Cytological Diagnosis of Bilateral Breast Implant‐Associated Lymphoma of the ALK‐Negative Anaplastic Large‐Cell Type. Clinical Implications of Peri‐Implant Breast Seroma Cytological Reporting

The cytological examination of peri-prosthetic breast effusions allowed the diagnosis of bilateral breast-implant ALK-negative anaplastic large cell lymphoma (BI-ALCL) in the case reported. Ten years after reconstructive surgery with bilateral breast implants, a large unilateral seroma developed and was cytologically analyzed. The presence of CD30 and CD4-positive large-sized atypical lymphoid cells exhibiting horseshoe-shaped nuclei and a brisk mitotic activity rendered the diagnosis of BI-ALCL. Similar cells were seen in the peri-prosthetic fluid intraoperatively collected from the contralateral breast. Although initial histological analysis of the capsulectomy specimens showed unilateral tumor, the cytological findings prompted a more thorough tissue sampling, resulting in the diagnosis of bilateral disease. BI-ALCL usually follows an indolent clinical course; however, there are reported cases with an aggressive behavior. While the presence of bilateral disease is a putative risk factor for a bad prognosis, the small number of cases reported precludes a definitive assessment of this risk. Since most BI-ALCL present with late seromas, cytologic analysis of these effusions in women with breast implants should be mandatory. Cytology is a safe tool for diagnosis and follow-up of patients with breast implant-related late seromas, sometimes proven more sensitive than histological analysis. Complete bilateral capsulectomy and a detailed histological analysis should follow a cytological diagnosis of BI-ALCL in a breast effusion in order to avoid false negative diagnoses. Our case constitutes the first published report of a bilateral BI-ALCL diagnosed by cytology. Diagn. Cytopathol. 2016;44:623-627. © 2016 Wiley Periodicals, Inc.