Preliminary Study On The Value Of Angiogenesis And Duel-phase Contrast-enhanced CT To Evaluate The Function Of Benign Pheochromocytoma

Pheochromocytoma is a rare neuroendocrine tumor arising from chromaffin cell.Most of pheochromocytomas can secrete and release the catecholamine and lead the dysfunction of body's circulation system and metabolic system,even causing the severe complications of the heart and brain.Therefore,it is a potential dangerous tumor.There is no unified criterion or effective predictor to evaluate the function of pheochromocytoma at present.Pheochromocytoma is rich in vascularity and many studies focus on how to discriminate the malignant from benign pheochromocytomas by assessing the tumors' angiogenesis.But what is related with the different benign tumors' various angiogensis need to be researched.CT is an important method to locate the pheochromocytomas.The enhancement pattern vary among pheochromocytomas at contrast-enhanced CT for different angiogenesis.So this study focus on the relationship among of the function,angiogenesis and CT enhancement pattern with the purpose of finding a predictor to evaluate the function of pheochromocytoma.Part I Preliminary Study on Benign Pheochromocytoma's Angiogenesis and FunctionObejective To study the relationship between the pheochromacytomas,MVD and VEGF expression which are two indexes of angiogenesis,and analyze the differences of MVD and VEGF expression in different groups of pheochromocytomas with the purpose of evaluating whether pheochromocytoma's function correlating with angiogensis.Methods From June 2009 to December 2015,thirty-one patients histologically diagnosed as benign pheochromocytoma were divided into two groups according to the length of preparing time before operation(group 1?2 weeks,group 2>2 weeks),and eight normal adrenal glands as the control group.The MVD and VEGF expression of all the pheochromocytomas and normal adrenal glands were evaluated,with the purpose of correlating the MVD and VEGF expression and analyzing the differences among two groups of pheochromocytomas and normal adrenal glands.The tumors' diameter,intratumoral necrosis and the patients' urine VMA were also analyzed with MVD and VEGF expression.Results ? The mean value of MVD in group 1 was 50.2±15.4 per HP,and less than that in group 2 with the mean value 69.5±3.8 per HP(p<0.05),but more than that in normal adrenal glands with the mean value 35.1 ±3.4 per HP(p<0.05).There were no difference of MVD mean value between groups divided according to tumors' diameter,intratumoral necrosis and the patients' urine VMA.? There was 30.8%high VEGF expression in group 1 less than that in group 2 with 77.8%(p<0.05),and there were no difference of high VEGF expression rate between groups divided according to tumors'diameter,intratumoral necrosis and the patients' urine VMA.? The MVD correlated with VEGF expression in pheochromocytomas(r=0.545,p<0.05).Conclusion ? The function of pheochromocytoma maybe correlate with the angiogenesis.? The angiogenesis of pheochromocytoma was more than that of the normal adrenal gland.? There were no correlation with the angiogenesis and tumor's diameter,intratumoral necrosis and the patients' urine VMA in this study.Part ? Study on the Correlation of Pheochromocytoma's Dual-Phase Contrast-Enhanced CT Patterns and Pheochromocytoma's AngiogenesisObejective To evaluate the dual-phase enhancement of pheochromocytoma with the modified CT parameters and explore the relationship between the pheochromocytoma's angiogenesis and CT parameters and signs.Methods Thirty-one patients with histologically diagnosed as pheochromocytoma underwent dual-phase contrast-enhanced CT.The two enhancement parameters of dynamic enhanced CT:the density difference before and after tissue enhancement and slope of the time-density curve were modified as the density difference before and after tissue dual-phase enhancement(?H)and enhanced velocity(V)which used as dual-phase contrast-enhanced CT parameters.The two modified parameters were calculated in all lesions.The differences of the ?H and V were analyzed between the VEGF high expression group and low expression group.Spearman's rank correlation was performed to determine the strength of relationship between MVD and enhancement parameters.The relationship between the angiogenesis(MVD and VEGF expression)and the enhanced phase and heterogeneity was also analyzed.Results ? The MVD correlated with the ?H H and V,and the Pearson correlation coefficents were 0.425 and 0.430(p<0.05).? According to the ?H in arterial or venous phase,the patients were divided into two groups.The MVD was more in arterial phase group(67.4±17.9 per HP)than that in venous phase group(51.9±15.4 per HP)(p<0.05).? The mean value of ?H and V were 60.3±19.9HU and 1.98±1.00HU/s in VEGF high expression group which were greater than those in VEGF low expression group with the mean value 42.4±18.2HU and 1.26±0.77HU/s(p<0.05).The VEGF expression correlated with the ?H and V,and the Pearson correlation coefficents were 0.465 and 0.387.? The high VEGF expression rate in arterial phase group were 57.9%and 58.3%in venous group with no difference between two groups.? According to heterogeneity of enhanced the patients were divided into two groups,There were no differences of MVD and VEGF expression between the two groups.Conclusion ? The two modified CT parameters:?H and V,can be effectively used to evaluate the early enhanced differences of various pheochromocytomas.?The MVD was important in the early enhancement of pheochromocytomas and the?H and V were related with the pheochromocytoma's angiogenesis.? The more pheochromocytoma's MVD the earlier great enhancement occured.? The enhancement heterogeneity may be related with vascular shape and location.Part ? The Value of Dual-phase Contrast-enhanced CT in the Preoperative Preparation of Adrenal PheochromocytomaObejective To study the difference of two parameters of dual-phase contrast-enhanced CT:?H and V between the two groups which divided according to the preoperation preparative time.To analyze the correlation of ?H and V and preparative time,and evaluate whether the value of ?H and V as predictors of the preoperative preparation of adrenal pheochromocytoma.Methods Thirty-one patients histologically diagnosed as benign pheochromocytoma were divided into two groups according to the length of preparing time before operation(group 1?2 weeks,group 2>2 weeks).The differences of ?H,V and the value of unenhanced CT between two groups were analyzed,and the correlation of?H and V and the length of preparing time also analyzed.According to the CT signs including the tumor diameter,heterogeneity and cystic degeneration the patients were divided different two groups.The ?H and V and the length of preparing time were all analyzed between these two groups.The relationship of urine VMA and ?H and V was also analyzed.Results ? The mean value of ?H and V in group 2 were 61.6±22.2HU and 2,1±1.0HU/s and more than that in group 1 with the mean value 40.6±11.7HU and 1.2±0.6HU/s(p<0.01).? The 95%confidence of ?H and V in group 1 were 33.6HU?47.7HU and 0.84HU/s?1.58HU/s and the 95%confidence of ?H and V in group 2 were 50.6HU?72.5HU and 1.56HU/s?2.58HU/s.? The ?H and V correlated with the length of preparing time(r=0.682 and 0.548).? The mean value of unenhanced CT in group 1 and group 2 were 36.2±8.5HU and 40.5±6.8HU,(P>0.05).There was no difference in the tumor diameter,heterogeneity and cystic degeneration between the two groups and there was no difference of ?H and V between these two groups divided according to these factors and urine VMA.? The mean diameter of the tumors with heterogeneity and cystic degeneration was more than those without them.Conclusions ? The ?H and V could be as predictors of the preoperative preparation of adrenal pheochromocytoma and may be used to evaluate the pheochromocytoma's function.? In this study,if the ?H or V was greater than 48HU or 1.58HU/s,more than two weeks of preparing time was advised.? All the pheochromocytomas'unenhanced value>10HU in this study,which could be as one of clues to diagnose the pheochromocytoma.? The bigger tumor,the more chance with heterogeneity and cystic degeneration.