Correlation between in vitro tetraploidy in skin fibroblasts and development of sporadic colorectal carcinomas.

In vitro tetraploidy (IVT) in skin fibroblasts cultures measured by flow cytometry was compared with histological type and degree of dysplasia in 22 patients with adenomas of the colon and rectum. Furthermore, IVT was compared with stage and differentiation in 36 patients with carcinoma of the colon and rectum. In vitro tetraploidy in skin fibroblasts was correlated to type as well as dysplasia in adenomas and differentiation in carcinomas but was not correlated to Dukes' stage in carcinomas. Skin fibroblast genetic instability, expressed as increased IVT (IVT+), has been reported to reflect a genetic predisposition to colorectal cancer in the hereditary nonpolyposis colorectal cancer syndrome. Because IVT+, which appears to be associated with the progression of adenomas to carcinomas, also is found in many of the non-syndrome colorectal cancers, we suggest that development of colorectal cancer is considerably influenced by the constitutive genetic instability of the autosomal dominant colorectal cancer syndromes.