Synchronous primary lung cancers: prevalence in surgical material and clinical implications.

BACKGROUND The prevalence of synchronous primary lung neoplasms in surgical resection specimens was assessed. The associated clinical features and prognostic implications were investigated. METHODS All surgical resections for lung cancer performed during seven years were reviewed. Synchronous tumours were defined by the presence of more than one tumour mass in the lung, by differences in histological subtype, by the presence of separate bronchial origins, or by differences in DNA stemlines. Clinical data were abstracted from case notes and information from the tumour registry. RESULTS Just under 2% of all surgical specimens in the study period contained more than one primary carcinoma. The patients did not differ clinically from the general population of patients having surgery for lung cancer. The overall prognosis was poor (mean survival 27 months) but was significantly better for patients with synchronous squamous carcinomas (mean survival 49 months). CONCLUSION Synchronous primary lung carcinomas are associated with a poor prognosis except in patients having tumours only of squamous histological type.