Benign lesion (Nevi, pilomatrixoma, lipoma, dermoid, epidermoid cyst) Flashcards
Classification of soft tissue lesions?
Cystic vs Solid followed by tissue origin:
Solid:
- Epidermal/Adnexal
- peripheral nerve
- Fibrous tissue (fibroblastic, myofibroblastic, fibrohystiocytic)
- Smooth muscle
- Skeletal muscle
- Pericytic
- condro-osseous
- adipose
Common cystic soft tissue lesions?
Dermoid, epidermal, trichilemmal, synovial, ganglion.
Epidermal/Soft tissue solid lesions?
1) pyogenic granuloma
2) pilomatrixoma
3) verruca vulgaris
Peripheral nerve masses?
1) Fibrolipomatous hamartoma of nerve
2) Schwannoma
3) neurofibromas
4) neurothecoma
5) granular cell tumor
Fibrous tissue masses?
1) Nodularfasciitis
2) Fibrous hamartoma of infancy
3) Myofibroma
4) benign fibrous histiocytoma
5) Juvenile xanthogranuloma
Many others…
Smooth muscle masses?
1) Leiomyoma
2) angioleiomyoma
Skeletal muscle masses?
Rhabdomyoma
Pericytic (perivascular) masses?
Glomus tumor
Chondro-osseous masses?
Chondromas
Adipose tissue masses?
Lipoma
Lipoblastoma
General imaging of soft tissue masses?
Plain X-ray: for diagnosis of calcifying lesions or chondro-osseous lesions. Gives information on bony erosion/invasion.
U/S: Good for superficial lesions to differentiate solid vs cystic. Also good for vascular lesions with Doppler.
MRI: Gold standard for most soft tissue lesions. Gives best information on surrounding structures when planning resection.
CT: Rarely indicated.
Epidermal cysts management?
Respect due to risk of infection, contain ectodermal elements only.
Dermoid cysts management?
Contain dermal and ectodermal elements.
Should be removed as they will continue to increase in size. Angular Dermoids can be disfiguring if left.
Pilomatrixoma management?
Found in the head & neck, and upper extremity.
Case reports of malignancy
Resect electively
Nodular Fasciitis management?
Proliferation of fibroblasts/myofibroblasts- usually superficial but may occur in muscles.
Grow rapidly in the H&N, trunk, arms.
Excise electively- rarely recur
Fibrous hamartoma of infancy management?
Benign tumor occurs in the first 2 years of life, 1/4 congenital.
Occurs in shoulder, axilla, and upper arm.
Excise completely or risk local recurrence.
Myofibroma management?
Multi centric or generalized lesions present at birth- may affect organs but most commonly affect skin, bone. Generalized in often fatal.
Solitary - occurs later in childhood.
Multi centric and solitary grow through the first year and then regress.
Excision for form/function.
Lipoblastoma management?
Occurs as encapsulated lipoblastoma or lipoblastomatosis.
PLAG1 gene hybrid molecular testing for diagnosis.
Treat with excision. 1/5 reoccur due to incomplete excision - especially lipoblastomatosis which can grow between muscular planes.
Neurofibroma management?
Occurs as sporadic solitary lesions or multiple in NF-1
They are peripheral nerve sheath tumours.
Remove if symptomatic
Ganglion/synovial cysts?
Occurs near joint spaces
Ganglion most common in wrists - generally observe due to high recurrence
Synovial most common near knee
