Most soft-tissue sarcomas present as masses that grow, becoming hard and painful (Fig. 26). Systemic effects include weight loss, pyrexia of unknown origin (PUO) and episodic hypoglycaemia, particularly with large retroperitoneal sarcomas.
Sarcomas may appear anywhere on the body: 60% occur in the extremities, 30% on the trunk (including retroperitoneum) and 10% on the head and neck.
Approximately 10–25% have metastases at presentation, most frequently in the lungs (Table 22).
Bone tumours
Most primary bone tumours present as painful swellings that may cause stiffness and effusions in nearby joints. Occasionally tumours present as pathological fractures. Systemic symptoms are uncommon except in Ewing’s sarcoma when PUO, weight loss and night sweats occur.
T
ABLE21 O
RIGINS OF PRIMARY BONE TUMOURSOrigin Benign Malignant
Cartilage (21%) Enchondroma Chondrosarcoma Osteochondroma
Chondroblastoma
Bone (19%) Osteoid osteoma Osteosarcoma Osteoblastoma
Unknown origin (10%) Giant-cell tumour Ewing’s sarcoma
Malignant fibrous histiocytoma
T
ABLE22 C
LINICAL FEATURES OF SOFT-
TISSUE SARCOMASTumour Fibrosarcoma
Liposarcoma
Embryonal rhabdomyosarcoma Alveolar
rhabdomyosarcoma Pleomorphic rhabdomyosarcoma Synovial sarcoma Angiosarcoma
Leiomyosarcoma
Age (years) 20 –50
40 – 60
0 –10
10 –20
40 –70
20 – 40 50 –70
45 – 65
Commonest sites Thigh, arm, head and neck
Thigh, head and neck (rarely arise from lipoma)
Head and neck, genitourinary (botryroid) Thigh
Thigh and upper arm
Leg
Skin and superficial soft tissues
Retroperitoneal and uterine
Primary therapy
Wide excision and adjuvant radiation
Wide excision and adjuvant radiation
Neoadjuvant chemoradiation and surgery
Neoadjuvant chemoradiation and surgery
Wide excision and adjuvant radiation
Wide excision and adjuvant radiation Wide excision and adjuvant radiation
Wide excision and adjuvant radiation
5-year survival (%) 90 (well differentiated), 50 (poorly differentiated) 66 (myxoid), 10 (pleomorphic) 40
60
10
40 15
40
Fig. 26 T1-weighted MRI scan showing large soft-tissue mass in medial compartment of left thigh due to soft-tissue sarcoma (arrows).
Osteosarcoma developing in pagetic bones may present with pain, swelling and warmth that progresses rapidly over weeks. The features of cartilage-derived bone tumours are shown in Table 23, of osteoid-derived bone tumours in Table 24 and of bone tumours of uncertain origin in Table 25.
Treatment
Soft-tissue sarcoma
• The optimal therapy for most soft-tissue sarcomas is surgical resection with an adequate margin of normal tissue.
• For extremity lesions, limb-sparing approaches are possible in most cases, and offer survival rates equivalent to amputation without the associated morbidity.
• For high-risk patients, local control is improved with
T
ABLE23 F
EATURES OF CARTILAGE-
DERIVED BONE TUMOURSAge (years) Site Location Radiograph
Notes
Enchondroma 10 –50 Hands, wrists Diaphysis
Well-defined lucency, thin sclerotic rim and calcification (Fig. 27) Ollier’s disease = multiple enchondromas
Osteochondroma (exostosis) 10–20
Knee, shoulder, pelvis Metaphysis
Eccentric protrusion from bone and calcification (Fig. 28)
1% transform to chondrosarcoma
Chondroblastoma 5 –20
Knee, shoulder, ribs Epiphysis prior to fusion Well-defined lucency, thin sclerotic rim and calcification
Chondrosarcoma 30 – 60
Knee, shoulder, pelvis Metaphysis or diaphysis Expansile lucency, sclerotic margin, cortical destruction and soft-tissue mass (Fig. 29)
T
ABLE24 F
EATURES OF OSTEOID-
DERIVED BONE TUMOURSAge (years) Site Location Radiograph
Osteoid osteoma 10 –30
Knee Diaphysis
Central lucency of <1 cm, surrounding bone sclerosis and periosteal reaction (Fig. 30)
Osteoblastoma 10 –20 Vertebra Metaphysis
Well-defined lucency, sclerotic rim, cortex preserved and calcification
Osteosarcoma 10 –25 and over 60 Knee, shoulder, pelvis Metaphysis
Lytic/sclerotic expansile lesion, wide transition zone, cortical destruction, soft-tissue mass, periosteal reaction and calcification (Fig. 31)
T
ABLE25 F
EATURES OF BONE TUMOURS OF UNCERTAIN ORIGINSAge (years) Site Location
Radiograph
Giant-cell tumour 20 – 40
Long bones, knee
Epiphysis and metaphysis post closure
Lucency with ill-defined endosteal margin, cortical destruction, soft-tissue mass and eccentric expansion (Fig. 32)
Ewing’s sarcoma 5 –15
Knee, shoulder, pelvis
Diaphysis and, less often, metaphysis
Ill-defined medullary destruction, small areas of new bone formation, periosteal reaction, soft-tissue expansion and bone/lung metastases (Fig. 33)
Malignant fibrous histiocytoma 10 –20 and over 60
Knee, pelvis, shoulder Metaphysis
Cortical destruction, periosteal reaction and soft-tissue mass
preoperative or postoperative radiotherapy. Local recurrence rates vary with the site; with extremity sarcomas only one-third recur. Recurrences nearly always occur within 3 years of initial presentation.
• Adjuvant chemotherapy improves disease-free survival but not overall survival.
• Isolated pulmonary metastases may be resected, with 20%
survival at 3 years; however, metastatic disease is generally relatively resistant to
chemotherapy.
Fig. 27 Enchondroma of middle phalanx showing a well-defined lucency and thin sclerotic rim with preserved cortex.
Fig. 28 Osteochondroma of distal femur showing a well-defined eccentric protrusion in continuity with bone cortex.
Fig. 29 Chondrosarcoma of distal femur showing expansile lesion with sclerotic margin, cortical destruction and punctate internal calcification.
Fig. 30 Osteoid osteoma of tibia showing eccentric dense bone expansion and central lucent nidus.
Bone tumours
• The clinical management of bone tumours requires a specialist multidisciplinary unit including orthopaedic surgeons, plastic surgeons and oncologists, and should be in the context of an adolescent oncology unit because the majority of patients are in this age group, with all their special needs.
• Neoadjuvant chemotherapy plays an important role in shrinking the tumour in localised osteosarcoma and Ewing’s sarcoma, hopefully enabling limb-sparing surgery without increasing relapse rates.
• Postoperative adjuvant
chemotherapy and radiotherapy are useful in some tumours.
Prognosis
See Table 26 for 5-year survival of sarcomas and bone tumours.
Fig. 31 Osteosarcoma of proximal femur showing sclerotic area with wide zone of transition, cortical destruction, soft-tissue mass, internal calcification and periosteal reaction with marked ‘sunray’ spiculation.
Fig. 32 Giant-cell tumour of metacarpal showing lucency with marked expansion, cortical destruction and soft-tissue mass. Internal cortical ridges produce a typical multilocular appearance.
Fig. 33 Ewing’s sarcoma of femur showing medullary destruction, lamellated periosteal reaction and soft-tissue extension.
FURTHER READING
Arndt C and Crist W. Medical progress:
common musculoskeletal tumors of childhood and adolescence. N. Engl. J.
Med. 1999; 341: 342–52.
Clark MA, Fisher C, Judson I and Thomas JM. Soft tissue sarcomas in adults. N. Engl. J. Med. 2005; 353: 701–11.