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
[{'content': 'All of the following are histopathological findings of papillary carcinoma, except \nSelect and explain. \nA. Orphan Annie eye nuclei, B. Psammoma bodies, C. Monofocal papillary projections, D. Intranuclear grooves', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Pathology\n\nPapillary projections\nPsammoma bodies (concentric calcifications)\nPale empty (orphan annie) nuclei → FINELY DISPERSED CHROMATIN IMPARTS AN EMPTY APPEARANCE\n\n\nIntranuclear grooves and nuclear characteristics are diagnostic of papillary carcinoma\nMultifocality is common in papillary carcinoma\nTSH levels are high; tumors are TSH dependent, hence follow-up with TSH.\n\nKey Concept:\n\nMultifocality is common (up to 85% of cases) on microscopic examination.\nMultifocality is associated with an increased risk of cervical nodal metastases, rarely invade adjacent structures\xa0such as the trachea, esophagus, and RLNs.\n\nRLN implies lymph nodes.', 'role': 'assistant'}]