Differences in histology between first and second primary lung cancer

Abstract

Data from the Surveillance, Epidemiology, and End Results (SEER) Program were used to compare the histological distribution of second lung cancer following an initial cancer of the lung, head and neck, and breast to primary lung carcinoma occurring as a first cancer. Following initial head and neck cancer or initial squamous cell carcinoma of the lung, the proportion of second primary lung cancer which was of squamous cell histology rose dramatically, while the proportion of pulmonary adenocarcinomas rose following initial adenocarcinoma of the lung. The histological distribution of lung cancer following an initial breast cancer in women was similar to the distribution of de novo lung cancer in women. These results persisted as the time interval between diagnosis of the two primaries was increased from 12 to 48 months. We conclude that the histology of a second primary lung cancer following an initial cancer of the lung or head and neck tends to repeat the histology of the initial cancer (field effect), and this observation is not likely to be due to misdiagnosis of a recurrence of the initial cancer.