ABSTRACT
Mesenteric liposarcoma is a rare neoplasm. Here, we report the case of a 73-year-old Japanese man with a well-differentiated (WD) liposarcoma of the mesentery. Due to rapid growth of the abdominal mass and abdominal insufficiency, a tumorectomy was performed. The excised tumor was 12.4 × 9.6 cm in size and weighed 548 g. Cut sections showed a lobulated yellow and/or grayish-colored appearance. The histological features were predominantly those of the sclerotic and lipoma-like variants of WD liposarcoma. The cytoplasm of most spindle cells was diffusely immunoreactive for CD34, while fat cells were positive for S-100 protein. Some spindle cell nuclei were positive for CDK4, and a few were positive for MDM2. The average Ki-67 proliferation index in tumor cells was 10%, and androgen receptor expression was detected in tumor cell nuclei. The present case and 11 cases identified from a literature search were reviewed. The WD mesenteric liposarcomas developed in patients in the fourth to seventh decades of life (mean age 57.9 years). The patients consisted of 7 men and 5 women. All tumors were larger than 10 cm in diameter at the time of surgery. Complete resection might be the only curative therapy for WD liposarcomas of the mesentery, but long-term follow-up is needed because of the possibility of a local recurrence of the tumor.
ABSTRACT
We report a primary hepatic carcinoid tumor occurring in a 47-year-old man. The patient consulted our hospital complaining of epigastralgia. Abdominal ultrasonography, computed tomography scanning, and magnetic resonance imaging showed a large mass in the right lobe of the liver. FDG-PET revealed 18F-FDG uptake by the right hepatic lobe. The tumor was a solid mass with cystic components, approximately 15 cm in diameter. We conducted an extended right lobectomy of the liver. The resected specimen was a solid tumor with cystic components and hemorrhagic lesion. Microscopic findings showed that the tumor cells had round nuclei and formed trabecular patterns. Immunohistologically, tumor cells were stained positive for chromogranin A, neuron specific enolase, CD56, and S-100. Careful examinations before and after the operation revealed no other possible origin of the tumor. Based on these findings, the tumor was diagnosed as a primary hepatic carcinoid. This is a report of a rare case of a primary hepatic carcinoid tumor with a discussion of several other relevant reports.
ABSTRACT
Fibronectins (Fns) are involved in a number of biologic processes, such as cellular adhesion, motility, differentiation, apoptosis, hemostasis, wound healing, and ischemic injury. We investigated the possible mechanism underlying the protective action of plasma Fn (pFn) on endotoxin shock following partial hepatectomy in rats. Lipopolysaccharide (LPS) was administered intravenously to male Sprague-Dawley rats within 48 hrs of 70% hepatectomy. Prior to LPS administration, pFn or human serum albumin was given intravenously. The survival rate of the pFn-treated group was improved markedly compared with that of the controls. The levels of inflammatory cytokines and nitric oxide (NO) in serum were significantly lower in the pFn-treated group than in the control group. Expression of inducible nitric oxide synthase (iNOS) in hepatocytes also was reduced following pFn treatment. The degree of apoptosis and necrosis in the remnant liver was significantly lower in the pFn-treated rats than the controls. Furthermore, pFn pretreatment greatly inhibited the activation of nuclear factor-kappaB (NF-kappaB), caspase 3 and 8 activities, and cytochrome c release, and caused a decrease in mitochondrial Bcl-x(L). Plasma Fn prevents endotoxin-induced liver injury at least in part through inhibition of NF-kappaB activation, which causes the reduction of iNOS expression and NO production by hepatocytes, and through the downregulation of inflammatory cytokines and promotion of Bcl-x(L) expression.
