OBJECTIVES: The effect of direct local injection of dehydrated ethanol on hormone-independent prostatic carcinoma cells (PC3 cells) implanted in nude mice was investigated. METHODS: PC3 tumors were implanted subcutaneously into 30 nude mice. Three weeks later, dehydrated ethanol was injected directly into the tumors. Twenty-three animals received an injection of ethanol at a volume of 40 microL, 80 microL, or 160 microL, and were divided into a low-dose group (n = 11) and a high-dose group (n = 12) on the basis of the ethanol/tumor volume ratio (<30% versus> or =30%). The control group (n = 7) was injected with 40 microL of physiological saline. The tumor volume before treatment was 324.9 +/- 110.9 mm(3) and was assessed as well as 1 day, 4 days, 1 week, 2 weeks, and 3 weeks after injection. Then the changes of tumor volume were compared between the two ethanol groups (low-dose group and high-dose group) and the control group. Histological examination was performed for up to 3 weeks after injection. RESULTS: Assessment of tumor volume showed that the ethanol/tumor volume ratio was 16.1 +/- 5.3% in the low-dose group (n = 5) and 51.8 +/- 20.3% in the high-dose group (n = 6). Tumor growth was significantly inhibited after 1 and 2 weeks in the ethanol groups compared with the control group (n = 3). After 3 weeks, there was a tendency for tumor regrowth in the low-dose group, but growth inhibition was maintained in the high-dose group. Histological examination showed tumor degeneration and necrosis with feeding vessel obstruction in the acute phase. CONCLUSIONS: Local injection of dehydrated ethanol regressed tumors of prostatic carcinoma cells in nude mice, with the degeneration of tumor cells and occlusion of feeding vessels.
OBJECTIVES: The effect of direct local injection of dehydrated ethanol on hormone-independent prostatic carcinoma cells (PC3 cells) implanted in nude mice was investigated. METHODS:PC3tumors were implanted subcutaneously into 30 nude mice. Three weeks later, dehydrated ethanol was injected directly into the tumors. Twenty-three animals received an injection of ethanol at a volume of 40 microL, 80 microL, or 160 microL, and were divided into a low-dose group (n = 11) and a high-dose group (n = 12) on the basis of the ethanol/tumor volume ratio (<30% versus> or =30%). The control group (n = 7) was injected with 40 microL of physiological saline. The tumor volume before treatment was 324.9 +/- 110.9 mm(3) and was assessed as well as 1 day, 4 days, 1 week, 2 weeks, and 3 weeks after injection. Then the changes of tumor volume were compared between the two ethanol groups (low-dose group and high-dose group) and the control group. Histological examination was performed for up to 3 weeks after injection. RESULTS: Assessment of tumor volume showed that the ethanol/tumor volume ratio was 16.1 +/- 5.3% in the low-dose group (n = 5) and 51.8 +/- 20.3% in the high-dose group (n = 6). Tumor growth was significantly inhibited after 1 and 2 weeks in the ethanol groups compared with the control group (n = 3). After 3 weeks, there was a tendency for tumor regrowth in the low-dose group, but growth inhibition was maintained in the high-dose group. Histological examination showed tumor degeneration and necrosis with feeding vessel obstruction in the acute phase. CONCLUSIONS: Local injection of dehydrated ethanol regressed tumors of prostatic carcinoma cells in nude mice, with the degeneration of tumor cells and occlusion of feeding vessels.