Malignant colorectal obstruction is a serious complication of advanced cancers. The obstruction can be caused by colorectal cancer, adjacent organ cancer or distant metastases. Rectal metastases from gastric cancer are rare. Foreign body ingestion is not a rare event and the majority of them causes no symptoms or complications. Nevertheless, they are likely to stop at any narrowing or angulation of the intestinal lumen. The authors describe a rare clinical presentation of an impacted foreign body in a pathological narrowing secondary to rectal metastasis of a gastric neoplasia that caused an acute malignant colonic obstruction. After endoscopic removal of the foreign body, there was complete resolution of symptoms avoiding surgery or palliative stenting. This case report highlights the need of careful inspection of colonic malignant strictures before stenting to exclude other causes of colonic obstructions, as an impacted foreign body.