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Global Gene Expression Fails to Discriminate Thin Melanomas with Poor Outcomes

ABSTRACT: Melanoma is the fifth-most common cancer diagnosed in the United States with a dramatic increase in incidence among both men and women. Most melanomas present as thin lesions (≤1.0mm) and have a good prognosis. However a small percentage of patients (5-10%) with thin lesions recur or metastasize. The aim of our study was to elucidate which thin melanomas (< 1.0 mm thickness) have the propensity to metastasize to regional lymph nodes or distant sites. Our focus was analyzing gene expression as a whole. We sought to identify a distinct pattern of gene expression within thin melanomas that were known to have eventually metastasized to regional lymph nodes or distant sites, from those that followed the typical course with good response to wide local excision alone. While gene expression differences were observed between nine thin melanoma patients with poor clinical outcome compared to ten patients with a good clinical outcome, neither the number of genes nor the magnitude of the fold difference was very substantial or significant. Although cluster analysis was able to use this subset of genes to definitively separate a subset of the poor responders from the good responders, there remained a mixed group of tumors which could not be predicted from gene expression alone. Pathway analysis did identify cellular processes that were regulated based upon response, including categories commonly associated with melanoma progression The goal of this pilot study was to identify gene expression changes within the tumor cells of thin melanomas that have a poor outcome that would discriminate them from thin melanomas that do not recur or metastasize . Our results conclude that there were very few differences between these groups. Future research will be required and investigation of the mutational landscape of these different tumor sub-types may be another strategy to uncover genomic changes that drive recurrence and metastasis.

ORGANISM(S): Homo sapiens

PROVIDER: GSE79662 | GEO | 2017/01/15

SECONDARY ACCESSION(S): PRJNA316616

REPOSITORIES: GEO

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Global Gene Expression Fails to Discriminate Thin Melanomas with Poor Outcomes

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