INACTIVATION OF RETINOBLASTOMA GENE IN MALIGNANT PARATHYROID GROWTHS - A CANDIDATE GENETIC TRIGGER

The molecular basis for parathyroid carcinoma remains undetermined. Pa rathyroid carcinoma potentially remains curable by early en bloc resec tion. This requires a reliable diagnostic tool as histological feature s alone are insufficient to distinguish parathyroid carcinoma from its benign counterpart, parathyroid adenoma. A variety of human cancers a rise from the inactivation of the retinoblastoma (RE) gene, a tumour-s uppressor gene on chromosome 13q14. We investigated the role of this g ene in parathyroid growths by using a mouse monoclonal antibody to det ect RE gene expression immunohistochemically. Two of the three parathy roid carcinomas in this study showed evidence of RE gene inactivation compared with one of 11 benign parathyroid entities. Three normal para thyroid glands stained showed strong evidence of RE gene expression in all three glands. The relationship between RE gene inactivation and p arathyroid malignancy, however, was not statistically significant.