Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females worldwide [17]. The incidence of breast cancer in Egypt is 32.04% [18]. According to the WHO (World Health Organization), the incidence is 30% and mortality from breast cancer had increased recently in the younger women, so the main issue lies in the screening and early tumor detection to ensure an effective management and better prognosis [19].
Early detection of breast cancer and accurate assessment of lesions are the goals of various imaging modalities to ensure an effective management and better prognosis [20].
The response of breast cancer to therapy is influenced by many factors as tumor type, tumor grade, and the state of biological markers [10], so the aim of this study was to find association between ultrasound findings and tumor type, grade, and the state of biological markers.
In this study, when correlating the US descriptors with the tumor type, we found that the shape and the margin of the mass were the most important US descriptors to differentiate between invasive breast cancer and DCIS (p value < 0.001) with irregular shape, and speculated margin was more frequently seen in invasive cancer (90.4% and 100%, respectively), while most cases of DCIS were characterized by oval/rounded shape and smooth margins (71.4% and 57.1%, respectively) (Fig. 5). This is in agreement with the study done by Marino et al. [8], and they performed a study on 49 breast cancer patients and reported that irregular shape (78.6%) and non-circumscribed margins (100%) were more frequent in invasive cancer than DCIS (p value < 0.005). Our results are also comparable with the study done by An et al. [9]. They performed a study on 52 breast cancer patients and concluded that irregular shape (75.3%) and non-circumscribed margins (61.8%) were more frequent in invasive cancer than DCIS (p value = 0.001).
Our results reported that there was no statistically significant difference in posterior feature descriptor in differentiating between invasive cancers and DCIS (p value = 0.427), and these results are concordant with the study done by Kim et al. [10], who stated that there was no statistical significant difference in posterior features between invasive cancers and DCIS (p value = 0.4552).
We concluded that the other US descriptors (orientation and echopattern) cannot differentiate between invasive cancers and DCIS (p value = 0.604 and 1.000, respectively). This is in agreement with the study done by Scoggins et al. [11], who reported that there was no statistically significant difference in orientation and echopattern in differentiating between invasive cancer and DCIS (p value = 1.000 and 0.543, respectively). They reported that irregular shape, non-circumscribed margin, and no posterior features were the most important descriptors in differentiation between tumor types.
Out of the 13 cases of DCIS included in this study, 6 cases were non-mass forming malignancies (parenchymal distortion); in another way, all malignant cases assessed as NMLs were DCIS. Our results are comparable with the study done by Lee et al. [12]. They noted that NMLs were more frequently related with malignancies such as ductal carcinoma in situ (DCIS).
The association between tumor grade of invasive cancer and US findings in previous studies was varied. Watermann et al [13] reported that tumor grading did not significantly influence US descriptors characteristics; on the other hand, Lamb et al. [14] found that high-grade invasive cancer were more likely to demonstrate posterior acoustic enhancement and well-defined margins. Further studies [10, 15] observed that non-circumscribed margin and hypoechoic or heterogeneous echo patterns were more frequent in grade 3 than in grade 1 and 2 invasive cancers. In our study, we observed no statistical significant difference between low (Fig. 4)/medium (Fig. 1) and high-grade (Fig. 2) tumor type as regards the examined US descriptors (shape, margin, orientation, posterior feature, and echopattern) (p values 1.0, 0, 0.544, 1.0, and 1.0, respectively). It is likely that the difference between all the previous studies including our results is reliant on the microstructure of the tumors, and this needs further studies.
In this study, we also correlated the US descriptors in breast cancer cases with the biological markers (estrogen, progesterone, HER-2/neu2, and KI 67). As regards the association between the US descriptors and the state of estrogen receptors, we found that irregular shape (88%) was the most important descriptor in estrogen-positive breast cancers (p value = 0.036). Our results reported that there were no statistically significant difference as regard mass margin (p value = 0.494). Our result are comparable with An et al. [9], who reported that irregular shape had a statistically significant difference (p value = 0.005) while there was no statistically significant difference as regards mass margin, posterior features, and echopattern in ER-positive cases (p value 0.83, 1.00, and 0.534, respectively). Our results are in agreement with the study done by Costantini et al. [15], who reported that antiparallel orientation was more frequent in ER-positive breast cancers 41 (82.0%) but with no statistically significant difference. Our results are in disagreement with the study done by Kim et al. [10], who reported that hypoechoic/complex echopattern, shadowing/combined posterior features, and anti-parallel orientation have statistically significant association in ER-positive cases (p value 0.0033, 0.0566, and 0.0190, respectively).
As regards the association between the US descriptors with the state of progesterone receptors, we found that irregular shape and non-circumscribed margins were the most important descriptor in PR-positive breast cancers (p value = 0.026 and 0.068, respectively) respectively. This is in agreement with Moon et al. [21], who reported that irregular shape is frequently associated with progesterone receptor-positive cases (p value = 0.005) and Costantini et al. [15], who reported that non-circumscribed speculated margins are more frequently associated with progesterone positivity (p value = 0.009). In our study, there were no statistically significant difference in other US descriptor (orientation, echopattern, and posterior features) when correlated with the state of progesterone receptors (p value = 0.713, 0.526, and 1.000, respectively).
As regards the US correlation with the HER-2/neu oncogene expression, we found that there were no statistically significant difference between US descriptors (shape, margin, orientation, echopattern, and posterior features) and HER-2/neu state (p value 0.510, 0.639, 0.299, 0.898, and 1.000, respectively). This is in agreement with Kim et al. [10], who reported that there were no statistically significant difference between us descriptors (shape, margin, orientation, echopattern, and posterior feature) and HER-2/neu state (p value = 0.2521, 0.8243, 0.5334, 0.7620, and 0.2242, respectively). This also was in agreement with Cho et al. [16], who reported that there were no statistically significant difference as regards US descriptors (shape, margin, and orientation) and HER-2/neu state (p value = 0.173, 0.99, and 0.201, respectively).
As regards the US correlation with the ki67-positive breast cancer cases, we found that irregular shape and non-circumscribed margin are more frequent with ki76-positive cases with statistically significant difference (p value = 0.050 and 0.047, respectively). We concluded that there were no statistical significant association between ki76-positive breast cancers and US descriptors (echopattern and posterior feature) (p value = 1.000 and 0.248, respectively). Our results are comparable with Costantini et al. [15]. They concluded that echopattern and posterior features did not attain the level of statistical significance (p value 0.248 and 1.000, respectively).