Intrahepatic peribiliary perivascular epithelioid cell tumor (PEComa) associated with heterotopic pancreas: A case report.

BACKGROUND: Perivascular epithelioid-cell tumor (PEComa) is a group of rare mesenchymal neoplasms that express myomelanocytic-cell markers and exhibit a wide variety of histopathological features. Although heterotopic pancreas has been reported to occur in the gastrointestinal tract, intrahepatic heterotopic pancreas has been reported only rarely. CASE PRESENTATION: We present a case of intrahepatic PEComa that showed a strong regional correlation with the presence of heterotopic pancreas. An intrahepatic tumor and biliary dilatation was incidentally discovered during a diagnostic evaluation to investigate low-back pain in a 47-year-old Japanese male. Cholangiocarcinoma was suspected and a left hemihepatectomy performed. Histological examination revealed a 3 × 3.8-mm tumor in the neighboring B2 bile duct. Histological and immunohistochemical investigations revealed the presence of a PEComa and pancreatic acini within the tumor mass. PEComa in the hepatobiliary and pancreatic regions are extremely rare. The presence of heterotopic pancreas is also relatively uncommon. CONCLUSION: The strong regional association of these 2 lesions raises the possibility of a PEComa originating from heterotopic pancreas or from an irritable response caused by heterotopic pancreas.

Successful living donor liver transplantation for classical maple syrup urine disease.

MSUD is an autosomal recessive condition characterized by a deficiency in the enzyme, BCKDH, which catalyzes the breakdown of BCAAs. If left untreated, MSUD can result in mental retardation, central nervous system disorders, and even death. Most patients with MSUD are treated with a restricted protein diet and milk from which BCAAs have been removed. LT has been shown effective in patients with MSUD. This report describes the case of a 15-month-old boy who received a liver graft from his mother. Transplantation was successful, and the patient was then able to ingest a normal diet. Despite episodes of acute rejection, chylous ascites, and high fever (40 °C), he has shown no evidence of MSUD recurrence. These findings indicate that patients with MSUD can be successfully treated by LDLT, even when the donor is a heterozygous carrier of a mutated BCKDH gene.

Malignant transformation of hepatocellular adenoma over a decade.

A 72-year-old man diagnosed with a benign hepatocellular lesion 11 years prior was referred to our hospital for an outgrowth of the tumour in liver segment 7. Extended segmentectomy was performed and the patient's postoperative course was uneventful with no recurrence for 2 years. Histopathological examination confirmed a highly differentiated hepatocellular carcinoma (HCC) coexisting with the hepatocellular adenoma (HCA), and it was suspected to have originated from the HCA. The findings from this case demonstrate that CT can be useful for detecting the transformation of HCA into HCC.

Surgery and chemotherapy for intrahepatic cholangiocarcinoma.

Cholangiocarcinoma, arising from bile duct epithelium, is categorized into intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC), including hilarcholangiocarcinoma. Recently, there has been a worldwide increase in the incidence and mortality from ICC. Complete surgical resection is the only approach to cure the patients with ICC. However, locoregional extension of these tumors is usually advanced with intrahepatic and lymph-node metastases at the time of diagnosis. Resectability rates are quite low and variable (18%-70%). The five-year survival rate after surgical resection was reported to be 20%-40%. Median survival time after ICC resection was 12-37.4 mo. Only a small number of ICC cases, accompanied with ECC, gall bladder carcinoma, and ampullary carcinoma, have been reported in the studies of chemotherapy due to the rarity of the disease. However, in some reports, significant anti-cancer effects were achieved with a response rate of up to 40% and a median survival of one year. Although recurrence rate after hepatectomy is high for the patients with ICC, the residual liver and the lung are the main sites of recurrence after tentative curative surgical resection. Several patients in our study had a long-term survival with repeated surgery and chemotherapy. Repeated surgery, combined with new effective regimens of chemotherapy, could benefit the survival of ICC patients.

Inflammatory myofibroblastic tumor (inflammatory fibrosarcoma) of the pancreas: a case report.

Inflammatory myofibroblastic tumors (inflammatory fibrosarcomas) of the pancreas are extremely rare. We report a 29-year-old woman who underwent pancreatoduodenectomy for a 6-cm tumor of the pancreas head causing obstructive jaundice. Tumor involvement was local, without apparent metastasis. The tumor was composed of proliferating fibroblastic/or myofibroblast-like spindle cells and aggregates of chronic inflammatory cells in a fibromyxoid matrix. Immunohistochemical examination demonstrated reactivity only to vimentin. This tumor has often been found in the peritoneal cavity, the retroperitoneum, or the pelvic cavity, but only very rarely in the pancreas.

Differentiation of acinar cells into acinoductular cells in regenerating rat pancreas.

BACKGROUND/AIMS: Several lines of experimental data suggest that acinar cells have the potential to differentiate into ductular-like cells, and these newly formed acinoductular cells may act as (facultative) stem cells. The purpose of this study was to test this hypothesis in a model of pancreatic regeneration in rats. METHODS: In the current study, using a 90% pancreatectomy as a rat model for pancreatic regeneration, we serially examined the pancreatic tissues in a time-dependent manner by conventional histology and immunostaining. Cell proliferation was assessed by in vivo bromodeoxyuridine (BrdU) labeling. RESULTS: By 24 h after surgery, acini showed depleted granules with more dilated lumens (acinar ectasia). By day 2, focal regions of regeneration appeared which were separated by fibrosis and composed of ductular-like cells (tubular complexes) and acinar cells with dilated lumina. Double immunofluorescent staining revealed that both amylase and CK19 were positive in the same cells localized to the focus of regeneration from the animals on day 2, the phenotype of cells from those regions apparently reverted to acinar cells, and the regions completely disappeared by day 7. By 48 h after surgery, the number of BrdU-positive cells increased 4.3-fold in ductular cells, and 2.5-fold in acinar cells compared with control tissue. CONCLUSION: Acinar cells through acinoductular metaplasia may be a source of pancreatic regeneration.

Total pancreatectomy with segmental duodenectomy for benign or low-grade malignancy tumors of the whole pancreas.

Total pancreatectomy with segmental duodenectomy including major and minor papilla and preservation of the gastroduodenal artery is performed for low-grade malignancy tumor of the whole pancreas. Reconstruction of the alimentary tract was done by end-to-end duodenoduodenostomy and end-to-side choledochoduodenostomy. This is an easy, simple, safe and function-preserving operative procedure for benign or low-grade malignancy tumors of the whole pancreas.

Intraductal papillary mucinous tumor of the pancreas in a young man: report of a case.

We report the rare case of an intraductal papillary mucinous tumor (IPMT) in a man younger than 30 years of age. The patient was admitted with upper abdominal pain and an elevated amylase level of 662 IU/l. Ultrasonography showed a cystic mass in the pancreatic body and endoscopic retrograde cholangiopancreatography (ERCP) revealed a dilated pancreatic duct with a filling defect communicating with the tumor. He was successfully treated by segmental resection, which seems to be the best surgical option for pancreatic body tumors since it results in long-term survival and preserves as much pancreatic parenchyma as possible. Nevertheless, it can only be done in the absence of additional nodules along the pancreatic duct. A pathological diagnosis of intraductal papillary adenocarcinoma of the noninvasive type was confirmed, and both stumps were free of tumor.