Research defines timeframes, factors to deem early stage lung cancer cured

In patients with non-small cell lung cancer (NSCLC), five-year disease-free survival is currently the benchmark of cure. However, there are two issues that remain with the follow-up standards: (1) When can cure be declared with confidence and (2) for how long should follow-up examination be continued?

In order to define a strategy for long-term follow-up for early stage lung cancer patients, research published in the August edition of the Journal of Thoracic Oncology (JTO) quantified the risk of late recurrence in patients with stage IA NSCLC who remained recurrence-free for more than five years after complete tumor resection. Overall, the findings indicate that in patients with stage IA NSCLC without vascular invasion (cancer cells within blood vessels), five years may be sufficient to declare that the patients are cured. In contrast, patients with stage IA NSCLC with vascular invasion need follow-up until at least nine years after resection.

In this study, the research team identified a total of 519 patients with stage IA NSCLC who underwent complete resection between August 1992 and December 2002. Recurrence-free probability was measured from the benchmark of five years after primary tumor resection to the date of first recurrence or last follow-up. Of the 519 patients, 434 remained recurrence-free for the first five years. Among these, only 21 (4.8 percent) developed late recurrence more than five years after resection.

The researchers identified one independent significant predictor of late recurrence in stage IA five-year recurrence-free survivors: the presence of vascular invasion. The five-year recurrence-free probability from the benchmark was 84 percent for patients with vascular invasion and 95 percent for patients without vascular invasion.

Summarizing the findings, lead investigator, Ryo Maeda, MD, explains that "If they are recurrence-free, patients without vascular invasion may be declared cured at five years after resection. On the other hand, patients with stage IA NSCLC with vascular invasion, five years without recurrence is not sufficient to conclude that NSCLC is cured."