NRAS and cancer: In our previous study, performed with the AmpliSeq HotSpot cancer panel, asynchronous (9 cases) and synchronous (16 cases) metastatic lymph nodes and the corresponding primary melanoma tissues were sequenced and no significant differences in BRAF/NRAS mutation rates between primary (19 of 25; 76%) and metastatic (39 of 50; 78%) lesions were observed, indicating that BRAF/NRAS mutations may occur early in melanoma development, and their incidence may remain quite unvaried during melanoma progression [25].