This is a pilot study to evaluate the efficacy of hyperbaric oxygen therapy (HBO2) for
mobilizing hematopoietic progenitor cells from bone marrow to blood. These cells are needed
for patients to undergo bone marrow transplantation and some patients fail to respond to
current best chemotherapy. HBO2 has been shown to trigger stem cell mobilization in other
patient populations and we plan to investigate whether this intervention can act in concert
with chemotherapeutic agents to allow poor mobilizer patients to achieve successful bone
marrow transplantation. Twenty patients will be identified by participating hematologists who
have failed to respond adequately to chemotherapy. When it is deemed appropriate to attempt
an additional stem cell mobilization protocol, these patients will be administered
chemotherapy as determined by their primary treating hematologist and additionally receive
daily HBO2 (2.5 atmospheres absolute [ATA] for 90 minutes) for 3-8 days. At intervals, blood
samples will be obtained as is the normal transplantation protocol practice to assess whether
adequate stem cells are present in blood for the patient to proceed with transplantation. The
project is anticipated to take one year to complete.