Prognostic significance of CT-determined emphysema in patients with small cell lung cancer.

BACKGROUND

Although emphysema and small cell lung cancer (SCLC) are prevalent in smokers, no previous study has investigated the prognostic impact of computed tomography (CT)-determined emphysema in SCLC. This study was undertaken to analyze the prognostic value of emphysema scores as determined by baseline CT scans in patients with SCLC.

METHODS

The data of 149 consecutive patients with SCLC were analyzed. Emphysema severity was semi-quantitatively scored on baseline chest CT images using the Goddard scoring system (possible scores for individual patients ranged from 0 to 24). Data on clinical characteristics and survival were retrospectively collected. Survivals were estimated using the Kaplan-Meier method and compared using the log-rank test. A multivariable Cox proportional hazard model was used to identify prognostic factors.

RESULTS

Most of the 149 patients were male (85.2%) and current/ex-smokers (87.2%). The median CT emphysema score was 4 (range, 0 to 23). Univariable analysis, patients with a higher CT emphysema score (≥8) had significantly poorer overall survivals (OS) than those with lower scores (5.0 12.3 months, P<0.001). Multivariable analysis showed a higher CT emphysema score (treated as a continuous variable) was a significant independent prognostic factor of poor survival [hazard ratio (HR), 1.85; 95% confidence interval (CI), 1.14 to 3.00; P=0.012], along with extensive stage (HR, 2.27; 95% CI, 1.45-3.53; P<0.001), elevated lactate dehydrogenase (LDH) (HR, 1.52; 95% CI, 1.03-2.23; P=0.034), and supportive care only (HR, 6.46; 95% CI, 3.64-11.48; P<0.001).

CONCLUSIONS

Emphysema severity, as determined by baseline CT, is significantly associated with poor prognosis in SCLC.