We found normal expression of FHIT protein in all nonproliferative lesions, but underexpression in 2% of proliferative lesions without atypia, 10% of proliferative lesions with atypia, 0% of lobular carcinoma in situ, 33% of ductal carcinoma in situ and 41% of invasive carcinomas (Table 1). Here, FHIT is linked to ductal breast carcinoma in situ.