Isolated sigmoid colon metastasis from lung micropapillary adenocarcinoma: a case report.

Lung cancer is a common malignant neoplasm that is prone to distant metastasis. Gastrointestinal metastasis from lung cancer is rather rare no matter what stage. Herein, we presented a case of pulmonary adenocarcinoma six months after thoracoscopic Lobectomy isolated metastasis to sigmoid colon. Then the patient underwent radical resection of metastatic tumors of sigmoid colon. The pathologic morphology and immunohistochemistry of lung adenocarcinoma is highly consistent with the sigmoid colon tumor and their gene profiles are likely similar expect for an AXIN1 mutation in primary tumor and not in the metastatic lesion.