A method of treating a mammalian subject having hematologic, non-tumorous cancer cells is disclosed. The method comprises the steps of: (A) administering to such a mammalian subject a therapeutically effective amount of a halogenated xanthene, a pharmaceutically acceptable salt or a C1-C4 alkyl ester thereof as a first cancer cytotoxic agent dissolved or dispersed in a pharmaceutically acceptable aqueous medium. The mammalian subject is maintained for a period of time sufficient to induce death of hematologic, non-tumorous cancer cells. A contemplated administration is typically repeated. A contemplated treatment method can also be carried out in conjunction with administration to said mammalian subject of a second therapeutically effective amount of a second, differently-acting cancer cytotoxic agent dissolved or dispersed in a pharmaceutically acceptable medium. The second cancer cytotoxic agent can be a small molecule or an intact antibody or paratope-containing portion thereof.