Pathology Ch 26 Bones, Joints, and Soft Tissue Tumors Flashcards
What is the mineral that gives bone strength and hardness and is the storehouse for 99% of the body’s calcium, 85% of the body’s phosphorous, and 65% of the body’s sodium and magnesium?
Calcium Hydroxyapatite (TOPNOTCH)
Of all the proteins in the bone matrix, which one is unique to the bone?
Osteocalcin (TOPNOTCH)
Identify the bone cell: responsible for bone resorption
Osteoclast (TOPNOTCH)
Identify the bone cell: most numerous than any other bone forming cell
Osteocytes (TOPNOTCH)
Identify the bone cell: initiate the process of mineralization and express cell surface receptors that bind many hormones
Osteoblasts (TOPNOTCH)
What is the functional unit of bone?
Osteoblast and Osteoclast act in coordination and are considered the functional unit of bone known as the Basic Multicellular Unit (TOPNOTCH)
In what part of the bone can you see the histological abnormalities seen in achondroplasia?
Growth plate (TOPNOTCH)
Gross appearance: lack a medullary canal and the end of long bones are bulbous (Erlenmeyer Flask Deformity) and misshapen. The neural foramina are small and compress exiting nerves
Osteopetrosis (TOPNOTCH)
What is the main defect in Osteopetrosis?
Deficient Osteoblastic Activity (TOPNOTCH)
Osteoporosis cannot be reliably detected in plain radiographs until how much of the bone mass is lost?
30-40% (TOPNOTCH)
What is the histologic hallmark of Paget Disease of the bone?
Mosaic pattern of lamellar bone (Jigsaw pattern) (TOPNOTCH)
A variety of tumor and tumor like conditions develop in pagetic bone. However, what is the most dreaded complication of this condition?
Sarcoma (Osteosarcoma > Malignant Fibrous Histiocytoma, or chondrosarcoma) (TOPNOTCH)
80% of cases, what bone is involved in Paget DIsease?
Axial skeleton and proximal femur (TOPNOTCH)
What is the most common site of tuberculous osteomyelitis?
Spine (thoracic and lumbar) > knees and hips (TOPNOTCH)
Most cases of osteomyelitis reach the bone via what route?
Hematogenous (TOPNOTCH)
What do you call a small intraosseous abscess that frequently involves the cortex and is walled off by reactive bone?
Brodie abscess (TOPNOTCH)
What do you call the morphologic variant of osteomyelitis that typically develops in the jaw and is associated with extensive new bone formation that obscures much of the underlying osseous structures?
Sclerosing osteomyelitis of Garre (TOPNOTCH)
What do you call a dead piece of bone?
Sequestrum (TOPNOTCH)
Reactive woven or lamellar bone may be deposited and when it forms a sleeve of living tissue around a segment of devitalized bone, it is known as?
Involucrum (TOPNOTCH)
Morphology: Edematous granulation tissue containing numerous plasma cells and necrotic bone
Congenital Syphilitic Bone infection and Acquired syphillis (TOPNOTCH)
What is the most common primary malignant tumor of bone, exclusive of myeloma and lymphoma, and accounts for approximately 20% of primary bone cancers.
Osteosarcoma (TOPNOTCH)
What are the 3 conditions associated with the development of osteosarcoma?
- Paget disease
- Bone infarcts
- Prior irradiation (TOPNOTCH)
What part of the bone do osteosarcomas usually arise?
Metaphyseal region of the long bone of the extremities, 60% occur about the knee. (TOPNOTCH)
Morphology: Coarse, lacelike pattern of neoplastic bone produced by anaplastic malignant tumor cells
Osteosarcoma (TOPNOTCH)
Morphology: sheets of uniform small, round cells that are slightly larger than lymphocytes with small amounts of clear cytoplasm.
Ewing Sarcoma (TOPNOTCH)
Morphology: Presence of Homer Write rosettes ( tumor cells are arranged in a circle about a central fibrillary space)
Ewing Sarcoma (TOPNOTCH)
The diagnostic cell of embryonal, alveolar, and pleomorphic variants of Rhabdomyosarcoma which contains eccentric eosinophilic granular cytoplasm rich in thick and thin filaments
Rhabdomyoblast (TOPNOTCH)
Tadpole or strap cells are seen in what soft tissue tumor?
Rhabdomyosarcoma (TOPNOTCH)
Morphology: characterized by malignant spindle cells that have cigar shaped nuclei arranged in interweaving fascicles.
Leiomyosarcoma (TOPNOTCH)
Morphology: histological hallmark is the dual line of differentiation of tumor cells, epithelial like cells and spindle cells
Synovial Sarcoma (TOPNOTCH)
Gross morphology: unencapsulated, infiltrative, soft, fish flesh masses, often having areas of hemorrhage and necrosis
Fibrosarcoma (TOPNOTCH)
These cells mimic fetal fat cells and contain round clear cytoplasmic vacuoles of lipid that scallop the nucleus. Seen in liposarcoma.
Lipoblasts (TOPNOTCH)
Morphology: consist of mature white fat cells with no pleomorphism
Lipoma (TOPNOTCH)
Pathognomonic hallmark of gout
Tophi (TOPNOTCH)
What are the most common cutaneous lesions seen in RA?
Rheumatoid Nodules (TOPNOTCH)
The most important factors in the development of Osteoarthritis
Aging and mechanical effects (TOPNOTCH)
Bone eburnation and joint mice are seen in what disease entity?
Osteoarthritis (TOPNOTCH)
The most common cancers that metastasize to the bone are?
Prostate, breast, kidney, and lung (TOPNOTCH)
What bones are most commonly involved in skeletal metastasis?
In descending order: Axial skeleton ( vertebral column, pelvis, ribs, skull, and sternum), proximal femur, and humerus (TOPNOTCH)
Skeletal metastases are typically multifocal, however, what carcinomas that metastasize to the bone are notorious for producing solitary lesions?
Ca of Kidney and Thyroid (TOPNOTCH)
morphology: uniform oval mononuclear cells that have indistinct cell membranes and appear to grow in syncitium with scattered numerous osteoclast type giants cells having 100 or more nuclei that have identical features to those of the mononuclear cells
Giant cell Tumor (TOPNOTCH)
Morphology: trabeculae mimic chinese characters
Fibrous Dysplasia (TOPNOTCH)
Morphology: Storiform pattern or pinwheel pattern created by benign spindle cells with scattered osteoclast
Fibrous cortical defect and nonossifying fibroma (TOPNOTCH)
What is the primary characteristic of osteosarcoma?
The formation of bone by the tumor cells (TOPNOTCH)
The combined picture of increased bone cell activity, peritrabecular fibrosis, and cystic brown tumors is the hallmark of what disease of abnormal mineral homeostasis?
Hyperparathyroidism (Generalized osteitis fibrosa cystica or von Recklinghausen disease of the bone) (TOPNOTCH)
What is the xray pattern that is virtually diagnostic of hyperparathyroidism?
Subperiosteal resorption producing thinned cortices in the middle phalanges of the index and middle finger and loss of the lamina dura around the teeth (TOPNOTCH)
What is the most important prognostic feature of a bone sarcoma?
Histological grade (TOPNOTCH)
O ring sign is seen in what cartilage forming tumor?
Chondroma (TOPNOTCH)
Morphology: chicken wire pattern of mineralizaton
Chondroblastoma (TOPNOTCH)
Myositis ossificans is distinguised from the other fibroblastic proliferations by the presence of what structure?
Metaplastic bone (TOPNOTCH)
