Topics

Chordoma

   Chordoma is a rare malignant bone tumor arising from embryonic notochordal remnants.    Most common primary malignant spinal tumor in adults

Limb Salvage and Amputation in Orthopedic Oncology: From Oncologic Safety to Functional Outcomes

Chondrosarcoma

3D Printed Implant Solutions in Pelvic Resections

Myths and Misconceptions

Evidence-based clarification of common myths in orthopaedic oncology, highlighting diagnostic pitfalls, biopsy planning, and surgical decision-making principles.

Basic Tumor Biology

Musculoskeletal tumours are diverse, historically classified by morphology and histology. WHO classification is the gold standard.

Soft Tissue Sarcomas

A diverse group of malignant tumours arising from mesenchymal tissues, commonly affecting extremities.

Multiple Myeloma

Multiple Myeloma is a malignant plasma cell disorder that causes bone marrow infiltration, excessive monoclonal protein production, and skeletal destruction through osteoclast activation and osteoblast suppression. It primarily affects older adults and commonly presents with bone pain, anaemia, renal dysfunction, and recurrent infections.

Ewing Sarcoma

Ewing sarcoma is a high-grade malignant small round cell tumor of bone and soft tissue, primarily affecting children and young adults. It represents the second most common primary malignant bone tumor after osteosarcoma. The hallmark of Ewing sarcoma is a chromosomal translocation involving the EWSR1 gene, most commonly t(11;22)(q24;q12), resulting in the EWSR1–FLI1 fusion gene.

Osteosarcoma

High-grade, malignant, osteoid-producing sarcoma of bone. Most common primary bone sarcoma. Arises predominantly in metaphysis of long bones (esp. around the knee).

Giant Cell Tumor (GCT)

GCBT is an aggressive benign bone tumour, classified as intermediate (locally aggressive) in the 2020 WHO classification. Accounts for 5–10% of all primary bone tumours.

Pigmented Villonodular Synovitis

Pigmented Villonodular Synovitis (PVNS), also known as tenosynovial giant cell tumor (diffuse type), is a benign but locally aggressive proliferative disorder of the synovium, tendon sheaths, and bursae. It is characterized by hemosiderin deposition, multinucleated giant cells, and synovial villous nodular overgrowth. Although histologically benign, PVNS can cause significant joint destruction if untreated.

Fibrous Dysplasia

Fibrous dysplasia (FD) is a benign bone disorder characterized by the replacement of normal bone with fibro-osseous tissue, leading to pain, deformity, and fractures. It results from post-zygotic GNAS gene mutations that disrupt osteoblastic differentiation. FD may be monostotic (single bone) or polyostotic, the latter often occurring as part of McCune–Albright syndrome (MAS). Radiologically, it presents with a ground-glass appearance and possible deformities such as the “shepherd’s crook” in the proximal femur. Treatment is primarily symptomatic, involving bisphosphonates for pain control and surgery for deformity or fracture correction. Although benign, the disease may progress during growth and stabilize in adulthood, requiring periodic follow-up for skeletal deformity and functional assessment.

Chondroblastoma

Chondroblastoma is a rare, epiphyseal, benign bone tumor that exhibits locally aggressive behavior. It primarily affects skeletally immature individuals, most commonly males in their second decade of life. Most frequent locations include the distal femur, proximal tibia, proximal humerus, and less commonly the hip or calcaneus.

Non-Ossifying Fibroma (NOF)

Aneurysmal Bone Cyst (ABC)

Unicameral Bone Cyst (UBC)

Unicameral bone cyst (UBC) is a benign, fluid-filled intramedullary lesion typically located in the metaphysis or diaphysis of long bones in children and adolescents. It is usually unilocular and adjacent to the cortex. Pathological fracture is the most common presentation.

Enchondroma

Overview • Enchondroma is a benign hyaline cartilage tumor, accounting for 20-25% of benign bone tumors. • It arises from residual cartilage cells that fail to undergo necrosis after physeal growth. • Can be solitary or multiple (Ollier’s disease, Maffucci syndrome).

What the Pathologist Needs

Osteochondroma

Benign hamartomatous cartilaginous lesions derived from aberrant cartilage through the perichondral ring that may be in the form of solitary or associated with genetic conditions like Multiple Hereditary Exostosis (MHE) · They grow and mature according to typical enchondral ossification and do not occur in bones formed through membranous ossification (skull)

Principles of Surgical Resection & Margins

Tumour resection aims to achieve oncologic control while preserving function; margin status is critical for local recurrence risk.

Staging Systems (Enneking, AJCC)

Biopsy Principles

Imaging Principles

Plain radiography remains the first-line and often diagnostic in most bone tumors, while CT provides detailed cortical and 3D anatomical evaluation. MRI offers superior soft-tissue and marrow contrast, essential for assessing intramedullary extension and surgical margins. PET/CT assist in detecting metastases and evaluating treatment response.

Soft Tissue Tumor Classification

The WHO introduced the classification of soft tissue and bone tumors (fifth edition) in 2020. The new WHO classification of soft tissue and bone tumors, introduced in 2020 (fifth edition), has made significant improvements in classification and introduced many new diagnoses.

Bone Tumor Classification

Overview of bone tumour classification systems and key characteristics that distinguish benign from malignant lesions.

Radiotherapy For Extremity Sarcomas

Metastatic Bone Disease

Metastatic bone disease (MBD) is the most common malignant condition of the skeleton, often originating from breast, prostate, lung, kidney, or thyroid cancers. Treatment targets fracture prevention, functional maintenance and pain relief.