Review of scalp alopecia due to a clinically unapparent or minimally apparent neoplasm (SACUMAN).

Neoplastic cells, both malignant and benign, local occurring and metastatic, can cause alopecia of the scalp. However, the infiltration of neoplastic cells is sometimes not florid; a condition known as "scalp alopecia due to a clinically unapparent or minimally apparent neoplasm" (SACUMAN). Neoplastic cells can nevertheless destroy hair follicles by inducing fibroplasias via inflammatory mediators, attracting inflammatory cells and/or replacing normal cellular populations. The infiltrative nature of such an alopecia can be unapparent or only minimally apparent. The most common neoplasm in which an uncomplicated, minimally or unapparent scalp alopecia occurs and no infiltrate of cancer is suspected is metastatic breast carcinoma. Other causes include squamous and basal cell carcinomas, angiosarcoma, gastric carcinoma, placental site tromphoblastic tumor, and mycosis fungoides. Syringoma-like proliferations can underlie alopecia. It is unclear whether these proliferations are true syringomas or normal findings. In conclusion, neoplasms causing cicatricial alopecia of the scalp are very rare, so generalizations from the limited number of case reports are of uncertain importance. Moreover, it is likely that many cases of neoplasms causing cicatricial alopecia of the scalp are diagnosed as inflammatory alopecia and not neoplasms, thus depriving us of a full accounting and understanding of this entity. Dermatologists must be aware that in rare cases a bland scalp alopecia can represent a new or recurring, local or metastatic neoplasm.