Tuberc Respir Dis.  2025 Apr;88(2):334-341. 10.4046/trd.2024.0056.

Better Chemotherapeutic Response of Small Cell Lung Cancer in Never Smokers than in Smokers

• Park HY
• Oh HJ
• Park HK
• Yoon JY
• Yoon CS
• Kho BG
• Kim TO
• Shin HJ
• Park CK
• Kwon YS
• Kim YI
• Lim SC
• Kim YC
• Oh IJ

• KMID: 2566188
• DOI: http://doi.org/10.4046/trd.2024.0056

Abstract

Background
Small cell lung cancer (SCLC) is called ‘smoker’s disease’ because it is strongly associated with smoking and most cases occur in smokers. However, it can also occur in never smokers. We investigated the clinical features of never smokers with SCLC and compared their treatment outcomes with those of smokers with SCLC.
Methods
We retrospectively reviewed the clinical data of patients who had proven SCLC and had received chemotherapy at a single cancer center between July 2002 and April 2021.
Results
Of 1,643 patients, 1,416 (86.2%) were enrolled in this study. A total of 162 (11.4%) and 1,254 (88.6%) patients were never smokers and smokers, respectively. There were more female never smokers than smokers (n=130; 80.2% vs. 79, 6.3%, p=0.000), and the incidence of ischemic heart disease was lower among never smokers than among smokers (4/1,416, [2.5%] vs. 83/1,416 [6.6%], p=0.036). Never smokers showed less symptoms at diagnosis than smokers (80.9% vs. 87.2%, p=0.037); however, they showed more toxicity after first-line treatment (61.7% vs. 47.8%, p=0.001). The objective response rate (ORR) was significantly higher in never smokers (74.1% vs. 59.6%, p=0.000). In the multivariate analysis, never smoking and second-line treatment were associated with a better ORR. However, progression-free survival and overall survival were not significantly different between never smokers and smokers.
Conclusion
In conclusion, never smokers accounted for 11.4% of patients with SCLC. They had distinguishing clinical characteristics and showed better chemotherapeutic responses than smokers.

Keyword

Never Smoker; Response Rate; Small Cell Lung Cancer