Contrast-enhanced power Doppler endosonography and pathological assessment of vascularization in advanced gastric carcinomas--a feasibility study.
OBJECTIVE
Besides representing angiogenesis markers, microvascular density (MVD) and vascular endothelial growth factor (VEGF) are two important tools for the assessment of prognosis in patients with gastric cancer. The aim of our study was to assess the Doppler parameters (resistivity and pulsatility indexes) and vascularity index (VI) calculated by contrast-enhanced power Doppler endoscopic ultrasound (CEPD-EUS) in correlation with the expression of intra-tumoral MVD and VEGF in patients with gastric cancer.


METHODS
The study included 20 consecutive patients with advanced gastric carcinoma, but without distant metastasis at initial assessment. All the patients were assessed by contrast-enhanced power Doppler endoscopic ultrasound (EUS) combined with pulsed Doppler examinations in the late venous phase. The vascularity index (VI) was calculated before and after injection of second generation microbubble contrast specific agent (SonoVue 2.4 mL), used as a Doppler signal enhancer. Moreover, pulsed Doppler parameters (resistivity and pulsatility indexes) were further calculated. The correlation between power Doppler parameters and pathological/molecular parameters (MVD assessed through immunohistochemistry with CD31 and CD34, as well as VEGF assessed through real-time PCR) was assessed. Kaplan-Meier survival analysis was used for the assessment of prognosis.


RESULTS
Significantly statistical correlations were found between post-contrast VI and CD34 (p=0.0226), VEGF (p=0.0231), VEGF-A (p=0.0464) and VEGF-B (p=0.0022) while pre-contrast VI was correlated only with CD34 expression. Pulsatility index and resistivity index were not correlated with MVD or VEGF expression. Survival analysis demonstrated that VEGF-A is an accurate parameter for survival rate (p=0.045), as compared to VEGF (p=0.085) and VEGF-B (p=0.230). We did not find any correlation between the survival rate and ultrasound parameters (RI, PI, pre-contrast VI or post-contrast VI).


CONCLUSIONS
Assessment of tumor vascularity using contrast-enhanced EUS, including analysis of spectral Doppler parameters is possible and feasible in gastric cancer patients. A correlation between measured EUS vascularity and pathological parameters of angiogenesis (MVD and VEGF expression) was found.
Department of Gastroenterology, Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy, Craiova, Romania. sevastita@gmail.com
Sevastiţa
S
Iordache
Maria-Monalisa
MM
Filip
Claudia-Valentina
CV
Georgescu
Cristina
C
Angelescu
Tudorel
T
Ciurea
Adrian
A
Săftoiu
D000328:Adult; D000368:Aged; D003287:Contrast Media; D019160:Endosonography; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000150:complications* / Q000000981:diagnostic imaging*; D010743:Phospholipids; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000150:complications* / Q000000981:diagnostic imaging*; D013459:Sulfur Hexafluoride
D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride