Correlation of Minimum Apparent Diffusion Coefficient and Maximum Standardized Uptake Value of the Primary Tumor with Clinicopathologic Characteristics in Endometrial Cancer

Abstract

Objective:To explore the correlation of the primary tumor’s maximum standardized uptake value (SUVmax) and minimum apparent diffusion coefficient (ADCmin) with clinicopathologic features, and to determine their predictive power in endometrial cancer (EC).Methods:A total of 45 patients who had undergone staging surgery after a preoperative evaluation with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computerized tomography (PET/CT) and diffusion-weighted magnetic resonance imaging (DW-MRI) were included in a prospective case-series study with planned data collection. Multiple linear regression analysis was used to determine the correlations between the study variables.Results:The mean ADCmin and SUVmax values were determined as 0.72±0.22 and 16.54±8.73, respectively. A univariate analysis identified age, myometrial invasion (MI) and lymphovascular space involvement (LVSI) as the potential factors associated with ADCmin while it identified age, stage, tumor size, MI, LVSI and number of metastatic lymph nodes as the potential variables correlated to SUVmax. In multivariate analysis, on the other hand, MI was the only significant variable that correlated with ADCmin (p=0.007) and SUVmax (p=0.024). Deep MI was best predicted by an ADCmin cutoff value of ≤0.77 [93.7% sensitivity, 48.2% specificity, and 93.0% negative predictive value (NPV)] and SUVmax cutoff value of >20.5 (62.5% sensitivity, 86.2% specificity, and 81.0% NPV); however, the two diagnostic tests were not significantly different (p=0.266).Conclusion:Among clinicopathologic features, only MI was independently correlated with SUVmax and ADCmin. However, the routine use of 18F-FDG PET/CT or DW-MRI cannot be recommended at the moment due to less than ideal predictive performances of both parameters.

Utility of diffusion‐weighted imaging in association with pathologic upgrading in biopsy‐proven grade I endometrial cancer

“…In endometrial cancer, several studies have demonstrated that DWI is useful for evaluating the association between the apparent diffusion coefficient (ADC) of the tumor and the disease extent . Furthermore, an inverse relationship between tumor ADC and pathologic grade has been consistently reported . Of variable tumor ADC values, the minimum value on histogram analysis has been recently investigated in many studies and revealed promising results in associations with pathologic grade .…”