Abstract
Friend leukemia integration site 1 (FLI-1) nuclear transcription factor has been proposed as a suitable tool in the differential diagnosis of small round cell sarcomas. It has also been described as a nuclear marker of endothelial differentiation. Expression of FLI-1 has been demonstrated in Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) and vascular neoplasms. In the present study, we describe 2 cases of metastatic melanoma with small round blue cell morphology that showed strong nuclear expression of FLI-1. Because of the small round blue cell morphology and negative immunohistochemical staining for pan-melanocytic cocktail (HMB45, anti MART1 and anti-tyrosinase) and SOX10 in both cases, FLI-1 immunostaining was requested as part of the tumors workup. Ultimately, both cases were established as being metastatic melanoma. Dermatopathologists should be aware that melanoma can be strongly positive for FLI-1 and not misinterpret these cases for ES/PNET or vascular lesions, especially when melanomas show unusual morphology.
Original language | English (US) |
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Pages (from-to) | 790-793 |
Number of pages | 4 |
Journal | Journal of cutaneous pathology |
Volume | 44 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2017 |
Keywords
- FLI-1
- melanoma
- small round blue cell tumors
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Histology
- Dermatology