n-n-diamylnitrosamine and Lung-Neoplasms

Through 25 weekly subcutaneous injections of dipentylnitrosamine (DPNA), metastasizing lung carcinomas were induced in 56 Hann: Wistar rats. Among them nine animals had intracranial metastases. Four metastases were localized in the pituitary, three in the choroid plexus of the IIIrd ventricle, one in the choroid plexus of the IVth ventricle, and one in the brain-stem. Thus, the preferential sites of intracranial metastasis were the choroid plexus of the ventricles and the pituitary. No metastatic spread was found in the cerebral hemisphere. Five of the metastatic tumours resembled the primary pulmonary adenocarcinoma. In the other four, the primary was an adenosquamous carcinoma but only adenocarcinomatous components were present in the metastasis.

Topics: Adenocarcinoma; Animals; Brain Neoplasms; Carcinoma, Squamous Cell; Cerebral Ventricle Neoplasms; Female; Lung Neoplasms; Male; Nitrosamines; Pituitary Neoplasms; Rats; Rats, Wistar

In Hann:Wistar rats, 25 weekly subcutaneous injections of dipentylnitrosamine (DPNA) at doses of 0, 62.5, 125 and 250 mg/kg body weight induced lung carcinomas which metastasized partly. The incidence of the primaries was 2.5, 20.0, 77.5 and 100% in the males and 0, 0, 12.5 and 57.5% in the females, respectively. The frequency of metastases was 0, 12.5, 38.7 and 72.5% in the males and 0, 0, 40.0 and 52.2% in the females, respectively. The most common metastatic sites in males and females together were: lung-associated lymph nodes (82.1%), adrenal gland (53.6%), kidney (39.3%), pancreas (32.1%), bones (16.1%), heart (12.5%), mesentery (12.5%) and CNS (8.9%). In the females, metastases were also detected in the uterus (21.4%) and ovary (42.9%). The results indicate that: (1) through subcutaneous injections of DPNA metastasizing lung carcinomas can be induced with high incidence, and (2) the metastatic pattern is very similar to human cases. Thus, this model could be useful for the study of metastasizing lung carcinomas in experimental animals.

Topics: Adenocarcinoma; Animals; Carcinogens; Female; Lung Neoplasms; Lymphatic Metastasis; Male; Neoplasm Metastasis; Nitrosamines; Rats; Rats, Inbred Strains; Sex Factors