18F-FDG-PET Can Predict Microvessel Density in Head and Neck Squamous Cell Carcinoma

Abstract

Aim: Positron emission tomography (PET) with ¹⁸F-fluordeoxyglucose (¹⁸F-FDG) plays an essential role in the staging and tumor monitoring of head and neck squamous cell carcinoma (HNSCC). Microvessel density (MVD) is one of the clinically important histopathological features in HNSCC. The purpose of this study was to analyze possible associations between ¹⁸F-FDG-PET findings and MVD parameters in HNSCC. Materials and Methods: Overall, 22 patients with a mean age of 55.2 ± 11.0 and with different HNSCC were acquired. In all cases, whole-body ¹⁸F-FDG-PET was performed. For each tumor, the maximum and mean standardized uptake values (SUV_max; SUV_mean) were determined. The MVD, including stained vessel area and total number of vessels, was estimated on CD105 stained specimens. All specimens were digitalized and analyzed by using ImageJ software 1.48v. Spearman's correlation coefficient (r) was used to analyze associations between investigated parameters. p-values of <0.05 were taken to indicate statistical significance. Results: SUV_max correlated with vessel area (r = 0.532, p = 0.011) and vessel count (r = 0.434, p = 0.043). Receiver operating characteristic analysis identified a threshold SUV_max of 15 to predict tumors with high MVD with a sensitivity of 72.7% and specificity of 81.8%, with an area under the curve of 82.6%. Conclusion: ⁸F-FDG-PET parameters correlate statistically significantly with MVD in HNSCC. SUV_max may be used for discrimination of tumors with high tumor-related MVD.

Keywords: head and neck neoplasms; neovascularization; pathologic; positron emission tomography.

Figure 1

(a) ¹⁸F-fluordeoxyglucose (¹⁸F-FDG)-PET/CT shows a metabolically active hypopharyngeal lesion. The acquired ¹⁸F-FDG-PET parameters of the lesion are as follows: maximum and mean standardized uptake values SUV_max = 22.07 and SUV_mean = 13.92. magnification: 200×. (b) Histopathological findings (CD 105 stained specimen). Vessel area is 1.2%, vessel count is 11.

Figure 2

The receiver operating characteristic (ROC) curve using SUV_max for distinguishing tumors with high microvessel density from lesions with low microvascularization. The optimal threshold SUV_max is 15, resulting in a sensitivity of 70.0% and a specificity of 75.0%. The area under the curve is 82.6%.