This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gynaecological oncology, Subject name: Gynaecology & Obstetrics
[{'content': 'Which of the following is not true regarding a krukenberg tumour \nSelect and explain. \nA. Has rough service, B. Usually bilateral, C. Shape of ovary is maintained, D. Primary is usually gastric carcinoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Krukenberg tumor is diagnosed only if it conforms to the following pattern ; Almost bilateral Smooth surfaces Freely mobile in pelvis It retains the shape of normal ovary. The tumors are secondary growth in the ovary and most often arise from a primary carcinoma of the stomach(70%). Histologically, the tumor has a cellular or myxomatous stroma amongst which are scattered large signet ring cells. Ref: Shaw Gynecology 17 e pg 464.', 'role': 'assistant'}]