Myxoid melanoma: Immunohistochemical studies and a review of the literature

A malicious masquerader

“…The diagnosis tends to be made late in disease progression. The prognosis of 10 years’ survival is similar to that of other primary melanomas of matching Breslow thickness 2 …”

“…as a previously ‘undescribed histological pattern noted in metastatic lesions’, with only ‘four cases’ reported 1 . Since then, approximately 40 cases have been reported 2 …”

“…The myxoid appearance is due to the presence of acid mucopolysaccharides within the stroma, 2 with a minimum requirement of 15% per cross‐sectional area of stroma 1 . Myxoid MM stains negatively for epithelial mucin, and positively for connective‐tissue mucin 3 .…”

Myxoid Clear Cell Sarcoma

“…7,14 Therefore, myxoid malignant melanoma is now recognized as a morphologic variant of malignant melanoma, but could also be considered as a variant of spindle cell or desmoplastic melanoma because in most myxoid melanomas the tumor cells are primarily spindle or stellate shaped. 7 However, the tumor cells in our case were mostly oval or fusiform rather than spindle shaped. The presence of myxoid areas in melanocytic neoplasms is not unique to melanomas as it has been noted also in common nevi, 15 cellular blue nevi, 16 and Spitz nevi.…”

“…[4][5][6] Numerous subtypes of malignant melanoma have been reported, and myxoid malignant melanoma is now a well-recognized rare morphologic variant of malignant melanoma. 7 Clear cell sarcoma has been also described to occasionally show prominent myxoid stroma, 3 but a myxoid variant of clear cell sarcoma has not been well described. We report a case of clear cell sarcoma with prominent myxoid change.…”