Outcomes for Women with Minimal-Volume Ductal Carcinoma In Situ Completely Excised at Core Biopsy

Abstract

Introduction Overdiagnosis and overtreatment of ductal carcinoma in situ (DCIS) are concerns, especially in women with low-volume screen-detected DCIS. We sought to evaluate outcomes in such patients. Methods Women with minimal-volume DCIS (mDCIS, defined as diagnosed with DCIS by core biopsy but no residual disease on surgical excision) treated with breast-conserving surgery from 1990–2011 were identified. Ipsilateral and contralateral breast events (IBE and CBE) were compared by competing-risk (CR) analysis. Kaplan-Meier (KM) estimates and log-rank tests were used to evaluate covariates. Results 290 cases of mDCIS were identified; median age was 53yrs. 27.6% received radiation (RT); 16.2% received endocrine therapy. Median follow-up was 6.8 yrs. Overall, 5- and 10-yr IBE rates were 4.3% and 12.3%. Among women not receiving RT, 5- and 10-yr IBE rates (5.4% and 14.5%) were higher than CBE rates (1.8% and 2.7%); among those receiving RT, IBE rates (1.5% and 6.0%) were lower than CBE rates (4.1% and 15.6%). Women receiving RT trended toward significantly lower IBE rates (p=0.07); age, grade and endocrine therapy were not significantly associated with IBE risk. Conclusions Among patients with mDCIS not receiving RT, IBE risk was substantially higher than CBE risk, demonstrating that even DCIS of very low volume is associated with clinically relevant disease. The finding that IBE risk is greater than CBE risk supports current strategies that treat DCIS as a precursor rather than a risk marker. Women with mDCIS are not at negligible risk of IBE in the absence of adjuvant therapy.

Validation of a Ductal Carcinoma In Situ Biomarker Profile for Risk of Recurrence after Breast-Conserving Surgery with and without Radiotherapy

“…The incorporation of the protein biomarkers and the four DS clinicopathologic factors in the DCISionRT algorithm allowed for further risk stratification of patients with traditionally low-risk clinicopathology factors, as 50% of these patients had elevated categorical DS (Table 4). This observation is consistent with prior studies showing that some BCS-treated patients with smaller size or lower grade DCIS tumors still had substantial 10-year recurrence in the DS elevated risk group (4,28). Thus, use of categorical DS may lead to more refined risk estimates than clinicopathology alone.…”

A prediction model for underestimation of invasive breast cancer after a biopsy diagnosis of ductal carcinoma in situ: based on 2892 biopsies and 589 invasive cancers

“…To our knowledge, this information has never been demonstrated before; one study demonstrated a similar rate of minimal-volume DCIS, but the association with underestimation was not investigated. 31 In our study, the minimal-volume DCIS was higher for the predicted low-risk group.…”

“…A rate of 9.3% was reported. 31 Second, of the underestimated invasive breast cancers the information on unfavourable features is of interest; the reported Her2Neu status is quite high 22,23 and the hormonal receptor statuses vary [21][22][23]25,26 .…”

Behaviour and characteristics of low‐grade ductal carcinoma in situ of the breast: literature review and single‐centre retrospective series

“…Among tumours larger than 20 mm, Pinder and colleagues reported that low‐/intermediate‐ and high‐grade DCIS had a lower risk of ipsilateral recurrence (DCIS or invasive) compared to very high‐grade DCIS (defined as high‐grade DCIS + >50% solid architecture + >50% ducts with comedo necrosis), although the results were not statistically significant ( P = 0.09). However, it is interesting to note that a recent study by Muhsen et al . documented 5‐ and 10‐year ipsilateral breast recurrence rates of 4.3 and 12.3% for low‐volume screen‐detected DCIS that had been completely excised at core biopsy, showing that even very small‐sized DCIS may have the potential for recurrence.…”