Ewing sarcoma mimicking atypical carcinoid tumor: detection of unexpected genomic alterations demonstrates the use of next generation sequencing as a diagnostic tool

Increasingly, tumors are being analyzed for a variety of mutations and other genomic changes, with the goals of guiding personalized therapy and directing patients to appropriate clinical trials based on genotype, as well as identifying previously unknown genomic changes in different tumor types and thereby providing new insights into the pathogenesis of human cancers. Next generation sequencing is a powerful research tool now gaining traction in the clinic. In this report, we demonstrate the utility of next generation sequencing assays in providing diagnostic information when evaluating tumor specimens. This is illustrated by a case previously thought to represent an atypical carcinoid tumor, in which an EWSR1-ERG translocation was detected during next generation sequencing using a hybrid capture approach, leading to a revised diagnosis of Ewing sarcoma. The role of translocation detection in these assays is also discussed.