Hypoechoic metastases in the liver typically originate from which source?

Hypoechoic metastases in the liver most commonly originate from lymphoma due to the nature of how lymphomatous cells spread. Lymphoma is a cancer that arises from the lymphatic system, which can lead to widespread dissemination throughout the body, including the liver. When lymphoma cells invade the liver, they typically create a hypoechoic appearance on ultrasound due to their less dense cellular makeup compared to the surrounding liver tissue.

Additionally, while other sources such as the pancreas, renal system, and primary liver cancer can also lead to metastatic involvement of the liver, they generally present with different echogenic characteristics. For instance, pancreatic neoplasms may present variably but often appear more heterogeneous from a cystic or solid perspective. Renal cell carcinoma can lead to more complex lesions including hypervascular appearances. These variances in lesion characteristics on imaging modalities highlight why lymphoma is specifically noted for its hypoechoic liver metastases.