in the Axilla and Axillary Siliconomas Assessment and Treatment Algorithm

Fig. 14.1

Silicones in the axilla. Mammography showing silicone in the axilla. Bilateral mammography is observed in an oblique view, in breasts with prosthetic implants from which there is abundant silicone that not only spread through the breast but also migrated to the axilla

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig2_HTML.png — Fig. 14.2

Silicone in the axilla. Mammography showing more detail of the axillary region. Note that a large part of the axilla is filled with silicone

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig3_HTML.jpg — Fig. 14.3

Silicone in the axilla. The lower axillary region is already affected by the migration of silicone

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig4_HTML.jpg — Fig. 14.4

Silicone in the axilla. Mammogram where opacities are seen as a result of the past injection of silicone

The quantity of silicone is usually minimal, affecting no more than two or three lymph nodes. Any larger quantity of silicone or number of affected lymph nodes is usually accompanied by clinical symptoms when discovered.

Ultrasound is also useful in these circumstances, typically revealing very dense images characterized by regular edges and a marked acoustic shadow; this has been called a “snowstorm” or “broken television” appearance.

The aforementioned methods are usually sufficient to make a diagnosis of axillary siliconomas. Magnetic resonance imaging, sestamibi-28 scintimammography, or 18F-FDG PET/CT can be used when there are doubts about the etiology of the axillary formation. As expressed by D’hulst, however, employing 18F-FDG PET/CT to identify reactive adenitis due to silicones in lymph nodes is not as specific as performing mammography. A percutaneous biopsy should always be considered when the potential presence of carcinoma metastases is still in doubt [30].

Pathology

Granulomatous Lymphadenopathy Due to Silicones

The migration of small silicone particles via the lymphatic route to lymph nodes can produce granulomatous lymphadenopathy [3, 31, 32]. The most frequently affected lymph nodes are axillary lymph nodes, but migration can also occur to other lymph node clusters, like supraclavicular and mediastinal nodes [33, 34]. Such adenopathy can occur in two clinical contexts: in a patient who has had a prosthesis implanted for purely aesthetic reasons; or in a patient whose prosthesis was implanted during postmastectomy breast reconstruction. In the latter situation, in addition to the patient’s natural anguish, there is the very real possibility that the adenopathy represents metastatic spread of a previously treated carcinoma.

Silicone lymphadenopathy can hinder the intraoperative study of the “sentinel node” in patients who previously had a prosthesis implanted for cosmetic reasons but then, over time, developed a carcinoma.

Silicone in lymph nodes appears in much the same way as “siliconomas”: in the form of small globules or masses of birefringent amorphous material, especially in the lymphatic sinuses, or as small intracytoplasmic vacuoles in histiocytes with micro-vacuolated cytoplasm (Figs. 14.5, 14.6, 14.7, and 14.8) that cause a granulomatous reaction within the lymph node. There also may be multinucleated giant cells. The size of the lymph node lesions may correspond to small foci that reflect the node’s trabecular architecture, without producing adenomegaly and which constitute only a histological finding. Alternatively, there may be extensive involvement, with most of the trabecular structure replaced. In the latter instance, there may be appreciable lymph node enlargement, occasionally, with rupture of the nodal capsule, infiltration of the peri-nodal adipose tissue, and a corresponding peri-nodal granulomatous reaction.

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig5_HTML.png — Fig. 14.5

Silicone in the axilla. A lymph node with deposits of silicone and micro-vacuolated histiocytes in the lymphatic sinuses (100× magnification)

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig6_HTML.png — Fig. 14.6

Silicone in the axilla. Dilated lymph node sinuses with silicone deposits and micro-vacuolated histiocytes (200× magnification)

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig7_HTML.png — Fig. 14.7

Silicone in the axilla. Silicone lumps and micro-vacuolated histiocytes in lymph nodes (450× magnification)

../images/465990_1_En_14_Chapter/465990_1_En_14_Fig8_HTML.png — Fig. 14.8

Silicone in the axilla. Silicone lumps in lymph nodes (450× magnification)

Axillary Lymphadenopathy Due to Silicones with Metastasis of Infiltrating Ductal Carcinoma

Below, we offer images of an axillary lymph node, post lymphadenectomy, in a patient with an infiltrating ductal carcinoma (NOS) and siliconomas in the breast. The first figures correspond to an area of the lymph node without metastasis, but with silicone lymphadenopathy: note the clear spaces of different diameter, representing lymphatic sinuses (Figs. 14.9, 14.10, 14.11, 14.12, and 14.13). The latter images, which are interesting because of the extreme rarity of this combination, show metastatic carcinomatous tubules infiltrating the silicone lymphadenopathy (Figs. 14.14, 14.15, 14.16, and 14.17). Here, we can see that the nodal parenchyma is infiltrated by well-differentiated carcinomatous tubules, with silicone clumps of different diameter between the carcinomatous tubules. To date, we have been unable to locate any similar images, of carcinoma infiltrating a siliconoma, in the literature.