The Emergence of a Unique Population in Non-Small Cell Lung Cancer: Systemic or Loco-Regional Relapse Following Postoperative Adjuvant Platinum-Based Chemotherapy

Surgical resection remains the foundation of curative therapy in early stage non-small cell lung cancer (NSCLC). Recent evidence from several randomized trials has shown that adjuvant chemotherapy regimens of platinum-based agents plus third-generation cytotoxic agents improve survival rates in this population of patients. Despite the use of adjuvant chemotherapy, many patients will suffer a relapse, typically systemic, and be candidates for subsequent therapies. This represents a new population of patients with NSCLC. To date, there are no published trials that evaluate prognostic factors or therapeutic outcomes in these patients. Although therapeutic paradigms have been established in patients who present with de novo metastatic NSCLC, it is not clear whether these paradigms are successful for patients who relapse following platinum-based adjuvant chemotherapy. The influence of time from the previous adjuvant exposure is likely to be as important as it seems to be in other solid tumors. However, dedicated clinical research has not yet established this paradigm in NSCLC and the influence this should have on the choice of subsequent therapy is unknown. The nature of the prior adjuvant exposure may also play a role in the choice of subsequent therapy. This has implications for the design of future trials in advanced NSCLC as these patients may or may not have the same natural history as the de novo metastatic NSCLC patient. Future clinical trials are required to address these issues as well as the biologic heterogeneity that likely exists between patients who are seemingly cured by surgery, relapse early (<1 year), or at later times following adjuvant therapy.