Smooth Muscle Antibody in Malignant Disease

Abstract

Smooth muscle antibody at titres of 1/10 or more was found in 54 (67·5%) out of 80 patients with malignant disease and in 9 (20%) out of 46 controls. The incidence of S.M. antibody ranged from 18/30 (60%) in malignant melanoma to 7/8 (83%) in carcinoma of the ovary. The presence of this antibody is possibly related to changes in the malignant cell membrane. A new antibody directed at an antigen presumed to be located in bile canaliculi among other sites is described.