CPB Ljubljana 2018 course book

Practical session, day 3, Needle reconstruction and treatment planning

Learning objective: -

Needle reconstruction;

- Activation of necessary dwell positions; - Treatment planning and optimization.

Case description. This patient presented with a squamous cell carcinoma of the right vaginal wall, 3 (width) x 4.5 (thickness) x 4 cm (length). External beam radiotherapy was given to a dose of 23 x 2 Gy. Tumor size at time of brachytherapy was 2 (width) x 3 (thickness) x 3 cm (length). A perineal implant with 7 needles was performed. A PDR brachytherapy boost of 48 pulses of 60 cGy was given every 1 hour.

1) Reconstruction of the catheters.

2) Paris system dosimetry. a) Activate the dwell positions. Which dwell positions need to be activated? b) Locate the basal dose point(s). c) Make a treatment plan. d) If plan is not optimal, optimize to have a clinical acceptable plan (see dose constraints below).

3) Treatment plan on target points a) Place target points of the surface of the CTV/PTV b) Activate the dwell positions. Which dwell positions need to be activated? c) Make a treatment plan. d) If plan is not optimal, optimize to have a clinical acceptable plan (see dose constraints below).