**4. Breast ultrasound lexicon**

Descriptors for breast tissue composition (background echotexture) are correlated to mammographic breast densities. These are homogeneous-fat, homogenousfibroglandular, and heterogeneous. In Homogeneous-fat background, fat lobules and echogenic bands of supporting structures comprise the bulk of the breast tissue. In the Homogeneous-fibroglandular background, a dense zone of the homogeneously echogenic bands of fibroglandular parenchyma is present beneath the thin hypoechogenic layer of fat lobules. Heterogeneous background echotexture is characterized by multiple small areas of increased or decreased echogenicity, either focal or diffuse.

For the identification and characterization of the masses, the number of characteristics to be described are seven: *shape* (oval, round, and irregular), *orientation* (parallel and not parallel), *margins* (circumscribed and not circumscribed, indistinct, angular, microlobulated, and spiculated), *echo pattern* (anechoic, hyperechoic, complex cystic and solid, hypoechoic, isoechoic and heterogeneous) *posterior acoustic features* (no posterior acoustic features, enhancement, shadowing and combined pattern), *calcifications* (in or outside of a mass, and intraductal) and *associated features*.

Associated features include architectural distortion; edema; duct changes; skin changes (skin retraction, skin thickening-focal and diffuse-); vascularity (absent, internal, and vessel in rim), and elasticity assessment. Elasticity assessment of tissue stiffness (elastography) explores modifications of the US image of a lesion after applying a manual compression (strain) or introducing ultrasonic energy (shear wave). Applicable descriptors are color-codes tissue hardness. The elasticity assessment is a feature available on many modern US units and included in the last BI-RADS edition. The World Federation of Ultrasound in Medicine and Biology (WFUMB) has published guidelines in characterizing breast lesions as benign or malignant, although this fact cannot be misinterpreted as an entire endorsement of the clinical validity of elasticity assessment. Therefore, the elastography should be integrated for patient management alongside the more predictive ultrasonic morphologic features of malignancy (shape, margin, and echogenicity). Currently, the share-wave elastography is used as a valuable preoperative predictor of chemotherapy response [16].

It is essential to analyze several features, rather than just one, for lesion categorization as benign or malignant. Benign and malignant solid masses can equally be well-differentiated on ultrasound. Benign US features include an oval shape, wellcircumscribed margins, and parallel orientation to the skin. Suspicious US features include irregular margins, marked hypoechogenicity, post-acoustic shadowing, and non-parallel orientation to the skin (**Figure 1**).

### **Figure 1.**

*Ultrasound characteristics of breast lesions. (a) Circumscribed, oval, anechoic mass with parallel orientation and posterior enhancement consistent with a simple cyst. (b) Circumscribed, round, heterogeneous mass with lateral shadowing. The pathological diagnosis by biopsy was Fibroadenoma. (c) Irregular, noncircumscribed, hypoechoic mass with posterior shadowing: Invasive Breast Carcinoma by biopsy.*

### **5. Identification and characterization of palpable breast symptoms**

### **5.1 Nipple discharge**

Clinical workup of nipple discharge includes a detailed patient medical history, recently recorded trauma, careful physical examination, and the most suitable breast imaging modality. The evaluation and management aim of nipple discharge is to identify the causative condition accurately, distinguishing between "pathologic" causes from those with "benign or physiological" causes, and consequently diagnosing cancer when it is present.

The discharge's clinical characteristics should describe color, whether uni or bilateral or associated with nipple stimulation or breast compression, whether it originated from a single duct or multiple ducts [17]. Benign nipple discharge is traditionally considered bilateral, non-spontaneous, emanating from multiple ducts

### *Value of Breast Ultrasound in the Clinical Practice of the Surgeon DOI: http://dx.doi.org/10.5772/intechopen.100520*

after manipulation or stimulation; varies in color from white to yellow to green to brown. Pathologic discharge is considered unilateral, spontaneous, persistent, clear, serous, serosanguinous, or bloody from a single duct [18].

Breast imaging identifies and characterizes any lesion in these patients and assists subsequent percutaneous biopsy in achieving a histopathologic diagnosis [19]. Magnetic resonance imaging (MRI) may be useful in pathologic nipple discharge when lesions cannot be localized with other diagnostic imaging [20]. However, MRI is limited, and it is not yet a generalized practice because it is expensive and not readily available in all areas [21].

In patients with nipple discharge, the sensitivity of mammography in detecting an abnormality is low. The ability of mammograms to identify intraductal lesions is limited since they are generally small and lack microcalcifications. In mammography subareolar region usually shows increased density. The sensitivity and specificity of ultrasound vary from 36 to 83% and 12–84%, respectively. Several factors can explain this wide range, including differences in the criteria used to distinguish between pathologic from benign discharge and differences in ultrasound technology employed [22]. Breast US is useful for visualizing ductal structures, localization of the lesions that cause the nipple discharge, and the subsequent accomplishment of imaging-guided percutaneous biopsy to determine whether a malignant lesion is the cause of the pathologic nipple discharge. US-guided core needle biopsy in patients with pathologic nipple discharge, who had negative findings on mammography but had positive findings on US have reported 15.1% of cancer detection [23].

Breast US is capable of visualizing ductal structures located in the subareolar region. The BI-RADS® categorizes ductal changes as *associated features*. Duct changes are manifested by:


### **Figure 2.**

*(a) Single galactophere duct ectasia without any filling defect (calipers); (b) 49-year-old female with uniorificial serous nipple discharge. US: duct ectasia with echogenic content filled with thick secretion; (c) 46-year-old female with uniorificial bloody nipple discharge. US: single dilated duct with isoechoic endoductal mass with an ill-defined outline representing an intraductal papilloma by pathology report; (d) 39-year-old female with right uniorifical serosanguineous discharge. US: irregular intraductal mass arising from a dilated duct due to carcinoma in situ.*

At present, there are no clear guidelines on which radiographic or clinical variables in patients with nipple discharge can predict malignancy. The malignancy rate in patients with nipple discharge ranges from 9.3–23% [18, 25–29]. However, these data were derived from studies made before improvements in breast ultrasound and the imaging-guided percutaneous biopsy. Most studies included patients referred to surgery departments or specialty breast centers [18, 25–27] or only those who underwent duct excision [28, 29].

Currently, less invasive diagnostic procedures affect the decision-making process about surgical management. For patients with pathological discharge and negative imaging evaluation (negative mammography results and negative features on breast US), surgical treatment has traditionally been indicated to eliminate symptoms and rule out breast carcinoma [24–28]. Although based on the low risk of underlying carcinoma, several studies have proposed conservative clinical follow-up and have shown that short-term monitoring would appear to be a reasonable approach in these patients [30, 31] Sabel et al. [31] suggested short-term observation with repeat imaging and clinical exam for low-risk patients (those without a strong family history or personal history of cancer). Ashfaq et al. [30] proposed a close clinical follow-up comprising a physical examination and breast ultrasound every six months for 1 to 2 years, or until the discharge resolved, whichever came first, plus annual mammography according to the screening guidelines. Patients who refuse to watch and wait as a clinical approach or report discomfort by the symptom or discharge after two years should consider the surgical treatment (**Figure 3**).

**Figure 3.** *Workflow for the management of women presenting with nipple discharge.*

### **5.2 Inflammatory breast disease**

Ultrasound examination is essential in evaluating patients with breast inflammation to identify fluid collections in the affected area by the inflammatory

process and distinguish between cancer-related and non-cancer-related breast inflammation (since their clinical presentation can be misleading). Inflammatory breast disease manifests clinically by the cardinal signs of inflammation: redness, heat, and pain. It is classified as an infectious origin (generally bacterial) or noninfectious origin.

Breast US cardinal signs of infectious inflammatory breast disease are [32]:


Ultrasound can be used to guide percutaneous sampling procedures and complete drainage of the fluid collection. If the collection is large (sizes >3 cm)- or if it remains or recurs-placing a percutaneous drainage catheter guided by US is the optimal course of the management [34]. In the unusual event of inadequate percutaneous drainage, surgical drainage should be an option.

Non-infectious inflammatory breast disease includes Granulomatous Mastitis and Diabetic Mastopathy. Diabetic Mastopathy appears as a hypoechoic mass with ill-defined margins and marked posterior shadowing.

Granulomatous Mastitis is a diagnosis of exclusion, and it is hardly made based on clinical signs and imaging findings. Clinical presentation is a firm to hard mass localized or diffused involvement of the entire breast with skin thickening, erythema, and inflammation (peau d' orange) that can clinically mimic carcinoma. In addition, the presence of draining sinus tracts and regional adenopathy are frequent. The diagnosis is established by histological analysis showing a granulomatous inflammatory response containing multinucleated giant cell granuloma. It is mainly seen in developing countries [35, 36]. Breast US signs in granulomatous mastitis are:

• Skin thickening


### **Figure 4.**

*45-year-old female with redness, heat, and pain in the right breast. US: (a) Hypoechoic mass with heterogeneous content, poorly defined borders, and acoustic shadowing. Thickening of the dermal layer. Fat hyperechogenicity around the mass. (b) Image using Doppler signal reveals increased surrounding vascularization. (c) US-Guided Percutaneous Biopsy: Granulomatous Mastitis.*

## **5.3 Mass in breast skin**

Lesions in the breast skin that arise within the dermal layer are considered generally benign. Most dermal lesions are palpable, providing the reason for imaging evaluations. Although occasionally, they are detected at screening imaging. This lesion includes dermal cysts, specifically sebaceous cysts and epidermal inclusion cysts (after a mammoplasty), for which routine surveillance is recommended..

Ultrasound findings of dermal lesions are [37]:


**Figure 5.**

*57-year-old female with epidermal inclusion cyst located on the breast skin after mammoplasty. US: (a) hypoechoic well-circumscribed mass contained within the dermis. The dermal layer is thickened (white arrow) and extended into the hypodermis. A tract extends to the epidermal skin surface (red arrow). (b) The claw sign (white dashed line): dermal tissue wrapping around the margin of the lesion forming an acute angle.*
