What is the role of adjuvant chemotherapy in stage I?
Most guidelines have recommended observation for T1ab, N0 NSCLC with negative margins. (Supplementary Table 1) There is no evidence of a clear survival benefit for post-operative adjuvant chemotherapy for stage IA disease. The role of adjuvant chemotherapy in stage IB NSCLC remains controversial. There appears to be no benefit in patients with stage IA disease but there may be benefit in those with tumours >4 cm.4, 5In a phase III study of patients with resected stage IB NSCLC randomized to carboplatin/paclitaxel or observation (CALGB 9633), survival was similar in both arms (HR 0.83; 95% CI, 0.64- 1.08; P = 0.12). Post-hoc exploratory analysis demonstrated a significant survival difference in favor of adjuvant chemotherapy for patients who had tumours 4 cm in size (HR 0.69; 95% CI, 0.48- 0.99; P = .043). In a retrospective analysis of an adjuvant study JBR.106, patients with tumours 4 cm or larger benefited from adjuvant chemotherapy (HR 0.66; 95% CI, 0.39- 1.14; P = 0.13).5However these analyses are post-hoc and caution should be exercised in interpreting their significance.
Recommendations on the Role of Adjuvant Chemotherapy in Stage I
After review of the guidelines and by consensus, the workgroup is in favour of adopting the NCCN guidelines.
Recommendations are as follows:
1.Observation is recommended for patients with T1ab, N0 tumours with negative surgical margins (Category 2A).
2.Patients with T2ab, N0 tumours with negative surgical margins are usually observed (Category 2A).
3.Chemotherapy is recommended for high risk features (include poorly differentiated tumours, vascular invasion, wedge resection, >4cm, visceral pleural involvement, and incomplete LN sampling) (Category 2A).