Isolated ductal carcinoma in situ in patients presenting to two breast units in Johannesburg

Abstract

Background: Ductal carcinoma in situ (DCIS) represents approximately 20% of all new breast cancers in countries with population-based mammography screening. South Africa is an upper middle-income country with no such screening programmes in place, and the proportion of isolated DCIS appears much lower than this. Most patients present with symptomatic disease and high-risk features. There are numerous controversies regarding the diagnosis and optimal management strategy for this premalignant condition, and the issue of overtreatment is much debated. Our study aimed to determine the proportion of patients presenting with isolated DCIS, to describe the clinical presentation and to describe the treatment provided.
Methods: This is a retrospective cohort study of patients with histologically confirmed isolated DCIS at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital from July 2015 to March 2018. Records were collected from the existing clinical databases in both breast units and from the South African National Health Laboratory System.
Results: Out of 1 813 patients diagnosed and managed with breast malignancies in this period, 58 (3.1%) patients were identified with isolated DCIS. Forty-three (74.1%) of these patients were symptomatic. Thirty-four (58.6%) patients had a primary mastectomy, and 12 (20.6%) had breast-conserving surgery.
Conclusion: The diagnosis of isolated DCIS is rare in our setting, and the majority of patients present with more advanced, symptomatic disease that is not deemed suitable for breast-conserving surgery. The short-term follow-up of our patients has shown a low rate of recurrence and mortality thus far. However, further long-term follow-up is needed.