The Collaborative International Dictionary of English v.0.48:

Leuchaemia \Leu*ch[ae]"mi*a\ (l[-u]*k[=e]"m[i^]*[.a]), n. [NL.,
   fr. Gr. leyko`s white + a"i^ma blood.] (Med.)
   See Leukemia. [Written also leukemia, leukaemia,a nd
   leucemia.]
   -- Leu*ch[ae]m"ic (l[-u]*k[e^]m"[i^]k), a. [Written also
   leukemic and leukaemic.]
   [1913 Webster] Leucic

WordNet (r) 3.0 (2006):

leukemia
    n 1: malignant neoplasm of blood-forming tissues; characterized
         by abnormal proliferation of leukocytes; one of the four
         major types of cancer [syn: leukemia, leukaemia,
         leucaemia, cancer of the blood]

Moby Thesaurus II by Grady Ward, 1.0:

32 Moby Thesaurus words for "leukemia":
   Christmas disease, Hand-Schuller-Christian disease,
   Letterer-Siwe syndrome, acute leukemia, anemia, angiohemophilia,
   aplastic anemia, chronic leukemia, cyclic neutropenia,
   erythrocytosis, hemoglobinopathy, hemophilia, hemophilia A,
   hemophilia B, hypochromic anemia, infectious granuloma,
   iron deficiency anemia, leukemic reticuloendotheliosis,
   macrocytic anemia, multiple myeloma, myelogenous leukemia,
   neutropenia, pernicious anemia, plasma cell leukemia, plasmacytoma,
   polycythemia, pseudoleukemia, purpura, purpura hemorrhagica,
   sickle-cell anemia, thalassemia, vascular hemophilia