Predictors of Heart and Lung Dose in Left-sided Breast Cancer Treated with VMAT Relative to 3D-CRT：A Retrospective Study

Abstract Background Before radiotherapy for breast cancer patients, the choice of three-dimensional conformal radiation therapy (3D-CRT) and volumetric modulated arc therapy (VMAT) should be made. This study investigates the performance of two structural metrics in aiding the choice of 3D-CRT and VMAT plans in women undergoing left-sided whole breast radiotherapy. Materials and methods 119 patients previously treated with left-sided breast radiotherapy (61 3D-CRT treatments and 58 VMAT treatments) from a single institution were retrospectively studied. Two structural metrics, which are cardiac intersetion (CI) index and pulmonary intersection (PI) index, were defined and the relationship between these metrics and dose of organs at risk (OARs) were evaluated. Two-tailed Student’s t-test was performed to compare patient characteristics between 3D-CRT and VMAT. Linear regressions were calculated to investigate the association between structural metrics and absorbed dose of heart and left lung, including MHD, V5, V30 of heart, and MLLD, V5, V10, V20, V30, V40 of left lung. Results The CI index was strongly correlated with the mean dose of heart (MHD) in 3D-CRT group and VMAT group, the linear regression formulas were MHD = 4826.59 ×CI Index + 310.48 (R = 0.857, F = 163.77, P = 0.000) in 3D-CRT plans and MHD = 1789.29×CI Index + 437.50 (R = 0.45, F = 14.23, P = 0.000) in VMAT plans, the intercept of these formulas was CI index = 4.2% and MHD = 512.33 cGy. The PI index demonstrated a strongly positive correlation with mean dose of left lung (MLLD) in 3D-CRT group and VMAT group as well, the linear regression formulas were MLLD = 2879.54×PI Index + 999.79 (R = 0.697, F = 55.86, P = 0.000) in 3D-CRT plans and MLLD = 1411.79×PI Index + 1091.88 (R = 0.676, F = 47.11, P = 0.000) in VMAT plans, the intercept of these formulas was PI index = 6.3% and MLLD = 1180.46 cGy. Conclusions CI index and PI index could serve as a practical tool of choosing either 3D-CRT or VMAT before the plan was generated. We recommend that VMAT plan is preferable when CI index is greater than 4.2% and PI index is greater than 14.6%, while 3D-CRT plan is the first choice in the opposite.

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Predictors of heart and lung dose in left-sided breast cancer treated with VMAT relative to 3D-CRT: A retrospective study

PLoS ONE ◽

10.1371/journal.pone.0252552 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0252552

Author(s):

Zheng Kang ◽

Sijia Chen ◽

Liwan Shi ◽

Yipeng He ◽

Xiang Gao

Keyword(s):

Breast Cancer ◽

Linear Regression ◽

Organs At Risk ◽

Left Lung ◽

Breast Cancer Patients ◽

Breast Radiotherapy ◽

Conformal Radiation Therapy ◽

Whole Breast Radiotherapy ◽

First Choice ◽

3D Crt

Background Before generating radiotherapy plans for breast cancer patients, the choice of plan techniques (three-dimensional conformal radiation therapy (3D-CRT) and volumetric modulated arc therapy (VMAT)) should be made. This study investigated the performance of two geometric indices in aiding the choice of 3D-CRT and VMAT plans in women undergoing left-sided whole breast radiotherapy. Materials and methods 119 patients, previously treated with left-sided breast radiotherapy (61 3D-CRT treatments and 58 VMAT treatments) from a single institution, were retrospectively studied. Two geometric indices, which were cardiac junction (CJ) index and pulmonary junction (PJ) index, were defined and the relationship between these indices and dose of organs at risk (OARs) were evaluated. Two-tailed Student’s t-test was performed to compare patient characteristics between 3D-CRT and VMAT. Linear regressions were calculated to investigate the association between geometric indices and absorbed dose of heart and left lung, including mean dose of heart (MHD), V5, V30 of heart, and mean dose of left lung (MLLD), V5, V10, V20, V30, V40 of left lung. Results The CJ index was strongly correlated with the MHD in 3D-CRT group and VMAT group. The linear regression formulas were MHD = 4826.59 ×CJ Index+310.48 (R = 0.857, F = 163.77, P = 0.000) in 3D-CRT plans and MHD = 1789.29×CJ Index+437.50 (R = 0.45, F = 14.23, P = 0.000) in VMAT plans. The intersection of the two formulas was CJ index = 4.2% and MHD = 512.33 cGy. The PJ index demonstrated a strongly positive correlation with MLLD in 3D-CRT group and VMAT group as well. The linear regression formulas were MLLD = 2879.54×PJ Index+999.79 (R = 0.697, F = 55.86, P = 0.000) in 3D-CRT plans and MLLD = 1411.79×PJ Index+1091.88 (R = 0.676, F = 47.11, P = 0.000) in VMAT plans, the intersection of the two formulas was PJ index = 6.3% and MLLD = 1180.46 cGy. Conclusions CJ index and PJ index could be used as a practical tool to select 3D-CRT or VMAT before generating plans. We recommend that VMAT plan is preferable when CJ index is greater than 4.2% and/or PJ index is greater than 14.6%, while 3D-CRT plan is the first choice in the opposite.

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Faculty Opinions recommendation of Patients with t1 to t2 breast cancer with one to three positive nodes have higher local and regional recurrence risks compared with node-negative patients after breast-conserving surgery and whole-breast radiotherapy.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1120627.576846 ◽

2008 ◽

Author(s):

Alphonse Taghian ◽

Mohamed Alm El-Din

Keyword(s):

Breast Cancer ◽

Breast Conserving Surgery ◽

Regional Recurrence ◽

Breast Radiotherapy ◽

Node Negative ◽

Whole Breast Radiotherapy

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Faculty Opinions recommendation of Targeted intraoperative radiotherapy versus whole breast radiotherapy for breast cancer (TARGIT-A trial): an international, prospective, randomised, non-inferiority phase 3 trial.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.3970957.3729056 ◽

2010 ◽

Author(s):

Jacques Bernier ◽

Conny Vrieling

Keyword(s):

Breast Cancer ◽

Intraoperative Radiotherapy ◽

Breast Radiotherapy ◽

Phase 3 ◽

Whole Breast Radiotherapy

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The TARGIT trial: targeted intraoperative radiation therapy versus conventional postoperative whole-breast radiotherapy after breast-conserving surgery for the management of early-stage invasive breast cancer (a trial update)

The American Journal of Surgery ◽

10.1016/j.amjsurg.2007.06.018 ◽

2007 ◽

Vol 194 (4) ◽

pp. 507-510 ◽

Cited By ~ 55

Author(s):

Dennis R. Holmes ◽

Michael Baum ◽

David Joseph

Keyword(s):

Breast Cancer ◽

Radiation Therapy ◽

Invasive Breast Cancer ◽

Early Stage ◽

Breast Conserving Surgery ◽

Intraoperative Radiation Therapy ◽

Breast Radiotherapy ◽

Intraoperative Radiation ◽

Whole Breast Radiotherapy

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Deep-inspiration breath hold radiotherapy in patients with left-sided breast cancer after partial mastectomy

10.33699/pis.2021.100.4.180-185 ◽

2021 ◽

Vol 100 (4) ◽

Keyword(s):

Breast Cancer ◽

Radiation Dose ◽

Organs At Risk ◽

Left Lung ◽

Free Breathing ◽

Partial Mastectomy ◽

Breath Hold ◽

Deep Inspiration ◽

Deep Inspiration Breath Hold ◽

Dose Volume Histograms

Introduction: The purpose of this study was to compare the radiation dose to organs at risk for deep-inspiration breath hold (DIBH) and free-breathing (FB) radiotherapy in patients with lef-sided breast cancer undergoing adjuvant radiotherapy after partial mastectomy. Methods: One hundred patients with left-sided breast cancer underwent DIBH and FB planning computed tomography scans, and the 2 techniques were compared. Dose-volume histograms were analyzed for heart, left anterior descending coronary artery (LAD), and left lung. Results: Radiation dose to heart, LAD, and left lung was significantly lower for DIBH than for free breathing plans. The median mean heart dose for DIBH technique in comparison with FB was 1.21 Gy, and 3.22 Gy respectively; for LAD, 4.67 versus 24.71 Gy; and for left lung 8.32 Gy versus 9.99 Gy. Conclusion: DIBH is an effective technique to reduce cardiac and lung radiation exposure.

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