Cutaneous Hemepath

Question 1

Spectrum of CD30+ lymphoproliferative disorders of the skin

Answer 1

Lymphomatoid pustulosis (LYP) to primary cutaneous anaplastic large cell lymphoma (PC-ALCL), with intermediate cases

LYP type A, LYP type B, LYP type C, Intermediate LYP-PC-ALCL, PC-ALCL

Question 2

Lymphomatoid pustulosis

Answer 2

Type of CD30+ lymphoproliferative disorder of the skin

Is itself benign – 5 year survival is 100% and there is a 40% chance of spontaneous remission – but 20% will eventually progress to malignancy, including mycosis fngoides, Hodgkin lymphoma, or a CD30+ T cell lymphoma

Type A/C immunophenotype: CD30+, CD3+. CD4+, CD2+, CD5+, TIA-1+, granzyme +. CD8-, CD7-, CD6-. May lose CD3 expression.

Type B immunophenotype: Same as above, but CD30-.

Question 3

Primary cutaneous anaplastic large cell lymphoma (PC-ALCL)

Answer 3

Mostly affects adults, middle-aged. Presents as a solitary, rapidly growing nodule, which may ulcerate. 5y survival is 90%, and interstingly there is up to 40% spontaneous remission, as in LYP.

Composed of atypical, large, anaplastic-appearing lymphoid cells. Cells grow in sheets, w/ frequent mitotic figures. Clusters of reactive lymphocytes are scattered throughout.

Immunophenotype: CD2+, CD3+, CD4+, CD30+, TIA-1+, granzyme +, perforin +. ALK-, EMA-. Loss of T cell markers is common.