Purpose: We evaluated the in vivo efficacy of external beam radiation therapy (EBRT) utilizing a clinical fractionation scheme and correlated this with previous experimental data in the murine hereditary transgenic retinoblastoma model. Methods: Ten 5 week-old SV40 Tag positive mice were entered into a control group receiving no treatment, and 60 SV40 Tag mice (6 mice/treatment point) were treated with EBRT utilizing one of two fractionation schemes at total doses of either 10, 15, 20, 30, 40, 45 or 50 Gray (Gy) of 500 centigray (cGy) twice daily treatment or 36, 56, or 76 Gy of 200 cGy once daily treatment. Animals were sacrificed at 10 weeks post-treatment and the eyes were obtained for serial section, histopathologic examination. Results: 100 % (10/10) of control eyes contained multiple, large retinal tumor foci. Dose dependent, fractionation dependent tumor control curves were generated. The 50% control point for elimination of ocular tumors occurred at 28 Gy for the 500 cGy bid treated eyes and at 51 Gy for the 200 cGy qd treated eyes. Statistical comparison generated 95% confidence intervals and a p-value of 0.001 between the two dose response curves. Conclusion: Dose fractionation significantly affects tumor control within this murine transgenic retinoblastoma model and clinically relevant dose fractionations (i.e. 200 cGy) are associated with tumor control.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience