Carney's Triad comprises a triad of neoplasms: gastric stromal tumor, 
extra-adrenal paraganglioma (usually functional), and pulmonary chondroma. At 
least two of these are needed for the presumptive diagnosis of the Triad. This 
report presents a patient who had resected a gastric tumor and nonfunctional 
extra-adrenal paraganglioma. The gastric tumor resembled a gastric 
leiomyosarcoma by light microscopy, but electron microscopy revealed it to be a 
gastric autonomic nerve (GAN) tumor. Based on this evidence it appears that both 
the gastric lesions and the paragangliomata of Carney's Triad are tumors of the 
autonomic nervous system. Thus, the Triad may be a disorder of the autonomic 
nervous system rather than a multiple endocrine neoplasia syndrome or multiple 
hamartoma syndrome.