The patients will receive a standard dose, or a reduced amount of the immune suppressive drug, cyclophosphamide, that is routinely administered after the transplant procedure. The following procedures will be performed: cardiac MRI scans and/or transthoracic echocardiogram (TTE); laboratory tests, geriatric assessments and tests to measure strength and stability.~Participation in the study is expected to last up to one year with follow-up visits occurring on Day +30, Day +100, Day +180 and Day +365 following allogenic stem cell transplant.
The purpose of this phase 1 study is to determine the optimal dose of the immune suppressive drug, cyclophosphamide, following standard allogeneic stem cell transplant in patients aged >/= 70 years with hematologic malignancies.