Long-term cardiovascular mortality after radiotherapy for breast cancer.
OBJECTIVE
This study sought to investigate long-term cardiovascular mortality and its relationship to the use of radiotherapy for breast cancer.


BACKGROUND
Cardiovascular diseases are among the main long-term complications of radiotherapy, but knowledge is limited regarding long-term risks because published studies have, on average, <20 years of follow-up.


METHODS
A total of 4,456 women who survived at least 5 years after treatment of a breast cancer at the Institut Gustave Roussy between 1954 and 1984 were followed up for mortality until the end of 2003, for over 28 years on average.


RESULTS
A total of 421 deaths due to cardiovascular diseases were observed, of which 236 were due to cardiac disease. Women who had received radiotherapy had a 1.76-fold (95% confidence interval [CI]: 1.34 to 2.31) higher risk of dying of cardiac disease and a 1.33-fold (95% CI: 0.99 to 1.80) higher risk of dying of vascular disease than those who had not received radiotherapy. Among women who had received radiotherapy, those who had been treated for a left-sided breast cancer had a 1.56-fold (95% CI: 1.27 to 1.90) higher risk of dying of cardiac disease than those treated for a right-sided breast cancer. This relative risk increased with time since the breast cancer diagnosis (p = 0.05).


CONCLUSIONS
This study confirmed that radiotherapy, as delivered until the mid-1980s, increased the long-term risk of dying of cardiovascular diseases. The long-term risk of dying of cardiac disease is a particular concern for women treated for a left-sided breast cancer with contemporary tangential breast or chest wall radiotherapy. This risk may increase with a longer follow-up, even after 20 years following radiotherapy.
Radiation Epidemiology Group-CESP-Unit 1018 INSERM, Villejuif, France.
Kim
K
Bouillon
Nadia
N
Haddy
Suzette
S
Delaloge
Jean-Remy
JR
Garbay
Jerome-Philippe
JP
Garsi
Pauline
P
Brindel
Abdeddahir
A
Mousannif
Monique G
MG
Lê
Martine
M
Labbe
Rodrigo
R
Arriagada
Eric
E
Jougla
Jean
J
Chavaudra
Ibrahima
I
Diallo
Carole
C
Rubino
Florent
F
de Vathaire
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy*; D002173:Cancer Care Facilities; D002318:Cardiovascular Diseases / Q000209:etiology* / Q000401:mortality*; D002423:Cause of Death; D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006321:Heart / Q000528:radiation effects*; D006801:Humans; D015412:Mastectomy, Segmental / Q000379:methods; D008875:Middle Aged; D011832:Radiation Injuries / Q000401:mortality; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D013997:Time Factors