Paediatric Tumours

1. Paediatric Tumours Peter Calder Royal National Orthopaedic Hospital The London Intensive Paediatric Course

2. Definition Tumour �A swelling or lesion formed by abnormal growth of cells� A tumour can be�. Benign Malignant (Primary, secondary) Remember to score points�.

3. What do I need to know for the exam? Recognition Symptoms, signs, investigations� Staging Treatment Options

4. Natural History Mesenchymal neoplasms have characteristic patterns of behaviour and growth. Benign lesions are surrounded by a true capsule composed of compressed normal cells.

5. Natural History Spindle cell sarcomas form solid lesions with circumferential growth. The periphery of the lesion is composed of the least mature cells. (Round cell tumours) Enclosed by a pseudocapsule consisting of viable tumour cells and a fibrovascular reactive tissue with inflammatory tissue. This varies in thickness dependant on the lesion.

6. Behaviour Benign/latent Slow growth during normal growth of individual, then stop. Never become malignant. (Non-ossifying fibroma) Benign/active Progressive growth (Aneurysmal bone cyst) Benign/aggressive Locally aggressive but do not metastasize. There is a pseudocapsule with tumour extension into the reactive zone. Local control can only be achieved by complete removal of the lesion. (Giant-cell tumour)

7. Behaviour Malignant/Low-grade Low potential to metastasize. There is a pseudocapsule and tumour nodules exist within the reactive zone but rarely beyond. Local control by excision of normal cuff of tissue. (Parosteal osteosarcoma) Malignant/High-grade Rapid growth and early metastasis. Require local control and systemic therapy to prevent metastasis. (Osteosarcoma)

8. Spread Local anatomical barriers. Take the path of least resistance. Compression of normal tissue Resorption of bone by osteoclasts Direct destruction of local tissues Benign usually unicompartmental. Malignant are mostly bicompartmental. Dissemination almost exclusively through blood. (Early pulmonary involvement)

9. Staging Enneking et al Clin Orthop 1980;153:106-20 Enneking at al JBJS 1980;62(A)1027-30 Enneking WF Clin Orthop 1986;204:9-24

10. Staging � Grade (G) Assessment of biological aggressiveness G0 Histologically benign (well differentiated, low cell to matrix ratio) G1 Low grade malignant (few mitoses, moderate differentiation, local spread) G2 High grade malignancy (frequent mitoses, poorly differentiated with cellular atypia, necrosis, significant vascularity high risk of mets)

11. Staging � Site (T) Anatomic setting of the lesion T0 Intracapsular T1 Intracompartmental T2 Extracompartmental (spread beyond �fascial� plane without longitudinal containment)

12. Staging � Metastasis (M) Nodal or blood borne tumour spread M0 No evidence of regional or distant metastases M1 Regional or distant metastases evident

13. Clinical versus Viva

14. Age Predilection � Benign Birth � 5yrs Eosinophilic Granuloma Unicameral Bone Cyst (Rare) 6 � 18 yrs Unicameral (Simple) Bone Cyst Aneurysmal Bone Cyst Eosinophilic Granuloma Enchondroma (Olliers) Chondroblastoma Chondromyxoidfibroma Osteoblastoma Osteochondroma

15. Age Predilection � Malignant Birth � 5yrs Leukaemia Metastatic Neuroblastoma 6 � 18yrs Ewings Sarcoma (Round cell tumour) Osteosarcoma Parosteal Osteosarcoma

16. Anatomical Location

17. Soft Tissue versus Bone

18. Lump � Browse�s book Site Shape Size Surface Edge Consistence Tenderness Temperature Reducibility

19. Diagnostic Clues�.Soft Tissue Size A small mass (<5cm) is unlikely to be malignant. Accurate measurement with USS, CT or MRI. A rapid increase in size is more likely to be a sarcoma. A mass that increases and decreases in size is usually a cystic lesion.

20. Diagnostic Clues�.Soft tissue Site Superficial lesions are more likely to be benign. Superficial malignant lesions have a better prognosis than deep ones. Thigh and buttock regions are the commonest sites for soft tissue sarcomas, high index of suspicion.

21. Diagnostic Clues�.Soft tissue Consistency Lipomas are usually non tender and soft to palpation. May be firm if deep and muscles are contracted. Will seem to change when compartment relaxed. Soft tissue sarcomas tend to be firm and are not painful unless very large resulting in vascular compromise or neural compression.

22. Diagnostic Clues�.Soft tissue Cystic versus Solid Most cystic lesions are inflammatory or benign lesions, eg ganglion. If solid can be either benign OR malignant.

23. Diagnostic Clues�.Bone What is the effect of the lesion on the bone? High grade lesions spread rapidly destroying bone (describe as aggressive) Expansile

24. Diagnostic Clues�.Bone What is the response of the bone to the lesion? High grade lesions spread too rapidly for the bone to react. This results in a wide zone of transition. Low grade lesions spread slowly resulting in a narrow, sclerotic zone of transition.

25. Diagnostic clues�.Bone Features of malignancy Small is good, large is bad Cortical destruction Lack of sclerotic margin Presence of soft tissue mass Periosteal elevation

26. Diagnostic clues�.Bone Cartilage tumours have speckled calcification. Metaphyseal lesions Simple unicameral cysts are central Non ossifying fibromas are eccentric Expansile lesions ABC Simple bone cysts GCT � nearly always occur near the joint surface in mature bone. Chondroblastoma = GCT in children. Lytic tumour arising in the epiphysis.

27. Diagnostic clues�.Bone As tumour extends through the cortex the periosteum may be elevated Codmans triangle Spicules forming sunburst appearance

28. Diagnostic clues�.Bone Ewings sarcoma usually extensive lytic lesion. Perisoteal reaction � oinion skin

29. Remember Others�.

30. What do I do now? ? Transfer to Specialist Centre Advice Definitive Management �This is what they would do�.�

31. What do I do now? Full clinical examination. Bloods FBC, ESR, Biochemistry (Bone profile) Acid Phosphatase, TFTs, PSA, Protein electrophoresis (Myeloma) Urinalysis (Bence-Jones proteins) CXR Bone Scan MRI CT lesion and chest Angiography Biopsy

32. Biopsy Last step of staging. Performed by unit/surgeon who will perform definitive treatment. Biopsy tract/orientation is critical. Haemostasis to avoid tracking haemtoma. Open versus Needle

33. Surgical Margins Intra-lesional Marginal � through pseudocapsule Wide � cuff of normal tissue Radical � removal of entire compartment Amputation

34. Adjuvant Therapy Neo-adjuvant chemotherapy Radiotherapy

35. Summary Tumour Characteristics Age and Site Predilection Clinical Diagnosis Radiological Features Management Decision Making Treatment Headings