Tumors, Malignant: Chemotherapeutic Agents

Lung cancer is a common and deadly neoplasm, responsible for the majority of cancer deaths worldwide. Well-controlled clinical trials demonstrate that chemotherapy treatment offers a survival advantage in all stages of all types of lung cancer, including those which fit under the larger heading 'non-small cell lung cancer' (adenocarcinoma of the lung, squamous cell carcinoma, and large cell carcinoma) as well as small cell lung cancer. The benefits vary considerably depending upon the stage and performance status of the patient. In non-small cell lung cancer, which accounts for 85% of lung cancers, adjuvant chemotherapy has demonstrated a marked benefit, increasing cure rates by 10-15%. In locally advanced disease, chemotherapy has also demonstrated unequivocal benefit in improving survival when combined with either radiotherapy or surgery. In metastatic disease, benefits have been clearly demonstrated in terms of quality and length of life for both initial treatment as well as salvage therapies. However, the survival of these patients is usually brief and much work needs to be done in terms of both, developing new agents and better utilization of available drugs. Small cell lung cancer has historically been considered the more responsive of the lung cancer types, with a majority of patients demonstrating disease shrinkage. In limited disease the combination of chemotherapy with radiotherapy can result in cure in approximately 25% of patients. In extensive disease, the majority of patients will experience shrinkage of disease, frequently with substantial symptomatic benefit. Unfortunately, this response is frequently shortlived with rapid regrowth of disease. The progress of the last decade has removed a previously nihilistic attitude towards the drug treatment of lung cancer and led to a renaissance in lung cancer research. Numerous new agents and approaches are being explored including modifications of existing families of agents as well as development of new agents targeted on molecular pathways felt to be crucial to the survival and proliferation of this malignancy.