Intermediate filaments as differentiation markers of exocrine pancreas. II. Expression of cytokeratins of complex and stratified epithelia in normal pancreas and in pancreas cancer

Cytokeratin (CK) expression in tumors generally reflects the CK pattern of the corresponding normal epithelium. Pancreas cancers express CK of simple epithelia 7, 8, 18 and 19, as normal ductal cells. To analyze whether CK of complex or stratified epithelia are abnormally expressed in pancreas cancers, we have used polypeptide-specific mouse monoclonal antibodies (MAbs) detecting CK 5, CK 10, CK 13, CK 14 and CK 17, and an antibody detecting CK 13, CK 15 and CK 16. The streptavidin-peroxidase technique was applied on sections of fresh-frozen specimens of normal pancreas and of pancreas cancer. None of these polypeptides were expressed by normal acinar and centro-acinar cells. CK 5, CK 14 and CK 17 were expressed by less than 5% of cells in normal ducts, whereas CK 10, CK 13, CK 15 and CK 16 were not expressed at all. In tumors, CK 14, CK 15/16 and CK 17 were detected in the majority of cases studied; CK 5, CK 10 and CK 13 were present in a sub-population of pancreas cancers. CK of complex/stratified epithelia were detected in areas of glandular differentiation, but expression was more intense in areas of squamous differentiation. In pancreatitis adjacent to cancer, CK of complex/stratified epithelia were weakly detected or undetectable. These results suggest that up-regulation of these CK takes place in pancreas cancer. The CK phenotype may be of help in the differential diagnosis of this tumor.

Renal infection due to Absidia corymbifera in an AIDS patient

A case of renal zygomycosis due to Absidia corymbifera in an heroin addict suffering from AIDS (phase IV C2) is described. Diagnosis was by histopathology after nephrectomy, but A. corymbifera was isolated several times from urine and from the exudate from a fistula in the surgical wound. After amphotericin B treatment (1.5 g overall dose) clinical cure and negative cultures were obtained. No relapses were observed until death 1 year later from Pneumocystis carinii pneumonia.

[Undifferentiated small cell carcinoma of the urinary bladder. Clinicopathologic and immunohistochemical study]

Small cell carcinoma of the bladder ("oat cell") is a very uncommon tumor. Its sudden onset, rapid progression to an often fatal outcome and early metastatic spread are the main clinical features of this tumor. Immunohistochemical staining for neuroendocrine markers is positive in a large number of cases. A case of small cell carcinoma of the bladder is described. The clinical course of the patient, as well as the histopathological and immunohistochemical findings are presented.

[Acquired immunodeficiency syndrome and T-cell non-Hodgkin's lymphoma]

The clinical observation of a 40 years old male presenting acquired immune deficiency syndrome and T-cell non Hodgkin's lymphoma is presented. The patient was treated with COMET-A regimen (cyclophosphamide, vincristine, methotrexate, etoposide and cytarabine) and a complete remission was obtained.

[Solitary contralateral, asynchronous adrenal metastasis of renal adenocarcinoma. Review of the literature]

A case of solitary, contralateral, asynchronous adrenal metastasis that appeared 5 years following nephrectomy is described herein. To our knowledge, ours is the fifth case reported in the world literature.

Primary cutaneous lymphoplasmacytic lymphoma

A case of a primary cutaneous lymphoplasmacytic lymphoma synthesizing IgG lambda chains is reported. Immunohistochemical studies were done with the use of antihuman immunoglobulin antisera and monoclonal antibodies against T cell antigens. These studies reveal an unusual pattern of immunoglobulin production (IgG lambda chains) and an important population of accessory cells (T cells and Langerhans cells).