In vivo assignment of methylmalonic acid in breast tissue using 2D MRS and relationship with breast density, menopausal status and cancer risk.

BACKGROUND: Methylmalonic acid (MMA) is linked to progression and aggressiveness of tumours. A recent study showed that high levels of circulatory MMA directed genetic programs promoting cancer progression. PURPOSE: To evaluate in vivo two-dimensional correlated spectroscopy (2D COSY) data from women at elevated risk of breast cancer to determine if resonances consistent with MMA are present, and if so to correlate levels with breast density, menopausal status and risk categories. MATERIALS AND METHODS: With institutional review board approval, 106 women at elevated risk (mean age 47), including 46 participants at medium risk, 43 at high risk with no known mutation and 17 BRCA-mutation carriers, were recruited. Breast density was assessed using a T2 sequence. A T1 sequence was used to place the voxel for the 2D COSY data. Peak volumes were normalized to the methylene peak at (1.30, 1.30) ppm. Chi-squared and Mann-Whitney tests were used. RESULTS: Two resonances are assigned on the diagonal at 3.15 ppm and 3.19 ppm consistent with and denoted MMA1 and MMA2 respectively. MMA1 and MMA2 increased in parallel with increased risk. BRCA-mutation carriers recorded an increase in mean MMA1 of 120% (p = 0.033) and MMA2 of 127% (p = 0.020) in comparison with participants with no known mutation. BRCA-mutation carriers with dense breasts recorded a significant increase in mean MMA1 of 137% (p = 0.002) and in mean MMA2 of 143% (p = 0.004) compared with BRCA-mutation participants with low-density breast tissue. MMA1 and MMA2 were higher in premenopausal women with dense breasts compared with those with low-density tissue. The highest values of MMA were recorded in BRCA-mutation carriers. CONCLUSION: Two tentative assignments are made for MMA in breast tissue of women at elevated risk for cancer. BRCA-mutation carriers exhibited higher values of MMA than those with no known mutation. Premenopausal women with BRCA mutation and dense breasts recorded the highest levels of MMA compared with other categories.

Mammographic features of benign breast lesions and risk of subsequent breast cancer in women attending breast cancer screening.

OBJECTIVES: To evaluate the mammographic features in women with benign breast disease (BBD) and the risk of subsequent breast cancer according to their mammographic findings. METHODS: We analyzed data from a Spanish cohort of women screened from 1995 to 2015 and followed up until December 2017 (median follow-up, 5.9 years). We included 10,650 women who had both histologically confirmed BBD and mammographic findings. We evaluated proliferative and nonproliferative BBD subtypes, and their mammographic features: architectural distortion, asymmetries, calcifications, masses, and multiple findings. The adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) for breast cancer were estimated using a Cox proportional hazards model. We plotted the adjusted cumulative incidence curves. RESULTS: Calcifications were more frequent in proliferative disease with atypia (43.9%) than without atypia (36.8%) or nonproliferative disease (22.2%; p value < 0.05). Masses were more frequent in nonproliferative lesions (59.1%) than in proliferative lesions without atypia (35.1%) or with atypia (30.0%; p value < 0.05). Multiple findings and architectural distortion were more likely in proliferative disease (16.1% and 4.7%) than in nonproliferative disease (12.8% and 1.9%). Subsequent breast cancer occurred in 268 (2.5%) women. Compared with women who had masses, the highest risk of subsequent breast cancer was found in those with architectural distortions (aHR, 2.21; 95% CI, 1.16-4.22), followed by those with multiple findings (aHR, 1.89; 95% CI, 1.34-2.66), asymmetries (aHR, 1.66; 95% CI, 0.84-3.28), and calcifications (aHR, 1.60; 95% CI, 1.21-2.12). CONCLUSION: BBD subtypes showed distinct mammographic findings. The risk of subsequent breast cancer was high in those who have shown architectural distortion, multiple findings, asymmetries, and calcifications than in women with masses. KEY POINTS: • The presence of mammographic findings in women attending breast cancer screening helps clinicians to assess women with benign breast disease (BBD). • Calcifications were frequent in BBDs with atypia, which are the ones with a high breast cancer risk, while masses were common in low-risk BBDs. • The excess risk of subsequent breast cancer in women with BBD was higher in those who showed architectural distortion compared to those with masses.

Breast density, benign breast disease, and risk of breast cancer over time.

OBJECTIVES: Assessing the combined effect of mammographic density and benign breast disease is of utmost importance to design personalized screening strategies. METHODS: We analyzed individual-level data from 294,943 women aged 50-69 years with at least one mammographic screening participation in any of four areas of the Spanish Breast Cancer Screening Program from 1995 to 2015, and followed up until 2017. We used partly conditional Cox models to assess the association between benign breast disease, breast density, and the risk of breast cancer. RESULTS: During a median follow-up of 8.0 years, 3697 (1.25%) women had a breast cancer diagnosis and 5941 (2.01%) had a benign breast disease. More than half of screened women had scattered fibroglandular density (55.0%). The risk of breast cancer independently increased with the presence of benign breast disease and with the increase in breast density (p for interaction = 0.84). Women with benign breast disease and extremely dense breasts had a threefold elevated risk of breast cancer compared with those with scattered fibroglandular density and without benign breast disease (hazard ratio [HR] = 3.07; 95%CI = 2.01-4.68). Heterogeneous density and benign breast disease was associated with nearly a 2.5 elevated risk (HR = 2.48; 95%CI = 1.66-3.70). Those with extremely dense breast without a benign breast disease had a 2.27 increased risk (95%CI = 2.07-2.49). CONCLUSIONS: Women with benign breast disease had an elevated risk for over 15 years independently of their breast density category. Women with benign breast disease and dense breasts are at high risk for future breast cancer. KEY POINTS: • Benign breast disease and breast density were independently associated with breast cancer. • Women with benign breast disease had an elevated risk for up to 15 years independently of their mammographic density category.

Ultrasound Findings of Breast Adenomas.

OBJECTIVES: Breast adenomas are rare benign tumors. The aim of this study was to describe the ultrasound findings of breast adenomas, including less common worrisome features that can mimic malignancy. METHODS: From November 2014 to November 2019, we performed 1605 core needle biopsies guided by ultrasound in our department. In all, 229 corresponded to fibroadenomas and 12 to breast adenomas. RESULTS: Breast adenomas represented 0.75% of all core needle biopsies; 50% (6 of 12) were tubular adenomas; 17% (2 of 12) were ductal adenomas; and 33% (4 of 12) were lactating adenomas. Tubular and lactating adenomas occurred in young women and ductal adenomas in postmenopausal women. Lactating adenomas occurred in pregnant or breastfeeding women and were larger than the other adenomas. Ultrasound showed a mass with an oval shape, a parallel orientation, circumscribed margins, and hypoechoic and homogeneous patterns in most cases. However, up to one-third of them presented with suspicious findings. CONCLUSIONS: Breast adenomas are rare benign entities with no specific clinical and radiologic features. Sometimes, they appear as suspicious tumors on radiologic modalities, requiring a histopathologic assessment to rule out malignancy. Radiologists need to be familiar with this entity to determine concordance between imaging and the final pathologic analysis.

Neoadjuvant Systemic Therapy in Breast Cancer: Association of Contrast-enhanced MR Imaging Findings, Diffusion-weighted Imaging Findings, and Tumor Subtype with Tumor Response.

Purpose To investigate the performance of tumor subtype and various magnetic resonance (MR) imaging parameters in the assessment of tumor response to neoadjuvant systemic therapy (NST) in patients with breast cancer and to outline a model of pathologic response, considering pathologic complete response (pCR) as the complete absence of any residual invasive cancer or ductal carcinoma in situ (DCIS). Materials and Methods This was an institutional review board-approved retrospective study, with waiver of the need to obtain informed consent. From November 2009 to December 2014, 111 patients with histopathologically confirmed invasive breast cancer who were undergoing NST were included (mean age, 54 years; range, 27-84 years). Breast MR imaging was performed before and after treatment. Presence of late enhancement was assessed. Apparent diffusion coefficients (ADCs) were obtained by using two different methods. ADC ratio (mean posttreatment ADC/mean pretreatment ADC) was calculated. pCR was defined as absence of any residual invasive cancer or DCIS. Multivariate regression analysis and receiver operating characteristic analysis were performed. Results According to their immunohistochemical (IHC) profile, tumors were classified as human epidermal growth factor receptor 2 (HER2) positive (n = 51), estrogen receptor (ER) positive/HER2 negative (n = 40), and triple negative (n = 20). pCR was achieved in 19% (21 of 111) of cases; 86% of them were triple-negative or HER2-positive subtypes. Absence of late enhancement at posttreatment MR imaging was significantly associated with pCR (area under the curve [AUC], 0.85). Mean ADC ratio significantly increased when pCR was achieved (P < .001). A κ value of 0.479 was found for late enhancement (P < .001), and the intraclass correlation coefficient for ADCs was 0.788 (P < .001). Good correlation of ADCs obtained with the single-value method and those obtained with the mean-value methods was observed. The model combining the IHC subtype, ADC ratio, and late enhancement had the highest association with pathologic response, achieving an AUC of 0.92 (95% confidence interval: 0.86, 0.97). Conclusion Triple-negative or HER2-positive tumors showing absence of late enhancement and high ADC ratio after NST are associated with pCR. © RSNA, 2016 Online supplemental material is available for this article.

Amyloidosis of the Breast: Three Different and Unusual Presentations of a Rare Entity.

BACKGROUND: Amyloidosis involving the breast is a rare finding and it may present as a solitary mass called 'amyloid tumor'. According to the largest case series, the amyloid deposits are usually of the AL type (commonly x03BA; light chain). METHODS: We report 3 cases diagnosed at our institution in the period from 2000 to 2015. Radiological, histological and immunohistochemical studies were performed. RESULTS AND CONCLUSIONS: Together with a case presenting in a patient with multiple myeloma, we describe 2 unique presentations including 1 associated with CREST syndrome in a patient with a previous history of breast carcinoma and another, also associated with cancer, with transthyretin deposits in a woman with a TTR gene mutation and a family history of familial amyloidotic polyneuropathy. These cases are an example of the vast heterogeneity of this disorder regarding its clinical presentation, the type of amyloid deposits and other diseases associated with breast amyloidosis.

Role of computer-aided detection in very small screening detected invasive breast cancers.

This study aims to assess computer-aided detection (CAD) performance with full-field digital mammography (FFDM) in very small (equal to or less than 1 cm) invasive breast cancers. Sixty-eight invasive breast cancers less than or equal to 1 cm were retrospectively studied. All cases were detected with FFDM in women aged 49-69 years from our breast cancer screening program. Radiological characteristics of lesions following BI-RADS descriptors were recorded and compared with CAD sensitivity. Age, size, BI-RADS classification, breast density type, histological type of the neoplasm, and role of the CAD were also assessed. Per-study specificity and mass false-positive rate were determined by using 100 normal consecutive studies. Thirty-seven (54.4 %) masses, 17 (25 %) calcifications, 6 (8.8 %) masses with calcifications, 7 (10.3 %) architectural distortions, and 1 asymmetry (1.5 %) were found. CAD showed an overall sensitivity of 86.7 % (masses, 86.5 %; calcifications, 100 %; masses with calcifications, 100 %; and architectural distortion, 57.14 %), CAD failed to detect 9 out of 68 cases: 5 of 37 masses, 3 of 7 architectural distortions, and 1 of 1 asymmetry. Fifteen out of 37 masses were hyperdense, and all of them were detected by CAD. No association was seen among mass morphology or margins and detectability. Per-study specificity and CAD false-positive rate was 26 % and 1.76 false marks per study. In conclusion, CAD shows a high sensitivity and a low specificity. Lesion size, histology, and breast density do not influence sensitivity. Mammographic features, mass density, and thickness of the spicules in architectural distortions do influence.

Analysis of Local Recurrence Risk in Ductal Carcinoma In Situ and External Validation of the Memorial Sloan Kettering Cancer Center Nomogram.

BACKGROUND: Adjuvant radiotherapy and hormonotherapy after breast-conserving surgery (BCS) in ductal carcinoma in situ (DCIS) have been shown to reduce the risk of local recurrence. To predict the risk of ipsilateral breast tumor relapse (IBTR) after BCS, the Memorial Sloan Kettering Cancer Center (MSKCC) developed a nomogram to analyze local recurrence (LR) risk in our cohort and to assess its external validation. METHODS: A historical cohort study using data from 296 patients treated for DCIS at the Hospital Clínic of Barcelona was carried out. Patients who had had a mastectomy were excluded from the analysis. RESULTS: The mean age was 58 years (42-75), and the median follow-up time was 10.64 years. The overall local relapse rate was 13.04% (27 patients) during the study period. Actuarial 5- and 10-year IBTR rates were 5.8 and 12.9%, respectively. The external validation of the MSKCC nomogram was performed using a multivariate logistic regression analysis on a total of 207 patients, which did not reach statistical significance in the studied population for predicting LR (p = 0.10). The expression of estrogen receptors was significantly associated with a decreased risk of LR (OR: 0.25; p = 0.004). CONCLUSIONS: In our series, the LR rate was 13.4%, which was in accordance with the published series. The MSKCC nomogram did not accurately predict the IBTR in this Spanish cohort of patients treated for DCIS (p = 0.10).

Quantitative ultrasound image analysis of axillary lymph nodes to differentiate malignancy from reactive benign changes due to COVID-19 vaccination.

PURPOSE: The aim of this study is to assess the potential of quantitative image analysis and machine learning techniques to differentiate between malignant lymph nodes and benign lymph nodes affected by reactive changes due to COVID-19 vaccination. METHOD: In this institutional review board-approved retrospective study, we improved our previously published artificial intelligence model, by retraining it with newly collected images and testing its performance on images containing benign lymph nodes affected by COVID-19 vaccination. All the images were acquired and selected by specialized breast-imaging radiologists and the nature of each node (benign or malignant) was assessed through a strict clinical protocol using ultrasound-guided biopsies. RESULTS: A total of 180 new images from 154 different patients were recruited: 71 images (10 cases and 61 controls) were used to retrain the old model and 109 images (36 cases and 73 controls) were used to evaluate its performance. The achieved accuracy of the proposed method was 92.7% with 77.8% sensitivity and 100% specificity at the optimal cut-off point. In comparison, the visual node inspection made by radiologists from ultrasound images reached 69.7% accuracy with 41.7% sensitivity and 83.6% specificity. CONCLUSIONS: The results obtained in this study show the potential of the proposed techniques to differentiate between malignant lymph nodes and benign nodes affected by reactive changes due to COVID-19 vaccination. These techniques could be useful to non-invasively diagnose lymph node status in patients with suspicious reactive nodes, although larger multicenter studies are needed to confirm and validate the results.

Magnetic Resonance Imaging Assessment of Radial Scars/complex Sclerosing Lesions of the Breast.

PURPOSE: To describe the magnetic resonance characteristics of radial scars/complex sclerosing lesions (RS/CSL) of the breast using the current BI-RADS lexicon. To investigate the value of diffusion weighted imaging to predict malignancy. PATIENTS AND METHODS: From 2010 to 2017, we have found 25 women with architectural distortion at mammography who underwent surgical resection with a final hystopathologic report of RS/CSL. For the description of MRI findings, we adhered to BI-RADS classification (5th edition). RESULTS: The final pathological diagnosis was: "pure" RS/CSL in 7 cases (28%), RS/CSL with associated high risk lesions in 12 (48%) and 6 cases (24%) were associated with malignancy. Magnetic resonance findings: four of 25 negative or focus. Five of 25 mass enhancement: irregular, non circumscribed spiculated mass with heterogeneous or rim enhancement and most with type II curves. Sixteen of 25 non mass enhancement: focal or linear distribution and heterogeneous internal enhancement most with type I curves. Six of 25 had cancer associated with the complex sclerosing lesion. All six showed non-mass enhancement. Two cases with invasive breast carcinoma had ADC values under 1.15 x10-3 mm/s while most of the rest had the values above. CONCLUSION: Most RS/CSL showed enhancement at MR. The predominant pattern was a non-mass, focal, heterogeneous internal enhancement with type 1 curves. All cases with associated cancer showed non mass enhancement. Invasive breast cancers had ADC values < 1.15 10-3 s/mm2.

Long-Term Risk of Breast Cancer after Diagnosis of Benign Breast Disease by Screening Mammography.

Assessing the long-term risk of breast cancer after diagnosis of benign breast disease by mammography is of utmost importance to design personalised screening strategies. We analysed individual-level data from 778,306 women aged 50-69 years with at least one mammographic screening participation in any of ten breast cancer screening centers in Spain from 1996 to 2015, and followed-up until 2017. We used Poisson regression to compare the rates of incident breast cancer among women with and without benign breast disease. During a median follow-up of 7.6 years, 11,708 (1.5%) women had an incident of breast cancer and 17,827 (2.3%) had a benign breast disease. The risk of breast cancer was 1.77 times higher among women with benign breast disease than among those without (95% CI: 1.61 to 1.95). The relative risk increased to 1.99 among women followed for less than four years, and remained elevated for two decades, with relative risk 1.96 (95% CI: 1.32 to 2.92) for those followed from 12 to 20 years. Benign breast disease is a long-term risk factor for breast cancer. Women with benign breast disease could benefit from closer surveillance and personalized screening strategies.

Risk of breast cancer two years after a benign biopsy depends on the mammographic feature prompting recall.

OBJECTIVE: We aimed to explore whether the type of mammographic feature prompting a false-positive recall (FPR) during mammography screening influences the risk and timing of breast cancer diagnosis, particularly if assessed with invasive procedures. STUDY DESIGN: We included information on women screened and recalled for further assessment in Spain between 1994 and 2015, with follow-up until 2017, categorizing FPRs by the assessment (noninvasive or invasive) and mammographic feature prompting the recall. MAIN OUTCOME MEASURES: Breast cancer rates in the first two years after FPR (first period) and after two years (second period). RESULTS: The study included 99,825 women with FPRs. In both periods, the breast cancer rate was higher in the invasive assessment group than in the noninvasive group (first period 12 ‰ vs 1.9 ‰, p < 0.001; second period 4.4‰ vs 3.1‰, p < 0.001). During the first period, the invasive assessment group showed diverse breast cancer rates for each type of mammographic feature, with a higher rate for asymmetric density (31.9‰). When the second period was compared with the first, the breast cancer rate decreased in the invasive assessment group (from 12‰ to 4.4‰, p < 0.001) and increased in the noninvasive assessment group (from 1.9‰ to 3.1‰, p < 0.001). CONCLUSION: In the context of mammography screening, the risk of breast cancer diagnosis during the first two years after FPR was particularly high for women undergoing invasive assessment; importantly, the risk was modified by type of mammographic feature prompting the recall. This information could help to individualize follow-up after exclusion of malignancy.

Radiologic and pathologic findings in breast tumors with high signal intensity on T2-weighted MR images.

Various histopathologic components in benign and malignant breast lesions may generate hyperintense signal at T2-weighted magnetic resonance (MR) imaging. A comparison of the specific histologic features found in breast lesions with a high-signal-intensity appearance on unenhanced T2-weighted turbo spin-echo MR images obtained without spectral fat suppression shows that this MR imaging characteristic is often suggestive of the differential diagnosis. Histopathologic features that may produce high signal intensity in breast lesions include extensive necrosis, a cystic or microcystic component, an adipose or sebaceous component, mucinous stroma, loose myxoid stroma, stromal edema, and hemorrhagic changes. A more nuanced understanding of the correlation between the MR imaging appearance and specific pathologic findings may help radiologists achieve earlier and more accurate differentiation among this group of breast lesions.

Ultrasound-anatomic correlation of the peripheral nerves of the upper limb.

BACKGROUND: Sonography allows good visualization of the peripheral nerves and the vascular and muscular structures that surround them. Our goals are to provide an easy-to-use atlas that gives accurate information about the locations and relations among the nerves in the different parts of the arm and to correlate it with the probe position and the ultrasound images. MATERIALS AND METHODS: A cadaver right arm was used for the present study. The arterial and venous vessels were injected with red and blue-colored latex to obtain a better correlation with ultrasound slices from two healthy volunteers. The specimen was frozen and then cut into slices with an average thickness of 2 cm, starting from the lower part of the axilla. RESULTS: Close correlation was present between the ultrasound and anatomic slices identifying the main muscular, vascular and nervous structures. In the arm, median, ulnar and radial nerves were easily seen because of the proximity to vascular landmark and their size. In the forearm, the ulnar nerve was also easy to identify because of the factors previously mentioned; the median nerve was easy to locate between the flexor digitorum superficialis and profundus muscles. The superficial branch of the radial arm was seen in most cases, although some skill was required. CONCLUSION: Ultrasound is a useful tool to identify the main nerves of the upper arm. This atlas indicates the locations and relations among the nerves, correlating with the ultrasound appearance.

[Influence of diagnostic pathway on clinical and non-conventional therapies use in women with breast cancer of the cohort DAMA]. / Influencia de la vía diagnóstica en la clínica y el uso de terapias no convencionales en mujeres con cáncer de mama de la cohorte DAMA.

OBJECTIVE: To describe and analyze the characteristics of breast cancer tumours according to the diagnostic pathway. We analyse the adverse effects of the treatments and the use of unconventional therapies in order to alleviate them. METHOD: Descriptive design nested in a mixed cohort (Cohort DAMA). The dependent variable was the route to diagnosis of breast cancer. The independent variables were age, body mass index, social class, disposable family income, type of tumour, histological degree, tumour stage, recurrences, treatment, adverse effects derived from treatments and unconventional therapies. Bivariate descriptive analyses were performed and univariate and multivariate regression models were adjusted; and graphic representations of the unconventional therapies. RESULTS: There are differences in the characteristics of the tumours, and the impact of the adverse effects derived from the treatments. The patients diagnosed by screening were older, from a high social class, had a higher percentage of tumours of grade I differentiation, initial stages, fewer recurrences and fewer adverse effects due to treatment, although this was not different in the screening group compared to the rest. There was also less use of unconventional therapies. CONCLUSIONS: The results indicate that the implementation of screening programmes increases the possibility of detecting tumours in initial stages and with therapies with fewer adverse effects. As a result, there is less need to resort to unconventional therapies.

Differences in breast cancer risk after benign breast disease by type of screening diagnosis.

INTRODUCTION: We aimed to assess differences in breast cancer risk across benign breast disease diagnosed at prevalent or incident screens. MATERIALS AND METHODS: We conducted a retrospective cohort study with data from 629,087 women participating in a long-standing population-based breast cancer screening program in Spain. Each benign breast disease was classified as non-proliferative, proliferative without atypia, or proliferative with atypia, and whether it was diagnosed in a prevalent or incident screen. We used partly conditional Cox hazard regression to estimate the adjusted hazard ratios of the risk of breast cancer. RESULTS: Compared with women without benign breast disease, the risk of breast cancer was significantly higher (p-value = 0.005) in women with benign breast disease diagnosed in an incident screen (aHR, 2.67; 95%CI: 2.24-3.19) than in those with benign breast disease diagnosed in a prevalent screen (aHR, 1.87; 95%CI: 1.57-2.24). The highest risk was found in women with a proliferative benign breast disease with atypia (aHR, 4.35; 95%CI: 2.09-9.08, and 3.35; 95%CI: 1.51-7.40 for those diagnosed at incident and prevalent screens, respectively), while the lowest was found in women with non-proliferative benign breast disease (aHR, 2.39; 95%CI: 1.95-2.93, and 1.63; 95%CI: 1.32-2.02 for those diagnosed at incident and prevalent screens, respectively). CONCLUSION: Our study showed that the risk of breast cancer conferred by a benign breast disease differed according to type of screen (prevalent or incident). To our knowledge, this is the first study to analyse the impact of the screening type on benign breast disease prognosis.

The influence of arm abduction on the anatomic relations of infraclavicular brachial plexus: an ultrasound study.

BACKGROUND: Distances from brachial plexus to the coracoid process and the pleura are critical for performing infraclavicular block. We evaluated the influence of arm abduction on the position of the neurovascular bundle relative to the skin, to the coracoid process and to the pleura using ultrasonography. METHODS: An ultrasound examination of the brachial plexus at the infraclavicular level was performed on 26 patients. Distances from the axillary artery to the skin, to the coracoid process and to the pleura were measured and noted with different degrees of arm abduction (0 degrees , 45 degrees , and 90 degrees ). Vertical infraclavicular brachial plexus block was then performed by means of nerve stimulation in 14 additional patients undergoing hand surgery. RESULTS: Under ultrasound examination, the distance from the axillary artery to the skin was found to be significantly less with arm abduction (0 degrees : 32 +/- 7 mm, 45 degrees : 29 +/- 7 mm, 90 degrees : 25 +/- 5 mm, P < 0.05). The distance from the skin to the pleura was 47 +/- 5 mm with a medial deviation of 18 +/- 3 degrees and was not influenced by arm position. Brachial plexus was identified by nerve stimulation at a vertical depth of 41 +/- 7 mm from the skin. CONCLUSION: Abduction of the arm reduces the depth of the brachial plexus but does not change the position of the axillary artery relative to the coracoid process or the pleura. Ultrasonography may under-estimate the actual depth of the plexus.

Quantitative Ultrasound Image Analysis of Axillary Lymph Nodes to Diagnose Metastatic Involvement in Breast Cancer.

This study aimed to assess the potential of state-of-the-art ultrasound analysis techniques to non-invasively diagnose axillary lymph nodes involvement in breast cancer. After exclusion criteria, 105 patients were selected from two different hospitals. The 118 lymph node ultrasound images taken from these patients were divided into 53 cases and 65 controls, which made up the study series. The clinical outcome of each node was verified by ultrasound-guided fine needle aspiration, core needle biopsy or surgical biopsy. The achieved accuracy of the proposed method was 86.4%, with 84.9% sensitivity and 87.7% specificity. When tested on breast cancer patients only, the proposed method improved the accuracy of the sonographic assessment of axillary lymph nodes performed by expert radiologists by 9% (87.0% vs 77.9%). In conclusion, the results demonstrate the potential of ultrasound image analysis to detect the microstructural and compositional changes that occur in lymph nodes because of metastatic involvement.