Correlation between FDG PET/CT and the expression of Ki-67, MMP-2, micro-vessel density (MVD), and pathological grading in squamous cell carcinoma of the esophagus

e15556 Background: Variable uptake of 18FDG has been noticed in positron emission tomography (PET) studies of patients with esophageal squamous cell carcinoma (ESCC). The aim of the present study was to determine if 18F-FDG PET/CT standardized uptake value (SUV) could quantitatively reflect tumor proliferation, invasion and angiogenesis, and to reveal the relationship between SUV and pathological grading of ESCC. Methods: Preoperative PET scans were performed in 47 patients with histologically proven ESCC. 18FDG uptake was semiquantitatively measured by SUV.Tumour sections were HE stained to determine the pathological grading,and were stained by immunohistochemistry for proliferation marker (Ki67), invasion marker (MMP-2), and angiogenic marker (CD34). The correlations between FDG SUVmax and Ki67 expression, MMP-2 expression, corresponding MVD were statistically analysed respectively. Results: Among all the 47 cases,there were 13 well- differentiated squamous cell tumors, 16 moderately differentiated tumors and 18 poorly differentiated tumors,45 of 47 tumors revealed FDG. accumulation in primary tumor foci confirmed by subsequently histopathologically. The mean FDG SUVmax value was 12.504 ± 6.805. Average Ki-67 index was (7.837±29.798) %, average MMP-2 index was (71.551%±27.126) % and average MVD was (18.429±9.603) accordingly. The SUV and Ki-67 index, MMP-2 index were positively correlated (r=0.581,0.594), and it was not correlated with MVD(P>0.05). The mean SUV of well-differentiated, moderately differentiated and poorly differentiated tumors were 9.787±1.477, 12.313±0.479, 15.053±2.147 respectively, and a significant difference could be determined between them by statistical analysis(P=0.000). Conclusions: A significant positive correlation is demonstrated between FDG PET/CT SUV and Ki-67 index, MMP-2 index of the primary ESCC. SUV could reflect proliferation and invasion potential of tumor. However, there is no significant correlation between SUV and MVD, thus it could not reflect tumor angiogenesis in ESCC. To some extent, SUV could reflect pathologic grading of ESCC. No significant financial relationships to disclose.