Granulocytic sarcoma or chloroma is a tumor of immature cells from the granulocyte line that is generally associated with acute myeloid leukemia. The skin is one of the most affected organs. This lesion may complicate hematological dyscrasias, which is generally indicative of a poor prognosis. We present a case of a 51-year-old patient who was diagnosed with acute myeloid leukemia with a complex karyotype that debuted with a post-transplant cutaneous and hematological relapse, a very rare occurrence in the literature given that no extramedullary involvement was present prior to the transplant.