Other conditions that simulate basal cell carcinoma include ameloblastoma (a dental tumor inside the mouth), cloacogenic carcinoma (anus), hair follicle tumors, sweat gland tumors, and sebaceous gland tumors.
The histopathology of metastatic breast cancer can resemble sclerosing or infiltrating basal cell carcinoma.
Pleomorphic basal cell carcinoma, which is essentially a BCC with giant atypical cells, behaves like any other BCC. Photos courtesy Dr. Ronald P. Rapini