Radiation Increases Breast Cancer Risk in Young Women
Risk of contralateral cancer higher after radiation and with family history
WEDNESDAY, Oct. 15 (HealthDay News) -- Women with breast cancer have a higher risk of developing cancer in the opposite breast if they were younger when initially treated, received radiation using tangential fields and have a family history of breast cancer, according to study findings published online Oct. 14 in the Journal of Clinical Oncology.
Maartje J. Hooning, M.D., from the Netherlands Cancer Institute in Amsterdam, and colleagues examined the long-term risk of contralateral breast cancer in 7,221 women with breast cancer after chemotherapy and radiotherapy.
The researchers found that the risk was higher in women who were younger at first treatment (hazard ratio 1.78 for women under 35 years old, hazard ratio 1.09 for women older than 45 years old). Women under 45 years old who were treated with postlumpectomy radiotherapy (using tangential fields) rather than postmastectomy radiotherapy (using direct electron fields) had a 1.5-fold higher risk of contralateral breast cancer. Women who had both postlumpectomy radiotherapy and a strong family history of breast cancer had a higher than expected risk (hazard ratio 3.52), the investigators found. Adjuvant chemotherapy was associated with a lower risk of contralateral breast cancer only during the first five years of follow-up, the authors report.
"Young patients with breast cancer irradiated with breast tangentials experience increased risk of contralateral breast cancer, especially in those with a positive family history of breast cancer," Hooning and colleagues conclude. "This finding should be taken into account when advising breast radiation with tangential fields to young patients with breast cancer."