Case 1: Spontaneous Regression

In 1994, a 32-year-old female underwent bilateral, subglandular breast augmentation and concomitant periareolar mastopexy using Mentor (Mentor Corp., Santa Barbara, CA), smooth, saline implants. A left sided post-operative wound infection was treated conservatively. She developed bilateral capsular contracture after some months.

In 2009, she underwent bilateral explantation and replacement with Silimed (Silimed, Rio de Janeiro), polyurethane foam-covered silicone gel implants in new submuscular pockets. The left capsule was heavily calcified and excised; the right capsule was retained. Her recovery was uneventful.

In May 2014, aged 51, she presented to her GP with a unilateral enlargement of the right breast. An ultrasound scan demonstrated the presence of a large seroma. She delayed seeking treatment for 8 months until January 2015 when she underwent aspiration. Cytology was diagnostic for BIA-ALCL with abundant atypical T cells that were CD30+ and ALK− (Figs. 1, ​,2).2). Culture was negative. Subsequent bone marrow aspirate, blood investigations and PET scan were normal. Two months later in March 2015, the aspiration was repeated. Most of the cells identified were benign macrophages and flow cytometry was normal. The very scant CD30+ cells identified (Fig. 3) were interpreted as representing a combination of benign activated lymphocytes, a recognised phenomenon [18–20] and very low level of lymphoma (< 5%). One month later in April 2015, she underwent breast implant explantation and capsulectomy. At surgery, occasional atypical lymphoid cells were identified on cytological examination of the greatly reduced residual seroma fluid (Fig. 4). The fluid was paucicellular, and there was insufficient cellular material for reliable immunohistochemical examination. Flow cytometry was non-diagnostic. Widely sampled histopathology of the capsule was normal, and capsular CD30 was negative (Fig. 5). The patient has since remained asymptomatic.

Case 1. Seroma cytology January 2015. Giemsa stain ×400. All the larger cells seen are tumour cells. Atypical cytological features include abundant finely vacuolated cytoplasm, marked nuclear pleomorphism, irregular nuclear membranes and polylobulated nuclei. A normal small lymphocyte (arrowed) allows easy comparison. The background comprises erythrocytes

Case 1. Cell block of seroma fluid January 2015. Haematoxylin & Eosin ×100. This lower power magnification demonstrates the marked cellularity of the sample. The inserts show that virtually every cell is positive for CD30 and negative for CD163 (a macrophage marker)

Case 1. Cell block of seroma fluid March 2015. Haematoxylin & Eosin ×100. The inserts show that now there are only scant CD30 positive cells and that most of the cells are CD163 positive benign macrophages

Case 1. Seroma cytology April 2015. Giemsa stain ×400. The fluid is remarkably more paucicellular than previous samples. This photomicrograph shows only scant larger cells with background cellular debris and a few small benign lymphocytes, indicating very low level of residual lymphoma. The sample was too paucicellular for a cell block

Case 1. Histological section of the implant capsule April 2015. Haematoxylin & Eosin ×100. There is a bland fibrous capsule with occasional reactive lymphoid aggregate (arrowed) and areas of pseudosynovial metaplasia. No capsular lymphoma is present. The inset shows that the reactive lymphoid aggregates are negative for CD30