Breast Cancer

PV QA 4 - Poster Viewing Q&A 4

TU_7_3387 - Historical Trends of Implantable Accelerated Partial Breast Irradiation Usage after Breast Conserving Surgery for Stage I Breast Cancer: A SEER Analysis

Tuesday, October 23
2:45 PM - 4:15 PM
Location: Innovation Hub, Exhibit Hall 3

Historical Trends of Implantable Accelerated Partial Breast Irradiation Usage after Breast Conserving Surgery for Stage I Breast Cancer: A SEER Analysis
Z. A. Siddiqui, C. C. Vu, A. Thompson, J. T. Dilworth, and P. Y. Chen; Dept. of Radiation Oncology, Beaumont Health, Royal Oak, MI

Purpose/Objective(s): To evaluate the historical trends in the use of implantable accelerated partial breast (IAPBI) to treat Stage I breast cancer in the adjuvant setting after breast-conserving surgery.

Materials/Methods: The Surveillance, Epidemiology, and End Results (SEER) database was queried for patients from 2000 to 2014 with Stage I breast cancer that underwent lumpectomy and adjuvant radiation therapy (either IAPBI or external beam radiotherapy). The percentage of patients receiving IAPBI was recorded for different cohorts based on age (<40, 40-49, 50-59, 60-69, 70+), estrogen/progesterone receptor status, tumor grade and tumor size (0-9mm, 10-19mm, 20-29mm, 30+ mm). Statistics are reported on a per-year basis.

Results: Of 193,724 eligible patients, 181,886 (94%) underwent external beam radiation and 11,838 (6%) received IAPBI. Both the total number and percentage of patients undergoing IAPBI increased every year from 2000 (56 patients, 0.5%) through 2008 (1,232 patients, 9.51%). From 2008 – 2011, the total number of patients treated with IAPBI continued to gradually increase (1,330 patients in 2011) though the percentage remained stable (maximum of 9.5% in 2010). However, these numbers dropped through 2014 (1,096 patients, 7.4%). The percentage decline for all patients from 2010 to 2014 was 21%. The use of IAPBI decreased by more than this average for the following cohorts: ER-negative (35%), age 70+ (26%) and grade 3 histology (27%).

Conclusion: There has been a decrease in the use of IAPBI since 2010, with a larger decline in hormone-negative patients, high-grade patients, and elderly patients. Further analysis is needed to verify the robustness of these findings. These patterns are consistent with publications in 2009-2010 describing consensus guidelines for IAPBI use and mature data from randomized trials showing good outcomes for hypofractionated whole breast radiotherapy and the omission of radiotherapy in low-risk elderly patients.

Author Disclosure: Z.A. Siddiqui: None. C.C. Vu: None. A. Thompson: None. P.Y. Chen: Stock; Greater Michigan Gamma Knife (GMGK).

Send Email for Zaid Siddiqui


Assets

TU_7_3387 - Historical Trends of Implantable Accelerated Partial Breast Irradiation Usage after Breast Conserving Surgery for Stage I Breast Cancer: A SEER Analysis



Attendees who have favorited this

Please enter your access key

The asset you are trying to access is locked. Please enter your access key to unlock.

Send Email for Historical Trends of Implantable Accelerated Partial Breast Irradiation Usage after Breast Conserving Surgery for Stage I Breast Cancer: A SEER Analysis