Authors: Lena Marinova, Vaska Vassileva, Iliya Gabrovski, Galin Vulchev, Viktor Petrov.
Diffuse intrinsic pontine glioma (DIPG) is an aggressive primary pediatric brain tumor. Despite the application of various curative methods, including radiotherapy (RT) with or without chemotherapy (Ch), targeted agents and immunological approaches, there is no achievement of clear improvement in median overall or progression-free survival (PFS).
We present a 6-year-old girl with DIPG after a 3 D conformal radiotherapy (3D CRT) in the brain stem tumor with a 1.5 cm insurance zone, by three fractions gradually rising daily doses (DD) 1,6 Gy -1,8 Gy -2.2 Gy, followed by 11 fractions hypofractionated RT with DD 3 Gy up to total dose (TD) 33 Gy. The sum of total tumor dose is 38.6 Gy, corresponding to a biological equivalent dose to 2 Gy/ equieffective dose (EQD2) 46.71 Gy. After 8 months, due to local tumor progression, local tumor re-irradiation up to TD 20 Gy with DD 2 Gy was performed. In children with rapidly enhancing neurological symptoms and worsened forecast, it is appropriate to carry out hypophractionated RT up to 45 Gy with DD 3 Gy in 15 fractions, which achieves PFS similar to conventional fractionated RT.
Our observations from the realized RT are that despite highly risky tumor localization, hypophractionated RT is well tolerated, without acute neurological toxicity and allows second irradiation / re-irradiation, due to local tumor progression.
View/Download pdf