Malignant biliary obstruction due to metastatic non-hepato-pancreato-biliary cancer

Table 3 Characteristics of malignant biliary obstruction caused by various primary malignancies

	Unique characteristics/diagnostic clues	Major causes of malignant biliary obstruction
Renal cell carcinoma	Enhancing lesion on imaging. Most pancreatic metastases resectable and associated with a good prognosis. Can arise up to 32 years after diagnosis of primary tumor	Pancreatic metastasis (biliary obstruction rare)
Lung cancer	Most reported in small cell lung cancer. Possible primary small cell biliary cancer	Pancreatic metastasis
Gastric cancer	Most cases present after surgery for Borrmann 3 antral lesions. Possible need for double stenting due to gastric outlet obstruction	Lymph nodes, liver metastasis, direct invasion
Colorectal cancer	Intraductal growth can mimic bile duct cancer	Liver metastasis, lymph nodes
Breast cancer	Most reported in invasive lobular carcinoma. Possible duodenal obstructionCan arise up to 32 years after diagnosis of primary tumor	Lymph nodes, pancreatic metastasis
Melanoma	Possible pancreato-biliary primary	Pancreatic metastasis
Lymphoma	More common in non-Hodgkin's lymphoma. Possible pancreato-biliary primary	Lymph nodes
Sarcoma	Possible pancreato-biliary primary	Pancreatic metastasis