Cartilage tumors Notes

NOTES NOTES CARTILAGE TUMORS GENERALLY, WHAT ARE THEY? PATHOLOGY & CAUSES ▪ Tumors arise from cartilage tissue ▪ Benign/malignant ▪ Typically located on bones COMPLICATIONS ▪ Movement limitation, bone fracture, metastasis DIAGNOSIS DIAGNOSTIC IMAGING ▪ X-ray ▪ CT scan ▪ MRI OTHER DIAGNOSTICS ▪ Biopsy SIGNS & SYMPTOMS ▪ Can be asymptomatic, enlarging mass, pain TREATMENT SURGERY ▪ Resection CHONDROSARCOMA osms.it/chondrosarcoma PATHOLOGY & CAUSES ▪ Rare bone tumor ▫ Endochondral ossification → malignant cartilage production in bones ▪ Can be primary/secondary, arises from pre-existing benign lesion such as osteochondroma, enchondroma, periosteal chondromas TYPES ▪ Conventional (central/medullary), clear cell, mesenchymal, myxoid, dedifferentiated, periosteal ( juxtacortical), synovial, extraskeletal ▪ Affects appendicular skeleton more than axial skeleton 616 OSMOSIS.ORG CAUSES ▪ Unknown RISK FACTORS ▪ Age > 50 ▪ History of Ollier disease, Maffucci syndrome, Wilms’ tumor, radiotherapy (rare) COMPLICATIONS ▪ Pathological bone fracture ▪ Metastasis ▫ Most commonly lungs, bones ▪ Neurovascular structure impingement ▫ Ischemia, venous thrombosis, pseudoaneurysm

Chapter 109 Cartilage Tumors SIGNS & SYMPTOMS ▪ Painful, progressively enlarging mass; localized swelling; limited range of motion; fatigue; weight loss ▪ Neurovascular involvement ▫ Numbness, weakness, skin discoloration, loss of pulse, claudication DIAGNOSIS Staging ▪ Based on grade, spread ▫ Intracompartmental, extracompartmental, systemic/regional metastasis DIAGNOSTIC IMAGING CT scan ▪ Matrix calcification, endosteal scalloping OTHER DIAGNOSTICS Fine needle/core biopsy ▪ Determines histologic grading ▫ Grade 1: moderately cellular; small, round chondrocyte nuclei; abundant hyaline cartilage matrix; absent mitosis ▫ Grade 2: ↑ cellularity; ↓ chondroid matrix; enlarged chondrocyte nuclei; scattered mitosis evidence ▫ Grade 3: ↑ ↑ cellularity, sparse/ absent chondroid matrix; nuclear pleomorphism; mitosis clearly present TREATMENT SURGERY ▪ Intralesional curettage + local phenolization/ cryotherapy → cementation/bone grafting ▪ Complete resection MRI ▪ T1: low–intermediate intensity mass ▪ T2: high intensity mass X-ray ▪ Lytic pattern: calcifications, endosteal scalloping Figure 109.1 An X-ray of an intramedullary lesion with features of a low-grade chondroid lesion, likely a chondrosarcoma. OSMOSIS.ORG 617

OSTEOCHONDROMA osms.it/osteochondroma PATHOLOGY & CAUSES ▪ Benign tumor; outgrowth of tubular bone growth plate ▫ Most common benign bone tumor ▫ Average onset age is 10 years ▫ Capped with hyaline cartilage ▫ Can be pedunculated (with stalk)/sessile (broad base without stalk) ▪ Most common localizations: knee (distal femur/proximal tibia), pelvis, scapula TYPES ▪ Single sporadic mass ▫ Exostosis ▪ Multiple tumors ▫ Condition known as multiple osteochondromatosis CAUSES ▪ Mutation of EXT1/EXT2 genes involved in heparan sulfate glycosaminoglycan synthesis → local glycosaminoglycan reduction → disruption of cartilage, normal skeletal growth ▪ Radiation-induced ▪ Idiopathic COMPLICATIONS ▪ Pathologic fracture, bone malformation, bursitis, malignant transformation (more common in multiple osteochondromatosis) ▪ Neurovascular structure impingement ▫ Ischemia, venous thrombosis, pseudoaneurysm 618 OSMOSIS.ORG Figure 109.2 The gross pathology of an osteochondroma. The surface of the tumor is composed of hyaline cartilage and the centre composed of cancellous bone. SIGNS & SYMPTOMS ▪ Slow-growing palpable mass, pain, impaired range of motion ▪ Neurovascular involvement ▫ Numbness, weakness, skin discoloration, loss of pulse, claudication DIAGNOSIS DIAGNOSTIC IMAGING ▪ Often found incidentally (e.g. radiographic exam performed for different reason) CT scan ▪ Evidence of bony lesion and calcification MRI ▪ Further characterizes tumor morphology, cartilage cap thickness (thick cap → suspect malignancy)

Chapter 109 Cartilage Tumors Ultrasound ▪ Identifies pseudoaneurysms, thrombosis, bursitis X-ray ▪ Dense bony spur TREATMENT SURGERY ▪ Excision ▫ Symptoms occur/malignant progression signs OTHER INTERVENTIONS Figure 109.3 An X-ray image of the knee demonstrating a tumor with a cortex continual with normal bone, a characteristic feature of an osteochondroma. ▪ Radiological follow-up ▫ Asymptomatic Figure 109.4 The histological appearance of an osteochondroma. There is a core of cancellous bone with an overlying cap of hyaline cartilage. OSMOSIS.ORG 619