Flow cytometric and histological analysis of ductal carcinoma in situ of the breast.

Using archival paraffin wax embedded tumour we have investigated histological grade, DNA ploidy, S phase fraction and proliferative index in 74 patients with symptomatic ductal carcinoma in situ (DCIS) of the breast. Nine patients developed local recurrence, six invasive in character. No patients with the cribriform subtype of DCIS developed local recurrence. The cribriform subtype showed a significantly lower rate of DNA aneuploidy and a lower proliferative index than the other subtypes. Cribriform tumours were almost exclusively well differentiated in contrast with the comedo and solid variants. Our results suggest the cribriform variant is less aggressive than other subtypes of DCIS. This has possible implications for management of these lesions.