Differentiating basal-like and normal-like subtypes of triple negative breast cancer by using radiological analysis methods

Rugilė Mikalčiutė-Ramanauskienė1, Simona Rūta Letautienė1,2

1Vilnius University Faculty of Medicine

2National Cancer Institute

Abstract

Breast cancer is the most common malignancy among women. One of its most aggressive forms is considered to be triple negative breast carcinoma (TNBC), which can be divided into two subtypes: basal-like and normal-like. Invasive carcinoma is diagnosed in over 80% of TNBC cases. Nevertheless, subtypes have different prognosis and treatment options. Prognosis of the basal-like type is worse and treatment success rate depends on how early treatment is started. Immunohistochemistry is being used to differentiate these subtypes. While waiting for results of histological examination, radiological images can help differentiate subtypes faster: more time is left to make a proper treatment plan. The following characteristic differences were observed in the literature analysis. Most common basal-like tumour features: increased tumour mass, angular or spicular edges and no calcinates. And normal-like tomour features: smaller tumour mass, microlobular edges, lateral shadowing. Moreover, diagnostic sensitivity and specificity can be increased by using a combination of a mammogram and an ultrasound. Due to lack of data, MRI was not included in differential diagnsosis of normal-like and basal-like subtypes. However, knowing most common characteristics of these subtypes in mammograms and US can be helpful in differentiating TNBC subtypes more quickly, which can result in increased time for effective treatment planning.

Aim: To distinguish the most significant radiological features for the differential diagnosis of normal-like an cbasal-like subtypes of triple negative breast cancer.

Methods: International database such as Pubmed and ClinicalKey was used as the source of literature. We used keywords to find articles related to our topic. A total number of 130 articles were evaluated and repetitive and unrelated ones were removed, which resulted in almost 40 suitable articles being analysed and used.

Keywords: Triple negative breast cancer, ultrasound, mammogram.