This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Breast Cancer - Types and Staging, Subject name: Surgery
[{'content': "Which ca breast is B/L \nSelect and explain. \nA. Lobular, B. Paget's ds., C. Medullary, D. None", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is \'a\' ie. Lobular "LCIS (lobular Ca in situ) occurs bilaterally in 50 to 70% of cases, while DCIS occurs bilaterally in 10 to 20% of cases" - Schwartz"Invasive lobular Ca is frequently multifocal, multicentric and bilateral" - Schwartz', 'role': 'assistant'}]