MOULD BRACHYTHERAPY LIP

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VISAKHAPATNAM,1/7-MVP[AP]
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2. Carcinoma lip- A organ preservation
approach by sandwich mould
Brachytherapy
DR K.C.PATRO, Radiation Oncologist
MR E.B. RAJMOHON, Medical Physicist

3. BACKGROUND
• Oral cancers account for 5-7% of all cancers
• And brachytherapy especially in oral cavity: important alternative to radical
surgery.
• It provides a high localized dose of radiation, with rapid fall-off and short
overall treatment time.
• [Mazeron et al. GEC-ESTRO recommendations for brachytherapy for head and neck squamous cell
carcinomas. Radiother Oncol 2009]
• Mould brachytherapy is technique of delivering brachytherapy by customised
applicator designed to provide a constant and reproducible frame for source
positioning.
• [Ariji et al. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999]
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4. BACKGROUND
• Local control rate more than 90% for T1 and T2N0 tumours with
brachytherapy alone.
– [Mazeron et al. GEC-ESTRO recommendations for brachytherapy for head and neck squamous cell
carcinomas. Radiother Oncol 2009]
• Mould therapy is indicated:
– in primary treatment for
• carcinomas of lip, floor of mouth, soft palate, or gingiva.
– T1/2 tumours with complete response for boost after ext beam
radiotherapy.
– Recurrent cases
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5. BACKGROUND
• Integration of imaging and optimization of dose distribution by improved
planning systems have helped in better tumour localization and improved
normal tissue definition
• Improving dose distribution to the tumour and reducing normal tissue
exposure.
• [Nag. High dose rate brachytherapy: its clinical applications and treatment guidelines. Technol
Cancer Res Treat. 2004]
• But there is paucity of both literature on the use of HDR mould
brachytherapy and the optimal time, dose and fractionation guidelines.
• [Fietkau. Activity Selectron Brachytherapy J. 1993; and Otti et al. Activity Selectron Brachytherapy J.
1992; Suppl 3]
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6. Lesion on lower lip and right angle of
mouth[2 skip lesion,no node]

7. MATERIALS AND METHODS
Mould preparation:
•The moulds prepared from thermoplastic + dental wax and customised.
•Double plane moulds with one plane on skin surface and one plane along
mucosal surface.
•Lesion marked by the oncologist, the physicist makes initial cut –out for the
mould with thermoplastic frame over which dental wax is layered.
•Mould matched with lesion surface and local anatomy; edges trimmed and
smoothened and required catheter positions marked into the mould
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8. Orfit frame

9. Wax mould on orfit

10. Flexible Implant tubes in mould

11. Applicator in situ with IOP

12. During treatment

13. Dose and dosimetry
• Total dose given was @ 3Gy twice daily for 15 #
• BED for 3 and 10 Gy was also calculated in all cases and the doses were less than 100
Gy in all cases for late toxicities.
• Dose was prescribed at 85% isodose .
• Isodose line in most cases to keep volume of tissue receiving greater than 200% of
prescribed dose to less than 20%
• CT-based planning helped identify volumes of tissue receiving dose greater than 150%
and optimising accordingly.
• Plans optimised so as to keep volumes receiving more than 200% within the mould.
• In all cases the organ at risk was the mandible and ALARA principle was followed.
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14. • After CT-simulation (3mm ST); image reconstruction, target volume
contouring and treatment planning done on Oncentra Planning System
• The target volume defined as tumour with a margin of 2 cm, specified by
the oncologist.
• The dosimetry was calculated using manual optimization techniques.
Treatments were delivered twice daily six hours apart and review of
reactions was done at regular interval
• Treatment delivery done on Flexitron HDR Brachytherapy.
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Treatment planning and delivery:

15. ISODOSE

16. DVH TABLE [PTV AND MANDIBLE DOSE]

17. Toxicity
• Patient completed radiation with grade 2 mucositis
Increased to grade 3 in 4 weeks. Healed properly in 6
weeks
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18. EARLY REACTION
HEALING WITH
HYPO-PIGMENTATION

19. 3 MONT FOLLOW-UP 9 MONTH FOLLOW-UP

20. ADVANTAGE
• NON INVASIVE
• NO ANAESTHESIA
• CR ACHIEVABLE

21. Acknowledgement
• DR.ASUTOSH MUKHERJEE
– ASST.PROF
– JIPMER,PONDYCHEHRRY

22. LET’S PRACTICE BRACHYTHERAPY