[Neurogenic stomach neoplasms induced by nitrosomethylures in Syrian hamsters].

In the experiment with inoculation of N-nitroso-N-methylurea (a maximum total dose of 7.5 mg) to Syrian hamsters, tumors developed in 20 out of 25 animals surviving the time of the occurrence of the first tumor (31 weeks). Out of 35 tumors 17 developed at the site of inoculation: in the left cheek pouch (of them 12 embryonal rhabdomyoblastomas), 11 in the stomach (of them 6 neurogenic), and 7 in other organs (skin, liver, adrenals, hemopoietic system). The paper describes the histological pattern of 6 neurogenic tumors of the stomach in which all the elements of the nervous system have been found: ganglionic cells, neuroglia, and nerve stems. On the basis of some signs the authors classify these tumors as malignant.