Transcript Soft Tissue Tumors Lucy H. Liu, M.D. Department of Pathology University of Illinois at Chicago e-mail: [email protected].

Soft Tissue Tumors
Lucy H. Liu, M.D.
Department of Pathology
University of Illinois at Chicago
e-mail: [email protected]
Soft Tissue Tumors
UIC College of Medicine
M2 Pathology Course, Lecture # 63
Tuesday, January 28, 2003
11:30 am
Soft Tissue Tumors
Lecture Goals:
1. Nomenclature & classification system of tumors
2. Differences between benign and malignant tumors
3. Clinical & morphologic features of common tumors
4. Approach to diagnosis of soft tissue tumors
Soft Tissue Tumor
Neoplastic
conditions arising in
extraskeletal mesodermal tissues
-- Fibrous tissue
-- Smooth muscle
-- Skeletal muscle
-- Adipose tissue
-- Blood & lymphatic vessels
-- Peripheral nerves - neuroectoderm
Soft Tissue Tumor
General principles for diagnosis:
 Location
-- Deep lesions tend to be malignant
-- Superficial lesions - benign
 Size
-- Larger tumors tend to be malignant
 Growth pattern
-- Rapidly growing - malignant
-- Infiltrating - malignant
 Metastasis
-- Malignant
Soft Tissue Tumors
Approach to Diagnosis
Histological morphology
Immunohistochemistry
Cytogenetic study
Molecular analysis
Ultrastructure
Soft Tissue Tumors
Immunohistochemistry
Cytokeratin
 Vimentin

Smooth muscle actin
 Desmin
 S-100
 CD 31
 CD 34
Soft Tissue Tumors
Cytogenetic Changes

t( 2:13) Alveolar rhabdomyosarcoma
 t( 11;22) Ewing’s sarcoma/PNET
 t( 11;22) Desmoplastic small round cell tumor
 t( 12;16) Myxoid liposarcoma
 t( 9;22) Myxoid chondrosarcoma
 t(12;22) Clear cell sarcoma
 t( X;18) Synovial sarcoma
Nodular Fasciitis
Benign reactive soft tissue lesion
 Probably secondary to trauma
 On forearm, trunk, back- well circumscribed
 Spindle cells ( fibroblasts & myofibroblasts)
in loose matrix -“fibroblasts in tissue culture”
 Rapid growth, frequent mitotic figures
 Self-limited, cured by excision
 Must differentiate from a sarcoma

Nodular Fasciitis
Fibromatosis
Fibroproliferative lesions
 Fibroblasts & Myofibroblasts
 Infiltrative growth pattern
 Tendency to recur
 Desmoid - Infiltrative masses
in abdominal, extra-abdominal
& intra-abdominal
 Palmar, plantar fibromatosis
 Surgical excision

Fibromatosis
Fibrosarcoma
 Malignant tumor of fibroblast origin
 In adults, in lower extremities,
upper extremities, trunk
 Spindle cells in a herringbone pattern
 Increased cellularity, high
nuclear-cytoplasmic ratios

Must exclude other tumors which
resemble fibrosarcoma
- Peripheral nerve sheath tumor
- Synovial sarcoma
Fibrosarcoma
Dermatofibroma
Benign
fibrous histiocytoma
Usually
in skin
Mixture
of fibroblasts,
myofibroblasts, histiocytes
Surgical excision
Dermatofibroma
Dermatofibrosarcoma
Protuberans (DFSP)
Fibrohistiocytic
tumor
 Intermediate malignant potential
 In skin & subcutis
 Spindle cells in storiform pattern
 Local recurrence
 CD 34
 Transformation to fibrosarcoma
 Surgical excision
Dermatofibrosarcoma Protuberans ( DFSP )
Malignant Fibrous
Histiocytoma
Malignant
soft tissue tumor with
histocytic differentiation
Most common type of soft-tissue sarcoma
Most frequently encountered sarcoma
post radiation therapy
In adults, in deep soft tissue
- extremities & retroperitoneum
Marked pleomorphism, spindle cells,
storiform, myxoid
MFH
Leiomyoma

Benign soft tissue tumor
 Arising
in subcutaneous tissue
or blood vessel wall
 Usually painful

Fascicles of regular smooth muscle cells
Leiomyoma
Leiomyosarcoma
Malignant soft tissue tumor
 Arising in extremities of blood
vessel wall
 Necrosis, hemorrhage
 Fascicles, nuclear atypia
 High mitotic activity

Leiomyosarcoma
Rhabdomyosarcoma
Malignant tumor of striated muscle
differentiation
 In children & young adults
 Several subtype
- Embryonal
- Alveolar
- Botryoid
- Pleomorphic

Embryonal
Rhabdomyosarcoma
Most common in children,
in head & neck
 Most common subtype
 Rhabdomyoblasts with
cytoplasmic cross-striation

Embryonal rhabdomyosarcoma
Botryoid
Rhabdomyosarcoma

Most common in hollow visceral
organs - genitourinary tract

Polypoid, grape-like tumor masses

Scattered malignant cells in myxoid
stroma
Botryoid rhabdomyosarcoma
Alveolar
Rhabdomyosarcoma

In extremities

Fibrous septa with loose clusters of
rounded cells in center
- alveolar pattern
Alveolar rhabdomyosarcoma
Pleomorphic
Rhabdomyosarcoma

In skeletal muscles of older
persons, in thigh

Marked pleomorphism

Irregularly arranged cells

Multinucleated giant cells
Pleomorphic Sarcoma
Lipoma
Benign, well-circumscribed tumor of
well-differentiated adipocytes
 In adult, upper back, neck, shoulder
 Usually subcutaneous, any site of
adipose tissue
 Most common type of benign soft
tissue tumor
 Resemble normal adipose tissue
 Subtypes:angiolipoma, spindle cell lipoma

Lipoma
Liposarcoma

Second most common sarcoma in adults
In deep compartments of extremities
& retroperitoneum
 Lipoblasts
 Several subtypes
- Well differentiated/atypical lipoma
- Myxoid / Round cell
- Pleomorphic

Liposarcoma
Hemangioma
Benign lesion
 Resemble normal blood vessels
 Congenital or non-congenital
 Most common in infants & children
 Head & neck, internal organs - liver

Angiosarcoma
Malignant vascular tumor
 Many locations: skin, soft tissue,
breast, live, spleen
 Irregular channels & atypical
endothelial cells
 CD31- endothelial cell marker

Angiosarcoma
Schwannoma

Benign tumor of neural differentiation
- Schwann cells
In association with large nerve trunks
 Head & neck, extremities
 Antoni A
-- Cellular area, palisaded nuclei
 Antoni B
-- Less cellular area, myxoid background
 S-100

Schwannoma
Synovial sarcoma

Malignant soft tissue tumor
Unknown origin- misnomer
 Arising in region of a joint
& other sites of deep soft tissue
 Multilobular

Biphasic pattern
- spindle cells
- epithelial - like cells
 t( X;18 )

Synovial sarcoma