The management of women with ductal carcinoma in situ of the breast in Australia and New Zealand between 2007 and 2016

Abstract

Background: The incidence of detected ductal carcinoma in situ (DCIS) continues to increase and now accounts for 14% of all breast cancer, and 20%-25% of screen-detected cases. Treatment trends of DCIS are important in order to inform the ongoing debate about possible overdiagnosis and overtreatment, but have not been investigated for over a decade in Australia and New Zealand. Against this background, we aimed to describe the temporal trends in management of DCIS in Australian and New Zealander women.

Methods: Using the BreastSurgANZ Quality Audit (BQA) database, we conducted a descriptive study of the trends of management of DCIS in Australia and New Zealand from 2007 to 2016. We assessed the frequency of surgical treatments, adjuvant therapies, and axillary surgery conducted in women with pure DCIS.

Results: There were 17 883 cases of pure DCIS in 2007-2016 in Australia and New Zealand recorded in the BQA database. The treatment patterns were consistent with no changes over time. The most common surgical treatment was breast-conserving surgery (66%), followed by mastectomy (37%), and 36% of women with DCIS received sentinel node biopsy (SNB).

Conclusion: The clinical management of women diagnosed with DCIS in Australia and New Zealand, appears stable over time. A substantial proportion of women with DCIS receive SNB and this aspect of surgical care warrants further exploration to determine whether it represents appropriate care. These results, alongside the outcomes of the ongoing clinical trials on the management of DCIS, will help inform if any changes to best practice treatment are required.

Keywords: DCIS; breast; breast cancer; surgery; treatment.