Atypical breasts cancers

• Myoepithelial carcinomas comprise exclusively of tumour cells with myoepithelial differentiation and can be managed through surgical excision with radiotherapy.
• Mucinous carcinomas are difficult to diagnose but important to distinguish as survival rate between the types can vary.
• Invasive apocrine carcinomas are difficult to diagnose due to the variable presentation and lack of diagnostic criteria.

IntroductionWith increasing incidence of breast cancers there are now a larger number of cases diagnosed with rare malignancies. These can be diagnostic dilemmas and management strategy can be different by various breast multi-disciplinary teams (MDT).We aim to discuss the evidence-based approach for management of these atypical breast cancers which were identified in patients from a single breast screening unit.MethodPatient with unusual breast malignancies (all types except invasive ductal and lobular) treated under the care of a single surgeon were identified during the breast multi-disciplinary discussion from 2011 to 2015. The histology and management of these cases were reviewed and literature search of electronic databases via PubMed and the search engines Google/Google Scholar was performed. Emphasis on keywords based on the histology type was used to limit search. Search was focused on the diagnosis, management and prognosis of these unusual breast cancers.ConclusionThis series aims to focus on the evidence-based management of these rare breast malignancies; the diagnosis of which is crucial as it affects the overall treatment and prognosis.