Where does GIST most commonly metastasize?

Gastrointestinal stromal tumors (GISTs) are a type of tumor that typically arise from the interstitial cells of Cajal or precursor cells in the gastrointestinal tract. When considering the metastatic pattern of GISTs, they predominantly spread to the peritoneum, liver, and lungs.

The liver is a common site for metastasis due to the rich blood supply and proximity to the gastrointestinal tract, where GISTs originate. The peritoneum is also frequently involved because GISTs can disseminate seeding throughout the abdominal cavity, creating multiple metastatic implants. Additionally, while lung metastases are less common than liver and peritoneal involvement, they can still occur as GISTs advance.

The other options present various combinations of metastatic sites, but none match the frequency and clinical commonality associated with GIST metastases. Understanding these patterns is essential for predicting the behavior of the tumor and planning appropriate management strategies.