1. Soft Tissue Sarcomas
Group Members:
Agu, Hilary Hortelano, Yvonne
Castañeda, Marie Claire Pagalilauan, Rogeniv
Cometa, Fiona Rose Saguigit, Joshua
Eder, Richton Torida, Chinkee
Ganga, Swathy Tulauan, Kelvin

2. OVERVIEW
• Sarcomas
– heterogeneous group of tumors that arise
predominantly from the embryonic
mesoderm, but also can originate from the
ectoderm (eg. peripheral nervous system)
– can occur throughout the body and encompass
more than 50 subtypes with distinct histologic
lines of differentiation

3. iNCIDENCE
• Rare tumor
• <1% - in adults (estimated 10,000 cases per
year in the US)
• 7% - in children

4. Most common histologic
types in adults (excluding
Kaposi’s sarcoma)
Most common
in childhood

5. • Approximately two thirds originate in the
extremities (50 to 60%)
• Remaining one third:
• retroperitoneum
• Trunk
• Abdomen
• Head & neck

6. • Overall 5-year survival rate for patients with
all stages: 50 to 60%.
• Of the patients who die of sarcoma, most will
succumb to metastatic disease
• 80% of the time occurs within 2 to 3 years of
the initial diagnosis.

7. EPIDEMIOLOGY
• The dominant pattern of metastasis is
hematogenous, primarily to the lungs.
• Lymph node metastases are rare (<5%) except for
a few histologic subtypes such as:
epithelioid sarcoma,
rhabdomyosarcoma,
clear-cell sarcoma,
synovial sarcoma,
MFH,
angiosarcoma

8. RISK FACTORS
1. Radiation exposure
• External radiation therapy
• 8 – 50 fold increase in incidence: txt in
breast, cervix, ovary, testes and lymphatic system
2. Occupational chemicals
• Herbicides (phenoxyacetic acid), wood preservatives cont’g.
chlorophenols
• Thorium oxide, vinyl chloride, arsenic
- assoc. with hepatic angiosarcomas

9. RISK FACTORS
3. Trauma
• no causal relationship has been established
4. Chronic lymphedema
• Lymphangiosarcoma : has been reported as occurring after
filarial infections and in the lower extremities of patients
with congenital or heritable lymphedema.

10. GENETICS
Classification into two main groups:
1. with defined diagnostic
molecular events
• found to be younger with a
defined histology, suggesting a
clear line of differentiation.
• The defined molecular events
include:
– point mutations,
– a translocation causing
overexpression of an autocrine
growth factor ,or
– oncogenic fusion transcription
factor.
2. with variable histologic and
genetic changes.
• without currently identifiable
genetic changes or expression
profile signatures tend to occur in
older patients exhibiting
pleomorphic cytology and p53
dysfunction.

11. Oncogene Activation
• Oncogenes are genes that can induce malignant
transformation and tend to drive cells toward
proliferation.
• Several oncogenes have been identified in association
with soft tissue sarcomas
• MDM2
• N-myc
• c-erbB-2
• Members of the ras family

12. Tumor Suppressor Genes
• play a critical role in growth inhibition and can
suppress growth in cancer cells.
• Inactivation of tumor suppressor genes (also
known as anti-oncogenes) can occur through
hereditary or sporadic mechanisms.

13. Two genes that are most relevant to soft tissue tumors:
1. retinoblastoma (Rb) tumor suppressor gene
• Mutations or deletions in Rb can lead to development of
retinoblastoma or sarcomas of soft tissue and bone.
2. p53 tumor suppressor gene
• Mutations in the p53 tumor suppressor gene are the most
common mutations in human solid tumors
• have been reported in 30 to 60% of soft tissue sarcomas

14. INITIAL ASSESSMENT
Clinical Presentation
• asymptomatic mass – most common presentation
• Less common presentation of an extremity sarcoma may be a deep venous
thrombosis, particularly in patients without significant risk factors for thrombosis.
• Tumor size at presentation usually is associated with the location of the tumor.
– Smaller tumors generally are located in the distal extremities
– tumors in the proximal extremities and retroperitoneum can grow quite large before
becoming apparent.

15. Clinical Presentation
• often grow in a centrifugal fashion and compress surrounding normal
structures.
• Infrequently, their impingement on bone or neurovascular bundles
produces
• pain, edema, and swelling
• Retroperitoneal soft tissue sarcomas almost always present as large
asymptomatic masses.
• Less frequently, patients present with obstructive GI symptoms or
neurologic symptoms related to compression of lumbar or pelvic nerves.

16. Differential diagnosis
I. Benign lesions :
1. lipomas (100 times more common than sarcoma)
2. lymphangiomas
3. Leiomyomas
4. Neuromas
II. Other malignant lesions
1. Primary or metastatic carcinomas
2. Melanomas
3. Lymphomas
• Small lesions that have not changed for several years by clinical history may be closely
observed.
• All other tumors should be considered for biopsy to establish a definitive diagnosis.