Sarcoma Flashcards
Define satcoma
Malignant tumors from connective tissue cells (mesenchymal tumors)
Gen characteristics of sarcoma
Rare tumors in adults Types Soft tissue sarcoma: 80-84 osteosarcoma: 15-19 peak ages Ewing chondrosarcoma : 10-14 peak ages
Risk factors for sarcomas
Osteosarcoma:
hereditary retinoblastoma
Li fraumen syndrome
Ewing sarcoma:
Transcription of chromosome 22
Chrondrosarcoma:
IDH1&2 mutation in 50% of cases
Osteosarcoma gen description
Most common bone tumor
Pathoanatomy
- malignant spindle cells and osteoblasts
- central medullary tumor that invaded medulla itself w/ soft tissue and vascular invasion
Sites of metastasis
1) lung 2)bone
Sx
Tenderness at site
Infrequent pathological fracture
Dg X-ray of site determine pathology MRI for extent of invasion Lung CT for metastasis Isotope bone scan
Management of osteosarcoma
Pre op
- Trepine biopsy by Orthopedist
- careful to prevent contamination
Chemotherapy
- increases survival
- preop 2-3 cycles
- cisplatin/ high dose MTX
Surgery
- en block resection w/ clear margins
- Limb sparing
- endoprosthesis
Radiotherapy
-limited to palliative care as it’s kinda radio resistant
Outcome
- 60-70% survival 10-30% W/ metastasis
- 85% 5 year survival rate
Ewing’s sarcoma general characteristics
Pathoanatomy
Neural crest cells( rosette formation)
Affect diaphysis of long/flat bones
Invade medulla & cortex
Metastasis: lung, bone 25%
Sx
Painful swelling
Warm red tissue
Compression of abdominal organs and nerves
Dg
Plain X-ray: osteolytic lesion
MRI: local extent
CT: chest and abdomen
Management of Ewing’s sarcoma
Chemo therapy
6 cycles VIDE chemo: vincristine, ifosamide, doxorubicin, etoposide
8cycles of high dose therapy
Local tumor therapy
Surgery w/ limb salvage
Radiotherapy if excision margins are positive
Metastasis
Chemo+local therapy
Lung metastasis: chemo and lung irradiation
Bone: high dose chemo
Rx outcome
Local:55-64%
Metastatic10-20%
Lung only: 30%
Chondrosarcoma gen characteristics
2nd most common
Affects middle - late ages
Cartilage forming mg
Sx
Painful mass in pelvis/prox femur/ribs/humerus
Rx
Surgical resection/ limb conservation
Adjuvant chemotherapy isn’t proved to help
Radiotherapy after complete resection
Outcome
Grade1:90% Grade 3:40%
soft tissue sarcomas gen characteristic
Makes>females slightly
Children: rhabdomyosarcoma
Young adults: synovial carcinoma
Liposarcoma: young adults
Histological grading is crucial
Low grade:
Rare metastasis, slow growing, pseudo capsule, surgery only can cure
50%
High grade:
Local invasion, post surgical recurrence, hematogenous lung metastasis
50%
Signs and sx of soft tissue sarcoma
Painless enlarging soft tissue mass
Lower limb45%>upper limb15%>retroperitoneal
15%>head and neck10%
Dg Physical exam CXR CT Biopsy
surgical rx of soft tissue sarcoma
Intralesional/ intracapsional
- excision through tumour
- recurrence rate 100%
- no preOP dg& imaging
Marginal
- removed via pseudo capsule
- recurrence 20-70%
Wide
- wise margin of tissue removed w/ tumour
- works on low grade
- 30% recurrence for high grade
Radical
- en bloc resection of tumor & muscles
- low recurrence but loss of function
- up to 2cm uninvolved tissue resection limit
Chemo& radio therapy of soft tissue sarcoma
Chemo -most are chemo sensitive -doxorubicin -10-30% response rate Adjuvant chemo reduces recurrence not mortality
Radiotherapy
- mod radiotherapy
- useful in post op adjuvant therapy of high grade
What is GIST
Gastrointestinal stromal tumors
- most common sarcoma of GI
- 30% mg
- mutation of proto oncogene KIT
Rx is surgery
Metastasis of GIST doesn’t respond to surgery
What is KIT
KIT encodes for stem cell factor receptor
Expression detected by ICH CD117
Inhibited by IMATINIB
