Table 1.

International Society for Cutaneous Lymphomas (ISCL)/European Organization of Research and Treatment of Cancer (EORTC) tumor, node, metastases (TNM) classification of cutaneous lymphomas other than mycosis fungoides (MF)/Sézary syndrome (SS).

Skin (T)	T1		Solitary Skin Involvement
		T1a	Solitary lesion <5 cm in diameter
		T1b	Solitary lesion ≥5 cm in diameter
	T2		Regional skin involvement: multiple lesions limited to one body region or two contiguous body regions
		T2a	All disease encompassing a <15 cm diameter circular area
		T2b	All disease encompassing a 15 to ≤30 cm diameter circular area
		T2c	All disease encompassing a ≥30 cm diameter circular area
	T3		Generalized skin involvement
		T3a	Multiple lesions involving two noncontiguous body regions
		T3b	Multiple lesions involving ≥3 body regions
Lymph nodes (N)	N0		No clinical or pathologic lymph node involvement
	N1		Involvement of one peripheral or central lymph node region that drains in an area of current or prior skin involvement
	N2		Involvement of ≥2 peripheral or central lymph node regions or involvement of any lymph node region that does not drain in an area of current or prior skin involvement
	N3		Involvement of central lymph nodes
Viscera (M)	M0		No evidence of extracutaneous non-lymph node disease
	M1		Extracutaneous non-lymph node disease present

Adapted from Kim YH, Willemze R, Pimpinelli N, et al. TNM classification system for primary cutaneous lymphomas other than mycosis fungoides and Sézary syndrome: a proposal of the International Society for Cutaneous Lymphomas (ISCL) and the Cutaneous Lymphoma Task Force of the European Organization of Research and Treatment of Cancer (EORTC). Blood 2007;110(2):480. [21].