Inhaled Chemotherapy

Cytotoxic chemotherapy remains the cornerstone of treatment for patients diagnosed with advanced stage cancers and is an important component in the multi-disciplinary treatment of several early stage cancers. In the majority of patients with cancer, cytotoxic chemotherapy is administered intravenously and in some instances by oral administration. Systemic administration of cytotoxic chemotherapy is well known to cause adverse effects, which can be severe and debilitating. Regional therapy with cytotoxic agents has the potential to reduce the extent of systemic exposure to the drug and reduce the risk of systemic adverse effects. Regional chemotherapy has been successfully employed in the treatment of certain solid tumors such as hepatocellular carcinoma. However, regional chemotherapy has not been commonly utilized for treatment of lung tumors. Inhaled cytotoxic chemotherapy has the potential to become an effective regional therapy for both primary lung cancer and metastases to the lung from other primary tumors. Aerosol administration of chemotherapy could potentially avoid some of the adverse effects seen with systemic therapy. In addition, some chemotherapeutic agents when administered as an aerosol are absorbed directly into the arterial circulation and have therapeutic effects at extrapulmonary sites. Aerosol administration of several different chemotherapeutic agents is currently under evaluation either in the preclinical setting or in early phase human trials. Some of these studies have shown that inhaled chemotherapy is feasible and effective in treating lung tumors. In this chapter, we review the published studies and ongoing trials on inhaled chemotherapy to better understand the current status of this field of cancer treatment.