Prognostic relevance of apparent diffusion coefficient obtained by diffusion-weighted MRI in pancreatic cancer

Diffusion-weighted magnetic resonance imaging (DW-MRI) is utilized as a method of oncologic imaging for predicting treatment outcomes. This study explored the role of DW-MRI in the treatment of patients with resected pancreatic cancer by comparing apparent diffusion coefficient (ADC) values with clinicopathological findings and survival rates.

Records of 54 patients in whom DW-MRI at 1.5T was performed (b values: 0 and 1000 mm(2) /s) before macroscopically curative resection were analyzed. ADC values were then calculated and compared with clinicopathological factors including age, gender, serum carcinoembryonic antigen levels, serum carbohydrate antigen 19-9 levels, lymph node metastasis, primary tumoral location, size, differentiation, resectability, and pT stage. A survival analysis of clinicopathological factors and ADC values was performed using the Kaplan-Meier method, and the results were evaluated with the log-rank test. Prognostic significance was assessed using the Cox proportional hazard model.

Significant associations were found between tumor differentiation and ADC values (P = 0.001). In a univariate analysis of overall survival, tumor differentiation (P = 0.037) and ADC values (P = 0.002) were identified as significant prognostic factors. However, age, gender, carcinoembryonic antigen levels, carbohydrate antigen 19-9 levels, lymph node metastasis, primary tumoral location, size, resectability, and pT stage were not associated with overall survival. In a multivariate analysis of overall survival, only ADC values were identified as significant prognostic factors (hazard ratio 2.293, 95% confidence interval 1.147-4.585, P = 0.019).

ADC values were found to be associated with prognosis in patients with resected pancreatic cancer.