Impact of Unplanned Treatment Gaps and Dose Rate Effect on Survival During Radiotherapy in Breast Cancer (BRIDGE study)
Ankita Pandey
, Ganesh Kumar Patel , Shreya Singh
Breast cancer, Overall treatment time, treatment interruption, Biological equivalent dose
Background Radiotherapy is an integral part of management in breast cancer that can be delivered by external beam or brachytherapy. Interruptions during radiotherapy are frequent and sometimes inevitable that may cause loss in the efficacy of the radiation. To account for real dose delivered after treatment gaps biological equivalent dose is calculated. The proposed study intended to evaluate effect of BED taking into account overall treatment time and source activity in brachytherapy on the outcome in breast cancer patients. Materials and methods This retrospective study included 50 patients of breast cancer after BCS who received WBRT followed by lumpectomy cavity boost by brachytherapy (Arm-A, n=20) and 6 MV photon EBRT (Arm-B, n=30). The prescribed dose of EBRT was 40Gy in 15 fractions with 2.67Gy dose per fraction. Boost dose delivered in both arms were 14Gy in 4fractions with 3.5Gy dose per fraction. The modified equation of BED was used for calculation taking into account overall treatment time, repopulation effect of tumor cells and intracellular time repair factor in brachytherapy. Results Median follow up duration of the cohort was 56 months (range: 30-89). All patients completed RT within 7weeks. Median treatment gap in Arm-A was 12.5days compared to 0.50days in Arm-B. Taking into account the time factor, mean calculated BED for late reacting tissue and tumor control was 94.27Gy3 and 81.54Gy4 in Arm-A and 101.7Gy3 and 88.40Gy4 in Arm-B, respectively. Median overall survival and disease free survival was 35 months (range: 24-45) and 32 months (range: 22-41). Three year OS and DFS were 94% and 88% respectively. Four patients in arm A and 2 in arm B developed loco-regional recurrence. Conclusion Overall treatment time and dose rate of brachytherapy source equally carries importance during treatment delivery and predicting the outcome. With prolong gap and decay in source activity, chances of local recurrence increases. Appropriate measures should be taken to minimize treatment interruption.
"Impact of Unplanned Treatment Gaps and Dose Rate Effect on Survival During Radiotherapy in Breast Cancer (BRIDGE study)", IJSDR - International Journal of Scientific Development and Research (www.IJSDR.org), ISSN:2455-2631, Vol.9, Issue 6, page no.214 - 221, June-2024, Available :https://ijsdr.org/papers/IJSDR2406026.pdf
Volume 9
Issue 6,
June-2024
Pages : 214 - 221
Paper Reg. ID: IJSDR_211654
Published Paper Id: IJSDR2406026
Downloads: 000347099
Research Area: Medical Science
Country: New Chandigarh, Punjab, India
DOI: https://doi.org/10.56975/ijsdr.v9i6.211654
ISSN: 2455-2631 | IMPACT FACTOR: 9.15 Calculated By Google Scholar | ESTD YEAR: 2016
An International Scholarly Open Access Journal, Peer-Reviewed, Refereed Journal Impact Factor 9.15 Calculate by Google Scholar and Semantic Scholar | AI-Powered Research Tool, Multidisciplinary, Monthly, Multilanguage Journal Indexing in All Major Database & Metadata, Citation Generator
Publisher: IJSDR(IJ Publication) Janvi Wave
