Pathology Notes

Bone tumors   Updated: 08/12/2022 © Jun Wang, MD, PhD General Most common type of bone tumors: Metastatic malignancies Majority of primary bone tumors are benign Diagnostic considerations History: Age, bone involved, site of bone involved Radiological studies for invasive features Morphology/immunohistochemistry Features suggestive of malignancy Radiology: Invasion, bone destruction Microscopic: Pleomorphism, necrosis, invasive growth Classifications Hematopoietic: Myeloma Lymphoma Bone forming Osteoid osteoma Osteoblastoma Osteosarcoma Cartilage forming Osteochondroma Chondroma Chondrosarcoma Chondroblastoma Chondromyxoid fibroma Unknown origin Giant cell tumor Aneurysmal bone cyst Ewing sarcoma Adamantinoma Notochordal: Chordoma Tumor of joints: Tenosynovial giant cell tumor Tumor like lesions of bone and joint Nonossifying fibroma Fibrous dysplasia Ganglion cyst Practice questions...

Practice questions answers Lymphoid neoplasms II © Jun Wang, MD, PhD 07/26/2018 1. D. Young adults present with cervical lymphadenopathy is highly suspicious for Hodgkin lymphoma . The microscopic features and immunohistochemistry profiles are typical for a classical Hodgkin lymphoma , nodular sclerosis type. Anaplastic large-cell lymphoma has markedly atypical tumor cells with horseshoe or donut-shape large cells that are positive for ALK and CD30. Diffuse large B cell lymphoma is positive for CD20. Follicular lymphoma is positive for CD10 and CD20, but negative for CD15 and CD30. Both follicular lymphoma and reactive lymphadenopathy do not have Reed-Sternber cells. 2. A. Hodgkin lymphoma is associated with EBV. HHV8 is associated with primary effuse lymphoma and Kaposi sarcoma. HIV post a risk factor for various lymphomas, but most likely would not be directly associated with Hodgkin lymphoma . HPV is associated with carcinomas, especially squamous cell carci...

Practice questions Lymphoid neoplasms II © Jun Wang, MD, PhD 07/26/2018 1. Use this case for the next two questions. A 31-year-old man presents with slowly enlarged right cervical mass for 4 months. He has night sweating for 2 months. He has a history of infectious mononucleosis 5 years ago. Physical examination reveal a 4 cm tender mass at his lower right anterolateral neck. No other lymphadenopathy is seen. His laboratory tests are unremarkable. Biopsy of the mass reveal a lesion with nodular appearance, separated by fibrous bands. These nodules are composed of a mixed inflammatory cell infiltrate of neutrophils, eosinophils, lymphocytes and plasma cells. Scattered larger binucleated cells with prominent nucleoli are seen. Per immunohistochemistry studies, these large cells are positive for CD15 and CD30, but negative for ALK, CD20 and CD45. What is the most likely diagnosis? A. Anaplastic large cell lymphoma B. Diffuse large B cell lymphoma C. Follicular lympho...

Practice questions answers Lymphoid neoplasms I © Jun Wang, MD, PhD 07/26/2018 1. C. Typical clinical presentation of Burkitt lymphoma . Pay attention to epidemiologic features. Genetic alteration for Burkitt lymphoma involves c-myc. Bcl2 is seen in follicular lymphoma ; BRAF in hairy cell leukemia ; cyclin D1 in mantle cell lymphoma ; EWS in Ewing sarcoma, a tumor seen in children, characterized by small blue cells that are positive for CD99, but negative for CD45 and other lymphocytic markers such as CD10, CD20. 2. A. Burkitt lymphoma is associated with EB virus. HHV 8 is associated with primary effusion lymphoma . HIV can be a factor of promoting Burkitt lymphoma , but in the group of immunodeficiency associated Burkitt lymphoma . This case is a typical endemic type Burkitt lymphoma . HPV is usually associated with carcinoma, especially squamous cell carcinoma. 3. A. Although diffuse large B cell lymphoma may have similar immunohistochemistry profile, the ce...

Practice questions Lymphoid neoplasms I © Jun Wang, MD, PhD 07/26/2018 1. Use this case for the next three questions. A 5-year-old boy from southeastern Asia presents with rapidly enlarging mass on his left lower face. Radiological examination reveals a tumor invading into left mandible with bone destruction. Biopsy reveals sheets of monotonous intermediated sized tumor cells with round nuclei and scant cytoplasm. Among these tumor cells are many larger cells with abundant cytoplasm containing darkly stained cell debris. Immunohistochemistry studies reveal these tumor cells are positive for CD10, CD20, but negative for CD3, CD5, CD99 and pan cytokeratin. Proliferative index by Ki67 is approximately 100%. What gene is most likely altered in these tumor cells? A.                 Bcl2 B.                  BRAF C. ...