In detail, we will summarize the data on the molecular mechanisms involved in RET/PTC formation and in its function as a dominant oncogene, on the activated signal transduction pathways and on the induced gene expression modifications.     ///    Intracellular signal transduction and modification of the tumor microenvironment induced by RET/PTCs in papillary thyroid carcinoma..     ///    "In this review, we will examine the mechanisms involved in RET/PTC-induced thyroid cell transformation. "    ///    "Finally, a short review of the literature on RET/PTC prognostic significance will be presented.. "    ///    "Moreover, we will report on the effects of RET/PTCs on the tumor microenvironment. "