Assessment of VEGF-D expression measured by immunohistochemical staining and F-18 FDG uptake on PET as biological prognostic factors for recurrence in patients with surgically resected lung adenocarcinoma

Objective To assess whether the combined evaluation of vascular endothelial growth factor D (VEGF-D) expression and fluorodeoxyglucose (FDG) uptake correlates with lymph node metastasis and post-operative recurrence in patients with lung adenocarcinoma. Methods Forty-six patients with lung adenocarcinomas, who had undergone both preoperative FDG PET imaging and thoracotomy, were enrolled in this study. The surgically resected tumor specimens were used to assess the protein levels of VEGF-D as measured by immunohistochemical assay. Results The patients were divided into the following four groups: those who were VEGF-D negative and had low FDG uptake (group I, 3 patients), VEGF-D positive and had low FDG uptake (group II, 20 patients), VEGF-D negative and had high FDG uptake (group III, 13 patients), and VEGF-D positive and had high FDG uptake (group IV, 10 patients). Lymph node metastases were seen only in group III. The 5-year disease-free survival rates were 66.7% in group I, 83.9% in group II, 8.3% in group III, and 64.0% in group IV (p < 0.0001). Thus, patients in group III exhibited the most unfavorable prognoses for recurrence. In multivariate analysis, the combined evaluation of VEGF-D expression and FDG uptake was an independent parameter for post-operative recurrence (p = 0.018). Conclusion A combination of low VEGF-D expression and high FDG uptake may be a biological indicator of lymph node metastasis and post-operative recurrence in patients with lung adenocarcinoma.