Establishment of an orthotopic model of lung cancer by transthoracic lung puncture using tumor fragments

BACKGROUND: Orthotopic models of lung cancer have been widely utilized, and the purpose of this study was to demonstrate the viability of our proposed modified modeling approach. METHODS: A total of 50 female BALB/c mice were implanted with 1×1×1 mm fragments of a tumor sample into the left lung lobe. After 2 months of observation, the mice were humanely euthanized through CO(2) inhalation. The macroscopic specimens were photographed, and the most representative neoplastic lesions were collected for histological analysis. Small-animal positron emission tomography/computed tomography (PET/CT) scans were conducted on 6 randomly selected mice. RESULTS: Local tumor formation, ipsilateral thoracic tissue infiltration, the contralateral chest wall, right lung metastases, and distant kidney metastases were observed in these models. Overall, the tumor development and metastasis rates were 60.86% (28/46) and 57.14% (16/28), respectively. The 3 mice that had a small-animal PET/CT scan developed a local tumor, but no distant metastases were observed. CONCLUSIONS: This modified method was deemed reliable, reproducible, minimally invasive, straightforward, and comprehensible; it might serve as the foundation for developing patient-derived orthotopic xenografts of lung cancer.