ISCL/EORTC revision to the classification of MF and SS
| TNMB classification . | . |
|---|---|
| Skin | |
| T1 | Limited patches,* papules, and/or plaques† covering <10% of the skin surface. May further stratify into T1a (patch only) vs T1b (plaque ± patch). |
| T2 | Patches, papules, or plaques covering ≥10% of the skin surface. May further stratify into T2a (patch only) vs T2b (plaque ± patch). |
| T3 | One or more tumors‡ (≥1-cm diameter). |
| T4 | Confluence of erythema covering ≥80% BSA. |
| Node | |
| N0 | No clinically abnormal peripheral lymph nodes§; biopsy not required. |
| N1 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grade 1 or NCI LN0-2. |
| N1a | Clone negative.|| |
| N1b | Clone positive.|| |
| N2 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grade 2 or NCI LN3. |
| N2a | Clone negative.|| |
| N2b | Clone positive.|| |
| N3 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grades 3-4 or NCI LN4; clone positive or negative. |
| Nx | Clinically abnormal peripheral lymph nodes; no histologic confirmation. |
| Visceral | |
| M0 | No visceral organ involvement. |
| M1 | Visceral involvement (must have pathology confirmation¶ and organ involved should be specified). |
| Blood | |
| B0 | Absence of significant blood involvement: ≤5% of peripheral blood lymphocytes are atypical (Sézary) cells.# |
| B0a | Clone negative.|| |
| B0b | Clone positive.|| |
| B1 | Low blood tumor burden: >5% of peripheral blood lymphocytes are atypical (Sézary) cells but does not meet the criteria of B2. |
| B1a | Clone negative.|| |
| B1b | Clone positive.|| |
| B2 | High blood tumor burden: ≥1000/µL Sézary cells# with positive clone.|| |
| TNMB classification . | . |
|---|---|
| Skin | |
| T1 | Limited patches,* papules, and/or plaques† covering <10% of the skin surface. May further stratify into T1a (patch only) vs T1b (plaque ± patch). |
| T2 | Patches, papules, or plaques covering ≥10% of the skin surface. May further stratify into T2a (patch only) vs T2b (plaque ± patch). |
| T3 | One or more tumors‡ (≥1-cm diameter). |
| T4 | Confluence of erythema covering ≥80% BSA. |
| Node | |
| N0 | No clinically abnormal peripheral lymph nodes§; biopsy not required. |
| N1 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grade 1 or NCI LN0-2. |
| N1a | Clone negative.|| |
| N1b | Clone positive.|| |
| N2 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grade 2 or NCI LN3. |
| N2a | Clone negative.|| |
| N2b | Clone positive.|| |
| N3 | Clinically abnormal peripheral lymph nodes; histopathology Dutch grades 3-4 or NCI LN4; clone positive or negative. |
| Nx | Clinically abnormal peripheral lymph nodes; no histologic confirmation. |
| Visceral | |
| M0 | No visceral organ involvement. |
| M1 | Visceral involvement (must have pathology confirmation¶ and organ involved should be specified). |
| Blood | |
| B0 | Absence of significant blood involvement: ≤5% of peripheral blood lymphocytes are atypical (Sézary) cells.# |
| B0a | Clone negative.|| |
| B0b | Clone positive.|| |
| B1 | Low blood tumor burden: >5% of peripheral blood lymphocytes are atypical (Sézary) cells but does not meet the criteria of B2. |
| B1a | Clone negative.|| |
| B1b | Clone positive.|| |
| B2 | High blood tumor burden: ≥1000/µL Sézary cells# with positive clone.|| |
NCI LN, National Cancer Institute Lymph Node; PCR, polymerase chain reaction; TCR, T-cell receptor; TNMB, tumor-node-metastasis-blood.
For skin, patch indicates any size skin lesion without significant elevation or induration. Presence/absence of hypo- or hyperpigmentation, scale, crusting, and/or poikiloderma should be noted.
For skin, plaque indicates any size skin lesion that is elevated or indurated. Presence or absence of scale, crusting, and/or poikiloderma should be noted. Histologic features such as folliculotropism or large-cell transformation (>25% large cells), CD30+ or CD30−, and clinical features such as ulceration are important to document.
For skin, tumor indicates at least one 1-cm diameter solid or nodular lesion with evidence of depth and/or vertical growth. Note total number of lesions, total volume of lesions, largest size lesion, and region of body involved. Also note if histologic evidence of large-cell transformation has occurred. Phenotyping for CD30 is encouraged.
For node, abnormal peripheral lymph node(s) indicates any palpable peripheral node that on physical examination is firm, irregular, clustered, fixed, or 1.5 cm or larger in diameter. Node groups examined on physical examination include cervical, supraclavicular, epitrochlear, axillary, and inguinal. Central nodes, which are not generally amenable to pathologic assessment, are not currently considered in the nodal classification unless used to establish N3 histopathologically.
A T-cell clone is defined by PCR or Southern blot analysis of the T-cell receptor gene.
For viscera, spleen and liver may be diagnosed by imaging criteria.
For blood, Sézary cells are defined as lymphocytes with hyperconvoluted cerebriform nuclei. If Sézary cells are not able to be used to determine tumor burden for B2, then 1 of the following modified ISCL criteria along with a positive clonal rearrangement of the TCR may be used instead: (1) expanded CD4+ or CD3+ cells with CD4/CD8 ratio of 10 or more, (2) expanded CD4+ cells with abnormal immunophenotype including loss of CD7 or CD26.