40P - Molecular subtypes and imaging phenotypes of breast cancer: MRI

Background

This study aimed to examine MRI dynamic contrast-enhanced (DCE) imaging in various histological and molecular biological types of breast cancer.

Methods

To solve the set tasks, a clinical and instrumental examination was carried out of 70 women with a verified diagnosis of breast cancer who were examined and treated at the RSSPMCO&R in 2017–2019. The age of the patients was 26–75 years (mean age - 49.0 ± 2 years).

Results

For luminal A cancer (22 of 70 cases), the following MR signs were revealed: nodular formations more often had an irregular shape - 21 (95.5%), irregular (59.1%), less often spicular contours (27.3%). In 16 of 22 cases, a ring-shaped contrasting pattern was noted. Type III intensity-time curve at MRI with DCE was found in all 22 patients with luminal A subtype of breast cancer. It should be noted that all additional MR signs (retraction of the nipple, thickening and deformation of the skin over the formation) were found in luminal subtype A. The luminal B-subtype was detected in 20 patients (28.6%), with Her2/neu-positive luminal B-subtype noted in 12 patients, and Her2/neu-negative subtype in 8 cases. For these two subtypes of the masses visualized on MRI images were the same (irregular shape with indistinct contours, annular contrasting), but 4 of 12 patients with luminal Her2/neu-positive subtype had type II on MRI with DCE. The same type of curve was observed in 5 out of 11 patients (45.5%) with Her2/neu-positive breast cancer. At the same time, with luminal, subtype, luminal, Her2/neu-negative subtype, and three cases of negative breast cancer, type III of the dynamic contrast curve was always observed. Consequently, type II of the curve was observed only with negative Her2/neu types. In our studies, in 53% of triple-negative subtypes breast cancer was displayed on MR images with a rounded-oval or lobular shape, and in 17.6% with clear smooth (smooth) contours. But type III “intensity - time” curve, noted according to MRI data with DCE, testified to the malignant process in all 17 patients with triple-negative breast cancer.

Conclusions

Our studies have shown that the pathologically determined degree of differentiation of breast cancer and immunohistochemical types and subtypes affect the visualized morphological characteristics and its functional features, assessed by MRI with DCE.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Nishanova Yulduz.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.