Leiomyosarcomas and leiomyomas express diffuse positivity for desmin
and smooth muscle actin in contrary to SFTs.
, CD117, DOG-1, bcl-2, [beta]-catenin, and ALK are negative.
intermediate filaments in all samples were found positive and brown.
The neoplastic cells are positive for S100 (d) and Melan A (h) but negative for pan- cytokeratin AE1/3 (c), desmin
(e), CD34 (f), and HMB45 (g).
Following immunohistochemistry, the neoplasm was diagnosed as leiomyosarcoma, positive for SMA, desmin
and vimentin, and negative for c-kit, CD34, S100 and NSE (Figures 4, 5 and 6).
IHC was positive for vimentin (Figure 1B) and desmin
(Figure 1C) antibodies and negative for cytokeratin (AE1/AE3), suggesting that the tumour was of muscular origin.
After washing with PBS the sections were blocked with rabbit serum for 30 min followed by incubation with primary antibodies against the desmin
antigen (1:200) at 4C overnight.
Cellular angiofibromas are consistently positive for vimentin with variable expression of CD34 and desmin
, and negative for smooth muscle actin (SMA) and S-100 (2, 6).
6,17] As reported in present study, two cases were non-reactive to CK, EMA, desmin
, SMA and positive for vimentin and S-100.
In addition, a minor population of tumour cells stained for desmin
The antibodies used were CK7, CK20, CKAE1/AE3, EMA , CEA , WT1, Inhibin, vimentin, calretinin, CD117, CD99, PLAP, CD30, OCT4, AFP, KI67, CD20, CD79a, CD3, CD5, LCA, CKHMW, CKLMW, Desmin
, Synaptophysin and chromogranin, from (DAKO, Denmark).
2 (1:100 Dickinson), EMA (1:750 Dako), LCA (1:300 Dako), S100 (1:4000 Dako), HMB 45 (1:500 Dako), Synaptophysin (1:80 Dakocytomation), Actin (1:2500 Dako), Desmin
(1:200 Dako) and Myoglobin (1:8000 Dakocytomation).