PTH-02-Disease of Soft Tisssue Flashcards
Diagnosis Main Point
Age, History, site, duration, pain, x-ray, CT, MRI, clinical-radiological-pathology
Common sites of primary cancers that metastasize to bone
Prostate, Breast, Thyroid, Kidney, Lung, GIT
Secondary tumor may radiologically be
osteoblastic (prostate, breast),
osteolytic (kidney, lung and melanoma )
mixed.
Common Cancer in Children
Neuroblastoma,
Nephroblastoma
Ewing’s sarcoma….etc
Sites involved by metastasis:
axial skeleton(vertebral column, pelvis, ribs, skull, sternum),
proximal femur
Humerus.
Primary Bone Tumors
Benign OR malignant
-Bone forming.
-Cartilage forming.
-Miscellaneous :fibrous, hematopoitic, multiple myeloma…. etc
Multiple myeloma is the most common in middle age
Osteosarcoma is the most common malignant tumor in children/ adolescents
Bone Forming Tumors
BENIGN 1- Osteoma : 2- Osteoid Osteoma/Osteoblastoma MALIGNANT 3- Osteosarcoma
Osteoma
Mainly affects frontal bones.
May affect all ages, mainly 40-50 years.
Asymptomatic, may produce pressure symptoms , or sinus obstruction.
Histologically: composed of mature bone.
May be left without treatment or removed
- Cause pressure symptoms.
- Cosmetic reason.
Osteoid Osteoma/Osteoblastoma
O.Osteoma in proximal femur <1.5- 2cm.
Age teenage & twenties, M:F is 2:1
Typical symptom : localized pain , worse at night, unrelieved by aspirin
X-ray: well defined cortical tumor with well defined radiolucent central nidus.
Simple OSTEOMA occurs in bones of skull
Histology: Trabeculae of woven bone surrounded by osteoblasts with central vascularized nidus.
Osteoid Osteoma vs Osteoblastoma
Osteoblastoma is similar, but more than 1.5-2cm. in size, more in axial skeleton
Slowly, progressing & increasing in size
AGGRESSIVE OSTEOBLASTOMA
Important to differentiate from Osteosarcoma
Osteosarcoma
Malignant mesenchymal neoplasm, in which the neoplastic cells produce OSTEOID
Most common malignant primary, non hematopoitic, bone tumor.
M>F, 75% < 20 years old
Majority in metaphyses of long bones, most around the knee
May be multiple in children with p53 mutation
Osteosarcoma-cause
Primary, arising de novo OR Secondary to an underlying bone disease e.g. Paget’s disease, radiation -Most are intramedullary→ cortex →peri- osteum → soft tissue -Rarely extends into joints -Location : --Classical ( Intramedullary) --Paraosteal (Juxtacortical) --Periosteal
Osteosarcoma-Pathogenesis
Genetic mutations: -RB gene mutation on chromosome 13 in 60-70% of sporadic cases -Inherited in familial retinoblastoma -Other mutations: p53, cyclins,CDK’s…etc Predisposing conditions
Osteosarcoma-Clinical Features
Enlarging mass, with or without pain.
Sometimes pathological fracture.
Hematogenous metastasis is common, mostly to the lungs.
X-ray: Ill-defined lesion, cortical destruction & extension to the marrow or soft tissue. ( Lytic/Sclerotic)
Codman’s triangle is a radiological term due to periosteal reaction with new bone formation.
Osteosarcoma-Pathology
Pleomorphic large malignant cells, prominent mitoses Lace like osteoid formed directly by malignant cells. Numerous osteoclasts may be seen Histological Variants : -Predominantly osseous. -Chondroblastic -Fibroblastic -Telengiectatic ………………. Others
Osteosarcoma-Treatment
Chemotherapy→ Assess amount of NECROSIS
Surgery
Radiation
Osteosarcoma-Prognosis
Aggressive tumor
The prognosis depends on the stage & variant of the tumor (conventional or other variants), location……etc
The grade is not as important as stage in osteosarcoma.
Primary Cartilage Forming Tumors
Benign -Osteosarcoma -chondroma Malignant -Chondrosarcoma Miscellaneous -Giant cell tumor(benign) -Ewing tumor(malignant)
Chondroma
Benign tumor composed of mature hyaline cartilage; 10% of primary bone tumor.
Intracortical (enchondroma) or extracortical.
Any age can be affected ( 20-40 y)
Small bones of hands and feet, solitary or multiple
Usually presents as asymptomatic bone swelling.
Chondroma & Enchondroma
Solitary benign.
Multiple→chondrosarcoma in 1/3
-Ollier’s disease: multiple enchondromas with endocrine abnormalities.
-Maffucci’s syndrome: Multiple chondromas with multiple hemangiomas.
Morphology : well circumscribed mass of mature cartilage
Osteochondroma (exostosis)
Single or inherited multiple
Arise from the metaphysis near growth plate of long tubular bones 1- 20cm
Majority around knee
Composed of outgrowth of cartilage cap overlying bone & bone marrow
May become ossified
Very rare malignant transformation
Chondrosarcoma
Malignant tumors of mesenchymal cells that produce cartilagenous matrix.
Older patients, 40-60y, M>F.
Site: central skeleton (pelvis,shoulder, ribs)
Primary (arise de novo), majority.
Secondary: multiple enchondromas or rarely osteochondromas.
Chondrosarcoma
Grossly: Glistening mass in the medullary cavity.
Histology: Chondroid cells with variable pleomorphism & binucleation. No osteoid.
Prognosis: depends on grade
Most are low grade, & recurrence
10% dedifferentiated & metastasize to lung ….etc
Fibrous Cortical Defect/ Non Ossifying Fibroma
Often symptomless
- Probably developmental, may mature
- Children
- Benign fibroblast proliferation
