Table 1.
International Society for Cutaneous Lymphomas/European Organization for Research and Treatment of Cancer classification of mycosis fungoides/Sézary syndrome.
| TNMB Stages Definition | |
|---|---|
| Skin (T) | |
| T1 | Patches, papules, and or plaques covering <10% body surface area (BSA) T1a patch only T1b plaque ± patch |
| T2 | Patches, papules, and/or plaques covering ˃10% BSA T2a patch only T2b plaque ± patch |
| T3 | One or more tumors (at least one 1 cm diameter) solid or nodular lesion with evidence of depth and/or vertical growth |
| T4 | Confluence of erythema covering ˃80% BSA |
| NODE (N) | |
| N0 | No clinically abnormal peripheral lymph nodes, biopsy not required |
| N1 | Clinically abnormal peripheral lymph nodes, histopathology Dutch grade 1 or NCI LN0–2 (Table 2) N1a clone negative N1b clone positive |
| N2 | Clinically abnormal peripheral lymph nodes, histopathology Dutch grade 2 or NCI LN3 (Table 2) N2a clone negative N2b clone positive |
| N3 | Clinically abnormal peripheral lymph nodes, histopathology Dutch grade 3–4 (Table 2) or NCI LN4 (Table 3), clone positive or negative |
| Nx | Clinically abnormal peripheral lymph nodes, no histopathologic confirmation |
| VICERAL (M) | |
| M0 | No visceral organ involvement |
| M1 | Visceral involvement (must have pathology, and organ is to be specified) |
| BLOOD (B) | |
| B0 | Absence of significant blood involvement: <5% of blood lymphocytes are Sézary cells B0a clone negative B0b clone positive |
| B1 | Low blood tumor burden: >5% of peripheral blood lymphocytes are Sézary cells but does not meet criteria for B2 disease B1a clone negative B1b clone positive |
| B2 | High blood tumor burden: ˃1000/µL Sézary cells with positive clone in blood (matching clone in skin) or positive clone. |
| DUTCH GRADE SYSTEM | |
| Grade1 | Dermatopathic lymphadenopathy (DL) |
| Grade2 | Early involvement by mycosis fungoides (MF), presence of cerebriform nuclei larger than 7.5 μm |
| Grade3 | Partial effacement of lymph node architecture; many atypical cerebriform mononuclear cells (CMCs) |
| Grade4 | Complete effacement of lymph node architecture |
| NCI LN GRADE SYSTEM | |
| LN0 | No atypical lymphocytes |
| LN1 | Occasional and isolated atypical lymphocytes not arranged in clusters |
| LN2 | Many atypical lymphocytes or in 3–6 cell clusters |
| LN3 | Many atypical lymphocytes or in 3–6 cell clusters |
| LN4 | Partial/complete effacement of nodal architecture by atypical lymphocytes or frankly neoplastic cells |