Metastatic ganglioneuroblastoma.Ultrastructural, histochemical, and virological studies in a case

The ultrastructure of lymph node and bone marrow tissue invaded by metastatic ganglioneuroblastoma was studied. Numerous unmyelinated axon-like cytoplasmic processes were seen among the tumor cells. These processes contained dense-cored, membrane-bound structures measuring from 70 to 110 mμ. in diameter. It has been suggested that such structures might represent catecholamine granules13, 15 but other possibilities such as oncogenic viruses should be considered. Inoculation into cell cultures, hemagglutination, and complement fixation studies failed to reveal any evidence for viral activity in the tumor tissue. Lymph node tumor cells exposed to paraformaldehyde vapor developed an intense green fluorescence. Lymph node sections stained by the ferroferricyanide and the tetrazolium reduction techniques gave a positive reaction in the tumor cells. It was felt that catecholamines, very probably norepinephrine, were present in the tumor cells and that the dense-cored, membrane-bound granules could represent storage granules. Their definite nature, however, could not be established with these studies.