Effect of Nodal Irradiation and Fraction Size on Cardiac and Cerebrovascular Mortality in Women With Breast Cancer Treated With Local and Locoregional Radiotherapy

Journal Article · Wed Jun 01 04:00:00 EDT 2011 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2010.02.041· OSTI ID:21491763

Tyldesley, Scott ^[1]; Woods, Ryan ^[2]; Wai, Elaine; Olivotto, Ivo A ^[1]

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1. Division of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, Vancouver, BC (Canada)
2. Population Oncology, British Columbia Cancer Agency, Vancouver, BC (Canada)

Purpose: To determine whether the adjuvant breast cancer radiation volume or fraction size (>2 Gy vs. {<=}2 Gy) affected the risk of fatal cardiac or cerebrovascular (CCV) events and to determine whether the addition of regional radiotherapy (RT) increased the risk of fatal cerebrovascular events compared with breast/chest wall RT alone. Methods and Materials: Overall survival was compared for patients receiving breast/chest wall RT alone or breast/chest wall plus regional node RT (BRCW+NRT) in a population-based cohort of women with early-stage breast cancer who had undergone RT between 1990 and 1996. The effect of laterality, age, systemic therapy, radiation volume, and fraction size on the risk of fatal CCV events was analyzed using a competing risk method. Results: A total of 4,929 women underwent adjuvant RT. The median follow-up was 11.7 years. BRCW+NRT was associated with an increased risk of CCV death at 12 years (5% for BRCW+NRT vs. 3.5% for breast/chest wall RT alone; p = .004), but the fraction size was not (3.92% for a fraction size >2 Gy vs. 3.54% for a fraction size <2 Gy; p = .83). The 12-year absolute risk of death from stroke alone did not differ for either radiation volume (1.17% for BRCW+NRT vs. 0.8% for breast/chest wall RT alone; p = .22) or fraction size (p = .59). Conclusion: Regional RT was associated with a small (1.5% at 12 years), but statistically significant, increased risk of death from a CCV event. The addition of regional RT did not significantly increase the risk of death from stroke, although the number of events was small. An increased fraction size was not significantly associated with a greater risk of fatal CCV events. These data support the continued use of hypofractionated adjuvant regional RT.

• OSTI ID: 21491763
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 80; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BODY
CHEST
DEATH
DISEASES
FRACTIONATED IRRADIATION
GLANDS
HAZARDS
HEALTH HAZARDS
IRRADIATION
MAMMARY GLANDS
MEDICINE
MORTALITY
NEOPLASMS
NUCLEAR MEDICINE
ORGANS
RADIATION HAZARDS
RADIOLOGY
RADIOTHERAPY
THERAPY
WALLS