Inhalation therapy remains a suitable approach to treat lung diseases including cancer. This approach has been used to deliver various therapies including chemotherapy. The rationale for using the inhalation route vs. the systemic route has been the fewer side effects encountered when drugs are administered via inhalation. Furthermore, this approach overcomes one of the major limitations of systemic chemotherapy that results from inability of the drug to reach high concentrations in the lungs. Local delivery overcomes this limitation and spares exposure of vital organs to the drug, resulting in a more effective delivery system.Pulmonary metastasis of osteosarcoma (OS) remains a major cause of death and is very difficult to treat. Using various OS mouse models, we demonstrated that aerosol chemotherapy causes regression of pulmonary metastases and improves survival of mice with OS. In these studies, we used gemcitabine, a nucleoside analog that is effective against various solid tumors. An initial phase I study done in Europe in patients with primary lung cancer demonstrated aerosol gemcitabine therapy to be feasible and safe. In this chapter, we describe different chemotherapeutic agents delivered by inhalation to treat lung diseases with an emphasis on an ongoing study of aerosolized gemcitabine for patients with solid tumors and lung metastases developed at the MD Anderson Cancer Center that uses a convenient approach to track patient lung health with the ultimate goal of implementing this therapy at home.
Keywords: Aerosol; Gemcitabine; Inhalation therapy; Lung metastases; Osteosarcoma.