IL2 and basal cell carcinoma: Concerning the four grade 3 severe CTCAEs unrelated to TILs or Proleukin® (IL-2), nivolumab has the following characteristics: ‘alteration of general condition’, ‘basal cell carcinoma’, and ‘haemorrhagic stroke’ regressive with minimal sequelae such as psychomotor slowing and ‘infiltrating carcinoma of the right breast’.