Adenocarcinoma of the lung in young patients: the M. D. Anderson experience

Surveillance, Epidemiology, and End Results (SEER) data for the years 1973-1992 documented that patients age < 50 years presented with more advanced disease. Because of the increase in the incidence rate of lung adenocarcinoma in the past few decades and the presentation of more advanced disease in young patients, this study was performed to determine whether differences in survival exist between younger and older patients with this disease.

The authors reviewed the experience of the University of Texas M. D. Anderson Cancer Center between 1985-1994, encompassing 157 patients age < 40 years of 4097 patients registered with adenocarcinoma of the lung. For comparison, 157 patients age > 50 years with lung adenocarcinoma were selected; these patients were matched for gender, stage of disease at presentation, and definitive therapy modality to assess survival differences more accurately. Data regarding exposure to second-hand smoke were not collected secondary to lack of documentation in the charts reviewed.

There were no significant differences between the 2 groups with regard to the overall survival rate (P = 0.34) or time to progression (P = 0.43). Smoking status (current vs. former vs. never-smoker) was not found to be predictive of survival in either the younger group (P = 0.51) or the older group (P = 0.92).

The data from the current study indicate that overall survival and disease free survival rates were not significantly different in these two groups. Thus, the younger patient population should be treated similarly to the older patient population. However, a surprisingly high percentage of younger patients were female (45%) and had never smoked (27%), suggesting that risk factors other than active smoking may be involved in lung carcinogenesis in these patients.