Surgical adjuvant therapy for lung cancer.

Many patients with lung cancer have disease disseminated beyond the thorax at the time of presentation. In patients with resectable disease, the first site of recurrence following surgery is frequently outside of the thorax. Therefore, the major problem in lung cancer is control of distant metastatic disease rather than failure to control local disease. For these reasons, adjuvant therapy has been directed primarily toward the microscopic systemic disease. Immunotherapy has shown some promise as a systemic agent in lung cancer, but it is clear from the early trials that the effect of immunotherapy is marginal. Newer types of immunotherapy are being developed, and at the present time, intralesional BCG immunotherapy holds considerable promise. However, the ultimate success of immunotherapy will reply on the development of better immunotherapeutic agents and a better knowledge of the immunologic relationship between the host and the tumor. Studies evaluating chemotherapy as a systemic adjuvant to surgery have not been promising in the past. However, new combination chemotherapeutic regimens that have a response rate of 40 per cent in advanced disease and that have acceptable toxicity offer considerable promise in the area of adjuvant therapy. Certainly adjuvant chemotherapy has been successful in sarcomas, germ cell tumors of the testes, Wilms' tumors, and breast cancer, as well as other solid tumors, and its reasonable to anticipate that effective combination chemotherapy will be developed that will be useful as a surgical adjuvant in lung cancer. Several trials are currently in progress evaluating preoperative chemotherapy in advanced resectable disease and also postoperative adjuvant therapy following total resection. These studies are now in progress and the preliminary results are encouraging, but the definitive statement cannot yet be made.