Definition
Bland, superficial myxoid lesion with prominent thin walled vessels
Alternate/Historical Names
Diagnostic Criteria
Predominantly involves dermis and subcutis
May involve skeletal muscle on face
Multilobulated, poorly circumscribed
Myxoid stroma
Alcian blue positive, hyaluronidase sensitive
May have acellular mucin pools
Scattered bland stellate and spindled cells
Occasional multinucleated cells
Pleomorphism, mitotic figures rare
Occasional intranuclear pseudoinclusions
Many thin-walled small blood vessels Frequent neutrophils Entrapped epithelial component in 20-30% of cases
Keratinous cyst
Thin strands of squamous epithelium
Basaloid buds
If multiple or involving external ear, suggest Carney complex
Richard L Kempson MD
Original posting/updates:: 5/2707, 2/5/10
Superficial angiomyxoma may be indistinguishable from the cutaneous lesions of the Carney complex Carney complex should be considered if superficial angiomyxoma is multiple or involves the external ear
Carney complex
Myxomas
Cutaneous
External ear
Heart
Breast myxoid fibroadenoma
Cutaneous melanocytic lesions
Endocrine hyperplasia and neoplasia
Pituitary
Thyroid
Adrenal cortex
Testis large cell calcifying Sertoli cell tumor
Psammomatous melanotic schwannoma
Supplemental studies
Immunohistology
CD34
100%
Smooth muscle actin
0-90%
Muscle specific actin
67%
S100
0-40%
Factor XIIIa
60%
Negative: keratin, desmin, GFAP, ER, PR
Differential Diagnosis
Superficial angiomyxoma may be located in the perineum and external genitalia and thus confused with the first four lesions below.
Superficial Angiomyxoma Aggressive Angiomyxoma
Usually <5 cm
Nearly always >5 cm
Superficial
Deep seated
Long thin walled vessels
Medium to large thick walled vessels
Desmin negative
Desmin positive
Stromal neutrophils
No stromal neutrophils
Superficial Angiomyxoma Superficial Myofibroblastoma
Mean age 20 years for perineal lesions
Most 40-70's
Long thin walled vessels
Inconspicuous vessels
Desmin, ER, PR negative
Desmin, ER, PR positive
S100 variable
S100 negative
Stromal neutrophils
No stromal neutrophils
Frequently multinodular
Single nodule
Frequently involves subcutis
Superficial
Paucicellular
Cellular areas
Focal Cutaneous Mucinosis
Superficial Angiomyxoma
Poorly circumscribed
Circumscribed
Few blood vessels
Prominent vascular component
Neutrophils uncommon
Neutrophils common
Epithelial component rare
Frequent epithelial component
Myxoid Neurofibroma
Superfical Angiomyxoma
Poorly circumscribed
Circumscribed
Uniformly S100 positive
S100 variable
Intralesional axons
No intralesoinal nerve
No epithelial component
May have epithelial component
Neurothekeoma
Superfical Angiomyxoma
Vessels not prominent
Prominent vessels
S100 negative
S100 variable
Neutrophils infrequent
Frequent neutrophils
No epithelial component
May have epithelial component
May contain nerve twigs
No intralesional nerve fibers
Frequent epithelioid component
Lacks epithelioid component
Superficial Acral Fibromyxoma Superficial Angiomyxoma
Neutrophils uncommon
Neutrophils common
Epithelial component rare
Frequent epithelial component
Prominent fibrous component mixed/alternating with moderately cellular myxoid areas
Predominant hypocellular myxoid component, frequently in pools
EMA variably positive
EMA negative
Clinical
Mean age 40 years
Female genital cases mean 20 year
Range birth to 82
Nearly even male:female incidence
Genital cases 13:4 female:male
Wide range of sites: trunk, limbs, head and neck and perineal
30% recurrence rate
No aggressive recurrences
No metastases
May be associated with Carney complex
Especially if multiple or involving external ear
Grading / Staging / Report
Grading and staging not applicable
The surgical pathology report should contain or address the following:
Location
Type of resection or biopsy
Histologic diagnosis
Managerial category Ib (Recurrences do occur but are not destructive; never metastasizes)
Size
Depth (dermis, subcutis, below fascia, body cavity)
Margins
Results of supplementary studies if performed
Relationship to other specimens from the same patient
Lists
Vulvovaginal stromal and spindled tumors
Soft tissue lesions that frequently are prominently myxoid
Bibliography
Kempson RL, Fletcher CDM, Evans HL, Henrickson MR, Sibley RS. Tumors of the Soft Tissues, Atlas of Tumor Pathology, AFIP Third Series, Fascicle 30, 2001
Fletcher CDM, Unni KK, Mertens F. Pathology and Genetics of Tumours of Soft Tissue and Bone, World Health Organization Classification of Tumours 2002
Weiss SW, Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors, 4th edition, 2001
Calonje E, Guerin D, McCormick D, Fletcher CD.Superficial angiomyxoma: clinicopathologic analysis of a series of distinctive but poorly recognized cutaneous tumors with tendency for recurrence. Am J Surg Pathol. 1999 Aug;23(8):910-7.
Fetsch JF, Laskin WB, Tavassoli FA. Superficial angiomyxoma (cutaneous myxoma): a clinicopathologic study of 17 cases arising in the genital region. Int J Gynecol Pathol. 1997 Oct;16(4):325-34.
Allen PW, Dymock RB, MacCormac LB. Superficial angiomyxomas with and without epithelial components. Report of 30 tumors in 28 patients. Am J Surg Pathol. 1988 Jul;12(7):519-30.
