Current development of adjuvant treatment of non-small-cell lung cancer

Although radical surgery remains the mainstay therapeutic modality for early-stage non-small-cell lung cancer (NSCLC), long-term survival of patients with completely resected NSCLC tumors remains suboptimal. Globally, the 5-year survival rate of patients who undergo complete surgical resection is in the range of 40%-50%. The majority of postsurgical relapses are represented by distant metastases, with the risk of a local recurrence being < 10%. Postoperative treatments, including chemotherapy, radiation therapy, or both, have been widely evaluated during recent decades. After almost 2 decades of disappointing results, the positive outcomes of 3 randomized studies have recently generated new hopes for a significant impact on survival by adjuvant chemotherapy. The 2 largest randomized studies of adjuvant chemotherapy in all stages (I-IIIA) of completely resected NSCLC that were adequately powered to detect small differences in survival yielded partially conflicting results but indicated that, if any benefit from adjuvant chemotherapy exists, it is approximately 5% at 5 years, as previously anticipated by a metaanalysis. More recently, 2 other randomized studies in selected subgroups of patients (one selectively performed in stage IB disease, the other in stage IB/II disease) indicate an unexpected significant benefit of approximately 15% at 5 years. Potential confounding factors may have contributed to such a significant benefit. A feature common to all these trials is the suboptimal therapeutic compliance to adjuvant chemotherapy, suggesting the need for careful selection of patients to be considered for adjuvant treatment. Genomic- and proteomic-driven chemotherapy as well as molecularly targeted therapies may represent additional areas of near-future clinical investigations.