Elaboration of human chorionic gonadotropin by lung tumors: an immunocytochemical study.

The highly sensitive peroxidase-antiperoxidase immunocytochemical method was used to demonstrate the presence of the beta-subunit of human chorionic gonadotropin (HCG) within paraffin sections of human lung tumors of diverse histologic patterns. Of the 61 tumors studied, 51 (84%) displayed HCG-like immunoreactivity. This is a much higher incidence than was expected considering studies by other investigators in which serum samples from patients with lung cancer were assayed for HCG. Our results are, however, consistent with data from studies by other investigators in which tumor extracts were assayed for HCG. In addition, it was found that HCG production was often linked with glycogen storage within tumor cells. This may explain the association of HCG production with large-cell carcinomas of the lung, because these tumors often contain copious quantities of glycogen.