Interstitial granulomatous drug reaction following intravenous ganciclovir

strated in breast carcinomas, and suggested its correlation with poor prognosis. We therefore addressed whether EMPD exhibits a similar stromal CD10 expression. In the present study, the stromal CD10 expression was obviously correlated with Ki-67-positive proliferative capacity and invasiveness of Paget cells in EMPD. In four of 19 cases of in situ EMPD, weak to strong CD10 expression was detected in the stromal cells of peritumoral dermis; also, > 30% of Paget cells expressed Ki-67 in five of 19 instances of in situ EMPD. These instances of in situ EMPD might be considered to be in a pre-invasive state. As our study shows only histopathological results, further investigations should be done to determine the significance of stromal CD10 expression. The invasive and ⁄or metastatic potential of several types of cancers is regulated by interactions between cancer cells and stromal cells in the microenvironment, involving stimulatory and ⁄or inhibitory factors that regulate cellular adhesion, migration and gene expression. CD10 may be induced by the cancer cells through soluble factors similar to other metalloproteinase families. Some experimental data indicate that CD10 may be a potential target for new cancer therapies, as it is involved in cleavage of doxorubicin, a critical component of many cancer treatment protocols, and results in chemoresistance. Inhibition of CD10 enzymatic activity may enhance the antitumour efficacy of traditional chemotherapeutic regimens. Our observation that CD10 was expressed in the stromal cells of more advanced EMPD may emphasize that the stromal cells may also have a very important role in the progression of EMPD.