IORT: the future of breast cancer treatment?
Faculty Advisor Name
Abby Massey
Department
Department of Health Professions
Description
Introduction:
Research focus: unifocal, invasive breast cancers classified as T1-T2, N0-N1, and M0. These tumors measure less than 5 cm, have not spread beyond the axillary lymph nodes, and have not spread to distant organs. Treatment includes lumpectomy of the tumor followed by radiation.
Whole breast external beam radiotherapy (EBRT): traditional treatment; three-to-four-week course, five days a week.
Intraoperative radiotherapy (IORT): single dose of radiation directly to the tumor bed immediately post-lumpectomy, allowing both surgery and radiation to be completed in one day.
Objective: Assess the 5 year local recurrence rate of intraoperative radiotherapy (IORT) in relation to the conventional treatment of external breast radiotherapy (EBRT) in eligible females diagnosed with breast cancer over age 40.
Design: Systematic literature review.
Methods: PubMed was searched using the following limits and terms: breast neoplasms, intraoperative radiotherapy, randomized control trial, clinical trial, females, English, and published in the last 10 years.
Results: Upon this search, three studies were found to directly compare IORT and EBRT regarding 5 year local recurrence rates.
Study #1 showed no significant difference between women who received IORT and those who received EBRT when looking at local tumor recurrence. However, a very small number of participants were in the IORT group: only 77 compared to 170 women in the control group. Further, women less than 48 years old were given both IORT and EBRT, thus cannot be included in the analysis. The study was also non-randomized.
Study #2 showed that intraoperative radiotherapy resulted in significantly higher local recurrence, although still within the equivalence margin. However, there was no blinding or masking noted.
Study #3 showed more local recurrences in the TARGIT group than EBRT, but within the non-inferiority margins set prior to the study. However, the TARGIT group received supplemental EBRT if unforeseen adverse features were detected on final pathology, and there was no stated attempt to blind patients.
Conclusion: IORT was shown to be non-inferior to EBRT in two of the three studies that were examined; however, more research is necessary to confidently establish this. The benefits of IORT, including convenience, length of treatment, and side effect profile, deem further study worthwhile. The full risk-benefit profile of both radiotherapy options should be discussed with eligible patients in shared decision-making tailored to each individual. The significant benefits of IORT, including convenience and minimization of side effects, make it a reasonable alternative to EBRT. If studies continue to prove non-inferiority, IORT could become standard of care for breast cancer patients post-lumpectomy.
IORT: the future of breast cancer treatment?
Introduction:
Research focus: unifocal, invasive breast cancers classified as T1-T2, N0-N1, and M0. These tumors measure less than 5 cm, have not spread beyond the axillary lymph nodes, and have not spread to distant organs. Treatment includes lumpectomy of the tumor followed by radiation.
Whole breast external beam radiotherapy (EBRT): traditional treatment; three-to-four-week course, five days a week.
Intraoperative radiotherapy (IORT): single dose of radiation directly to the tumor bed immediately post-lumpectomy, allowing both surgery and radiation to be completed in one day.
Objective: Assess the 5 year local recurrence rate of intraoperative radiotherapy (IORT) in relation to the conventional treatment of external breast radiotherapy (EBRT) in eligible females diagnosed with breast cancer over age 40.
Design: Systematic literature review.
Methods: PubMed was searched using the following limits and terms: breast neoplasms, intraoperative radiotherapy, randomized control trial, clinical trial, females, English, and published in the last 10 years.
Results: Upon this search, three studies were found to directly compare IORT and EBRT regarding 5 year local recurrence rates.
Study #1 showed no significant difference between women who received IORT and those who received EBRT when looking at local tumor recurrence. However, a very small number of participants were in the IORT group: only 77 compared to 170 women in the control group. Further, women less than 48 years old were given both IORT and EBRT, thus cannot be included in the analysis. The study was also non-randomized.
Study #2 showed that intraoperative radiotherapy resulted in significantly higher local recurrence, although still within the equivalence margin. However, there was no blinding or masking noted.
Study #3 showed more local recurrences in the TARGIT group than EBRT, but within the non-inferiority margins set prior to the study. However, the TARGIT group received supplemental EBRT if unforeseen adverse features were detected on final pathology, and there was no stated attempt to blind patients.
Conclusion: IORT was shown to be non-inferior to EBRT in two of the three studies that were examined; however, more research is necessary to confidently establish this. The benefits of IORT, including convenience, length of treatment, and side effect profile, deem further study worthwhile. The full risk-benefit profile of both radiotherapy options should be discussed with eligible patients in shared decision-making tailored to each individual. The significant benefits of IORT, including convenience and minimization of side effects, make it a reasonable alternative to EBRT. If studies continue to prove non-inferiority, IORT could become standard of care for breast cancer patients post-lumpectomy.
