The role of fibroblast growth factor 2 in patients with uterine smooth muscle tumors: an immunohistochemical study.

OBJECTIVE: Fibroblast growth factor 2 (FGF-2) is considered to be a potent stimulator of angiogenesis and seems therefore to play an important role in the growth of tumors. We compared the immunohistochemical profile of FGF-2 in patients with uterine leiomyomas, smooth muscle tumors of uncertain malignant potential (STUMP) and leiomyosarcoma (LMS). Furthermore, we tried to clarify the prognostic role of FGF-2 in uterine leiomyosarcoma.

STUDY DESIGN: FGF-2 expression was investigated by immunohistochemistry from paraffin-embedded tissue in 26 patients with leiomyoma, in 24 cases with STUMP and in 21 patients with LMS. The immunohistochemical profile of these 3 tumor entities was compared and regarding LMS correlated with different clinicopathologic parameters.

RESULTS: FGF-2 was expressed in 85% of leiomyomas, in 88% of STUMP and in 57% of LMS. Significant differences regarding the frequency of FGF-2 expression were observed between leiomyoma and LMS as well as between STUMP and LMS (p<0.05). In uterine LMS FGF-2 expression was statistically more frequent in cases with high histological grade (p<0.05). Furthermore, FGF-2 positive tumors demonstrated a statistically significant higher rate of recurrence disease and tumor progression (p=0.005). Disease free as well as overall survival was significantly shortened in patients with FGF-2 positive compared to FGF-2 negative tumors (p<0.05).

CONCLUSION: The significant correlation between FGF-2 expression and high histological grade indicates that FGF-2 might work as a negative predictive factor. Higher rates of recurrence disease as well as shortened disease free and overall survival among FGF-2 positive LMS support the potential role as prognosticator for poor clinical outcome.