Highly pleomorphic staphylococci as a cause of cancer.

An extensive historical literature exists suggesting that bacteria and other non-virus microorganisms cause cancer. Much of this literature stresses the likely involvement of highly pleomorphic bacteria in carcinogenesis. Pleomorphic bacteria exhibit a variety of morphological types, some of which are identical to other bacteria. In particular, bacteria that can express more than one morphology, including that normally associated with common species of Staphylococcus, have frequently been isolated from cancers. Not surprisingly, this has led to considerable confusion and ridicule. The literature linking highly pleomorphic bacteria with carcinogenesis is presented here in an attempt to add weight to the view that bacteria, notably those expressing the morphology of common species of staphylococci, cause cancer.