Application Of CT Perfusion And Correlation Between CT Perfusion Parameters And Microvessel Densities In Head And Neck Tumors

Objective1. Acquisition of all CT perfusion imaging parameters of the malignant andnonmalignant tumors in head and neck, normal muscle and normal thyroid gland,including blood flow (BF), blood volume (BV), mean transit time (MTT) andcapillary permeability surface area product (PS). To observe the appearance feature ofthe time-density curve(TDC); Testing whether significant differences exist in CTperfusion imaging corresponding parameters, between the malignant andnonmalignant tumors and the normal structure in head and neck.2. Testing whether significant discrepancies exist in microvessel density(MVD)and vascular endothelial growth factor(VEGF), between the malignant andnonmalignant tumors in head and neck. To analyze the relationship between the CTperfusion parameters (BF BV MTT and PS) and Microvessel Densities (MVD) in thehead and neck tumors.Materials and Methods1. CT perfusion was performed on 39 malignant tumors, 18 nonmalignanttumors and 30 normal muscle in head and neck with multi-slice spiral CT(MSCT).All data were sent to Advanced Workstation 4.1 and perfusion parameters (includingBF, BV, MTT, and PS) were obtained with GE PerfusionⅢsoftware; To test for thesignificance discrepancies in perfusion parameters between malignant tumors,nonmalignant tumors and normal muscle, by One-Way ANOVA, then continuedouble comparisons by Students-Newman-keuls (SNK); To test for the significanceof difference in perfusion parameters between the malignant lymph node andnonmalignant lymph node, as well as between malignant lymphoma and metastaticlymph node tumors by independent-samples t-test. 2. CT perfusion was performed on 7 thyroid cancer, 6 thyroid benign lesion and7 normal thyroid. All data were sent to Advanced Workstation 4.1 and perfusionparameters (including BF, BV, MTT, and PS) were obtained with GE PerfusionⅢsoftware; To test for the significance discrepancies in perfusion parameters betweenthyroid cancer, thyroid benign lesion and normal thyroid, by One-Way ANOVA, thencontinue double comparisons by SNK.3. MVD and VEGF was examined immunohistochemically using SP techniquesto 45 of the above-mentioned 70 malignant and nonmalignant tumors in head andneck, To test for the significance of difference in MVD and VEGF between themalignant and nonmalignant lesion by independent-samples t-test, and study thecorrelation of the perfusion parameters and MVD by Pearson correlation analysis.Results1. The CT perfusion imaging average blood flow of 39 malignant tumors in headand neck is (118.02±90.03) ml·min^-1·100g^-1, the average blood volume is (5.43±2.18)ml·100g^-1, the average mean transit time is (4.62±2.87)s, and the average capillarypermeability surface area product is (18.61±7.29) ml.min^-1. 100g^-1. The average bloodflow of 18 nonmalignant tumors in head and neck is (45.12±23.60) ml·min^-1·100g^-1,the average blood volume is (3.23±1.12) ml.100g^-1, the average mean transit time is(8.05±5.16)s, and the average capillary permeability surface area product is(14.56±4.58) ml.min^-1.100g^-1. All the perfusion parameters with malignant tumorsand nonmalignant tumors and normal muscle in head and neck has significantdifference(P＜0.05). The average blood flow of malignant tumors is higher thannonmalignant tumors and normal muscle, and the nonmalignant tumors is higher thannormal muscle. BF and BV with the malignant lymph node and nonmalignant lymphnode also has significant difference(P＜0.05). The average blood flow of malignantlymph node is higher than nonmalignant lymph node. BF, BV and PS of the malignant lymphoma is higher than the metastatic lymph node tumors, MTT is lowerthan the metastatic lymph node ,but there has no significant difference(P＞0.05).2. The CT perfusion imaging average BF of 7 thyroid cancer is (272.±106.68)ml·min^-1·100g^-1, the average BV is (11.18±2.80) 100g^-1, the average MTT is(3.50±1.60)s, and the average PS is (40.30±9.9) ml.min^-1.100g^-1. The average BFof 6 nonmalignant thyroid lesion is (176.51±98.88) ml·min^-1·100g^-1, the average BVis (9.89±4.97)ml.100g^-1, the average MTT is (5.07±2.14)s, and the average PS is(40.39±19.52) ml.min^-1.100g^-1. The average BF of 7 normal thyroid is(344.8±70.87) ml·min^-1·100g^-1, the average BV is (21.36±5.72) ml.100g^-1, the averageMTT is (4.15±1.22) s, and the average PS is (22.11±4.17) ml.min^-1.100g^-1. All theperfusion parameters with thyroid cancer and nonmalignant thyroid lesion has nosignificant difference(P＞0.05). The average BV of thyroid cancer and nonmalignantthyroid lesion is lower than normal thyroid(P＜0.05), and the average BF ofnonmalignant thyroid lesion is lower than normal thyroid(P＜0.05). The TDCappearance of thyroid cancer nonmalignant thyroid lesion and normal thyroid isdifferent.3. Mean value of MVD of malignant tumors in head and neck is (70.9±22.0)(strip) in 28 patients, and Mean value of VEGF is (3.43±0.79) (Mark). Mean valueof MVD of nonmalignant tumors in head and neck is (34.3±18.3) (strip) in 17 patients,and Mean value of VEGF is (1.35±1.36) (Mark). The MVD and VEGF with themalignant tumors and nonmalignant tumors in head and neck has significantdifference(P＜0.05). There was positive correlation between BF value,BV value andMVD, corresponding (r_BF=0.523 and r_BV=0.347, P＜0.05). MTT value of CTperfusion imaging has negative correlation to MVD of tumors(r=-0.527, P＜0.05).There also was positive correlation between VEGF and MVD (r_BF=0.690, P＜0.05).Conclusion 1. All the perfusion parameters with malignant tumors and nonmalignanttumors and normal muscle in head and neck except thyroid lesion has significantdifference. The average BF and BV of the malignant lymph node and nonmalignantlymph node also has significant difference. The average blood flow of malignantlymphoma is higher than the metastatic lymph node tumors, but there has nosignificant difference. The TDC appearance of thyroid cancer, nonmalignant thyroidlesion and normal thyroid is different. But the difference of the perfusion parametersamong them is not significant. CT perfusion imaging is valuable for qualitationdiagnose and definiting circumscription of the head and neck tumors.2. The MVD and VEGF with the malignant tumors and nonmalignant tumors inhead and neck has significant difference. There was positive correlation betweenVEGF and MVD. There also was correlation between the perfusion parameters andMVD. CT perfusion imaging can reflect vascularization inside the tumors,accordingly, CT perfusion imaging can help doctors to understand pathogeneticcondition overall, formulate best therapeutic regimen, and estimate prognosisexactitudly.