24 Rectal Cancer

Rectal Cancer

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THE GEC ESTRO HANDBOOK OF BRACHYTHERAPY | Part II: Clinical Practice Version 1 - 10/12/2014

Fig 25 HDR endoluminal brachytherapy for rectal cancer

Fig 25.5a Radiograph of rectal endoluminal applicator with dummy wires and gold marker seeds indicating tumor borders

Fig 25 5.e CTV (Tumour +5mm) and axial dose distribution with the multi-channel flexible rectal applicator showing the effect of the water stand-off balloon (Courtesy of Dr Te Vuong)

Fig 25.5b Sagittal CT with endoluminal applicator, target volume, dwell positions and isodose lines

Fig 25.5f Isodose distribution showing effect of quadrant shielding on the dosimetry

Fig 25.5c Diagram of multi-channel intraluminal rectal brachytherapy with loading positions in posterior part of the applicator for the posterior residual tumour. No loading on the contra lat- eral side to reduce dose to the non-involved normal rectal mucosa not involved by the tumour. Balloon can also be used to push the normal rectal mucosa away from the loaded positions.

Fig 25.5d Cross section of flexible rectal applicator showing the dimensions, the catheter num- bering (4-11) and the calculation points (A-H) midway between each catheter, 10 mm from the applicator surface

Figure 25.5g. Showing rectal HDR endoluminal brachytherapy applicator in treatment position