The median grade of the sarcomatous components of the tumour was 4; with regard to the dominant component of the tumours, adenocarcinoma was the dominant histological pattern in 7 cases and sarcoma was the dominant component in 14 cases; with regard to the immunohistochemistry of the tumours, positive immunohistochemical staining cytoplasmic reactivity was revealed for prostate specific antigen or keratin in 16 of 16 cases in the adenocarcinoma component. This evidence concerns the gene KLK3 and sarcoma.