In vitro tetraploidy in patients with non-hereditary colorectal adenoma and carcinoma. Support for a genetic influence on the pathogenesis of colorectal carcinoma.

One hundred and seventy-two patients (76 patients with colorectal cancer, 46 with adenoma of the colon or rectum, and 50 controls) were investigated for in vitro tetraploidy in dermal fibroblast monolayer cultures. The incidence of increased in vitro tetraploidy (IVT) among patients with adenoma or carcinoma was significantly different from that of controls. There was no difference in the incidence of IVT between the adenoma patients and those with colorectal cancer. IVT was investigated among different subgroups of adenoma and colorectal cancer patients and was only found to be related to an inherited tendency to colorectal cancer.