23. Anal Cancer - The GEC-ESTRO Handbook of Brachytherapy

Anal Cancer

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THE GEC ESTROHANDBOOKOF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 01/03/2023

Figure 8 - Example of a planning CT scan

Figure 9: Example of a dosimetry according to the Paris system with 6 needles in a single implant plane Some isodose lines are represented: the yellow isodose corresponds to 20 Gy (the prescribed reference isodose), the blue isodose to 16 Gy, the light green to 12Gy and the dark green to 8 Gy. The contralateral mucosa received thus a dose lower than 8 Gy, limiting toxicities.