Metastatic melanoma mimicking solitary fibrous tumor: report of two cases.
Malignant melanomas are known for their remarkable morphological variation and aberrant immunophenotype with loss of lineage-specific markers, especially in recurrences and metastases. Hot spot mutations in BRAF, NRAS, GNAQ, and GNA11 and mutations in KIT are oncogenic events in melanomas. Therefore, genotyping can be a useful ancillary diagnostic tool. We present one case each of recurrent and metastatic melanoma, both showing histological and immunohistochemical features of solitary fibrous tumor (SFT). Mutational analysis detected BRAF and NRAS mutations in the primary and secondary lesions, respectively. This result confirmed the diagnosis of recurrent/metastastic melanoma.
Department of Pathology, Radboud University Medical Centre, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands, e.bekers@pathol.umcn.nl.
Elise M
EM
Bekers
Adriana C H
AC
van Engen-van Grunsven
Patricia J T A
PJ
Groenen
Harm
H
Westdorp
Rutger H T
RH
Koornstra
Johannes J
JJ
Bonenkamp
Uta
U
Flucke
Willeke A M
WA
Blokx
D000328:Adult; D000368:Aged; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005260:Female; D020558:GTP Phosphohydrolases / Q000235:genetics; D006801:Humans; D008545:Melanoma / Q000175:diagnosis* / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D012878:Skin Neoplasms; D054364:Solitary Fibrous Tumors / Q000175:diagnosis* / Q000235:genetics; D000096142:Cutaneous Malignant Melanoma
D008565:Membrane Proteins; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D020558:GTP Phosphohydrolases; C579846:NRAS protein, human