CD34 negative superficial acral fibromyxoma: A rare case report

Superficial acral fibromyxoma (SAF) is a slow growing soft tissue tumor that mainly appears in the acral areas. Here, we report a case of a SAF with distinctive immunophenotype charachteristics. An 18-year-old female was referred to our clinic with the complaint of painless subungual nodule of great toe for a few months. The diagnosis of SAF was made according to histopathology and immunohistochemical (IHC) study, however, the IHC assessment showed positive staining with vimentin, focal reaction with smooth muscle actin, negative reaction with CD34, and positive staining pattern with CD99. These IHC findings are unusual for SAF. This reported case of SAF supports the fact that, although CD34 expression is characteristic for SAF, it is not always present.