ESTABLISHMENT OF AN EXPERIMENTAL INTRAPULMONARY TUMOR NODULE MODEL

Background. A pulmonary tumor model is necessary to study the biology and therapy of lung cancer. Methods to establish a solitary intrapulmo nary nodule are not well defined. Two methods for solitary intrapulmon ary tumor nodule development in the Fischer rat are described. Methods . Methylcholanthrene-induced sarcoma cell suspensions were introduced into lung parenchyma of Fischer rats via limited thoracotomy and lung puncture, or instilled into a distal airway after tracheal puncture an d catheterization, Intrapulmonary tumor location, implantation mortali ty, procedure length, and animal survival were recorded. Results. Sing le pulmonary nodules developed at the implanted position in 100% (n = 320) and 95% (62/65) of animals after direct injection into the pulmon ary parenchyma or via tracheal puncture and instillation. Operative mo rtality was 2% and 5% via lung or tracheal implantation, respectively. Less than 5 minutes was required for each implantation. Mean survival time was 24 +/- 2 and 26 +/- 6 days after lung or tracheal implantati on in animals allowed to survive until tumor-induced death. Conclusion s. These easily performed, reproducible methods of establishing solita ry intrapulmonary tumors are useful tools for lung cancer research. (C ) 1997 by The Society of Thoracic Surgeons.