The impact of smoking status on the behavior and survival outcome of patients with advanced non-small cell lung cancer: a retrospective analysis.
OBJECTIVE
There are fundamental differences in characteristics between smokers and nonsmokers with non-small cell lung cancer (NSCLC). We aim to study the impact of smoking status on the behavior of the disease, and to identify differences in outcome between the two groups.


METHODS
A retrospective analysis was done of patients with NSCLC seen during the period from January 1999 to August 2002. Clinical characteristics, survival outcome, and response to treatment were reviewed and compared between the smokers and nonsmokers.


METHODS
Department of Medical Oncology, National Cancer Center.


RESULTS
Of 317 patients analyzed, 117 patients (36.3%) were nonsmokers. Among the nonsmokers, 74.5% had adenocarcinoma and 73.9% were women. The smokers had poorer performance status, reported more weight loss, and had a higher mean age at diagnosis of almost 8 years than nonsmokers. One hundred eighty-seven patients (59%) had died as of December 31, 2002. The nonsmokers had a longer median survival, although this was not statistically significant. There were no statistically significant differences in survival and response to chemotherapy between the two groups after adjusting for known prognostic factors.


CONCLUSIONS
Despite the known differences in mutational spectra and clinical characteristics between smokers and nonsmokers with NSCLC, no differences in terms of response to chemotherapy and survival outcome were observed. This could imply that this disease is equally aggressive in these two groups. More research is needed to further delineate and characterize the differences between these two etiologically different forms of NSCLC.
Toh
Chee-Keong
CK
Department of Medical Oncology, National Cancer Center, 11 Hospital Drive, Singapore 169610.
Wong
Ee-Hwee
EH
Lim
Wan-Teck
WT
Leong
Swan-Swan
SS
Fong
Kam-Weng
KW
Wee
Joseph
J
Tan
Eng-Huat
EH
D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000209:etiology / Q000401:mortality*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000209:etiology / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects*; D015996:Survival Rate; D016896:Treatment Outcome; D015431:Weight Loss