It is well known that malignant tumor have hypoxic cell fraction, which is radio resistant and is one of the most important cause of local recurrence after radiotherapy. One of the causes of hypoxia in tumor is blood flow decrease due to increase in blood flow resistance and one of the causes of increased blood flow resistance could be attributed to the increase in blood viscosity. For the evaluation of the change of blood viscosity in oral cancer, experiments were carried out to test the change of blood viscosity among the normal control and xenografted oral cancer nude mice. Relative viscosity measured against distilled water was 3.300.14 for normal control, and 3.67 0.62 for tumor bearing mice at the first time of blood sampling in experimental period (100 mm3 <tumor volume<200 mm3). There was no statistically significant difference between the control group and experimental group (p>0.05). However, as the tumor grew, significant difference of blood viscosity was detected at the third time of blood sampling (control group:3.37 0.59, and experimental group: 4.31 0.41 300 mm3 <tumor volume, p<0.05). Increase in blood viscosity was confirmed with this experimental study and it can be postulated that modification blood viscosity might contribute to decrease of hypoxia fraction in oral cancer, thus improve the effect of radiotherapy.

It is well known that malignant tumor have hypoxic cell fraction, which is radio resistant and is one of the most important cause of local recurrence after radiotherapy. One of the causes of hypoxia in tumor is blood flow decrease due to increase in blood flow resistance and one of the causes of increased blood flow resistance could be attributed to the increase in blood viscosity. For the evaluation of the change of blood viscosity in oral cancer, experiments were carried out to test the change of blood viscosity among the normal control and xenografted oral cancer nude mice. Relative viscosity measured against distilled water was 3.300.14 for normal control, and 3.67 0.62 for tumor bearing mice at the first time of blood sampling in experimental period (100 mm3 <tumor volume<200 mm3). There was no statistically significant difference between the control group and experimental group (p>0.05). However, as the tumor grew, significant difference of blood viscosity was detected at the third time of blood sampling (control group:3.37 0.59, and experimental group: 4.31 0.41 300 mm3 <tumor volume, p<0.05). Increase in blood viscosity was confirmed with this experimental study and it can be postulated that modification blood viscosity might contribute to decrease of hypoxia fraction in oral cancer, thus improve the effect of radiotherapy.

oral cancer, blood viscosity