Our study shows a declining rate of recurrence over the decades, suggesting that for a woman treated today, the expected recurrence rate should be lower than that seen in the randomized trials.
This study-“Recurrence rates for ductal carcinoma in situ: Analysis of 2,996 patients treated with breast-conserving surgery over 30 years”-shows that recurrence rates have significantly fallen over the decades, suggesting that the recurrence rates observed in the randomized studies are higher than what would be expected in the current era. Four large studies with mature follow-up (all began between 1985 and 1990) randomized women with ductal carcinoma in situ (DCIS) to radiation or not after they had breast-conserving surgery. Those studies are generally used to help women and clinicians estimate risk of subsequent recurrence in the same breast over time.
Our study shows a declining rate of recurrence over the decades, suggesting that for a woman treated today, the expected recurrence rate should be lower than that seen in the randomized trials. This is good news for women that want to have breast conservation for DCIS.
This population of women with DCIS is among the largest ever reported, so it allowed us to control for numerous other factors while examining the effect of the treatment period. Thus, our study could account for increased screening, wider margins, and increased use of radiation and endocrine therapy. And, even after accounting for many factors, there remained a lower risk of recurrence in women treated in more recent years.
I think that shared decision-making with the patient is the key to treating DCIS. Women with DCIS have several accepted treatment options, ranging from excision alone, excision with radiation, excision with endocrine therapy, excision with both radiation and endocrine therapy, to mastectomy and even bilateral mastectomy. Discussion of the pros and cons, risks and benefits of each option with each patient is necessary, so that their treatment can be aligned with their individual values.
Some women are very recurrence risk averse, and want to do everything to lower their risk of local recurrence, even if it means accepting some side effects. Others will accept a higher risk of recurrence and even invasive recurrence in order to avoid treatment that they fear. But what is essential is that a woman knows the expected benefit of each intervention for her, as well as the expected complications or side effects.
We have developed an online nomogram that estimates the risk of recurrence for an individual woman by using 10 different factors, including the use of radiation and endocrine therapy (the nomogram is available for free at nomograms.org). It can assist a woman and her clinician in individual decision-making regarding the various options, and help avoid over- and under-treatment by helping her weigh the pros and cons of each option.”
1. Van Zee KJ, Subhedar P, Olcese C, et al. Recurrence rates for ductal carcinoma in situ: Analysis of 2,996 patients treated with breast-conserving surgery over 30 years. 2015 American Society of Clinical Oncology (ASCO) Breast Cancer Symposium. Abstract 32.