Management and 5-year outcomes in 9938 women with screen-detected ductal carcinoma in situ: the UK Sloane Project

TLDR: Recurrent DCIS or invasive cancer is uncommon after screen-detected DCIS and both RT and endocrine therapy were associated with a reduction in further events but not with breast cancer mortality within 5 years of diagnosis.

About: This article is published in European Journal of Cancer.The article was published on 2018-08-06 and is currently open access. It has received 46 citations till now. The article focuses on the topics: Breast cancer & Breast-conserving surgery.

Figures

Figure 1: 9938 UK patients with screen-detected DCIS (2003-2012).

Figure 3: Survival from the date of recurrence

Figure 2: Radiotherapy (RT) and ipsilateral breast events.

Table 1: Radiotherapy (RT) use & pathological features after breast conservation surgery (BCS).

Frequently asked questions

Q1. What was the effect of RT on ipsilateral recurrence?

Adjuvant endocrine therapy (1208/9938; 12%) was associated with a reduction in any ipsilateral recurrence, whether RT was received (HR 0.57: 95% CI 0.41 - 0.80) or not (HR 0.68: 95% CI 0.51 - 0.91) after BCS. 

Q2. What was the risk of a breast recurrence after BCS?

Ipsilateral breast recurrence after BCS was 5.3% (368/7007); ipsilateral chest wall recurrence after mastectomy was 0.8% (24/2931). 

Q3. What was the effect of RT on breast recurrence?

Endocrine therapy was associated with a non-significant reduction in ipsilateral breast recurrence independent of RT, although the greatest effect was seen for the reduction of invasive further events in the absence of RT. 

Q4. What were the requirements for participating units?

Participating units were required to follow a pathology protocol containing definitions for DCIS, microinvasion, cytonuclear grade, comedo necrosis and assessment of excision margins and to handle and report specimens to NHSBSP pathology standards. [8] 

Q5. How many women are invited to breast screening every three years?

The United Kingdom National Health Service Breast Screening Programme (NHSBSP) invites women aged 50-70 to attend breast screening every three years (supplementary figure and text p2). 

Q6. What was the association of RT with breast recurrence?

mastectomy was, not unexpectedly, associated with features of more aggressive DCIS.RT following BCS was associated with a significant reduction in all ipsilateral breast further events (DCIS or invasive) at a median follow up of 64 months. 

Q7. What is the impact of digital mammography on breast cancer?

12]The increasing incidence of DCIS, likely to be sustained with the enhanced visualisation that digital mammography provides, now deployed in the UK NHS BSP, emphasises the potential for overtreatment of women diagnosed though breast screening. [1] 

Q8. What was the requirement for participating radiologists to complete a radiology proforma?

Radiology guidelines mandated participating radiologists should complete detailed radiology proformas [9] and participate in the NHSBSP PERFORMS external quality assurance scheme. [10] 

Q9. What was the association between mastectomy and breast cancer?

The use of mastectomy was associated with DCIS of high or intermediate rather than low grade (p<0.001) and with larger lesion size (p<0.001).