Late histopathological findings in the thoracic irradiation: A preliminary study in the animal model

To investigate late histopathological alterations in rat lung cells following single-dose of irradiation.
Methods and materials: The thoracic cage of entire lung of Wistar rats was exposed to 17 Gy 60Co gamma rays.
The animals were sacrificed at 32 weeks after irradiation. The lungs were dissected and blinded histopathological
evaluation was performed. Results: When the lungs were removed at 32 weeks after whole thoracic irradiation,
histopathologically inflammation and mononuclear infiltrate in the interstitium, Intraalveolar hemorrhages,
dilatation in the alveolar space with alterations of the alveolar wall, congestion of the dilated vessels, foam and dust
cells and superimposed collagen were noted in all animals. Conclusion: At the end of the histological examination,
it was seen that all of the animals had severe superimposed collagen and a large fibrous area. We conclude that, in
the rat lung model with single dose of 17 Gy, the most interesting finding in this study was in the expression of late
fibrosis.