Consecutive CT-guided core needle tissue biopsy of lung lesions in the same dog at different phases of radiation-induced lung injury.

This project aimed to set up a Beagle dog model of radiation-induced lung injury in order to supply fresh lung tissue samples in the different injury phases for gene and protein research. Three dogs received 18 Gy X-ray irradiation in one fraction, another three dogs received 8 Gy in each of three fractions at weekly intervals, and one control dog was not irradiated. Acute pneumonitis was observed during the first 3 months after radiation, and chronic lung fibrosis was found during the next 4-12 months in all the dogs exposed to radiation. CT-guided core needle lung lesion biopsies were extracted from each dog five times over the course of 1 year. The dogs remained healthy after each biopsy, and 50-100 mg fresh lung lesion tissues were collected in each operation. The incidence of pneumothorax and hemoptysis was 20% and 2.8%, respectively, in the 35 tissue biopsies. A successful and stable radiation-induced lung injury dog model was established. Lung lesion tissue samples from dogs in acute stage, recovery stage and fibrosis stage were found to be sufficient to support cytology, genomics and proteomics research. This model safely supplied fresh tissue samples that would allow future researchers to more easily explore and develop treatments for radiation-induced lung injury.