We have investigated the occurrence of type-1 inhibitor of plasminogen activators (PAI-1) in human breast tumors. PAI-1 levels, measured by enzyme-linked immunosorbent assay, were significantly higher in malignant breast carcinomas (n = 178) than in benign breast tumors (n = 25). The levels of PAI-1 were found to be correlated with those of urokinase-type plasminogen activator (u-PA). The presence of PAI-1 in tumor extracts was also demonstrated by immunoblotting analysis. Immunohistochemical investigations by the use of monoclonal and polyclonal antibodies showed that PAI-1 was mostly localized in the tumor islands, associated with the tumor cells; in addition, it was present in vessel walls and in normal duct epithelia, but absent from the stroma. Analysis of RNA extracted from tumors by polymerase chain reaction revealed the presence of PAI-1 mRNA. We conclude that PAI-1 is present in human breast carcinoma cells, and that it is--at least partially-- produced locally, either by the cancer cells or by other cells in the tumors. We have previously demonstrated that a high level of u-PA in human breast carcinomas is associated with poor prognosis. These results, combined with our present findings, present 2 possibilities: either the cancer cells need PAI-1 in order to utilize the u-PA-mediated pathway of plasminogen activation for invasion and metastasis; or PAI-1 represents a defense mechanism against tumor invasion.

Amyloid masses of the gastrointestinal tract are very rare. A previously undescribed finding of multiple gastric polyps due to systemic amyloidosis is outlined in a patient with familial amyloid polyneuropathy. The relevant literature pertaining to gastric amyloidosis and mucosal masses is reviewed. Amyloidosis should be included in the differential diagnosis of target lesions in the stomach.

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laparoscopic liver resection. Final results from the Oslo-CoMet RCT comparing open and laparoscopic liver resection will be presented at IHPBA2016.