BIA-ALCL schematic and TNM staging. (A) The schematic demonstrates that BIA-ALCL typically presents in the seroma surrounding the breast implant. The lymphoma is usually contained within the fibrous capsule and distinct from breast parenchyma. BIA-ALCL typically is isolated to within the fluid and/or inner wall of the capsule, although invasion into or beyond the capsule is less commonly seen and associated with a worse prognosis. (B) This can be seen histologically or on gross review of the pathology at the time of surgery. (C) Clinical and pathologic staging of BIA-ALCL follows the MD Anderson Solid Tumor Staging System modeled after the American Joint Committee on Cancer TNM stages. Using this system, BIA-ALCL patients have a spectrum of disease from IA (35.6%, effusion only), IB (11.5%), IC (13.8%), IIA (25.3%), IIB (4.6%), III (9.2%), to stage IV (0%). Adapted from Clemens et al⁷  with permission.