Dermatomyositis (DM) is characterized by an inflammatory myopathy and typical cutaneous lesions. In a retrospective study, 29 adult cases without overlap syndrome were reviewed. Our aim was to define predictive signs of cancer. Ten (four women, six men) of the 29 patients (35%) had DM associated with malignancy. The diagnosis of cancer was made concomitantly in six cases, more than year after (two cases), more than year prior to (two cases) the occurrence of DM. No extensive diagnosis procedures were necessary for identifying the tumors. A paraneoplasic evolution was certain for any patient, probable for six, improbable for fourth. For the group with malignancy: age was higher (P = 0.01), albumin lower (P = 0.04), C reactive protein higher (P = 0.0061). These parameters seem to have predictive value for the presence of malignancy.