A Retrospective Study To Compare Triple Negative Breast Cancer (TNBC) With 3 Subtypes Of Non Triple Negative Breast Cancer Using Dynamic Contrast Enhancement (DCE)-MRI And Diffusion Weighted Imaging (DWI)

AimThe aim of this study is to determine the MRI features of Triple Negative Breast Cancer (TNBC) [i.e. breast cancer which is estrogen receptor (ER) negative, progesterone receptor (PR) negative, and human epidermal growth factor receptor 2(HER2) negative] on Dynamic Contrast Enhancement (DCE)-MRI and Diffusion Weighted Imaging (DWI) in comparison with 3 subtypes of non triple negative breast cancer.Materials and MethodsThis research was approved by the hospital board committee of Affiliated Zhongshan Hospital of Dalian University and informed consent forms of patients were obtained. A total number of 141 female patients with breast cancer with age ranging from 24 years till 80 years were randomly chosen from May 2013 till September 2014. Among them,36 patients, with mean age 49.4±11.4 years, were pathologically confirmed Triple Negative Breast Cancer (TNBC) and 105 patients were 3 subtypes of non triple negative breast cancer. All MRI scans were done using standard 3T MRI scanner (SIEMENS, Verio, Germany). MR imaging findings include tumour shape, margin, size, intratumoral signal intensity on T2WI, Dynamic Contrast Enhancement (DCE) and mean Apparent Diffusion Coefficient (ADC) values of lesions were measured. Two experienced radiologists retrospectively assessed MRI features of the breast cancer patients. All statistical analyses were performed using SPSS version 16.0. Analysis of Variance (One Way ANOVA) test and Chi Square test were used to perform statistical calculations. A p value of<0.05 was considered statistically significant.ResultsCompared with the 3 subtypes of non triple negative breast cancer; 13 patients had oval shape mass (36%),22 patients had smooth margin mass (61%),22 patients had rim enhancement (61%) with mean size of mass 2.95±2.44 cm which was significantly large on DCE-MRI were all associated with TNBC.17 patients had high intratumoral signal intensity (47%) and 15 patients had very high intratumoral signal intensity (42%) on T2WI for TNBC. On DWI, mean ADC value (0.94×10-3mm2/s) of TNBC was higher than the mean ADC values of the 3 subtypes of non triple negative breast cancer, ER+/PR+/HER2 (0.78×10-3mm2/s); ER-/PR-/HER2+(0.83×10-3mm2/s); ER+/PR+/HER2+(0.79×10-3mm2/s) where p value was statistically significant (P< 0.05).ConclusionIt can be concluded that oval shape, smooth margin and large size mass with rim enhancement on DCE-MRI in addition with high and very high intratumoral signal intensity on T2 weighted imaging and high ADC values on DWI were all indicative MRI findings associated with TNBC. They can be useful to detect TNBC and an appropriate way to differentiate them with the 3 subtypes of non triple negative breast cancer.