Soft tissue sarcoma


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Soft tissue sarcoma

  1. 1. Soft Tissue Sarcomas Dr.Arun Raj B DNB General Surgery MIMS
  2. 2. Introduction  Soft tissue sarcomas are rare and unusual neoplasms - about 1% of adult human cancers -15% of pediatric malignancies  Most commonly occur in the extremities(50%)  Also common in the abdominal cavity / retro- peritoneum, trunk/thoracic region, and head and neck
  3. 3. Definition  Sarcomas are malignant tumors that arise from skeletal and extra-skeletal connective tissue, mesenchymal cells including:  adipose tissue  bone  cartilage  smooth muscle including vascular smooth muscle  skeletal muscle
  4. 4. Etiology  H/o Radiation therapy .  Lymphedema – post surgery/ radiation/ filarial  Chemical exposure  Thorotrast, vinyl chloride, arsenic for hepatic angiosarcoma  Genetic syndromes  Neurofibromatosis – nerve sheath tumors  Li-fraumani syndrome  Familial gastrointestinal stromal tumor syndrome – KIT mutation
  5. 5. Classification  Soft tissue and bone  viscera (gastrointestinal, genitourinary, and gynecologic organs)  nonvisceral soft tissues (muscle, tendon, adipose, pleura, and connective tissue)  By differentiation (usually with IHC staining)  adipocytic tumors  fibroblastic/myofibroblastic tumors  fibrohistiocytic tumors  smooth muscle tumors  pericytic (perivascular) tumors  primitive neuroectodermal tumors (PNETs)  skeletal muscle tumors  vascular tumors  osseous tumors  tumors of uncertain differentiation
  6. 6. Age as factor  In childhood, embryonal rhabdomyosarcoma is most common  Synovial sarcoma is more likely to be seen in young adults (<35 years old)  An even distribution of liposarcoma and malignant fibrous histiocytoma as the predominant types in the older population
  7. 7.  Histopathology is determined by anatomic site  Common subtypes in the extremity are liposarcoma and malignant fibrous histiocytoma  In the retroperitoneal location liposarcoma and leiomyosarcoma are the most common histotypes  In the visceral location gastrointestinal stromal tumors are found almost exclusively
  8. 8. Histology  The biologic behavior of sarcomas is extremely variable  Histologic grade is a major prognostic determinant and is based on degree of mitosis, cellularity, presence of necrosis, differentiation, and stromal content  Low-grade sarcomas better-differentiated, less cellular, tend to resemble the tissue of origin to some extent, cytological abnormalities are less prominent, mitotic rate is low, Grow slower, low risk of metastasis.
  9. 9. Diagnosis  Extremity sarcomas usually present with as a painless mass  However, pain is noted at presentation in up to one third of patients  Delay in diagnosis is common, with the most common differential diagnosis for extremity and trunk lesions being a hematoma or a "pulled“ muscle  Physical examination - should include assessment of the size of the mass - its relationship to neurovascular and bony structures
  10. 10. INVESTIGATIONS  To obtain a tissue diagnosis  To determine the exact extent of the disease  To evaluvate metastatic disease
  11. 11. Biopsy  Core needle biopsy guided by palpation or by image guidance if not palpable  Excisional biopsy for superficial small lesions if needle biopsy non-diagnostic  Incision biopsy  Longitudinal incision without tissue flaps with meticulous hemostasis to prevent tumor seeding in hematomas AND NO DRAIN AND SUTURING  Send biopsy fresh and orientated
  12. 12. Imaging  MRI  For extremity masses  Gives good delineation between muscle, tumor and blood vessels  CT for abdominal and retroperitoneal  PET  May help determine high vs. low grade  May be helpful in recurrences
  13. 13. Metastatic Workup  Evaluation for sites of potential metastasis: - Lymph node metastases occur in less than 3% of adult soft tissue sarcoma. - For extremity lesions, the lung is the principal site for metastasis of high-grade lesions. - For visceral lesions, the liver is the principal site.  Low-grade lesions are assumed to have a low, <15% risk of subsequent metastasis  High-grade lesions have a high, >50% risk of subsequent metastasis
  14. 14. Workup  Low-grade extremity lesions require a chest radiograph  High-grade lesions require a chest CT  Visceral lesions should have the liver imaged as part of the initial abdominal CT or MRI.
  15. 15. Staging  Staging systems focus on: - Histologic grade of the tumor - Size of the primary tumor - Presence or absence of metastasis  Staging systems: - apply to risk of metastasis - disease-specific survival - overall survival - almost exclusively confined to extremity lesions
  16. 16. Staging  AJCC/UICC Staging System for Soft Tissue Sarcomas  T1: <5cm  T1a: superficial to muscular fascia  T1b: Deep to muscular fascia  T2: >5cm  T2a: superficial to muscular fascia  T2b: Deep to muscular fascia  N1: Regional nodal involvement  Grading  G1: Well-differentiated  G2: Moderately differentiated  G3: Poorly differentiated  G4: Undifferentiated
  17. 17. Staging Stage IA G1,2 T1a,b N0 M0 Stage IB G2 T2a,b N0 M0 Stage IIA G3,4 T1a,b N0 M0 Stage IIB G3,4 T2a N0 M0 Stage III G3,4 T2b N0 M0 Stage IV Any G Any T N1 M1 **Does not take into account extremity vs. visceral Staging system predicts survival and risk of metastasis, but not local recurrence
  18. 18. Prognostic Factors  Increase risk of local recurrence – Age > 50 – Recurrent disease – Positive surgical margins – Fibrosarcoma – MPNST  Increase risk of distant metastasis – Size > 5 cm – High grade – Deep location – Recurrent disease – Leiomyosarcoma
  19. 19. MANAGAMENT  Concept of three dimensional clearance  MULTIDISCIPLINARY APPROACH
  21. 21. NCI Trial 1975- 1981,Rosenberg et al 43 pts Amputation Vs Limb Salvage + RT At 9 yrs follow up Recurrence rate – 6 % Vs 19% DFS - 71% Vs 63% OS - 71% Vs 70% NIH Alert 1985 – “LSS as Standard of care”
  22. 22. Read the cross sectional imaging Plan your surgery preoperatively Magnitude of Resection Reconstruction Rehabilitation Revise the anatomy Plastic / Vascular/Ortho help as required Surgical Planning
  23. 23.  Three Dimensional clearance  Frozen Section control  Mark the bed for adjuvant RT  Orient the specimen  Gross the specimen Surgical Principles
  24. 24. Gross Pathology  Centripetal growth  Pseudocapsule Compressed tumor cells Fibrovascular zone (reactive inflammatory cells)
  25. 25. QUALITY OF MARGINS Barrier – Tissue that has resistance to tumor invasion Thin Barrier Membranous muscle fascia Adult periosteum Epineurium Vascular sheath Thin growth plate Thick Barrier Iliotibial band Sacral fascia Joint capsule Periosteum of infant / young child Thick growth plate
  26. 26. Thin Barrier – 2 cm Thick Barrier – 3 cm Growth Plate – 5 cm Normal Tissue Equivalent Aim – Normal tissue outside the barrier
  27. 27. CURATIVE RESECTION MARGINS Barrier +ve - Outside the barrier Barrier –ve – > 5 cm margin
  28. 28. Adjuvant Therapy Radiotherapy Brachy / EBRT Chemotherapy
  29. 29. Adjuvant radiotherapy  Small, low grade tumors < 5cm resected with 2 cm margins may not require radiation  Adjuvant radiation should be added to the surgical resection: - If the excision margin is close - If extra muscular involvement is present - If a local recurrence would result in the sacrifice of a major neurovascular bundle or amputation  Improves local control but not survival
  30. 30. Radiotherapy  Can be given as brachy-therapy or EBRT or intra- operative RT  Brachytherapy for high grade lesions  External-beam radiation therapy for large (>5 cm) high- or low-grade lesions  Intra-operative RT given in cases of retro-peritoneal sarcomas.  Can be given as pre-operative/ post-operative RT.  Pre-operative preferred in head and neck malignancy/ rest post-operative RT
  31. 31. Chemotherapy  Can improve local control, but not survival  Doxorubicin and ifosfamide have response rates of 20%  Use only in advanced disease  Combination with radiation or neoadjuvant therapy are controversial  Hyperthermic isolated limb perfusion may be used for palliation
  32. 32. Metastatic disease  Lung most common site of mets, but visceral often go to liver  Median survival from development of metastatic disease is 8-12 months  Resection of pulmonary mets can give 5 year survival of 32% if all mets can be removed  >3 mets is poor prognosticator
  33. 33.  Surgeon is an important prognostic factor  Good preop planning (no ontable surprises)  Resect , Reconstruct , Restore
  34. 34. Thank youThank you