IGFBP-1 is expressed specifically in ovarian clear cell adenocarcinoma.

AIMS: To investigate the specific expression of insulin-like growth factor binding protein-1 (IGFBP-1) in ovarian clear cell adenocarcinoma (CCA). METHODS AND RESULTS: Immunohistochemistry and in situ hybridization for IGFBP-1 were performed in normal endometrium, placenta, and 100 surgically resected cases of ovarian cancer including 31 CCAs and 69 non-CCAs. Immunohistochemistry for hepatocyte nuclear factor-1 (HNF-1ß) was also examined in all cases. Specific expression of IGFBP-1 was confirmed in secretory endometrium, decidua of placenta and Arias-Stella glands of miscarriage material. Among ovarian cancers, almost all cases of CCA showed expression of both IGFBP-1 protein and mRNA, but non-CCA hardly expressed IGFBP-1. There was a significant difference between CCA and non-CCA in the expression of IGFBP-1 protein and mRNA. No correlation was found between the rate of IGFBP-1 expression and pathological T and N factors of the tumour-node-metastasis (TNM) classification. All CCA cases except for one exhibited expression of HNF-1ß protein, whereas only 15.9% of non-CCAs did so. CONCLUSION: The expression of IGFBP-1 in CCA is more specific than that of HNF-1ß. IGFBP-1 shows expression by decidual endometrium and Arias-Stella glands, and CCA also exhibits characteristic expression. These results indicate that IGFBP-1 is a immunohistochemical marker for CCA.

Gastric T-cell lymphoma with cytotoxic phenotype.

Primary gastric lymphoma usually originates from B cells of mucosa-associated lymphoid tissue (MALT) infected with Helicobacter pylori. When T-cell lymphomas develop in the stomach, they usually occur in association with infection by human T-lymphotropic virus type 1 and gastric involvement of adult T-cell leukemia. Reported herein is a unique and informative case of gastric peripheral T-cell lymphoma with a cytotoxic phenotype that histologically mimicked, and had to be carefully distinguished from, MALT-type B-cell lymphoma. The patient, a 73-year-old woman, underwent a gastric endoscopy examination, and the histological findings suggested MALT-type gastric lymphoma. Analysis of the immunoglobulin heavy chain (IgH) gene and T cell receptor gamma (TCRgamma) gene revealed monoclonal rearrangement of the TCRgamma gene. The tumor cells exhibited mild atypia and immunoreactivity with anti-CD3, anti-CD8, anti-T-cell intracellular antigen-1, antigranzyme B and antiperforin antibodies, but not with anti-CD20, anti-CD10, and anti-CD79a antibodies. The case was finally diagnosed as gastric T-cell lymphoma with cytotoxic phenotype, and this was confirmed after surgical resection. In cases such as this, small biopsy specimens from the stomach should be examined carefully for low grade B-cell-type malignant lymphoma (MALT lymphoma), because sometimes the proliferating B cells can hide the truly malignant T cells, and rearrangement analysis is useful for diagnosing T-cell malignancy.