Table 1
Interpretation of immunohistochemistry
| TdT | CD3 | CD4 | CD8 | GB/P | TIA1 | CD56 | EBV | CD30 | ALK | Characteristic feature(s) | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| *The T cell origin of this entity is disputed; †these tumours are usually CD57+. | |||||||||||
| ALCL, anaplastic large cell lymphoma; EBV, Epstein-Barr virus; GB, granzyme B; HTLV1, human T cell lymphotropic virus 1; NK, natural killer; NOS, not otherwise specified; P, perforin; PLL, prolymphocytic leukaemia; TdT, terminal deoxynucleotidyl transferase; +, positive; −, negative; +/−, usually positive, sometimes negative; −/+, usually negative, sometimes positive. | |||||||||||
| Predominantly leukaemic | |||||||||||
| Precursor T lymphoblastic leukaemia | + | + | +/− | +/− | − | − | − | − | − | − | Frequent presentation with mediastinal mass |
| T cell PLL | − | + | +/− | −/+ | − | − | − | − | − | − | Multi-organ involvement including the skin |
| T cell large granular lymphocytic leukaemia | − | + | −/+ | +/− | + | + | +/−* | − | − | − | Indolent behaviour |
| Aggressive NK cell leukaemia | − | + | − | − | + | + | + | + | − | − | Multi-organ involvement, highly aggressive |
| Adult T cell lymphoma/leukaemia (HTLV1+) | − | + | + | − | − | − | − | − | +/− | − | Usually widely disseminated, very rare in non-endemic areas |
| Predominantly extranodal | |||||||||||
| Extranodal NK/T cell lymphoma, nasal type | − | + | − | − | + | + | + | + | −/+ | − | Nearly always primary nasal localisation |
| Enteropathy-type T cell lymphoma | − | + | − | −/+ | + | + | −/+ | −/+ | −/+ | − | Usually, but not always associated with coeliac disease |
| Hepatosplenic γλ T cell lymphoma | − | + | − | − | − | + | + | − | − | − | Involvement of liver, spleen, and bone marrow |
| Predominantly cutaneous | |||||||||||
| Blastic NK cell lymphoma† | −/+ | − | + | − | −/+ | −/+ | + | − | − | − | Difficult distinction from T cell acute lymphoblastic leukaemia and myeloblastic leukaemia |
| Subcutaneous panniculitis-like T cell | − | + | − | + | + | + | −/+ | − | − | − | Rimming of adipocytes |
| Mycosis fungoides/Sezary syndrome | − | − | + | −/+ | −/+ | −/+ | − | − | − | − | Epidermotropism and Pautrier abscess formation |
| ALCL primary cutaneous | − | −/+ | +/− | −/+ | +/− | +/− | − | − | + | − | Distinction with lymphomatoid papulosis only on basis of clinical behaviour |
| Predominantly nodal | |||||||||||
| ALCL systemic | − | −/+ | +/− | −/+ | +/− | +/− | − | − | + | +/− | ALK positive cases demonstrate favourable clinical outcome |
| Peripheral T cell lymphoma, NOS | − | + | +/− | −/+ | − | − | − | − | +/− | − | Usually generalised disease |
| Angio immunoblastic T cell lymphoma | − | + | + | + | − | − | − | + | − | − | Aggregates of CD21 positive dendritic cells, outside follicle centres. EBV positive B cells |
