(442m) Enhanced Tumor Oxygenation with Hemoglobin Based Oxygen Carriers


A major obstacle to successful tumor therapy via radiation/chemo therapy is the low partial pressure of oxygen in the tumor. Since tumors grow quickly, the capillary network inside the tumor is usually undeveloped resulting in hypoxic conditions in the surrounding tissue. In order to improve radiation therapy, previous reseach efforts have centered on methods to improve tumor oxygen tension to increase tumor sensitivity to radiation/chemo therapy. A blood substitute (oxygen carrier) with increased oxygen affinity, low P50, could target oxygen delivery to hypoxic tumor tissue by only releasing oxygen when the tissue pO2 approaches hypoxic levels. The finite element method was used to simulate the oxygen tension within cancerous tissue using P50s corresponding to different hemoglobin-based oxygen carriers (HBOCs). Oxygen transport simulations showed that at low entering capillary pO2s', HBOCs with P50s below the entering pO2 of the capillary were able to supply more oxygen to the tissue and raise the average tissue pO2. Thus, an HBOC with tailored oxygen binding properties (P50) could be used to target oxygen delivery to hypoxic tumor tissue, making the tumor more sensitive to radiation/chemo therapy and increasing the overall success of the treatment regime.