Sclerosing polycystic adenosis of parotid gland with dysplasia and ductal carcinoma in situ: Report of three cases with immunohistochemical and ultrastructural examination

We describe three cases of sclerosing polycystic adenosis (SPA) of the parotid gland, a salivary condition analogous to fibrocystic disease of the breast. For the first time, immunoreactivity for oestrogen and progesterone receptors was demonstrated, suggesting a possible participation of hormone stimulation in its pathogenesis. In addition, all our cases showed foci of dysplasia of the ductal epithelium, which in one case was severe enough to amount to carcinoma in situ. This feature that has not previously been reported in SPA.