IL2 and neoplasm: This tumor is often regarded as immunogenic based on the observation of a 4% spontaneous regression in metastatic lesions [11-13], the abundant presence of tumor infiltrating lymphocytes (TIL) in tumor specimens, and the well-documented responses to some immuno-cytokines (Interleukin-2 [IL-2] and Interferon-α [IFN-α]) and vaccine therapy [14].