**6. Evaluation and characterization of abnormals associated with implants**

In addition to the clinical examination, ultrasound is a useful diagnostic test to examine breast implant alterations, mainly ruptures. The breast implant is anechoic with an echogenic shell of a three-layered appearance (an anechogenic line between two echogenic lines). Small radial folds and a small amount of periprosthetic fluid are considered normal findings. US is very specific in evaluating breast implant integrity, albeit not very sensitive. The probability of rupture is highly suspected in US, but a rupture is still possible, even if it cannot be visible in US [7].

Alterations of the implant structure, classically, are *capsular contracture* or *capsular fibrosis* and *ruptures*. Capsular contracture is the capsule developed around the implant as the body's overreaction to a foreign device, leading to the hardening and deformation of the implant. There are three typical findings for capsular contracture or fibrosis: (1) *deformity*, not well evaluable with ultrasound (due to the narrow field of view), (2) *increased number of radial folds,* creating an undulated implant surface; and (3) *thickening of the fibrous capsule*, an echogenic line superficial to the implant shell, separated only by an anechoic line [38].

*Ruptures* are subdivided into intracapsular (implant envelope is broken, but containment remains inside the capsule) and extracapsular (when containment leaks out of the broken capsule) type [39]. The classic finding of extracapsular rupture of silicone implant on US is the snowstorm appearance, i.e., a highly echogenic pattern of scattered and reverberating echoes with a well-defined anterior margin. This appearance can also see in the axillary nodes containing free silicone. Intracapsular silicone implant rupture finding is the stepladder sign, characterized as a sequence of horizontal echogenic straight or curvilinear lines inside the collapsed implant shell [40]. If the prosthesis is saline, the collapsed implant shell will be evident by ultrasound.

According to the American College of Radiologists [41], breast implants evaluation varies on patient age, implant type, and symptoms. For patients less than 30 years with rupture of saline implants, ultrasound is the imaging choice. Mammography or US may be used for patients from 30 to 39 years of age with rupture of saline implants, and mammography is preferred for those 40 years and older. MRI without contrast or US is preferred for patients less than 30 years with

rupture of silicone implants. MRI without contrast, mammography, or US may be used for those 30 to 39 years of age, and for those 40 years and older, MRI without contrast or mammography is used. Patients with unexplained axillary lymphadenopathy and silicone implants (current or previous) are assessed with the axillary US. Patients with suspected breast implant-associated anaplastic large-cell lymphoma should be recommended breast US, regardless of age or implant type.

### **7. Guidance for percutaneous and interventional procedures**

Interventional breast procedures are guided by the clinical examination or image-detected nonpalpable breast abnormalities to characterize the lesion histologically and plan therapeutic management [11]. Clinical guidance may be sufficient in palpable lesions, but image-guided biopsy allows more precise acquisition with high diagnostic accuracy. Ultrasound-guided procedures are accessible without needing ionizing radiation or intravenous contrast but are rather minimally invasive and less expensive than surgical biopsies [42].

Training and accreditation of surgeon-performed US are essential steps for increasing the use of percutaneous biopsy to diagnose breast pathologies, avoiding additional surgeries and diagnostic delays, particularly in resource constraint settings. Breast surgeons, who perform the percutaneous biopsy, must understand its indications, have technical skills for performing them, and be experienced operators to avoid misleading and harmful procedures, resulting in missed cancer. They should record complications and adverse events during ultrasound-guided interventional procedures and regularly review them to recognize circumstances and opportunities to improve patient management quality. In the same way, surgeons should monitor false-negative rates and inadequate tissue samples of these interventional procedures to audit their practice [9].

US-Guided interventional procedures include fine-needle aspiration cytology (PAAF), core needle biopsy (CNB), vacuum-assisted needle biopsy, placement of brachytherapy devices, and breast tissue ablation.

### **7.1 US-guided fine-needle aspiration cytology (US-FNAC)**

FNAC uses a disposable needle (usually 18 to 27- gauge) connected to a vacuum syringe. It is technically simple, widely available, and easy to plan in outpatient clinics. It can be performed with a low risk of complications. It is an accurate technique and affordable in resource constraints settings [43]. Quality depends on the aspirator's competence and the pathologist's proficiency and expertise in determining its interpretation. FNAC is more appropriate for patients on anticoagulants for lesions adjacent to the skin, close to the chest wall or close to vessels, or patients with implants, or with very small lesions and those with small/thin breasts [44].

Ultrasound-guided needle aspiration puncture is mainly recommended for the aspiration of simple symptomatic cysts. If the aspiration fluid is clear, yellow, greenish-black (no atypical features), it can be discarded and not require further evaluation [45]. In case that the fluid is bloody, it must be sent for cytological analysis. If it looked purulent, it must be sent for culture and gram stain. If suspicious, atypical, or mucin results are found in cytology, re-biopsy or excision of the lesion should be performed. The patient should accomplish a follow-up ultrasound in 4 to 6 weeks when the cyst has been completely evacuated. Whether the cyst recurs, the re-biopsy of the lesion is mandatory [46].

Although core needle biopsy is currently advocated as the standard procedure in most breast centers in developed countries, FNAC continues to be an acceptable *Value of Breast Ultrasound in the Clinical Practice of the Surgeon DOI: http://dx.doi.org/10.5772/intechopen.100520*

and reliable procedure for diagnosing suspicious breast lesions in low and middleincome countries. Two meta-analyses assessed the accuracy performance of FNAC [46, 47]. The meta-analysis of Yu et al. [48] included 46 studies showing pooled sensitivity of 92.7% and specificity of 94.8%; however, the pooled sensitivity and specificity for eleven studies that reported unsatisfactory samples was 92.0% and 76.8%, respectively. The meta-analysis by Wang et al., [47] compared the sensitivity and specificity of CNB and FNAC in twelve studies; the pooled analysis showed that the sensitivity of CNB is better than that of FNAC (87% vs. 74%). However, the specificity of CNB was similar to that of FNAC (98% vs. 96%).

### **7.2 Ultrasound-guided core needle biopsy (CB)**

Ultrasound-Guided Core Needle Biopsy involves 14G–16G spring-loaded automated needles with an excursion throw that allows small cylinders of tissue (specimen) to be cut and collected within the notch of the needle. The needle is extracted from the breast to recover the breast tissue and then re-inserted for further samples. False-negative rates range from 0% [49] to 9% [50], and underestimation rates range from 3.4–100% in atypical ductal hyperplasia, radial scars, papillary lesions, lobular carcinoma in situ (LCIS), and phyllodes tumors [51].

### **7.3 US vacuum-assisted biopsy (VAB)**

VAB is commanded with suction and a rotating cutter. This device uses needles ranging from 7 G to 12 G. Vacuum aspiration pulls lesion tissue samples for collection into a sampling window without removing the needle from the biopsy site [50]. VAB is commanded with suction and a rotating cutter. This device uses needles ranging from 7 G to 12 G.

Currently, there is an increasing interest in using US-guided vacuum-assisted devices for the complete removal of a probably benign lesion [52, 53], with low rates of residual masses, particularly for lesions <1 cm in size [54]. Additionally, successful excision of intraductal masses has been reported in women with nipple discharge [55].

### **7.4 Guided ablative techniques**

Tumor destruction techniques are by heat (hyperthermia) or by cold (cryotherapy) means. Several technologies using hyperthermia are available: radiofrequency, microwaves, interstitial laser, and electroporation [42]. The percutaneous radiofrequency device utilizes five small radiofrequency-enabled wires deploy from the wand (capture basket) to circumscribe the lesion. Radiofrequency passes through the expanded basket, sectioning and coagulating the breast tissue. The device can remove entire lesions up to 25–30 mm [56].

Cryotherapy involves the use of argon gas to generate an ice sphere around the lesion. Ultrasound is used in real-time to visualize the growth of the ice ball around the lesion; this is an outpatient procedure that can be performed under local anesthesia [2].

### **7.5 Indications for excisional biopsy**

Currently, the percutaneous imaging-guided biopsy is the standard for the diagnosis of most breast lesions. However, there are still indications when excisional surgical biopsy should be recommended. The acquaintance of such indications is essential to adopt the multidisciplinary approach and provide the best patient care.

Adequate radiology/histology/clinical correlation is essential, in addition to the cautious post-biopsy surveillance for immediate detection of false-negative results, to prevent delays in cancer diagnosis. Clinical situations where open excisional biopsy should be recommended include [57]:


## **8. Preoperative evaluation of the breast in diagnosed breast cancer**

The tumor size obtained by imaging is an important factor in the preoperative planning of breast cancer, whether it is the type of surgery or whether it initiates with neoadjuvant chemotherapy (NAC). Thus, mammography has been considered the standard imaging tool for detecting and assessing tumor size. Currently, the high-resolution US and MRI have been included in the diagnostic flowchart to achieve higher sensitivity [56], underscoring the surgeons' need to know the accuracy of each test to attain affordable breast cancer patient care.

Several studies [57–68] assess mammography, US, and MRI accuracy for measuring preoperative tumor size in patients who do not receive neoadjuvant chemotherapy. These studies showed correlations between ultrasonographic tumor size and pathologic tumor size ranging from 0.40 to 0.93, suggesting that breast ultrasound accurately predicts tumor size for those patients.

Although many studies have evaluated the value of preoperative magnetic resonance imaging (MRI) in invasive breast cancer, its role in clinical practice is still controversial, failing to show surgical outcome benefits [69–71]. A meta-analysis by Houssami and colleagues [69], which included 3,112 patients with breast cancer, found a significant increase in mastectomy rates in the MRI group (16.4% and 25.5%, respectively) with the non-MRI group (8.1% and 18.2%, respectively). This meta-analysis failed to show a surgical outcome benefit because there was no difference in re-excision rate following an initial breast-conservation, with 11.6% in the MRI group compared with 11.4% non-MRI group (P = .87). The authors suggest that a routine MRI in breast cancer patients could do more harm than good by identifying foci of disease beyond the lumpectomy bed that would have been eradicated by adjuvant radiation. Two prospective randomized trials [70, 71] assessed the effect of MRI on surgical outcomes in patients with breast cancer, with a primary end-point of reoperation rates (re-excision and conversion to mastectomy). The United Kingdom (UK) randomized trial (COMICE) [70] evaluated the

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

role of breast MRI in 1,625 women who had recently been diagnosed with primary breast malignancy. The trial showed no significant difference in the reoperation rate between the MRI group (18.7%) and the non-MRI group (19.3%). A twenty-eight percent increase in mastectomy rates was considered pathologically avoidable in the MRI group. The MONET trial [71] randomized 418 women with a nonpalpable suspicious mammographic or sonographic finding (BIRADS 3 to BIRADS 5 lesion) to receive preoperative MR Imaging versus usual care (mammography and ultrasound followed by biopsy). One hundred sixty-three women were diagnosed with breast cancer. There was a paradoxical increase in the re-excision rate in the MRI group (34%) and no difference in conversion to mastectomy (11%) compared with the re-excision rate in the non-MRI group (12%, P = .008) and conversion to mastectomy (14% *P* = .49).

### **9. Preoperative evaluation of axilla in diagnosed breast cancer**

Ultrasound is the primary imaging technique to evaluate morphological abnormalities in the lymph nodes. It is a moderately sensitive method (between 26 and 80%) and can be very specific (ranges from 88 to 98%) [72, 73] when a morphological sign that indicates alterations is used as a diagnostic criterion such as general shape, the aspect of the cortex, the hilum and vascularization, rather than size [72–74]. A normal axillary lymph node sizes less than 10 mm, has a smooth and welldefined contour with an echogenic hilum (constitutes the majority of the node), and is surrounded by a thin and uniform hypoechoic cortex measuring less than 3 mm [75]. The ultrasound aspects of tumor infiltration in a crescent order of specificity are diffuse cortical thickening (> 3 mm); focal cortical bulge; eccentric cortical thickening; rounded hypoechoic node; partial or complete effacement of the fatty hilum; non-hilar blood flow on color Doppler; partial or total replacement of the node with an ill-defined (or irregular mass) and microcalcifications in the node [76]. The last step of the tumoral infiltration is spread to the perinodal fat [74, 76–78].

Axillary Ultrasound (AUS) and needle biopsy of abnormal-appearing nodes can appropriately allocate a positive predictive value for detecting nodal metastases [79, 80]. The use of ultrasound and biopsy in an abnormal lymph node improves sensitivity (88% vs. 61%), specificity (100% versus 85%), positive predictive value (91% versus 73%), and negative predictive value (100% versus 77%) compared to US alone [73–75]. The approach for identifying axillary metastases in women with T1 or T2 invasive breast cancer ranges from axillary imaging only in patients with suspicious findings (from physical examination of the axilla) [74] to axillary imaging being performed in all patients [5–7]. The identification of axillary disease on preoperative ultrasound was considered a reliable indicator for preoperative identification of axillary metastases, allowing the surgeon to proceed directly to axillary lymph node dissection (ALND) and omission of sentinel lymph nodes biopsy (SNB) [81].

However, the clinical utility of preoperative axillary imaging evaluation in women with T1 or T2 invasive breast cancer has changed with the American College of Surgeons Oncology Group (ACOSOG) Z0011 study [82] and International Breast Cancer Study Group (IBCSG)23–01 [83]. These randomized controlled trials have established that women with clinical T1–2 invasive breast carcinoma and clinically negative axilla with 1–2 positive sentinel lymph nodes (SLNs) can safely spare ALND without impacting overall survival, disease-free survival, or locoregional recurrence. Hence, several studies have attempted to evaluate whether it can manage patients without palpable adenopathy but with positive axillary nodes identified by ultrasound according to Z0011 criteria [84–87]. These studies have reported that between 43% and 51.9% of patients with nodal metastases on imaging had

pN1 disease at surgery, suggesting that a cohort of patients with axillary metastases detected by imaging alone can be candidates for the omission of ALND based on minimal nodal disease. Although a considerable percentage of patients with imagedetected positive nodes have pN1 disease, multiple abnormal lymph nodes on axillary imaging were associated with a high likelihood of having pN2–3 disease and worse survival [88–90]. Axillary ultrasound seems to be more suited to exclude high axillary burden than quantifying the nodal disease volume in the event of abnormal axillary lymph nodes detected on preoperative axillary imaging.

In patients with clinically abnormal lymph nodes on physical exam, further evaluation of axilla with AUS with/without needle biopsy should consider appropriating to neoadjuvant chemotherapy, given the high nodal pathologic completed response (PCR) rates of 21 to 65% [91, 92]. Studies support the use of SNB for surgical staging of the axilla with false-negative rates of 8.4 to 14.2% [93–95]. Consequently, the de-escalation of axillary surgery for patients with metastatic axilla may not eliminate the need for the axillary US, but it certainly may make its use more selective.
