[Mutational tumor profiles beyond organ and tissue specificity: implications for diagnostics and clinical study...

The diagnostics and therapy of malignant tumors are based on the paradigm that cancer is an organ and tissue-specific disease. Comprehensive tumor mutation profiling data that has recently become available from next generation sequencing projects has made it possible to analyze whether the established anatomical tumor classification is reflected on the genetic level. Here, we review the results of a study on 4796 tumors of 14 major cancer types from the cancer genome atlas (TCGA) database, that on average 43% of tumors of a particular type are genetically more similar to tumors of a different anatomical origin and that the genetic tumor type corresponds to the anatomical type in only 57% of the cases. Furthermore, we discuss the implications of the complex mutation profiles and similarity patterns across cancers for diagnostics and clinical study design and explain why the comprehensive genomic data should be complemented by functional proteomic analyses.