3D dynamic contrast‐enhanced MRI of rectal carcinoma at 3T: Correlation with microvascular density and vascular endothelial growth factor markers of tumor angiogenesis

Abstract

Purpose:To determine how dynamic contrast-enhanced (DCE) MRI at 3T correlates with rectal carcinoma angiogenesis. Materials and Methods:Three-dimensional (3D) DCE MRI was performed in 38 patients (23 males, 15 females, mean age 60 years) with histologically-confirmed rectal carcinoma at 3T. Time-intensity curves (TICs) were used to measure peak enhancement ratio (ER peak ), time to peak enhancement (T peak ), first enhancement time (T first-enhance ), and uptake rate for rectal tumor, normal rectal wall, and gluteal muscle. After tumor resection, microvascular density (MVD) and vascular endothelial growth factor (VEGF) expression were determined using immunohistochemistry (IHC) stains on available specimens (N ϭ 24) to correlate with DCE MRI.Results: Rectal carcinoma showed higher ER peak (3.0 Ϯ 0.9 vs. 1.9 Ϯ 0.9, P Ͻ 0.001), higher uptake rate (2.8 Ϯ 1.5/ minute vs. 1.2 Ϯ 0.9/minute, P Ͻ 0.001), earlier T peak (88 Ϯ 56 seconds vs. 124 Ϯ 72 seconds, P ϭ 0.027), and earlier T first-enhance (34 Ϯ 6 seconds vs. 40 Ϯ 7 seconds, P ϭ 0.008) than normal rectal wall. Adenocarcinoma had shorter T peak compared to signet cell carcinoma (77 Ϯ 48 seconds vs. 160 Ϯ 62 seconds, P ϭ 0.004). T peak was negatively correlated with MVD (r ϭ -0.516, P ϭ 0.01) and the mean T peak was significantly earlier for the VEGF-positive group compared to the VEGF-negative group (57 Ϯ 17 seconds vs. 107 Ϯ 64 seconds, P ϭ 0.021).Conclusion: DCE MRI parameters help predict rectal tumor angiogenesis measured by MVD and VEGF expression and discriminate malignant from normal tissue.

DCE and DW MRI in monitoring response to androgen deprivation therapy in patients with prostate cancer: A feasibility study

“…There have been two prior studies on quantitative DCE MRI of prostate cancer before and after ADT (17,19), and one study investigating semiquantitative DCE MRI combined with MR spectroscopy (20), however none of these studies incorporated DW MRI. DCE MRI has been validated as a surrogate marker of tumor angiogenesis in prostate cancer and other primary tumors (21,22). In murine models, androgen ablation has been shown to suppress the production of the angiogenic factor VEGF (vascular endothelial growth factor) by the glandular epithelium and induce apoptosis of endothelial cells (23,24).…”

Value of diffusion-weighted imaging in the detection of viable tumour after neoadjuvant chemoradiation therapy in patients with locally advanced rectal cancer: comparison withT2weighted and PET/CT imaging

“…Between October 2008 and February 2009, 50 consecutive patients (39 men and 11 women; age range, 29-80 years; mean age, 56 years) who satisfied the following inclusion criteria were enrolled in this retrospective study: (1) patients with histopathologically proven locally advanced rectal cancer ($T3 or regional lymph node involvement) at imaging; (2) patients who underwent post-CRT 3.0 T rectal MRI with DWI and post-CRT 18 F-FDG-PET/CT, followed by surgery. Surgery consisted of low anterior resection (n544), Mile's operation (n53), Hartmann's operation (n51) or transanal endoscopic microsurgery (n52).…”

“…The usefulness of DWI at 1.5 T in measuring treatment response has been measured in several clinical studies [13][14][15]. Recently, 3.0 T MR scanners have become commercially available [16][17][18]; the increase in signal-to-noise ratio (SNR) provided by these machines offers increased DWI quality and improvements to apparent diffusion coefficient (ADC) maps.…”

Correlation of quantitative dynamic contrast‐enhanced MRI with microvascular density in necrotic, partial necrotic, and viable liver tumors in a rabbit model

“…Previous studies from other cancers have shown conflicting results 10 , 11 , 12 , 13 . In rectal cancer, Atkin et al (10) showed a negative correlation between ${\mathrm{normalK}}^{\text{trans}}$ values and MVD counts.…”