cutaneous myxoma

Definition: A cutaneous myxoma, a.k.a. superficial angiomyxoma, consists of a multilobulated myxoid mass containing stellate or spindled fibroblasts with pools of mucin forming cleft-like spaces. There is often a proliferation of blood vessels and an inflammatory infiltrate.

Immunostaining is positive for vimentin, negative for cytokeratin and desmin, and variable for CD34, Factor VIIIa, SMA, MSA and S-100.

Clinically, it may present as solitary or multiple flesh-colored nodules on the face, trunk, or extremities. Local recurrence is common.

It may occur as part of the Carney complex , and is sometimes the first sign.

Differential diagnosis : cutaneous myxoid tumors

Myxoid or mucinous background change is a common finding in a wide variety of cutaneous tumors and other diseases.

Myxoid tumors often have overlapping features and may show significant heterogeneity from area to area within a given specimen and from individual case to case. As prognosis and treatment vary considerably between many of these entities, accurate diagnosis is essential.

Myxoid tumors include :
 superficial angiomyxoma (cutaneous myxoma ),
 superficial acral fibromyxoma (digital fibromyxoma ) ,
- dermal nerve sheath myxoma (conventional neurothekeoma ),
 myxoid dermatofibrosarcoma protuberans ,
 giant cell fibroblastoma ,
 low-grade fibromyxoid sarcoma ,
 myxofibrosarcoma ,
 myxoinflammatory fibroblastic sarcoma.

See also

 angiomyxoid tumors
 cutaneous tumors
 myxomas