Primary Cutaneous Follicle Center Lymphoma

**Semantic type:** Neoplastic Process

**Definition:** A primary lymphoma of the skin composed of various numbers of small and large irregular neoplastic follicle center cells. Its morphologic pattern can be nodular, diffuse, or nodular and diffuse. It presents with solitary or grouped plaques and tumors, and it usually involves the scalp, forehead, or trunk. It rarely involves the legs. This type of cutaneous lymphoma tends to remain localized to the skin.

**Synonyms:** - Crosti's Disease - Cutaneous Follicle Center Lymphoma - Cutaneous Follicle Centre Lymphoma - Cutaneous follicle center lymphoma, unspecified site - PCFCL - Reticulohistiocytoma of the Dorsum