[Lung cancer in patients under 40 years of age: a different problem?]

Less than 5% of the cases of lung cancer diagnosed are found in young patients. Although there are few studies concerning this problem it has been suggested that in this age group the behavior of the disease is more aggressive and the prognosis worse.

In order to study the clinical characteristics, histology, and evolution of bronchogenic lung cancer diagnosed in patients under 40 years of age the data of 56 patients with this neoplasm and age was compared with those obtained from 500 patients, equal to or over 40 years of age, diagnosed during the same period of time.

The proportion of males/females among the patients under 40 years of age was 4:1, while in those patients over this age it was 13:1 (p less than 0.001). Epidermal cancer was the most frequent histological variety found among the patients over 40, while microcytic cancer of the lung was more frequent in those under 40 (p less than 0.05). In the group of patients under 40, 8 patients under 30 had special characteristics: male/female proportion 1:1 (p = 0.078), histological predominance of the adenocarcinoma variety and undifferentiated carcinoma of large cells (p = 0.008) and lower number of smokers (p = 0.035). The time of evolution of symptoms, the extension of the disease at the time of diagnosis and survival of the patients over or under the age of 40 was similar.

Despite the presentation of special characteristics in young patients with bronchogenic lung cancer, the behavior of the disease is similar to that observed in other age groups.