Table 1.

Mycosis fungoides variants recognized by the World Health Organization/European Organization for Research and Treatment of Cancer

MF Subtype	Clinical Presentation	Immunophenotype	Histology
Folliculotropic MF	Predilection for head/neck Alopecic skin lesions Follicular papules; Acneiform/comedonal-like papules or nodules (see Fig. 4)	CD41CD31 T-cell Admixed CD30 1 blasts	Perivascular and periadenexal lymphocytic infiltrates with infiltration of follicular epithelium (folliculotropism); variable infiltration of eccrine sweat glands by atypical lymphocytes with sparing of epidermis; follicular mucinosis
Pagetoid reticulosis	Predilection for extremities Localized psoriasiform patch or plaque Indolent clinical behavior	CD41CD31 T-cell or CD81CD31 T-cell CD30 often positive	Hyperplastic epithelium with marked pagetoid-like atypical lymphocytes; dermis with mixed reactive lymphocytes and histiocytes
Granulomatous slack skin	Predilection from axillae and groin Lax pendulous skin Indolent clinical behavior	CD41CD31 T-cell	Dense granulomatous dermal infiltrates of atypical lymphocytes, macrophages, many multinucleated giants cells; destruction of elastic tissue

Data from Willemze R, Jaffe ES, Burg G, et al. WHO-EORTC classification for cutaneous lymphomas. Blood 2005;105(10):3768–85.