Cutaneous lymphomas

Question 1

Name 2 indolent primary cutaneous B cell lymphomas and IHC
Name 1 aggressive primary cutaneous B cell lymphoma

Answer 1

1. Primary cutaneous marginal zone lymphoma (BCL2+, monotypic plasma cells, CD5/10/cyclin D1 neg, no epidermotrophism, reactive germinal centres and no systemic disease at presentation)
2. Primary cutaneous follicle centre lymphoma (BCL6+, CD10/BCL2 - and neg for t(14:18) translocation; MUM1 neg, diffuse/nodular growth + disrupted CD21/35 meshworks); favours head and neck - seldom on legs.
3. PC- DLBCL, leg type: BCL2/MUM1/MYC/cytoplasmic IgM +; diffuse growth no CD21/35 disrupted follicular meshworks.

Question 2

Name:
5 indolent cutaneous T cell lymphomas + IHC
3 aggressive cutaneous T cell lymphomas + IHC

Answer 2

1. MF (CD2/3/54+, rarely CD8+, can be CD30+ advanced stage, (-) CD 7/8; persistent progressing lesions
2. Lymphomatoid papulosis (self-healing lesions, CD4/30+ most cases)
3. C-ALCL (CD4/CD30+, cytotoxic protein +, ALK neg; different morphology + clin presentation, +/- mcuosal involvement; epidermotrophism esp with DUSP22 rearrangement)
4. Primary cutaneous CD4+ small to medium T-cell lymphoproliferative disorder (CD3/4/ICOS/BCL6/CXCL13/PD1 +; neg cytotoxic markers/CD10/CD30) solitary erythematous nodule head/neck/upper trunk) -> admixed B cells!
5. Subcutaneous panniculitis-like T-cell lymphoma (CD2/5/8/perforin/granzym B/TIA1 +; (-) CD4/EBV/CD30

Aggressive
1. Sezary syndrome (CD3/4/PD1 +; expression of CD8- and loss of Tcell markers CXCL13/ICOS; loss of T-cell markers CD2/5/7)

2. Primary cutaneous epidermotrophic CD8+ T-cell lymphoma (CD8+, cytotoxic molecules +, CD2/5-, pagetoid reticulosis pattern, epidermal necrosis, striking pagetoid epidermotrophism).
3. Cutaneous Extra-nodal NK/T cell lymphoma, nasal type
4. Primary cutaneous gamma/delta T cell lymphoma (CD3/TCRγδ+ T cells; CD4/8/30 -)

Question 3

Name CD30+ cutaneous lymphomas (5)

Answer 3

1. LP
2. ALCL, primary cutaneous
3. ALCL, systemic (ALK+/-)
4. primary cutaneous EBV+ DLVCL
5. transformed MF