This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
[{'content': 'All are considered to be poor prognostic factors in liver metastasis except \nSelect and explain. \nA. Synchronous lesions, B. Metachronous lesions, C. Extra-hepatic metastasis, D. CEA>200ng/ml', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Poor prognostic or factors affecting outcome Four or more tumors Extra hepatic disease Size >5cm Disease free interval <1 year Lymph node positive primary lesion CEA >200ng /ml Synchronous liver metastasis Ref:Sabiston 20th edition Pgno :1464-1465', 'role': 'assistant'}]