Fluorescence in situ hybridization for distinguishing nevoid melanomas from mitotically active nevi.
Nevoid melanoma may resemble benign compound or intradermal nevi by their silhouette and profile on low power. Higher power usually reveals nuclear atypia, confluence of cells, incomplete maturation and dermal mitotic activity. However, to some extent all of these features maybe seen in benign compound or intradermal nevi and no single criteria can be used to differentiate nevoid melanoma from a benign nevus. The distinction can be particularly problematic in nevi that show mitotic activity and we have noted a recent trend in diagnosis of melanocytic neoplasms with dermal mitosis as nevoid melanoma despite the presence of normal maturation in the dermis and lack of significant nuclear atypia. Therefore in this study we evaluated 10 nevoid melanomas, 4 of which resulted in metastasis and 10 mitotically active nevi with fluorescence in situ hybridization targeting key chromosomal loci previously shown to effectively discriminate been malignant and benign melanocytic neoplasms. All 10 nevoid melanomas showed copy number abnormalities by fluorescence in situ hybridization in either chromosome 6 or 11 while none of the 10 mitotically active nevi did. The results demonstrate that fluorescence in situ hybridization targeting key chromosomal loci on chromosomes 6 and 11 can be effective in discriminating nevoid melanomas from mitotically active nevi. Additionally, our study presents further evidence that dermal mitoses alone without other diagnostic features such as nuclear atypia and lack of maturation does not constitute sufficient evidence alone for a diagnosis of melanoma.
Gerami
Pedram
P
Northwestern University and the Feinberg School of Medicine and the Lurie Cancer Cancer, Chicago, IL 60611, USA. Pedram.Gerami@nmff.org
Wass
Amanda
A
Mafee
Mariam
M
Fang
Yuaquin
Y
Pulitzer
Melissa P
MP
Busam
Klaus J
KJ
D000293:Adolescent; D000328:Adult; D000369:Aged, 80 and over; D002869:Chromosome Aberrations; D002880:Chromosomes, Human, Pair 11; D002896:Chromosomes, Human, Pair 6; D019938:Cyclin D1 / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D020405:Dermis / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008545:Melanoma / Q000235:genetics* / Q000473:pathology; D008875:Middle Aged; D008938:Mitosis; D009506:Nevus / Q000235:genetics* / Q000473:pathology; D018330:Nevus, Intradermal / Q000235:genetics / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D020598:Proto-Oncogene Proteins c-myb / Q000235:genetics; D012878:Skin Neoplasms / Q000235:genetics* / Q000556:secondary; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics; D014481:United States; D055815:Young Adult
C530104:CCND1 protein, human; D004268:DNA-Binding Proteins; D020598:Proto-Oncogene Proteins c-myb; C101743:RREB1 protein, human; D014157:Transcription Factors; D019938:Cyclin D1