ERBB2 and ductal breast carcinoma in situ: Since HER-2 overexpression is reported in up to 80% of DCIS tumours and is associated with high-grade phenotype (Allred et al, 1993; Bobrow et al, 1995; Suo et al, 2001), we investigated the association of COX-2 and HER-2 expression in DCIS.