Abstract
An autoantibody response against a breast carcinoma tumour specific neoantigen is described. The antigen, which was present in 6 of 11 breast carcinomata examined, was shown to have similarities to the T antigen of DNA virus induced animal tumours. In addition a different antigen (or antigenic determinant) was shown to be present in one breast carcinoma. This was not strictly tumour specific, being present in lower concentration in normal breast from the same individual.