Long-term effects of pulmonary damage in mice on lung weight, compliance, hydroxyproline content and formation of metastases

The development of 'metastatic' colonies of fibrosarcoma in the lungs of mice after IV injection of a single-cell suspension of tumour cells varied with time after irradiation or administration of bleomycin. Most notably, there was a late radiation-induced enhancement of colony-forming efficiency that coincided with an increase in lung weight and hydroxyproline content and a decrease in compliance. There was no radiation-induced enhancement of 'spontaneous' metastases from a mammary carcinoma implanted in the thighs of the animals. The sequence of events after administration of bleomycin was similar to that after irradiation, but the duration of the treatment was different and the temporal relationship between enhanced colony-forming efficiency and changes in lung weight and hydroxyproline content was not as clear cut.