Splenic marginal zone lymphomas appear to originate from different B cell types.

Splenic marginal zone lymphomas (SMZLs) have been proposed to originate from postgerminal center memory B cells that usually have mutated immunoglobulin heavy-chain variable (VH) genes. However, the majority of SMZLs are thought to express both IgD and IgM, which is more typical of naïve B cells that have unmutated VH genes. To better define the SMZL cell of origin and pathogenesis, we studied the histological and immunophenotypic features of eight cases and also sequenced their rearranged VH genes.

p53 immunohistochemistry for distinguishing reactive mesothelium from low grade ovarian carcinoma.

Objective: To determine the utility of immunohistochemical staining for p53 in cell block material for distinguishing reactive mesothelium from borderline or low grade ovarian carcinoma.

Study Design: Paraffin-embedded cell blocks from paracentesis and pelvic wash fluid of 44 cases of ovarian carcinoma and 20 cases containing only reactive mesothelium were immunostained for p53 using monoclonal antibody DO-7. Tumor grades ranged from borderline to high grade and were serous papillary (33), clear cell (3), mucinous (2), endometrioid (2), mixed serous papillary/clear cell (3) and undifferentiated (1).

Expression of p21WAF1/CIP1 in soft tissue sarcomas: a comparative immunohistochemical study with p53 and Ki-67.

The p53 gene controls the cell cycle by transactivating p21WAF1/CIP1, a cyclin dependent kinase (cdk) inhibitor. By inhibiting cdks, p21WAF1/CIP1 regulates the cell cycle by blocking the G1 to S phase transition. In this study, we analyzed the immunohistochemical expression of p21WAF1/CIP1 in 66 soft tissue sarcomas and its relationship to p53 and the cell cycle proliferation antigen Ki-67.

Tumor-associated glycoprotein (TAG-72) in endometriotic implants.

Tumor-associated glycoprotein (TAG-72) is an antigen detected by the monoclonal antibody B72.3 that is expressed by a wide variety of human malignancies and in normal secretory endometrium. Serum TAG-72 may be elevated in women with endometriosis, but the distribution of TAG-72 in this disorder has not been well studied.