In a nutshell
This study aimed to investigate the association between ipsilateral breast tumor recurrence (IBTR) and the timing of radiotherapy. This study found that a delay of more than 12 weeks in starting radiotherapy was associated with a higher risk of IBTR in women undergoing BCS for ductal carcinoma in situ.
Some background
Breast conserving surgery (BCS) followed by radiotherapy is a treatment option for ductal carcinoma in situ breast cancer. This combination has been shown to decrease the 10-year risk of IBTR of 15%. It is unclear if the timing of radiotherapy affects cancer recurrence rates.
Methods & findings
This study included information on 1323 women who had BCS followed by radiotherapy. Patients were followed for an average of 6.6 years, with 311 patients followed for more than 10 years. 61% of patients had radiotherapy less than 8 weeks after BCS (group 1). 29% of patients had radiotherapy between 8 and 12 weeks after BCS (group 2). 10% of patients underwent radiotherapy 12 weeks after BCS (group 3).
There were 126 instances of IBTR.
The 10-year recurrence rate was 13% for group 1, 7.6% for group 2, and 23% for group 3. Patients in group 3 had a 92% increased risk of IBTR compared to group 1.
Menopause and endocrine therapy had a protective effect against IBTR.
The bottom line
This study concluded that a delay of more than 12 weeks in starting radiotherapy was associated with a higher risk of IBTR in women undergoing BCS for ductal carcinoma in situ.
The fine print
This study is retrospective and so cannot determine the cause of associations, further studies may be necessary to get a clearer picture.
Published By :
Cancer
Date :
Sep 28, 2017
