Faculty Bibliography

Most patients with lung cancer subjected to surgical resection are likely to have residual tumor burdens which lead to clinical relapse and death. Unfortunately, none of the systemic therapies for squamous cell, large cell and adenocarcinoma of the lung have demonstrated curative potential either in the advanced disease or in the surgical adjuvant setting. Interest in clinical trials of adjuvant therapy in lung cancer have been rekindled by three factors: 1) reports indicating the value of immunotherapy, 2) preliminary encouraging experience with new chemotherapy programs, and 3) methodologies including stage- and cell type-specific clinical trials leading to better interpretation of results. These concepts have stimulated new treatment protocol studies within the NCI-sponsored Lung Cancer Study Group, and clinical cooperative groups.

New concepts and treatments currently available for adjuvant studies are illustrated by a review of ongoing studies sponsored by the National Cancer Institute. More thorough information is needed on immunotherapeutic agents to allow more rationale in the use of these agents. Solid bases to properly select drugs or drug combinations for adjuvant purposes are being established. However, dose-schedule and duration of treatment are still to be defined. Strategies directed at prolonging the benefit of surgical adjuvant chemotherapy remain to be planned. Progress continuously achieved with immunotherapy and chemotherapy should rapidly broaden the spectrum of tumour types to be included in adjuvant studies.

A variety of adjuvant trials performed in the United States for osteogenic sarcoma, breast, lung, and colon cancer have achieved encouraging results and are briefly summarized. Trials in osteogenic sarcoma are reporting 2-year disease-free survival rates of 50%. However, they have only been evaluated against historical controls and there is some evidence that other factors might have greatly improved the disease-free survival in the absence of adjuvant therapy. The NSABP breast cancer trial only shows significant improvement for women under 50 years of age with 1 to 3 positive axillary nodes. A very promising trial using intrapleural BCG immunotherapy for squamous cell lung cancer is described. Also, two trials of 5-fluorouracil for colo-rectal cancer, both showing trends suggesting slight improvement among treated patients, are presented. Proper care in the design of adjuvant trials with sufficient attention paid to prognostic variables is urged.