Relationships Between ADC Value of Nasopharyngeal Carcinoma Lesion and Pathological Indices

Abstract

Background and Purpose: To investigate the pathological mechanism of primary lesion’s ADC variation of NPC, we analyze the correlations between ADC value of patients with NPC and the cell density, microvessel density and nuclear proliferation index. Materials and Methods Patients with locally advanced NPC treated with intensity modulated radiation therapy between April 2010 and November 2011 were involved. MRI Conventional and DWI scans were performed at two time points: before therapy and during radiotherapy (just two weeks thereafter). The ADC values of the primary lesion were measured. Histological specimens were dealt with hematoxylin and eosin staining and immunohistochemical staining.The cell density, microvessel density and nuclear proliferation index values of the primary lesions were counted. Finally, the relationships between the ADC value before therapy, the ADC difference between the two time point and those pathology indices were analyzed by correlation analysis. Results: There is negative correlation between the ADC value difference and the cell density (r=-0.426，P=0.001), and positive correlation between the ADC value difference and microvessel density(r=0.429，P<0.001). However, there is not significant correlation between the ADC value difference and nuclear proliferation index(P=0.291). There are not significant correlations between the ADC values before therapy and the cell density, microvessel density and nuclear proliferation index values(P values were 0.896, 0.517, 0.201 respectively). Conclusion ADC variation of NPC may have correlation with the cell density and the microvessel density, which provide pathological mechanism for ADC value using to predict the prognosis of NPC received radiotherapy.