Soft tissue sarcoma
characteristic feature- Recurrence,
recurrence, recurrence.
Reason for recurrence-
1. Technical 2. The way these tumour exists {false capsule, pseudopods of
tumour, infiltration of surrounding tissues}
Very different type of staging system
Grade is also included in classification- GTNM system of
classification.
Site specific
distribution:-
|
site
|
Percentage (%)
|
|
Head and neck
|
11
|
|
Trunk
|
10
|
|
Retroperitoneum+intraabdominal
|
14
|
|
Visceral
|
15
|
|
Upper extremities
|
15
|
|
Lower
extremities
|
35
|
Pattern of growth:-
·
Most grow in expansile manner
·
Flattening the normal tissues around them in
concentric manner to form compression and reactive zone::: pseudocapsule
·
Extension sprouting small tentacles perforating
the pseudocapsule
·
Small finger like extensions grow to form
clinical occult deposits at a variable distance from the parent lesions
·
Continued growth=> multinodular mass
configuration of large, high grade deeply situated sarcomas
·
“Barriers”
Skin:-
·
Angiosarcoma/ Lymphangiosarcoma
·
Kaposi’s sarcoma
·
Epitheloid sarcoma
·
Dermatofibrosarcoma protuberans (on trunk)
Angiosarcoma/ (Blood Lymph
vessels tumours)
·
Haemangiosarcoma
o
Elderly
o
Aggressive, arises in head and neck, breast,
liver
o
Specially affects the skin and superficial soft
tissues (most STS are deep)
o
Differentiation from haemangioma difficult
o
5 years survival rate <20%
·
Haemangio-pericytoma
o
Originates in blood vessels
o
Affects all ages
o
Develops in the tips (Glomus tumour)
o
Lower extremity/ pelvis
o
Commoner in females
o
5 year survival rate about 50%
·
Lymphangiosarcoma
o
Older patients
o
Aggressive
o
Arises in chronic lymphatic stasis( specially
post mastectomy)
o
5 year survival rate 10%
Dermatofibrosarcoma Protuberans
–
·
Rare
·
Develops in the skin of trunk/ extremities
·
Almost never metastasizes
·
10% poorly differentiated (high grade)
·
Survival related to tumour grade
Kaposi’s sarcoma-
·
Tissue of origin not clearly known
·
Older patients
·
Extremely indolent lesion
·
Lower extremity (Mediterranaen Jews)
·
The epidemic and aggressive variety is
associated with AIDS and in bantu tribes
Epitheloid Sarcoma:-
·
Rare and tissue of origin unkown, young adults.
·
Aggressive, typically appears on distal
extremities.
·
Amongst the most common tumours of the hand and
foot.
·
Spreads to non-contiguous areas of skin,
subcutaneous tissue, fat, draining lymph nodes and the bone [differentiates it from other STS]
·
5 year survival rate 30%
Head & Neck
·
Rhabdomyosarcoma
·
Angiosarcoma (elderly)
·
Osteogenic sarcoma (jaw)
Rhabdomyosarcoma:-
·
Tissue of origin: Striated muscle
·
In G-TNM staging all are grade – III
·
All types in any age group
·
Embroynal: [
teenagers, head and neck(70%), genitalia ]
·
Pleomorphic: [>30
years, rare, develops in extremities, highly anaplastic]
Distal
Extremity:-
·
Epithelial sarcoma
·
Synovial sarcoma
·
Clear cell sarcoma
·
Osteogenic sarcoma (femur)
Clear cell sarcoma:-
·
Rare & tissue of origin unknown
·
Now recognised as a form of malignant melanoma
·
Adults<40 years
·
Painless, firm, spherical masses on tendon
sheaths & aponeurotic structures of distal extremities, head and neck
·
5 year survival rate is about 50%
Extremities:
·
Liposarcomas
·
Malignant fibrous histocytoma
·
Tendosynovial sarcoma
·
Fibrosarcoma
Liposarcoma:-
·
Arises from fat tissue
·
15-18%
·
Middle aged and older men
·
Thigh, groin, buttocks, shoulder,
retroperitoneum
·
Does not arise from benign lipomas!!
·
5 year survival rate is 80% for low grade, 20%
for high grade liposarcomas
Fibrosarcomas:
·
Tissue of origin: fibrous tissue
·
Incidence 5-10%
·
Affects all age groups
·
Arises in mesenchymal tissue
·
Usually involves abdominal wall and extremities
·
90% well differentiated (desmoid)
Malignant Fibrous Histiocytoma (MFH):-
·
Tissue of origin – fibrous tissue and histiocyte
·
Incidence – 10 – 23%
·
Age>40 years
·
Most common STS in some series
·
Develops in extremities (specially legs), Retroperitoneum
Mesothelium/ Retroperitoneum/ Mesentery :-
·
Mesothelioma
·
Leiomyosarcoma
·
Liposarcoma
·
Malignant Fibrous Histiocytoma
Mesothelioma:-
·
Tissue of origin: Mesothelium
·
> 50 years
·
Asbestos exposure
·
Involves Pleura, Peritoneum
·
Highly lethal
·
5 year survival rate is <10%
Retroperitoneal
Sarcomas:-
·
Liposarcomas
·
Leiomyosarcoma
Gastrointestinal
tract:-
·
Gastrointestinal stromal tumours (GIST) do not
express markers of myogenic differentiation.
·
Similar to leiomyosarcomas but different IHC
staining
·
GIST do not stain for actin (leiomyosarcomas
do!)
·
GIST express SC 117 (c-lat protein)
·
Gastrointestinal autonomic nerve tumours (GANT)
exhibit neural differentiation
·
The pattern of recurrence is intra-abdominal
including liver metastasis
Leiomyoma Peritonealis
Disseminata (LPD)
·
Women in reproductive years
·
Asymptomatic, benign looking leiomyomas
scattered throughout the peritoneal cavity ranging from 1-10cm in size
·
Stimulated by estrogen
·
LPD causes occasional mechanical problems with
bowel or pain
·
No treatment except estrogen or anti-estrogen
drugs required
Chest wall:
·
Desmoids
·
Liposarcomas
·
Myogenic sarcomas
Neurofibrosarcoma [MPNST,
Schwannoma]:
·
Origin: nerve sheaths (thickening nerves,
without autonomic predilection)
·
Young and middle aged
·
Patients with von Recklinghausen’s disease (10%
develop sarcomatous changes in life)
·
Histologically resemble fibrosarcoma
·
Presents with superficial
variety: low grade, spreads extensively along nerve sheaths without
metastasizng, survival rate >90%
·
Penetrating variety: nodular growth, vascular
invasion/lung metastasis- 5 year survival <20%
Synovial sarcoma:
·
Originates from tenosynovial mesothelium
·
Young adults 2nd to 4th
decade
·
Hard masses near tendons and painful
·
Synovial and epitheloid sarcomas are the most common
tumours of hands, knee and feet
·
G-TNM stage: all are grade III
·
High rate of local recurrence
History-
·
30 yrs old male, low socioeconomic
·
Swelling over right thigh- 3 months
·
Patient initially noticed a 2*2 cm swelling in
the Rt thigh 2 years back; gradual increase in size
·
Not associated with pain, weakness in the Rt
lower limb, ulceration or any other swelling in the Rt groin.
·
H/O surgery for the swelling one and a half
years back; swelling recurred within 6 months of surgery.
·
Another surgery done 4 months back; recurrence
within a month of the surgery.
·
Since then the swelling has increased rapidly in
size
·
No H/O wt loss or loss of appetite
·
No H/O headaches, seizures, bone pains, cough,
hemoptysis, jaundice.
·
No H/O Tb/DM/ HTN or any other co-morbid condition
·
Family History – non contributory
·
Personal History – non contributory
Examination:
·
Vitals – stable
·
Performance status – 90% Karnofsky
·
Nutritional status – poor
·
Hydration status – adequate
·
Lt Lower Limb – within normal limit
·
Rt Lower limb – extended at hip and knee
·
Scar mark of previous surgery seen
·
No ulceration, no pigmentation
·
8*6 cm mass in the lateral aspect of the thigh
·
No local rise of temperature
·
Fixed to skin
·
Nontender, irregular surface and margins
·
Variegated consistency
·
Fixed to the underlying muscles
·
No neuro-vascular deficit in the Rt LL
·
No enlarged inguinal LN present
Limb examination (important point):-
·
Attitude of extension or external rotation
·
Movements of the hip
Investigation:-
·
Core biopsy – exact histopathology and grade of
tumour
·
FNAC – it does not tell about grade of tumour, not very
popular in soft tissue sarcoma.
