Expression of placenta growth factor: An independent factor for prediction of progression and prognosis of oral cancer

Background. Expression of placenta growth factor (PlGF) is found to correlate with the progression and prognosis of several human cancers. Methods. This study used an immunohistochemical technique to examine the expression of PlGF in 100 specimens of oral squamous cell carcinoma (OSCC). Results. We found that the higher mean PlGF labeling index was significantly associated with OSCCs with positive lymph node metastasis (p =.014) or with more advanced clinical stages (p =.016). Positive lymph node metastasis (p =.008) and PlGF labeling index >40% (p =.010) were identified as independent unfavorable prognosis factors by multivariate analyses with Cox regression model. Moreover, a Kaplan-Meier curve showed that OSCC patients with a PlGF labeling index >40% had a significantly poorer cumulative survival than those with a PlGF labeling index ≤40% (log-rank test, p =.003). Conclusions. The PlGF labeling index can predict the progression and prognosis of OSCCs in Taiwan.