Neoplastic angioendotheliosis: demonstration of immunoglobulin gene rearrangements by the Southern blot hybridization technique.

Using the Southern blot hybridization technique, two cases of 'neoplastic angioendotheliosis' (NAE) were examined for immunoglobulin gene rearrangements. For DNA analysis, frozen kidney (Case 1) and lung (Case 2) tissue, in which intravascular neoplastic cells were abundant, were used. In each case rearrangements were observed in both heavy and light chain genes. On examination of the heavy chain gene, the JH DNA probe detected one rearranged band in Case 1 and two in Case 2 after EcoRI digestion. On examination of the light chain genes, the C kappa DNA probe revealed one rearranged band in Case 1 and two in Case 2 after BamHI digestion, while the C lambda 2 DNA probe revealed only germline configurations after EcoRI digestion in each case. Thus, B-lymphocytic differentiation at the gene level was demonstrated in neoplastic cells in both cases. Since no more than two rearrangements were detected in each immunoglobulin gene, the intravascular neoplastic cells were considered to be monoclonal in nature.