This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Pancoast tumor is \nSelect and explain. \nA. Superior sulcus tumor, B. Inferior sulcus tumor, C. Median sulcus tumor, D. None of the above', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Superior sulcus tumor It is a tumor of the pulmonary apex typically found in conjunction with a smoking history. It is situated at the top end of either the right or left lung.Most Pancoast tumors are non-small cell cancers i.e. squamous cell carcinomas (SCCs) or adenocarcinomas.", 'role': 'assistant'}]