Table 2 Histomorphological and immunohistochemical profile of SFTP
From: Determinants of outcome of solitary fibrous tumors of the pleura: an observational cohort study
|  | All (n = 42) | Malignant (n = 18) | Benign (n = 24) | p-value* |
|---|---|---|---|---|
Histomorphology | Â | Â | Â | Â |
Atypical localization | 2 (4.8) | 1 (5.6) | 1 (4.2) | ns |
Tumor size [cm] | 6.2 (4.8-14.1) | Â | Â | Â |
Tumor size > 10 cm | 19 (45.2) | 12 (66.7) | 7 (29.2) | 0.002 |
Sessile tumor | 11 (26.2) | 7 (38.9) | 4 (16.7) | ns |
Necrosis | 19 | 11 (61.1) | 7 (29.2) | 0.024 |
Nr of mitoses per 10 HPF | 4.1 (1.0-7.25) | Â | Â | Â |
> 10 mitoses per 10 HPF | 14 (33.3) | 13 (72.2) | 0 (0) | 0.022 |
Pleomorphism | 8 (19.0) | 6 (33.3) | 2 (8.3) | 0.03 |
Immunohistochemistry | Â | Â | Â | Â |
Ki-67 (proliferation rate)** | 5 (1–7) | 13.3 | 3.2 | 0.01 |
Ki-67 > 12%** | 3/27 (11.1) | 3 (30) | 0 | 0.02 |
Vimentin | 16/18 (88.9) | 8 (88.9) | 8 (88.9) | ns |
Cytokeratin | 1/19 (5.3) | 0 (0) | 1 (10.0) | ns |
Desmin | 4/16 (25.0) | 3 (33.3) | 1 (14.3) | ns |
SMA | 1/18 (5.6) | 1 (12.5) | 0 (0) | ns |
CD 34 | 35/36 (97.2) | 16 (94.1) | 19 (100) | ns |
CD 99 | 14/18 (77.8) | 5 (55.6) | 9 (100.0) | ns |
bcl-2 | 21/22 (95.5) | 8 (88.9) | 13 (100.0) | ns |
S-100 | 0/23 (0) | 0 (0) | 0 (0) | ns |