[Right atrial metastasis as an initial clinical manifestation of adenocarcinoma of the colon].

We report the case of a young woman suffering from colonic mucinous adenocarcinoma with the unusual clinical presentation as a right atrial metastasis. The tumor was successfully resected, and after histopathological characterization, the primary lesion was searched for and discovered. The tumor had the clinical appearance and echocardiographic pattern of a pedunculated atrial myxoma. The aspects of echo-patterns useful for differential diagnosis are discussed.