Chronological changes in the liver after temporary partial portal venous occlusion

AIM:To investigate time-dependent changes caused by temporal portal vein obstruction and subsequent reperfusion in the lobe with or without an occluded portal vein.METHODS:The portal vein(PV)of the anterior lobe of the liver of a male Wistar rat(8 wk-old)was obstructed(70%)for 12,24,36 and 48 h,respectively,and models were sacrificed at 48 h after reperfusion(each group:n=10).The histological changes and the status of liver regeneration were compared between a liver biopsy performed on each lobe after temporary obstruction of the portal vein in the same rat liver,and the liver extracted at the time of sacrifice(48 h after reperfusion).RESULTS:With regard to the obstructed lobe,the liver weight/body weight ratio significantly decreased according to obstruction time.On the other hand,in thenon-obstructed lobe,there were no significant differences within each group.The duration of PV occlusion did not seem to be strong enough to introduce liver weight increase.Stimulation of liver regeneration was brought about in the non-occluded lobe by 12-h occlusion,and was sustained even at 48 h after reperfusion.The obstructed lobe atrophied with the passage of time in the obstructed state.However,the proliferating-cell nuclear antigen labeling index also increased at 48 h after reperfusion,and a repair mechanism was observed.CONCLUSION:Temporary blood flow obstruction of the portal vein may become a significant trigger for liver regeneration,even with an obstruction of 12 h.

Solitary recurrence of hilar cholangiocarcinoma in a mediastinai lymph node two years after curative resection

We recently encountered an unusual case of hilar cholangiocarcinoma in which a solitary recurrence in a mediastinal lymph node occurred two years after curative resection of the primary tumor. A 64-year old woman was admitted to our hospital with a complaint of right hypochondrial discomfort. After imaging studies demonstrated a hilar cholangiocarcinoma in the left hepatic duct, a curative resection of the tumor was performed, consisting of a left hepatic lobectomy along with caudate lobectomy, regional lymph node dissection, and resection of the extrahepatic bile duct. No nodal metastasis was observed histologically. Two years after surgery, the patient was found to have a nodule in the posterior mediastinum, which was thoracoscopically resected. No other swollen lymph nodes, local recurrence, or distant metastasis were noted. Histologically, the nodule proved to be a metastatic lymph node, and adjuvant chemoradiation therapy was initiated. The patient remained well for the four years following her first operation and had no evidence of disease recurrence 28 mo after her second operation. To our knowledge, this case is the first report of solitary recurrence in a mediastinal lymph node after curative resection of hilar cholangiocarcinoma.

Destructive granuloma derived from a liver cyst: A case report

We herein report the case of an idiopathic liver cystic mass which aggressively infiltrated the thoracoabdominal wall. A 74-year-old woman who had a huge cystic lesion in her right hepatic lobe was transferred to our hospital for further examinations. Imaging studies revealed a simple liver cyst, and the cytological findings of intracystic fluid were negative. She was followed up periodically by computed tomography （CT） scans. Seven years later, she complained of a prominence and dull pain in her right thoraco-abdominal region. CT revealed an enlargement of the cystic lesion and infiltration into the intercostal subcutaneous tissue. We suspected the development of a malignancy inside the liver cyst such as cystadenocarcinoma, and she therefore underwent surgery. A tumor extirpation was performed, including the chest wall, from the 7th to the 10th rib, as well as a right hepatic Iobectomy. Pathologically, the lesion consisted of severe inflammatory change with epithelioid cell granuloma and bone destruction without any malignant neoplasm. No specific pathogens were evident based on further histological and molecular examinations. Therefore the lesion was diagnosed to be a destructive granuloma associated with a long-standing hepatic cyst. Since undergoing surgery, the patient has been doing well without any signs of recurrence.