Are pancreatic malignant tumors hypoechoic?

Yes. The typical echogenicity of the pancreas is hyperechoic to adjacent fat. A hypoechoic mass within the pancreas can be benign or malignant. If you have a hypoechoic mass in the pancreas at age 30, you should undergo an MRI or ct of the abdomen to evaluate it further unless by ultrasound it is obviously cystic.