioperative and postoperative care, evaluation of the surgical treatment options for pancreatic adenocarcinoma should consider patient outcomes and long-term survival for total pancreatectomy compared with partial pancreatectomy. Methods: The U.S. National Cancer Database was queried for patients undergoing total pancreatectomy or partial pancreatectomy for pancreatic adenocarcinoma during 1998-2006. Demographics, tumour characteristics, operative outcomes, 30-day mortality, 30-day readmission, additional treatment, and Kaplan-Meier survival curves were compared. Results: The database query returned 807 patients who underwent total pancreatectomy and 5840 who underwent partial pancreatectomy. More patients who underwent total pancreatectomy than a partial pancreatectomy had a margin-negative resection (p < 0.0001). Mortality and readmission rates were similar in the two groups, as was long-term survival on Kaplan-Meier curves (p = 0.377). A statistically significant difference in the rate of surgery only (without additional treatment) was observed for patients in the total pancreatectomy group (p = 0.0003). Conclusions: Although total compared with partial pancreatectomy was associated with a higher rate of margin-negative resection, median survival was not significantly different for patients undergoing either procedure. Patients who underwent total pancreatectomy were significantly less likely to receive adjuvant therapy.

Single-stage resection and microwave ablation for bilobar colorectal liver metastases.

BACKGROUND: Patients undergoing liver resection combined with microwave ablation (MWA) for bilobar colorectal metastasis may have similar overall survival to patients who undergo two-stage hepatectomy, but with less morbidity. METHODS: This was a multi-institutional evaluation of patients who underwent MWA between 2003 and 2012. Morbidity (90-day) and mortality were compared between patients who had MWA alone and those who underwent combined resection and MWA (CRA). Mortality and overall survival after CRA were compared with published data on two-stage resections. RESULTS: Some 201 patients with bilobar colorectal liver metastasis treated with MWA from four high-volume institutions were evaluated (100 MWA alone, 101 CRA). Patients who had MWA alone were older, but the groups were otherwise well matched demographically. The tumour burden was higher in the CRA group (mean number of lesions 3·9 versus 2·2; P = 0·003). Overall (31·7 versus 15·0 per cent; P = 0·006) and high-grade (13·9 versus 5·0 per cent; P = 0·030) complication rates were higher in the CRA group. Median overall survival was slightly shorter in the CRA group (38·4 versus 42·2 months; P = 0·132) but disease-free survival was similar (10·1 versus 9·3 months; P = 0·525). The morbidity and mortality of CRA compared favourably with rates in the existing literature on two-stage resection, and survival data were similar. CONCLUSION: Single-stage hepatectomy and MWA resulted in survival similar to that following two-stage hepatectomy, with less overall morbidity.

Robotic pancreaticoduodenectomy: comparison of complications and cost to the open approach.

BACKGROUND: Robotic pancreaticoduodenectomy (RP) has shown some advantages over open pancreaticoduodenectomy (OP) but no data has been published providing a cost comparison. METHODS: Retrospective analysis of all pancreaticoduodenectomies at a single quaternary cancer referral center was performed. Patient demographics, comorbidities, operative characteristics, complications, and charge data were recorded, and then compared using standard statistical methods. RESULTS: 71 pancreaticoduodenectomies were performed: 22 RP and 49 OP. Patients undergoing OP had similar demographics, comorbidities, pathology, and oncologic characteristics as patients undergoing RP. While operative charges were higher for RP, once inpatient stay associated costs and follow-up costs were included, there was no difference in total costs between RP and OP. CONCLUSIONS: Patients undergoing RP have equivalent rates of R0 resection as OP, and benefit from decreased number of complications, surgical site infections, and length of stay in the intensive care unit. Once cost of complications and follow-up are incorporated, no significant difference between procedures exists. Copyright © 2015 John Wiley & Sons, Ltd.

Evaluation of absorbable and permanent mesh fixation devices: adhesion formation and mechanical strength.

PURPOSE: Laparoscopic ventral hernia repair is commonly performed with mesh prostheses; however, there is no standard for fixation devices used to secure mesh to the abdominal wall. This study is a functional comparison of novel, screw-type absorbable and permanent fixation devices with a traditional titanium fixation device. METHODS: Fifteen pigs each underwent the laparoscopic placement of two 11 × 14-cm mesh prostheses and were randomized for mesh fixation with either titanium spiral tacks (TS), absorbable screw-type fasteners (SF), or permanent screw-type fasteners (PF) (n = 10 mesh prostheses for each fixation group). Adhesions were assessed laparoscopically at 4 weeks. The fixation devices were also embedded in porcine abdominal rectus muscle for ex vivo mechanical testing along with partial thickness polypropylene suture (PR) as a control group (n = 40 for each group). Maximum pull-off forces were measured. All statistical tests were two-tailed, and a P-value < 0.05 was considered to be significant. RESULTS: The mean tenacity adhesion scores were 1.40 ± 0.52 (PF), 1.7 ± 0.82 (SF), and 2.6 ± 1.07 (TS). Adhesions in the PF group were significantly less tenacious compared with the TS group (P = 0.01). Quantitative adhesion scores were not significantly different among groups. The maximum pull-off forces, measured in Newtons, were 28.61 N ± 4.89 N (TS), 22.71 N ± 7.86 N (SF), 16.98 N ± 7.59 N (PF), and 20.83 N ± 6.25 N (PR). The pull-off force in the TS group was higher than all of the other groups (P < 0.001). The SF group also had a higher pull-off force compared with the PF group (P < 0.001). CONCLUSIONS: The screw-type absorbable and permanent fixation devices provided adequate fixation and were associated with decreased adhesions in this porcine model.

Prevalence and clinical implications of anthelmintic resistance in cyathostomes of horses.

OBJECTIVE: To determine the prevalence and clinical implications of anthelmintic resistance in cyathostomes of horses. DESIGN: Prospective study. ANIMALS: 80 horses on 10 farms in a 5-county region of northeast Georgia. PROCEDURE: On each farm, horses were stratified in descending order according to pretreatment fecal egg count (FEC), blocked into groups of 4, and then randomly assigned to 1 of 4 treatment groups: no treatment (controls), and treatment with pyrantel pamoate, fenbendazole, or ivermectin. Fecal samples were collected 24 hours prior to treatment and 2, 4, and 6 weeks after treatment for determination of FEC. Mean percentage of reduction in FEC was then calculated for each treatment group. For horses from each farm, the efficacy of each anthelmintic was categorized on the basis of mean percentage of reduction in FEC at 2 weeks after treatment (< 80% reduction = ineffective; 80 to 90% reduction = equivocal; and > 90% reduction = effective). RESULTS: Pyrantel pamoate was effective at reducing FEC in horses from 7 farms, ineffective in horses from 2 farms, and equivocal in horses from 1 farm. Fenbendazole was ineffective at reducing FEC in horses from 9 farms and equivocal in horses from 1 farm. Ivermectin was effective at reducing FEC in horses from all 10 farms. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cyathostome resistance to fenbendazole is highly prevalent, and resistance to pyrantel pamoate is high enough to warrant concern. Resistance to ivermectin was not detected. On the basis of these data, it appears that ivermectin continues to be fully effective in horses. However, too few farms were used in this study to determine the prevalence of cyathostome resistance to ivermectin. Therefore, the efficacy of ivermectin should continue to be monitored closely.

In situ expression of platelet-derived growth factor (PDGF-beta) during chronic rejection is abolished by retransplantation.

We have shown that Fischer 344-->Lewis renal allografts (ALLO) develop chronic rejection which is not detected in Lewis-->Lewis isografts (ISO). The progression of chronic rejection in ALLO can be reversed by retransplantation (RE-TX) of kidneys from ALLO back into syngeneic Fischer 344 recipients. The purpose of this study was to assess the in situ expression of PDGF-beta, a cytokine associated with wound injury, in ISO, ALLO, and RE-TX. In situ PDGF-beta mRNA expression in kidney sections was assessed early (8 weeks) and late (16 weeks) during the development of chronic rejection. Kidneys from ALLO were transplanted back into syngeneic Fischer recipients at 12 weeks and evaluated for PDGF-beta expression 12 weeks later. Differences in glomerular staining were graded quantitatively on a minimum of 25 glomeruli per section with grade 0, no positive cells in the glomerulus; grade 1, 1 or 2 positive cells; grade 2, 3 or more positive cells in a segmental distribution; and grade 3, > 4 positive cells of moderate intensity in a diffuse distribution. According to this grading system, glomerular PDGF-beta mRNA expression in isografts (N = 6) at 8 and 16 weeks after transplantation was 0.09 +/- 0.03 and 0.2 +/- 0.04, respectively. In allografts (N = 6), PDGF-beta mRNA was significantly higher (P < .001) for the same time periods, 1.28 +/- 0.6 and 1.89 +/- 0.08, respectively. In situ expression of PDGF in retransplants (N = 6) at 24 weeks, 0.07 +/- 0.02, was significantly diminished (P < .001) at 24 weeks compared to allografts at 8 or 16 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

The pathway and targeting signal for delivery of the integral membrane glycoprotein LEP100 to lysosomes.

A complete set of chimeras was made between the lysosomal membrane glycoprotein LEP100 and the plasma membrane-directed vesicular stomatitis virus G protein, combining a glycosylated lumenal or ectodomain, a single transmembrane domain, and a cytosolic carboxyl-terminal domain. These chimeras, the parent molecules, and a truncated form of LEP100 lacking the transmembrane and cytosolic domains were expressed in mouse L cells. Only LEP100 and chimeras that included the cytosolic 11 amino acid carboxyl terminus of LEP100 were targeted to lysosomes. The other chimeras accumulated in the plasma membrane, and truncated LEP100 was secreted. Chimeras that included the extracellular domain of vesicular stomatitis G protein and the carboxyl terminus of LEP100 were targeted to lysosomes and very rapidly degraded. Therefore, in chimera-expressing cells, virtually all the chimeric molecules were newly synthesized and still in the biosynthesis and lysosomal targeting pathways. The behavior of one of these chimeras was studied in detail. After its processing in the Golgi apparatus, the chimera entered the plasma membrane/endosome compartment and rapidly cycled between the plasma membrane and endosomes before going to lysosomes. In pulse-expression experiments, a large population of chimeric molecules was observed to appear transiently in the plasma membrane by immunofluorescence microscopy. Soon after protein synthesis was inhibited, this surface population disappeared. When lysosomal proteolysis was inhibited, chimeric molecules accumulated in lysosomes. These data suggest that the plasma membrane/early endosome compartment is on the pathway to the lysosomal membrane. This explains why mutations that block endocytosis result in the accumulation of lysosomal membrane proteins in the plasma membrane.