Objective: To investigate radial margin (RM) status in resected perihilar cholangiocarcinoma (PHCC) and to evaluate the incidence of positive RM and its effect on survival. Background: Although numerous studies have reported on ductal margin (DM) status in resected PHCC, no studies have addressed RM status. Methods: Patients who underwent hepatectomy for PHCC between 2001 and 2014 were retrospectively reviewed. After formalin fixation, resected specimens were serially sectioned at 5-mm intervals. All serial sections were color-copied, and RMs and DMs were identified and indicated on the color copies. Results: Among 478 patients, 85 (17.8%) had positive surgical margins (R1 resection); of the 85 patients, 37 had positive RM alone, 33 had positive DM alone, and the remaining 15 had both positive RM and positive DM. Overall, 52 (61.2%) patients had positive RM. The sites of positive RM included the liver transection plane (n = 20) and the dissection plane in the hepatoduodenal ligament (n = 32). RM positivity on the liver transection plane was higher in left hepatectomy than in other hepatectomies (9.2% vs 1.9%, P < 0.001). RM positivity in the hepatoduodenal ligament was higher in left-sided hepatectomy than in right-sided hepatectomy (8.7% vs 3.6%, P = 0.031). The survival of the patients with positive RM was poorer than that of R0 patients (MST 2.1 vs 4.9 yrs, P < 0.001) and was similar to that of patients with positive DM. Multivariate analysis identified positive RM as one of the independent prognostic factors. Conclusions: Positive RM was the most common cause of R1 resection of PHCC and had similarly negative effects on survival as positive DM. Meticulous handling of the resected specimen is important to accurately evaluate RM status together with DM status.
Homing of osteogenic cells through the systemic circulation represents an alternative to traditional orthopedic tissue engineering approaches that focus on local cell populations. We hypothesize that expression of the chemokine, stromal cell-derived factor-1 (SDF-1) or monocyte chemotactic protein-3 (MCP-3) may enhance homing of osteogenic cells into sites of fracture repair, as both have demonstrated promise in recruitment of marrow stromal cells (MSCs). This hypothesis was tested by transplantation of culture expanded MSCs expressing these factors adjacent to a fracture site on a collagen scaffold. One green fluorescent protein positive (GFP þ ) and one wild-type mouse were surgically conjoined as parabiots at 7-8 weeks of age. Fibular osteotomy was performed 4 weeks after parabiosis on the hind limb of the wild-type mouse. Mice were randomly allocated to receive one of the following five treatments: control (no scaffold), empty scaffold (no cells), or scaffold containing MSCs, scaffold containing MSCs expressing SDF-1, or scaffold containing MSCs expressing MCP-3. Fracture callus was harvested 2 weeks after injury, and analyzed with confocal microscopy and cell-counting software. When compared to fracture callus treated with nontransfected MSCs, the fracture callus of mice treated with both SDF-1 and MCP-3 secreting MSCs demonstrated a significant increase in the number of both GFPThese data suggest that homing of osteogenic cells from systemic circulation participate in fracture repair and that homing pathways might be modulated to enhance the contribution of circulating progenitors at the site of skeletal injury. ß
Background: The T system for distal cholangiocarcinoma has been revised from a layer-based to a depth-based approach in the current American Joint Committee on Cancer (AJCC) classification. In perihilar cholangiocarcinoma, tumour depth in the staging scheme has not yet been addressed. The aim of this study was to propose a new T system using measured tumour depth in perihilar cholangiocarcinoma.Methods: Patients who underwent hepatectomy for perihilar cholangiocarcinoma between 2001 and 2014 were reviewed retrospectively. The vertical distance between the top of the tumour and deepest invasive cells was measured as invasive tumour thickness (ITT) by two independent pathologists. Log rank statistics were used to determine cut-off points, and the concordance (C) index was used to assess survival discrimination of each T system. Results: ITT was measurable in all 440 patients, with a median value of 6⋅0 (range 0-45) mm. The median difference in ITT between observers was 0⋅6 (range 0-20) mm. Cut-off points for prognosis were 1, 5 and 8 mm. Five-year survival decreased with increasing ITT (P < 0⋅001): 67 per cent for ITT less than 1 mm (25 patients), 54⋅9 per cent for ITT 1 mm and over to less than 5 mm (138 patients), 43⋅4 per cent for ITT 5 mm and over to less than 8 mm (118 patients), and 32⋅2 per cent for ITT 8 mm and over (159 patients). The C-index of this classification was comparable to that of the current AJCC T classification (0⋅598 versus 0⋅589).Conclusion: ITT is a reliable approach for making a depth assessment in perihilar cholangiocarcinoma. A four-tier ITT classification with cut-off points of 1, 5 and 8 mm is an adequate alternative to the current layer-based T classification.
Treatment of large segmental bone defects remains an unsolved clinical challenge, despite a wide array of existing bone graft materials. This project was designed to rapidly assess and compare promising biodegradable osteoconductive scaffolds for use in the systematic development of new bone regeneration methodologies that combine scaffolds, sources of osteogenic cells, and bioactive scaffold modifications. Promising biomaterials and scaffold fabrication methods were identified in laboratories at Rutgers, MIT, Integra Life Sciences, and Mayo Clinic. Scaffolds were fabricated from various materials, including poly(L-lactide-co-glycolide) (PLGA), poly(Llactide-co-e-caprolactone) (PLCL), tyrosine-derived polycarbonate (TyrPC), and poly(propylene fumarate) (PPF). Highly porous three-dimensional (3D) scaffolds were fabricated by 3D printing, laser stereolithography, or solvent casting followed by porogen leaching. The canine femoral multi-defect model was used to systematically compare scaffold performance and enable selection of the most promising substrate(s) on which to add cell sourcing options and bioactive surface modifications. Mineralized cancellous allograft (MCA) was used to provide a comparative reference to the current clinical standard for osteoconductive scaffolds. Percent bone volume within the defect was assessed 4 weeks after implantation using both MicroCT and limited histomorphometry. Bone formed at the periphery of all scaffolds with varying levels of radial ingrowth. MCA produced a rapid and advanced stage of bone formation and remodeling throughout the defect in 4 weeks, greatly exceeding the performance of all polymer scaffolds. Two scaffold constructs, TyrPC PL /TCP and PPF4 SLA /HA PLGA Dip , proved to be significantly better than alternative PLGA and PLCL scaffolds, justifying further development. MCA remains the current standard for osteoconductive scaffolds.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.