Lung cancer is uncommon in individuals age 40 or less. We reviewed the
Cancer Registry files of the Ben Taub General Hospital (Houston, TX)
from 1971 to 1989 and identified 1678 patients with a documented diagn
osis of lung cancer. Among these 1678 patients, 50 (2.98%) were age 40
or less. Thirty-five (70%) of the 50 patients were men and 15 (30%) w
ere women. Their median age was 37 (range of 24 to 40). A smoking hist
ory was available in 37 patients. Thirty-five (94.5%) of the 37 patien
ts who were smokers had a >20-pack per year history of smoking. Four p
atients were intravenous drug abusers, and one of these four tested po
sitive for the immunodeficiency virus. Twenty-seven (54%) had adenocar
cinoma, eight (16%) had squamous cell carcinoma, and six (12%) had oth
er nondescript, nonsmall-cell carcinoma types. In contrast, the propor
tion of adenocarcinoma for the (all-age) group of 1678 patients with l
ung cancer was 28.2%. This difference in the proportion of adenocarcin
oma between the two age groups was statistically significant (Pearson'
s Chi2, 13.7039, p <0.0005). Thirty-one (77.5%) of the 50 patients had
unresectable disease at diagnosis (12 had stage IIIb and 19 had stage
IV). The median survival from diagnosis was 26 weeks. These findings
suggest that (1) smoking is an important risk factor for this subset o
f young patients, (2) the proportion of adenocarcinoma is higher in th
e young compared with the entire group of lung cancer patients, which
included patients of all ages, and (3) young patients tend to present
with advanced disease at diagnosis, resulting in an extremely poor sur
vival.