Читать книгу Intracranial Gliomas Part II - Adjuvant Therapy - Группа авторов - Страница 53

Intensity-modulated radiation therapy (IMRT) combines inverse planning software algorithms and the subdivision of fields into tiny “beamlets” to provide highly conformal high-dose distributions. Moreover, differential dosing of target structures allows for simultaneous integrated boost (SIB) techniques by which a high-risk region may receive a target boost dose while simultaneously a lower risk region is delivered a reduced dose. At MD Anderson Cancer Center, this technique is commonly employed to offer a higher degree of target conformity while minimizing dose to nearby critical structures and non-involved brain [14, 15]. Utilizing SIB technique the PTV boost volume receives 60 Gy in 30 fractions over 6 weeks while, at the same time, the larger PTV volume receives 50 Gy (Fig. 1).

Fig. 1. A 56-year-old man underwent gross total resection of glioblastoma. Postoperatively he received simultaneously 60 Gy in 30 fractions to a 2 cm margin of the surgical cavity and 50 Gy in 30 fractions to a 2 cm margin beyond residual T2/FLAIR hyperintensity with an appropriate setup margins. This CTV was reduced along anatomical barriers such as the falx and calvarium.