Differences in patterns of recurrence in early-stage versus locally advanced non-small cell lung cancer

The benefits of screening for non-small cell lung cancer (NSCLC) have been established for high-risk individuals, and recent guidelines advocate continued surveillance after curative therapy. Yet the optimal posttreatment surveillance strategy remains to be determined. We compared patterns of recurrence and modes of detection in surgically treated patients with pathologic early-stage and locally advanced NSCLC.

Consecutive patients who had undergone resection for stage I-IIIA NSCLC from 2004 to 2009 were identified from a prospectively maintained institutional database. All patients received interval chest computed tomography (CT) scans every 6 to 12 months after treatment.

In total, 1,640 patients were identified: 181 of 346 patients with stage IIIA NSCLC (52%) and 257 of 1,294 patients with stage I-II NSCLC (20%) experienced recurrences. Surveillance CT detected asymptomatic recurrences in 157 stage I-II patients (61%) and 89 stage IIIA patients (49%) (p=0.045). Symptoms led to detection of recurrences more often in stage IIIA patients (73, 40%) than in stage I-II patients (81, 32%). Distant recurrences were more common in stage IIIA patients than in stage I-II patients (153, 85%, vs 190, 74%; p=0.01). In stage IIIA patients, the risk of recurrence was highest during the first 2 years after operation, but it remained substantial into year 4.

Stage IIIA patients had fewer recurrences detected by surveillance CT, a higher rate of symptomatic presentation, a markedly higher risk of recurrence, and a higher propensity for distant recurrence. Surveillance strategies may need to account for stage-specific differences.