Intracorporeal Vessel Ligation in Laparoscopic Right Colectomy for Cancer is Associated with Increased Lymph Node Yield.

BACKGROUND: This study aimed to compare intra- and extracorporeal division of the vascular pedicle in laparoscopic right colectomy regarding pathological outcomes, short-term morbidity, and local recurrence and distant metastases. METHODS: Retrospective analysis of an IRB-approved database of all patients who underwent laparoscopic right colectomy for cancer between 01/2011 and 08/2021. Main outcome measures were number of harvested lymph nodes, length of resected colon, R1 rate, positive lymph node ratio, short-term post-operative morbidity, local recurrence, and distant metastases. RESULTS: Two-hundred seventy-one consecutive patients (136 males) patients underwent laparoscopic right hemicolectomy for cancer during the study period. Vessel ligation was intracorporeal in 171 (63%) and extracorporeal in 100 patients (37%); groups had similar baseline characteristics except for extent of resection as extended right hemicolectomy was significantly more often performed in the intracorporeal group. When the two groups were matched for the extent of resection (standard versus extended right hemicolectomy), the mean number of harvested lymph nodes (28.61 ± 12.04 versus 25.37 ± 10.06, p = 0.04) and median length of the resected colon [26.00 (IQR: 21.00, 32.00) versus 23.00 (IQR: 19.00, 27.00) cm, p = 0.003] were significantly higher in the intracorporeal than in the extracorporeal group. The intracorporeal group required a significantly longer operative time than did the extracorporeal group (168.94 ± 57.9 vs. 139.7 ± 41.3 mins, p = 0.001). No significant differences were noted between the groups in terms of ileus, hemorrhage, surgical site infection, re-operation rates, recurrence, or distant metastases. CONCLUSION: Intracorporeal vessel ligation in laparoscopic right hemicolectomy was associated with increased lymph node yield and longer specimens, although requiring longer operative times. Postoperative clinical outcomes were similar to outcomes in the extracorporeal ligation group.

Staphylococcus aureus alpha toxin activates Notch in vascular cells.

Staphylococcus aureus infection is one of the leading causes of morbidity in hospitalized patients in the United States, an effect compounded by increasing antibiotic resistance. The secreted agent hemolysin alpha toxin (Hla) requires the receptor A Disintegrin And Metalloproteinase domain-containing protein 10 (ADAM10) to mediate its toxic effects. We hypothesized that these effects are in part regulated by Notch signaling, for which ADAM10 activation is essential. Notch proteins function in developmental and pathological angiogenesis via the modulation of key pathways in endothelial and perivascular cells. Thus, we hypothesized that Hla would activate Notch in vascular cells. Human umbilical vein endothelial cells were treated with recombinant Hla (rHla), Hla-H35L (genetically inactivated Hla), or Hank's solution (HBSS), and probed by different methods. Luciferase assays showed that Hla (0.01 µg/mL) increased Notch activation by 1.75 ± 0.5-fold as compared to HBSS controls (p < 0.05), whereas Hla-H35L had no effect. Immunocytochemistry and Western blotting confirmed these findings and revealed that ADAM10 and γ-secretase are required for Notch activation after inhibitor and siRNA assays. Retinal EC in mice engineered to express yellow fluorescent protein (YFP) upon Notch activation demonstrated significantly greater YFP intensity after Hla injection than controls. Aortic rings from Notch reporter mice embedded in matrix and incubated with rHla or Hla-H35L demonstrate increased Notch activation occurs at tip cells during sprouting. These mice also had higher skin YFP intensity and area of expression after subcutaneous inoculation of S. aureus expressing Hla than a strain lacking Hla in both EC and pericytes assessed by microscopy. Human liver displayed strikingly higher Notch expression in EC and pericytes during S. aureus infection by immunohistochemistry than tissues from uninfected patients. In sum, our results demonstrate that the S. aureus toxin Hla can potently activate Notch in vascular cells, an effect which may contribute to the pathobiology of infection with this microorganism.

When is transanal endoscopic surgery appropriate?

Rectal cancer is a complex medical diagnosis which requires critical decision-making on the part of physician and patient. Organ preservation with local excision for early stage rectal cancer, if done under the correct circumstances, allows for oncologically sound surgery with good patient outcomes. However, locally advanced disease as well as tumor location and size can change potential long-term outcomes. This article will investigate the technical and clinical aspects of transanal surgery and the decision-making algorithms for clinicians and patients.