Can hamartoma of the breast be distinguished from fibroadenoma using fine-needle aspiration cytology?

In an attempt to determine if it is possible to distinguish hamartoma of the breast from fibroadenoma using fine-needle aspiration cytology, we reviewed the cytological slides of 13 histopathologically confirmed cases of hamartoma of the breast and compared them with the cytological features of 13 histologically confirmed fibroadenomas. In each case, we studied the epithelial and stromal features. Cytologic characteristics were retrospectively evaluated in a semiquantitative manner. In conclusion, the finding of intact lobular units and a relative paucity of stroma may suggest the diagnosis of hamartoma.