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: Surgery
Single file pattern is seen in breast cancer type? 
Select and explain. 
A. Intraductal, B. Infiltrating lobular, C. Infiltrating ductular, D. All
B: Infiltrating lobular
Answer: B: Infiltrating lobular 
Explanation: Ans. is 'b' i.e. Infiltrating lobular "The hisological hallmark of lobular carcinomas is the pattern of single infiltrating tumor cells, often only one cell in width (in the form of a single file) or in loose clusters or sheets."