Serum oncofetal fibronectin (onfFN) mRNA in differentiated thyroid carcinoma (DTC): large overlap between disease-free and metastatic patients.

This study assessed if onfFN mRNA in the peripheral blood of patients with DTC can identify individuals with metastatic disease. Comparison of onfFN mRNA was made among 3 groups: disease-free, lymph node metastasis, and distant metastasis using real-time RT-PCR on 5 ml blood samples from each DTC patient. Fifty-one patients were included: 30 (59%) were disease-free; 7 (13.7%) had lymph node metastasis; and 14 (27.5%) had distant metastasis. OnfFN mRNA levels in the 3 groups were significantly different (P=0.001) but with a large overlap and the expression being highest in the disease-free group. Subgroup analysis of the metastatic groups did not show any effect of age, cell type, and serum TSH, Tg, and antiTg on onfFN mRNA. The within-run and between-run root mean square coefficients of variations were <2%. OnfFN mRNA in patients with DTC cannot identify those with metastatic disease.