BIA-ALCL resembles CD30+ cutaneous LPD: ALK-, CD30+ anaplastic cells with an aberrant T cell phenotype; overexpression of oncogenes (JUNB, SATB1, pSTAT3, SOCS3) in lymphomatoid papulosis (LyP); frequent apoptosis; complete spontaneous regression in LyP and partial spontaneous regression in cutaneous ALCL.
SATB1 expression was identified in the CD30<sup>+</sup> anaplastic T cells in 11 of 12 (91.7%) lymphomatoid papulosis and 16 of 42 (38.1%) primary cutaneous anaplastic large-cell lymphoma cases.