Hiroshi Asano

LYMPHATIC INJURY AND REGENERATION IN CARDIAC ALLOGRAFTS

Background. Severed donor heart lymphatics are not anastomosed to recipient lymphatics in cardiac transplantation. We evaluated the effects of cellular infiltrates of T cells and macrophages on the morphology of lymphatics in heart grafts. Methods. Dark agouti hearts were transplanted to Lewis or control dark agouti rats on subtherapeutic doses of cyclosporin. Transplants were examined by immunohistology and quantitative immunofluorescence microscopy using lymphatic endothelial hyaluronan receptor-1 as a lymphatic marker and CD8 and CD68 as markers for cellular infiltration at selected intervals from 1 to 8 weeks posttransplantation. Results. Allograft inner myocardial lymphatic density decreased by more than 30-fold at 1 week and recovered to only 15% of the native level at 8 weeks posttransplantation. In contrast, allograft lymphatics in and near the epicardium showed no significant density decline but increased in size by more than 5-fold at 2 weeks, and sustained approximately 3-fold increase at 8 weeks posttransplantation. Lymphatic changes correlated temporally with the extent of T cell and macrophage infiltration in allografts, which peaked at 2 to 3 weeks posttransplantation. When grafts were retransplanted from allogeneic to isogeneic recipients at 3 weeks posttransplantation, inner lymphatic density returned close to native level within 2 weeks after retransplantation. Conclusions. This is the first characterization of regional and morphologic effects of immunologic responses on heart lymphatics after transplantation. Elimination of alloimmune responses produces rapid restoration of inner lymphatic vessels, suggesting that lymphatics injured during rejection can recover when rejection is reversed during the posttransplantation course.

Postoperative recurrence and risk factors of colorectal cancer perforation

PurposeThe common causes of colorectal perforation are benign. However, perforated colorectal cancer confers a risk of recurrence in the long term because of the malignant nature of the disease. In addition, the recurrence rate can also increase because of dissemination of cancer cells, reduced extent of lymph node dissection to prioritize saving life, and other reasons.MethodsWe evaluated the clinical features and postoperative recurrence in patients with perforated colorectal cancer who developed general peritonitis and underwent emergency surgery during a 7-year period between April 2007 and March 2014.ResultsDuring the study period, 44 patients had colorectal cancer perforation. The cancer sites were the ascending colon in 6 patients, transverse colon in 1, descending colon in 4, sigmoid colon in 15, and rectum in 18. The disease stage was stage II in 18 patients, stage III in 15, and stage IV in 7. Among 22 patients who could be followed up, 8 had postoperative recurrence. The recurrence rates were 18.2% for stage II cancer and 54.5% for stage III. Postoperative recurrence was more likely to occur in the patients positive for lymph node metastasis, those with poorly differentiated adenocarcinoma, those with T4 cancer, and those who did not receive postoperative adjuvant chemotherapy.ConclusionThe recurrence rate was higher in the patients with perforated colorectal cancer than in those who underwent surgery for common colorectal cancer. The prognosis can be expected to improve by performing standard surgical procedures, to the maximum extent possible, followed by postoperative adjuvant chemotherapy.

Mesh penetrating the cecum and bladder following inguinal hernia surgery: a case report

BackgroundTension-free repair using mesh is a common inguinal hernia surgical procedure. However, various complications such as mesh-related infection and recurrence may develop as a result. Moreover, although rare, there are also reports of intestinal obstruction caused by adhesion of the mesh to the intestinal wall and cases of mesh migration into various organs. Here, we report our experience with a patient in whom mesh extraction was performed due to migration of mesh into the intestinal tract following inguinal hernia surgery and formation of a fistula with the bladder.Case presentationOur patient was a 63-year-old Japanese man who had a history of operative treatment for right inguinal hernia during early childhood. Because a relapse subsequently occurred, he was diagnosed as having recurrent right inguinal hernia at the age of 56 years for which operative treatment (the Kugel method) was performed. He presented to our hospital 6 years later with the chief complaint of lower abdominal pain. Computed tomography findings revealed a mass shadow in contact with his bladder and cecal walls, and enteric bacteria were detected in his urine. Furthermore, because lower gastrointestinal endoscopic findings confirmed mesh in the cecum, we performed operative treatment. The mesh had migrated into the cecum and a fistula with his bladder had formed. We removed the mesh through ileocecal resection and partial cystectomy.ConclusionsIt appeared that a peritoneal defect occurred when the mesh was placed, allowing the mesh to migrate into our patient’s intestinal tract. Because contact between the mesh and the cecum resulted in inflammation, a fistula formed in his bladder. It is important to completely close the peritoneum when placing the mesh.