A 58-year-old African American male with a history of oligometastatic colon cancer was evaluated in the GI clinic for asymptomatic abnormal liver function tests listed below. Two years prior to his assessment in the clinic, he underwent a right hemicolectomy for a colon mass seen on his index colonoscopy with surgical pathology revealing a moderately differentiated mucinous adenocarcinoma with negative margins and 3 out of 50 positive lymph nodes. He subsequently had a right segmental hepatectomy following biopsy confirmation of a single site of metastatic disease in segment 7. Given his oncologic history and sudden liver enzyme elevation, an MRI MRCP was performed and revealed a common bile duct dilation of 15 mm with tapering to 6 mm distally. In addition, there was a 23 by 13 per portal lymph node adjacent to the common bile duct without intraluminal masses or strictures identified. A follow-up PET CT was also concerning for multiple hypermetabolic foci in the periportal and mesenteric lymph nodes as well as the right liver. His EGD was revealing for a dilated duodenal papilla as well as a classic fisheye ampulla with mucin protruding from the orifice. Due to the abnormal findings on the EGD, an endoscopic ultrasound was further pursued. The EUS identified a porta hepatis mass and a dilated common bile duct with hypochoke material. The heterogeneous periportal mass was identified abutting the common bile duct measuring 40 by 20 mm. A total of 4 passes were made for cell block and cytology. The biopsies were immunoreactive to ACK20 and CDX2 and negative for ACK7. This immunohistological pattern is characteristic of biliary metastasis from colon cancer, confirming his metastatic mucinous adenocarcinoma from his primary colon cancer 2 years prior. Now with biopsy confirmation that his obstructive mucobilia was secondary to recurrent metastatic mucinous adenocarcinoma of the colon, an ERCP was then pursued. After a sphincterotomy, copious amounts of mucin and sludge were then removed. Following mucin clearance, a final cholangiogram showed a low-grade stenosis at the proximal common bile duct consistent with invasion by the periportal mass. Minimal resistance was noted with 15 mm balloon sweeps. A second non-obstructing lesion was noted in the origin of the right anterior hepatic duct. In order to facilitate drainage, a 10 by 40 fully covered metal stent was then placed. The patient was now diagnosed with recurrent metastatic mucinous colon cancer, with plans to restart chemotherapy as an outpatient. However, he presented 2 weeks later in the oncology clinic with jaundice, lethargy and weakness and a sudden re-rise of his elevated liver enzymes. The patient was sent to the hospital from clinic for further management as his condition continued to deteriorate. Following his readmission, repeat imaging obtained showed that the stent was in place with proximal dilation. After a goals of care discussion, a repeat ERCP was then pursued. After removal of the stent, copious amounts of mucin and sludge were again removed. After mucin clearance, a cholangioscopy was then performed and identified two capillary biliary tumors. Two thrombic masses were noted in the common bile duct in the right hepatic duct measuring four millimeters concerning for metastatic mucinous tumor by optical diagnosis. The second cholangioscopy is revealing for the other four millimeter mid common bile duct mass. These two areas in the common bile duct and right anterior hepatic duct were concerning for malignant involvement. Biopsies were obtained and revealing for columnar mucosa with high and low grade dysplasia. A longer 10 by 80 fully covered metal stent was then placed across the common bile duct to assist in drainage. Despite the longer 10 by 80 fully covered metal stent there continue to be copious amounts of mucin from this invading mucinous periportal mass. And we were left with a dilemma on what to do further. Concerned that this invasive periportal mass was the source of obstructive mucobilia. And since the patient was deemed a high surgical risk and percutaneous drain placement by IR was likely to be low yield, we decided to perform a biopsy we decided to perform an endoscopic ultrasound chemical ablation. We used two milliliters of 99% ethanol via a 22 gauge needle. After chemical ablation was performed no mucin was seen from the biliary stent. After the ultrasound guided chemical ablation the patient was sent home on five days of antibiotic. Follow-up MRI MRCP imaging showed a reduction in the size of the periportal mass as well as interval improvement in the size of the intra and extra hepatic ductal dilation. Few weeks the patient's liver enzymes normalized. He underwent Fulferi and Avastin treatment. A follow-up MRI MRCP confirmed resolution of both intra hepatic and extra hepatic ductal dilation with stable appearing portal cable and mesenteric lymph node he continues to remain asymptomatic with normal liver enzymes 16 months from his last biliary stent placement and EUS guided ethanol ablation. In conclusion, this novel durable endoscopic treatment for a mucinous biliary obstruction with EUS guided ethanol ablation and covered metal stent placement in a patient with biliary metastasis from colonic mucinous adenocarcinoma. Also, we report the first case to our knowledge of obstructive mucobilia due to metastatic mucinous colon cancer.

colon cancer

liver metastasis

common bile duct dilation

periportal lymph node enlargement

endoscopic retrograde cholangiopancreatography