Stage 4 metastatic melanoma but curable / treatable?

Hi, im 44 and have been diagnosed with metastatic melanoma stage 4.  I had melanoma in my neck about 15 years ago which was removed and had Interferon treatment after (this stuff was another level).  I have been told that where the cancer is (in my thigh) that it is treatable and curable with surgery and Immunotherapy.  The last scan I had it wasnt anywhere else in my body.  I dont know if I am being blind to all this but reading stories online (even reputable information sources) my life expectancy is 5 to 10 years with treatment.  Im actually scared to ask the question to the consultant as I dont want to put myself back mentally.  Has anyone else been in a situation where they are stage 4 and classed as curable?