PLURIPOTENT TUMOR-CELLS IN BENIGN PITUITARY-ADENOMAS ASSOCIATED WITH MULTIPLE ENDOCRINE NEOPLASIA TYPE-1

Analysis of human tumor cells in vitro enhances the study of numerous neoplastic conditions. However, it has been difficult to establish lon g-term cultures of adenoma cells, especially those of neuroendocrine o rigin, because the endocrine cells survive only briefly in culture, an d fibroblasts overgrow the culture dish in 1 or 2 weeks. We describe c ells isolated from pituitary adenomas in two patients with multiple en docrine neoplasia type 1 in which cells with a mesenchymal phenotype e volved from pituitary tumor cells. It appears that these poorly differ entiated cells arose from multipotent adenoma cells. This represents a path of cell differentiation not observed previously in humans and ma y help explain the diverse nature of the benign tumors in multiple end ocrine neoplasia type 1.