Abstract
BACKGROUND: Malignant pleural effusion resulting mainly from pleural metastases of lung adenocarcinoma has clinical relevance, being a sign of poor prognosis and low life expectancy. Experimental models can mimic the human condition, contributing to advances in current understanding of the mechanisms patients' pleural fluid accumulation and possible therapeutic strategies. The objective of this study is to evaluate the role of different concentrations of Lewis lung carcinoma cells (LLC cells) at the time of induction of experimental MPE and the main effects on survival of animals. METHODS: C57BL/6 mice received intrapleural injection of 0.1, 0.5 or 1.5 × 10(5) LLC cells and survival curve, biochemical and pathological analyses of pleural fluid and tissue were analyzed. RESULTS: Evaluation of weight loss, mobility and survival showed that animals that received 0.5 × 10(5) cells maintained more stable condition up to day 14 and a gain of 6 days survival over mice that received the highest concentration. CONCLUSION: This study may allow a better understanding the mechanisms involved in the development of malignant pleural effusion and it may be promising in evaluating therapy to avoid recurrence, as the best time to indicate pleurodesis or target therapies.