Induction of neuroendocrine lung tumors in hamsters

We examined whether induction of neuroendocrine cell tumors in hamster lungs, following treatment with hyperoxia and diethylnitrosamine (DEN) was dependent upon hyperoxia or upon nitrosamine exposure. In hamsters exposed to 70% oxygen for 13 weeks and given a total of 1.6 uCi of Polonium-210 intratracheally, 5 out of 10 developed multiple small cell cancers with a malignant growth pattern, invading blood vessels and bronchi. In hamsters kept in an atmosphere of 12% oxygen and injected twice a week, for 16 weeks, with 20 mg/kg of DEN, 3 out of 10 had tumors resembling carcinoids. We conclude that neuroendocrine cell hyperplasia, caused by hyperoxia or by hypoxia and exposure to a chemical carcinogen specific for the lung or to a physical carcinogen deposited in the lung is instrumental in the development of neuroendocrine lung tumors