2023 Volume 8 Issue 1 Pages 8-15
Breast implant-associated anaplastic large cell lymphoma（BIA-ALCL）is a CD30-positive T-cell neoplasm arising in association with breast prosthesis（usually silicone implant with textured surface）. Cytomorphology and immunophenotype of BIA-ALCL are similar to those of ALK-negative ALCL；however, accumulating evidence suggests that BIA-ALCL has distinct genetic features and gene expression profile as well as a unique clinical presentation. Neoplastic cells of BIA-ALCL exhibit anaplastic morphology with horseshoe-shaped or kidney-like nuclei and relatively abundant cytoplasm. Immunophenotypically, CD30 is strongly and uniformly expressed. The expression of pan-T-cell markers, such as CD3, CD5, and CD7, is frequently lost or diminished, whereas CD4 and CD43 are commonly positive. Genetically, BIA-ALCL is consistently negative for ALK，DUSP22， and TP63 rearrangements, corresponding to the triple negative subtype. Gene mutations resulting in activation of the JAK/STAT signaling pathway, such as gain-of-function STAT3 mutation, are common. Gene expression profiling revealed upregulation of hypoxia response pathway genes including overexpression of carbonic anhydrase IX（CA9）. As BIA-ALCL with limited stage is curable by complete resection of the implant and fibrous capsule, early, precise diagnosis should be performed by a collaboration of surgeons, radiologists, and pathologists.
