Mr. Hameed et al., CAPSULAR SYNOVIAL-LIKE HYPERPLASIA AROUND MAMMARY IMPLANTS SIMILAR TODETRITIC SYNOVITIS - A MORPHOLOGIC AND IMMUNOHISTOCHEMICAL STUDY OF 15 CASES, The American journal of surgical pathology, 19(4), 1995, pp. 433-438
Formation of a fibrous envelope around the implant, a so-called capsul
e with resultant contracture of the prosthesis, is an occasional compl
ication of augmentation mammoplasty. The capsulectomy specimen contain
s mature scar tissue with mononuclear cells, histiocytes, and foreign
body giant cells. We studied 15 capsulectomy specimens. Seven showed a
striking form of papillary villous synovial-like hyperplasia similar
to detritic synovitis, a form of proliferative synovitis caused by ort
hopedic prosthetic devices. There was an accompanying infiltration of
the subcapsular surface by mononuclear cells, giant cells, and chronic
inflammatory cells. This reaction was independent of the type of pros
thetic device. In one case, foreign material consistent with polyureth
ane was demonstrated by histology and electron microscopy. Among eight
cases without capsular synovial-like hyperplasia (CSH), two showed de
nse fibrous tissue with foamy macrophages, and the rest showed fat nec
rosis, foreign body giant cell reaction, and occasional evidence of fo
reign material, including silicone granulomas. We stained four of the
CSH, two with silicone granulomas, and one sample with dense fibrous t
issue with peanut agglutinin and antibodies against vimentin and S-100
protein. Selected cases were also stained for concanavalin A and cyto
keratin. CSH stained for concanavalin A, peanut agglutinin, and viment
in but was negative for cytokeratin. Our cases showed a striking simil
arity in the staining pattern of CSH, detritic synovitis, and normal s
ynovium. We conclude that CSH of the mammary prosthetic capsule is pat
hophysiologically similar to proliferative synovitis.