title: Atypical amplification of chromosome region 22q12 in melanoma: A case report.
abstract: Morphological, ultrastructural and immunohistochemical characteristics of clear cell sarcoma (CCS) of the soft tissue frequently overlap with those of malignant melanoma. Thus, the differential diagnosis between the two lesions represents an important diagnostic dilemma. However, a number of genetic factors can be used to differentiate the two tumors; in particular, the t(12;22)(q13;q12) chromosomal translocation is typical of CCS, resulting in fusion of theEWSR1gene on chromosome 22q12 and theATF1gene on chromosome 12q13. The detection of this molecular alteration has proved useful in the differential diagnosis of the two lesions. The present study reports the case of a 71-year-old male patient with a suspicious lymph node mass. Immunohistochemical analysis of the lesion indicated a diagnosis of metastatic melanoma, however, cytogenetic analysis using fluorescencein situhybridization was additionally performed to investigate the chromosomal rearrangements of the 22q12 region and completely exclude the possibility of CCS. The current case did not demonstrate the presence of the translocation, supporting the diagnosis of melanoma. However, a clear orange amplification signal was observed relative to an ~500-kb region adjacent to theEWSR1gene in the centromeric direction of chromosome 22q12. To the best of our knowledge, this is the first description of a 22q12 chromosomal alteration in melanoma. Furthermore, despite the presence of numerous genes in this region, their amplification has not previously been associated with the pathogenesis of melanoma.
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Liguori
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Cantile
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Collina
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Marra
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: DE Chiara
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Franco
authors.affiliation: Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples 80138, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Caraglia
authors.affiliation: Pathology Unit, National Cancer Institute IRCCS 'Fondazione G. Pascale', Naples 80131, Italy.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Botti
authors.affiliation: Department of Medical-Surgical and Dental Specialities, Second University of Naples, Naples 80138, Italy.
authors.forename: Mirella
authors.initials: M
authors.lastname: D'Andrea
authors.affiliation: Department of Medical-Surgical and Dental Specialities, Second University of Naples, Naples 80138, Italy.
authors.forename: Giovanni Francesco
authors.initials: GF
authors.lastname: Nicoletti
keywords: EWSR1 gene; chromosomal translocation; clear cell sarcoma; differential diagnosis; fluorescence in situ hybridization