Pathology Notes

Practice questions answers Bone tumors © Jun Wang, MD, PhD 1. C. Key diagnostic features of osteoid osteoma include small size, clear margin and benign bone formation. Aneurysmal bone cyst is composed of non-endothelial lined blood filling space. Osteoblastoma has microscopic features identical to osteoid osteoma , but it is different in clinical presentations, size, bone involved, etc. Osteomyelitis has inflammation and bone necrosis. Osteosarcomas are malignant tumor with bone production. Microscopically they are pleomorphic malignant cells. Radiologically they have destruction appearance. 2. D. Osteoblastoma has microscopic features identical to osteoid osteoma , but it is different in clinical presentations, size, bone involved, etc. Ewing sarcomas are composed of sheets of small cells with round nuclei. Giant cell tumors have numerous multinucleated cells. Metastatic cancers have epithelial components similar to primary tumors. Osteosarcomas are malignant tumo

Practice questions Bone tumors © Jun Wang, MD, PhD 1. A 19-year-old man presents with worsening pain of his upper tibia. The pain was worse at night. He was hit at the same location two month ago during a baseball game. Physical examination and laboratory tests were unremarkable. X-ray examination reveal a well-defined 0.8 cm intracortical radiolucent area in the anterior tibia. The lesion was resected. Microscopic examination reveals thin, often interconnected spicules of bone. No inflammatory cells nor bone necrosis are seen. What is the most likely diagnosis? A. Aneurysm bone cyst B. Osteoblastoma C. Osteoid osteoma D. Osteomyelitis E. Osteosarcoma 2. A 25-year-old female clerk presents with worsening pain of her lower back for 6 months. She tried aspirin but no relief was obtained. She has a history of left breast invasive ductal carcinoma at 3 years ago, and was treated with surgery and chemotherapy. She denies any history of trauma at her back. Physical exa