Thyroid transcription factor-1 promotes lymph node metastasis by inducing lymphangiogenesis in ovarian carcinoma

Thyroid transcription factor-1 (TTF-1) expression is widely considered a specific marker for lung and thyroid carcinomas and plays an important role in angiogenesis in lung cancer. However, it can occasionally be expressed in other malignancies, including ovarian carcinomas, and the mechanism of TTF-1 in lymphatic metastasis of ovarian carcinomas is still unclear. This study aimed to define the TTF-1 expression and lymph vessel density (LVD) in ovarian carcinomas and look for their correlations with clinicopathological features.

We examined the incidence of thyroid transcription factor 1 expression (clone SPT24) and lymph vessel density (LVD) quantified through D2-40 by immunohistochemistry from 110 primary ovarian carcinomas and 40 benign ovarian tumor as controls in Chinese patients.

Thyroid transcription factor 1 was detected in 28 primary ovarian carcinomas (25.5%), which was significantly higher than its expression in benign ovarian tumor. TTF-1 expression was correlated with tumor FIGO stage,T stage and lymphatic metastasis. Moreover, LVD was associated with tumor FIGO stage, TNM stage. Furthermore, the LVD counts in group of TTF-1 positive expression were higher than in group of TTF-1 negative expression.

These findings indicated the occasional expression of TTF-1 immunoreactivity of ovarian carcinomas should be considered in the evaluation of neoplasms of unknown primary origin and TTF-1 might be involved in lymph node metastasis of ovarian carcinomas in the presence of lymphangiogenesis.