ABSTRACT
Purpose@#The present study compares the peri/postoperative and oncological outcomes of abdominoperineal resections (APR) and sphincter saving resection (SSR) for low lying rectal cancer. @*Methods@#Between January 2001 and December 2014, 176 patients who underwent SSR (n = 67) and APR (n = 109) for low rectal cancer, without stage IV, were retrieved from a retrospective database. @*Results@#With a median follow-up of 66.5 months. The mean total number of harvested lymph nodes was 16.7 (SSR) versus 17.1 (APR) (P = 0.801). The advanced T stage was higher in the APR group (82.6%) versus the SSR group (55.2%) (P = 0.006). The positive rate of lymph nodes after surgery was significantly higher in the APR group (45.9%) versus SSR group (25.4%) (P < 0.05). The 5-year overall survival rates for SSR and APR were 87.3% and 67.6%, respectively (P < 0.005). The 5-year disease-free survival rate (DFS) was 83.6% (SSR) versus 65.5% (APR) (P = 0.002). The recurrence rate was higher in the APR group (34.9%) versus the SSR group (14.9%) (P = 0.004). Local recurrence rate was not different between the two groups. However, distant recurrence rate was significantly higher in the APR group (26.6% vs. 11.9%, P = 0.023). In multivariate analysis, node positive (N0 vs. N1-2) was an independent prognostic factor for DFS (P < 0.005). @*Conclusion@#Based on the present data, SSR achieved better 5-year oncological outcome than APR. The positive lymph node ratio in the N stage after surgery was higher in the APR group and this seems to have an effect on the oncological outcomes of the APR group.
ABSTRACT
PURPOSE: To better understand the performance of four commercially available neurovascular stents in intracranial aneurysm embolization, the stents were compared in terms of their basic morphological and mechanical properties. MATERIALS AND METHODS: Four different types of stents that are currently being used for cerebral aneurysm embolization were prepared (two stents per type). Two were laser-cut stents (Neuroform and Enterprise) and two were braided from a single nitinol wire (LEO and LVIS stents). All were subjected to quantitative measurements of stent size, pore density, metal coverage, the force needed to load, push, and deploy the stent, radial force on deployment, surface roughness, and corrosion resistance. RESULTS: Compared to their nominal diameters, all stents had greater diameters after deployment. The length generally decreased after deployment. This was particularly marked in the braided stents. The braided stents also had higher pore densities than the laser-cut stents. Metal coverage was highest in the LEO stent (14%) and lowest in the Enterprise stent (5%). The LIVS stent had the highest microcatheter loading force (81.5 gf). The LEO stent had the highest passage force (55.0 gf) and deployment force (78.9 gf). The LVIS and LEO stents had the highest perpendicular (37.1 gf) and circumferential (178.4 gf) radial forces, respectively. The Enterprise stent had the roughest stent wire, followed by the LVIS, LEO, and Neuroform stents. CONCLUSION: The four neurovascular stent types differed in terms of morphological and physical characteristics. An understanding of this diversity may help to decide which stent is most suitable for specific clinical situations.