Metastasis of adenocarcinoma of the colon is commonly found in the lung, liver, or peritoneum. There are reports of tumors of the common bile duct (CBD) related to adenomas from Familial Adenomatous Polyposis and various organs metastasizing from outside of the gastrointestinal tract. We report a case of biliary colic due to metastatic adenocarcinoma of the colon to the CBD. A 57-year-old man with a history of metastatic rectosigmoid adenocarcinoma presented for evaluation of abdominal pain. He was diagnosed with rectosigmoid cancer in 2011 and had a lower anterior resection without chemotherapy or radiation. In 2013, he had local recurrence with metastasis to the liver. At that time he underwent several cycles of chemotherapy. At time of presentation, he was having pain associated with food intake for three weeks, which led to 30-pound weight loss. He had associated jaundice and was otherwise negative review of systems. On admission, liver function tests showed AST 115, ALT 51, alkaline phosphatase 714, and total bilirubin 2.0. Right upper quadrant ultrasound and showed gall bladder wall thickening with likely sludge and common bile duct 1cm. Computed Tomography of abdomen and pelvis showed probable pericholecystic sludge and a distended gallbladder as well as progression of liver metastasis. A pre-cholecystectomy endoscopic retrograde cholangiopancreatography (ERCP) revealed a main bile duct stricture and gallstones with sludge. A sphincterotomy was performed and stones were removed with retrieval balloon. Brush cytology and biopsies using cholangioscopy were obtained. Surgical pathology showed moderatelydiff erentiated adenocarcinoma consistent with colonic origin. One week later, a repeat ERCP was performed. Contrast was injected into the entire biliary tree, which showed a 4cm CBD stricture with proximal dilation. A 10mm, 6cm uncovered metal stent was placed. He was seen by oncology and resumed chemotherapy regimen. Usually, colon cancer metastasizes to the liver, which causes intrahepatic biliary tree obstruction and jaundice. Some patients have been identified to have extra-hepatic biliary obstruction caused by adenocarcinoma metastasis to lymph nodes adjacent to biliary structures. Obstructive jaundice with signs of acalculous cholecystitis on imaging in a patient with a history of colon cancer should raise suspicion for metastasis to CBD.Figure 1Figure 2