Primary extranodal non-Hodgkin's lymphoma of the extrahepatic biliary tract.

A case of extranodal non-Hodgkin's diffuse, mixed small and large cell lymphoma of the extrahepatic biliary tract with jaundice as the initial manifestation is reported in this paper. Obstructive jaundice is very rarely an early symptom in lymphoma. The pathogenesis of jaundice in this case was infiltration of the extrahepatic bile duct by lymphoma cells and fibrosis.

Primary lymphoma arising in skeletal muscle.

A case of lymphoma arising primarily from the biceps muscle is reported. While this is an exceedingly rare event, lymphoma may also invade or metastasize to muscle, and should be considered in the differential diagnosis of tumours arising from skeletal muscle. Proper evaluation of a muscle mass includes biopsy with electron microscopy and immunohistochemical studies if the cell type of the tumour is uncertain. Treatment of a muscle mass based on the histologic diagnosis of undifferentiated neoplasm is unacceptable since it may lead to unnecessary radical surgery, while curative nonsurgical therapy is available.

Extraorbital sebaceous carcinoma.

Although sebaceous carcinoma constitutes 1% to 5.5% of all malignant neoplasms of the eyelid, less than 100 cases arising in extraorbital sites have been reported. We treated two cases of extraorbital sebaceous carcinoma arising in anatomic regions never previously reported, to our knowledge. These tumors occur generally in older patients and affect both sexes equally. No clinical features are characteristic of the tumor, but larger skin lesions should be approached with suspicion. Appropriate histopathologic identification is particularly important in the differential diagnosis. Radical surgery is the only effective treatment for this rare tumor, which can recur locally or produce lymph node and even distant metastases.

Mesenchymal chondrosarcoma of the kidney.

A case of mesenchymal chondrosarcoma of the kidney, with osseous metastases, is presented in this article, and the clinical, radiologic, and histopathologic features of this uncommon neoplasm are discussed. The addition of this case to those previously reported in the literature brings the total number of reported cases of mesenchymal chondrosarcoma of extraskeletal origin to 42. None of the previously reported cases originated from the kidney. The metastatic pattern of this case illustrates the propensity of mesenchymal chondrosarcoma to metastatize to unusual locations.

Hepatic prolyl hydroxylase and collagen synthesis in patients with alcoholic liver disease.

Hepatic prolyl hydroxylase activity and collagen synthesis were measured in patients with alcoholic liver disease to determine the feasibility of using the enzyme prolyl hydroxylase as a marker of hepatic fibrogenesis. Alcoholic patients with liver histopathology consistent with normal, steatosis, alcoholic hepatitis, early cirrhosis, or advanced cirrhosis were analysed for liver prolyl hydroxylase activity and in vitro collagen synthesis. Prolyl hydroxylase activity and the rate of in vitro collagen synthesis were correlated when these parameters were measured in samples of the same liver biopsy. Mean prolyl hydroxylase activity was significantly raised in all groups of alcoholic patients with alcoholic liver disease, except those with steatosis, when compared with alcoholic patients with normal morphology. Alcoholic patients with early cirrhosis had enzyme activity (mean +/- SE: 1.367 +/-0.162 mU/mg protein) significantly raised over all other groups. Mean enzyme activity was less raised (0.985 +/- 0.097 mU/mg protein) in patients with advanced cirrhosis. The percentage of collagen synthesis in patients with early or advanced cirrhosis was also raised compared with alcoholic patients with normal morphology. Prolyl hydroxylase activity and the rate of collagen synthesis are significantly correlated (r=0.62). These findings suggest that hepatic prolyl hydroxylase activity is a useful indicator of hepatic fibrogenesis and its measurement on available liver biopsy tissue should be a potent diagnostic tool reflecting active fibrogenesis and predicting progression of alcoholic liverdisease.