Optimal adjuvant therapy for non-small cell lung cancer--how to handle stage I disease.

The standard of care for resected stage II-IIIA non-small cell lung cancer (NSCLC) now includes adjuvant chemotherapy based on the results of three phase III studies using cisplatin-based regimens--the International Adjuvant Lung Trial, the National Cancer Institute of Canada JBR.10 trial, and the Adjuvant Navelbine International Trialist Association trial. The role of adjuvant chemotherapy for stage I disease remains controversial. A recent meta-analysis (the Lung Adjuvant Cisplatin Evaluation) showed potential harm with the addition of adjuvant cisplatin for stage IA disease and no survival benefit for this modality in stage IB disease. Updated results from the Cancer and Leukemia Group B 9633 trial, the only trial to focus exclusively on stage IB patients, no longer show a statistically significant survival benefit from adjuvant chemotherapy in this population, except for the subgroup of patients with larger tumors. It may be that trials have been underpowered to detect a small benefit for patients with stage IB disease, or there may really not be benefit to adding adjuvant therapy for this stage of disease. Additional markers, such as tumor size or the presence or absence of certain tumor proteins like ERCC1, may help to determine which patients with resected stage I NSCLC may benefit from adjuvant chemotherapy. Strategies such as inhibition of angiogenesis pathways and the epidermal growth factor receptor are under exploration.