Pretransplant
blood transfusion has been shown to significantly affect the outcome of
renal transplantation. Evidence regarding the association of
blood transfusions with growth or recurrence of solid
tumors is still conflicting both in clinical and in experimental studies, although diminished survival has been suggested in several studies. To determine the influence of
blood transfusions and
hypovolemia, as separate or combined factors, on
tumor growth, we evaluated the weight of a subcutaneously implanted
sarcoma (
methylcholanthrene-induced) in 35 rats. After reaching 1%
tumor burden (day 0), the animals were separated into two groups:
hypovolemia (shed volume, 15 ml/kg) or normovolemia. These groups were further divided according to
resuscitation: OO (no
resuscitation), BL (receiving syngeneic blood stored in
citrate phosphate dextrose for 4 days, 15 ml/kg), SL (receiving 0.9%
sodium chloride, 45 ml/kg).
Tumor dimensions were determined daily by external measurement, and
tumor weight was calculated.
Hypovolemia exerted a significant influence on
tumor growth, independent of the
resuscitation modality. The rats that received
blood transfusions showed an increased rate of
tumor growth, compared to the animals that received
saline solution or no treatment. No interaction was noted between the effects produced by
hypovolemia and
blood transfusion. We conclude that the
hypovolemic event enhanced
tumor growth independently of the
resuscitation, and transfusion of
citrate phosphate dextrose-blood stored for 4 days did influence
tumor growth in this model. We suggest that the effect of
blood transfusion in patients with
cancer has to be redefined to account for the influence of possible
hypovolemic events.