Doppler tissue perfusion parameters in recognizing pancreatic malignant tumors.

ABSTRACT

BACKGROUND: Histopathology, radiological imaging methods with the administration of contrast agents are efficient to differentiate focal lesions of the pancreas. Invasiveness, contrast toxicity, and limited accessibility ameliorate their application. Noninvasive and contrast-agent-free method could improve diagnostics and accelerate treatment. AIMS: The aim of the study is to evaluate the diagnostic properties of ultrasound parameters of organ perfusion in the detection of malignant tumors of the pancreas. METHODS: Thirty-six patients with a focal lesion of the pancreas underwent endosonography with color flow imaging and biopsy for histological evaluation. Five patients were excluded because of the absence of the Doppler signal in pancreatic lesion. In the dynamic tissue perfusion measurement (DTPM) means of flow velocity (FV), resistive index, pulsatility index, and perfusion relief intensity (PR) were estimated. RESULTS: In the group with malignant tumors FV was significantly lower compared with the group with inflammatory changes. In receiver operating characteristic (ROC) analysis FV below the optimal cut-off point of 2.382 cm/s identified patients with malignant lesions with a sensitivity of 92% and specificity of 90%. In the group with malignant tumors significantly lower values of PR in all considered percentiles were observed. Based on the ROC analysis in the group with solid tumors, it was found that PR25 ≤ 0.057 allowed to recognize malignancies with a sensitivity of 100% and specificity of 80%, and in the groups with solid and cystic tumors with a sensitivity of 100% and specificity of 79%. CONCLUSIONS: FV and PR intensity derived from DTPM are reliable markers in recognition of pancreatic malignant masses.