[A Case of Rectus Sheath Hematoma Presenting Immediately after a Lumboperitoneal Shunt and Requiring Emergency Surgery:Importance of Abdominal Anatomy Knowledge].

As the incidence of idiopathic normal-pressure hydrocephalus (iNPH) rises in an aging society, the number of cerebrospinal fluid (CSF) shunts performed increases every year. The morbidity of iNPH in patients>65 years of age has been reported as 1.4%-2.9% in Japan. CSF shunts are rarely associated with mortality and are generally safe to perform, but subcutaneous hematomas and intestinal injuries are the major potential complications of the abdominal surgery for CSF shunts. In this report, we describe an uncommon case of rectus sheath hematoma (RSH) that occurred immediately after a lumboperitoneal shunt and required emergency surgery. RSHs have a reported mortality rate of 4% and require appropriate treatment. Many neurosurgeons rarely have in-depth knowledge of abdominal anatomy. To safely perform CSF shunting, we underscore the importance of precise knowledge of the abdominal anatomy, especially the features of blood vessels.

Oncogenic PIK3CA mutations in colorectal cancers and polyps.

Oncogenic PIK3CA mutations contribute to colorectal tumorigenesis by activating AKT signaling to decrease apoptosis and increase tumor invasion. A synergistic association of PIK3CA mutation with KRAS mutation has been suggested to increase AKT signaling and resistance to antiepidermal growth factor receptor inhibitor therapy for advanced colorectal cancer, although studies have been conflicting. We sought to clarify this by examining PIK3CA mutation frequency in relation to other key molecular features of defined pathways of tumorigenesis. PIK3CA mutation was assessed by high resolution melt analysis in 829 colorectal cancer samples and 426 colorectal polyps. Mutations were independently correlated with clinicopathological features including patient age, sex and tumor location as well as molecular features including microsatellite instability, KRAS and BRAF mutation, MGMT methylation and the CpG Island Methylator Phenotype (CIMP). Mutation of the helical (Exon 9) and catalytic (Exon 20) domain mutation hotspots were also examined independently. Overall, PIK3CA mutation was positively correlated with KRAS mutation (p < 0.001), MGMT methylation (p = 0.007) and CIMP (p < 0.001). Novel, exon-specific associations linked Exon 9 mutations to a subgroup of cancers characterized by KRAS mutation, MGMT methylation and CIMP-Low, whilst Exon 20 mutations were more closely linked to features of serrated pathway tumors including BRAF mutation, microsatellite instability and CIMP-High or Low. PIK3CA mutations were uncommonly, but exclusively, seen in tubulovillous adenomas (4/124, 3.2%) and 1/4 (25.0%) tubulovillous adenomas with a focus of cancer. These data provide insight into the molecular events driving traditional versus serrated pathway tumorigenesis.

Tubular adenomas with minor villous changes show molecular features characteristic of tubulovillous adenomas.

Advanced colorectal polyps are identified based on size ≥10 mm, high-grade dysplasia, and/or villous histology. A diagnosis of tubular adenoma (TA) is recommended if villous change occupies <20% of the lesion, or tubulovillous adenoma (TVA) is recommended if there is 20% to 80% villosity. We hypothesized that even subtle villous changes (1% to 20%) would correlate with advanced molecular features. Two hundred sixty-nine colorectal adenomas were examined for KRAS and BRAF mutation and immunohistochemical staining of ß-catenin, O6-Methyl Guanine DNA Methyltransferase (MGMT), and p53. Adenomas were classified as TA1 (0% villosity, n=70), TA2 (1% to 20% villosity, n=81), or TVA (21% to 80% villosity, n=118). Clinical and molecular features were analyzed by univariate χ² and multivariate logistic regression. There was an incremental increase in KRAS mutation frequency with increasing villous compartment (17.9% TA1, 59.0% TA2, 78.4% TVA; P<0.001). MGMT was more frequently lost in TA2 (37.0%) than in TA1 (8.6%) (P<0.001) but did not differ from TVA (39.8%). p53 overexpression was more common in TA2 (38.3%) than in TA1 (10.0%) (P<0.001) but did not differ from TVA (32.2%). On multivariate analysis, TA2 adenomas were more likely to have a KRAS mutation [odds ratio (OR) 6.6, 95% confidence interval (CI), 3.0-14.2], MGMT loss (OR 6.2, 95% CI, 2.4-16.0), or p53 overexpression (OR 5.6, 95% CI, 2.3-13.7) than TA1. We have identified a subgroup of TAs based on subtle villous changes. These adenomas are more likely to show molecular features that are characteristic of TVAs than TAs. These data support the concept that any villous change may indicate increased malignant potential and may be useful to consider when assigning surveillance guidelines.

CD4 T-cell regulation of cytotoxic T cells during the induction phase of liver-induced spontaneous tolerance in rats.

PURPOSE: To check for in vivo CD4 T-cell-mediated inhibition of the immune response in rats with spontaneously accepted liver transplants. METHODS: Using the Lewis to Wistar Furth rat strain combination, we performed transient in vivo depletion of CD4 T-cells by anti-CD4 monoclonal antibodies (mAb) after liver transplantation. We used the CTL assay to detect primed T cells. We also retransplanted a grafted donor liver, parked for 3 days, into a secondary naive recipient rat. RESULTS: When Lewis rat livers were transplanted into the recipient Wistar Furth rats, the grafts suffered an early immune attack, followed by spontaneous acceptance without immunosuppression. However, giving anti-CD4 mAb to the recipients at the time of grafting prolonged the acute rejection reaction. Furthermore, giving anti-CD4 therapy on postoperative days (PODs) 21 and 35, but not on PODs 56 and 100, induced transient liver damage in recipients overcoming acute rejection. No primed T cells were detected by the CTL assay in the recipient rats within 2 months after transplantation. Meanwhile, the retransplanted liver had no ability to elicit an immune attack. CONCLUSIONS: CD4 T cells seemed to downregulate the effector function of T cells, but not T-cell proliferation in this model.

Aggressive surgery for liver metastases from gastrointestinal stromal tumors.

BACKGROUND/PURPOSE: The utility of hepatectomy for patients with metastatic liver tumors from gastrointestinal stromal tumors (GISTs) was evaluated in the present study. METHODS: Between 1989 and 2001, ten patients with liver metastases from GIST (four men and six women; age, 34-77 years) underwent hepatectomy at our hospital. All patients underwent complete resection of the primary tumor and hepatectomy with or without microwave coagulation therapy (MCT) for all detectable hepatic tumors. RESULTS: The median survival time after hepatectomy was 39 months (range, 1 to 96 months). There was one postoperative death. One patient is still alive with relapse of hepatic tumors, and the remaining eight patients died of disease (liver in six, peritoneum in one, and bone in one). Relapse of hepatic tumors occurred in seven patients. The disease-free rate after hepatectomy was 22% at 2 years and 11% at 5 years. The survival times of the four patients who received hepatic arterial chemoembolization for recurrent hepatic metastases were 7 months (still alive), 17, 23, and 28 months (average, 19 months). CONCLUSIONS: Our data suggest that aggressive surgery (hepatectomy and MCT) for all detectable hepatic tumors and hepatic arterial chemoembolization for recurrent hepatic metastases improve survival.