Optical tomography with ultrasound localization: initial clinical results and technical challenges

Optical tomography with ultrasound localization utilizes co-registered ultrasound lesion structure information to guide optical imaging reconstruction. A hand-held probe consisting of a commercial ultrasound transducer and near infrared optical imaging sensors was used to simultaneously acquire ultrasound images and optical measurements. A dual-mesh scheme was used to map the ultrasound-visible lesions to finer-grid lesion regions and coarser-grid background regions for optical imaging reconstruction. As a result, optical imaging reconstruction was well-conditioned for inverse mapping of lesion hemoglobin concentration and blood oxygen saturation. Initial clinical results have shown that early stage invasive cancers may be distinguished by a two-fold greater total hemoglobin concentration compared with fibroadenomas and other benign lesions. Initial results of advanced cancers have shown that the hemoglobin distribution is highly distorted and heterogeneous and the distorted distributions correlate with histological microvessel density counts and could be used to assess chemotherapy response.     

Utilizing optical tomography with ultrasound localization to image heterogeneous hemoglobin distribution in large breast cancers

PURPOSE: Angiogenesis in advanced breast cancers is highly distorted and heterogeneous. Noninvasive imaging that can monitor angiogenesis may be invaluable initially for diagnosis and then for assessing tumor response to treatment. By combining ultrasound (US) and near-infrared (NIR) optical imaging, a reliable new technique has emerged for localizing and characterizing tumor angiogenesis within the breast. METHODS: This new technique employs a commercial US transducer coupled with an array of NIR optical fibers mounted on a hand-held probe. The US image is used for lesion localization and for guiding optical imaging reconstruction. Optical sensors are used for imaging tumor total hemoglobin distribution, which is directly related to tumor angiogenesis. RESULTS: Six large breast carcinomas were studied and microvessel density count was then performed on tissue samples obtained from these cancers. Two patients had locally advanced breast cancers and received neoadjuvant chemotherapy for 3 months. In one patient, before chemotherapy, the total hemoglobin distribution showed a high concentration at the cancer periphery; the distribution was later confined to the core area after 3 months of treatment. In another patient, as treatment progressed, the maximum hemoglobin concentration decreased from 255.3, to 147.5, to 76.9 micromol/l with an associated reduction in spatial extension. The other four patients had cancers of 2.0 to 3.0 cm in size and were imaged either at the time of core biopsy or definitive surgery. The histologic microvessel density counts from these tumor samples correlate to hemoglobin distributions with a correlation coefficient of 0.64 (P < .05). CONCLUSION: These initial results suggest that this new imaging technique may have great potential in imaging the heterogeneous vascular distribution of larger breast cancers in vivo and in monitoring treatment-related changes in angiogenesis during chemotherapy.     

Value of ultrasound and magnetic resonance imaging in the preoperative evaluation of suspected ovarian masses

BACKGROUND: The stage of ovarian carcinoma at diagnosis directly affects prognosis. Thus, thorough pretreatment evaluation is basic to the successful management of suspected ovarian masses. Among currently available imaging techniques in characterization of suspected ovarian neoplasms, sonography (US) is indisputedly the primary imaging approach. When US is inconclusive, magnetic resonance imaging (MRI) is generally prefered to computed tomography (CT). MATERIALS AND METHODS: 93 patients, who on the basis of clinical findings were suspected to have ovarian cancer and who were scheduled for subsequent surgical staging underwent preoperative transvaginal and abdominal ultrasound as well as magnetic resonance imaging in a prospective comparative study. US and MR images were evaluated for their information on the characterization and staging of the ovarian masses. RESULTS: MRI correctly characterized malignant and benign tumors in 89% of cases versus 85% by ultrasound. The site of the primary tumor was correctly diagnosed in 94% of cases by MRI vs. 90% by ultrasound. For US, the positive predictive value was 85%, the negative predictive value 73% vs. 92% and 89% for MRI. In differentiation of nonadvanced disease from advanced malignancy, US showed a false-positive rate of 0.416 and false-negative rate of 0.258 vs. 0.125 and 0.032 respectively, for MRI. CONCLUSION: MRI was superior in diagnosis of malignant ovarian masses though US, too, performed well at lesion detection and characterization. With regard to tumor staging MRI is emerging as a problem-solving modality and may allow more appropriate clinical decisions to be made in selected patients with complex adnexal disease.     

Reducing lesion aberration by dual-frequency focused ultrasound ablations

Discrepancies between hyperecho-predicted necrosed volume in ultrasound (US) images and the actual size of a thermal lesion might cause incomplete ablation or damage normal structures during high intensity focused US (HIFU) ablations. A novel dual-frequency sonication procedure is proposed to reduce this discrepancy. HIFU transducers of either 1 or 3.5?MHz were applied to transparent tissue-mimicking phantoms and ex vivo bovine liver samples. A diagnostic probe and a charge-coupled device (CCD) camera were used to record lesion formation in real time, allowing for comparison of the sizes of the hyperechoes in US images and the protein denaturing area on optical images. Bovine liver specimens were segmented to reveal the lesion's terminal sizes. Differences between actual lesion volume and hyperechoes in US images were demonstrated to be dependent on acoustic frequency and intensity. At a low frequency (1?MHz), the hyperechoes appeared to be larger than the actual volume, but the difference decreased with the duration of ablation. In contrast, at a high frequency (3.5?MHz), the hyperechoes were smaller for ablations lasting longer than 10?s. Moreover, given certain low-intensity conditions, lesions were formed without detectable hyperechoes (3.5?MHz), or hyperechoes appeared before a visible lesion was formed (1?MHz). Dual frequency sonications (low frequency followed by high frequency) produce more stable and larger lesions, and with less position shift, which might be useful for designing future ablation strategies.     

Optical coherence tomography: an emerging technology for biomedical imaging and optical biopsy

Optical coherence tomography (OCT) is an emerging technology for performing high-resolution cross-sectional imaging. OCT is analogous to ultrasound imaging, except that it uses light instead of sound. OCT can provide cross-sectional images of tissue structure on the micron scale in situ and in real time. Using OCT in combination with catheters and endoscopes enables high-resolution intraluminal imaging of organ systems. OCT can function as a type of optical biopsy and is a powerful imaging technology for medical diagnostics because unlike conventional histopathology which requires removal of a tissue specimen and processing for microscopic examination, OCT can provide images of tissue in situ and in real time. OCT can be used where standard excisional biopsy is hazardous or impossible, to reduce sampling errors associated with excisional biopsy, and to guide interventional procedures. In this paper, we review OCT technology and describe its potential biomedical and clinical applications.     

Advanced ultrasonography technologies to assess the effects of radiofrequency ablation on hepatocellular carcinoma

Background

Radiofrequency ablation (RFA) is a curative therapy for hepatocellular carcinoma (HCC). In RFA, ultrasonography (US) is most commonly used to guide tumor puncture, while its effects are assessed using dynamic computed tomography or magnetic resonance. The differences in modalities used for RFA and assessment of its effects complicate RFA. We developed a method for assessing the effects of RFA on HCC by combining contrast-enhanced (CE) US and real-time virtual sonography with three-dimensional US data.

Patients and methods

Before RFA, we performed a sweep scan of the target HCC nodule and the surrounding hepatic parenchyma to generate three-dimensional US data. After RFA, we synchronized multi-planar reconstruction images derived from stored three-dimensional US data with real-time US images on the same US monitor and performed CEUS and real-time virtual sonography. Using a marking function, we drew a sphere marker along the target HCC nodule contour on pre-treatment US- multi-planar reconstruction images so that the automatically synchronized sphere marker represented the original HCC nodule contour on post-treatment real-time CEUS images. Ablation was considered sufficient when an avascular area with a margin of several millimeters in all directions surrounded the sphere marker on CEUS.

Results

This method was feasible and useful for assessing therapeutic effects in 13 consecutive patients with HCC who underwent RFA. In 2 patients who underwent multiple sessions of RFA, HCC-nodule portions requiring additional RFA were easily identified on US images.

Conclusions

This method using advanced US technologies will facilitate assessment of the effects of RFA on HCC.     

甲状腺癌的B超与CT检查表现及意义

目的:探讨B超及CT检查对甲状腺癌的诊断价值。方法:回顾性分析189例甲状腺癌患者的B超及CT检查,了解甲状腺癌在B超及CT检查中的表现,并比较两者的优缺点。结果:B超及CT检查对甲状腺肿快的检出率为100%,B超诊断TC的符合率为50.7%,CT为81.6%,CT诊断颈部淋巴结转移的符合率为51.4%,B超为74.0%。结论:CT对甲状腺癌定性诊断正确率高于B超检查,B超发现颈部淋巴结转移要优于CT,B超应作为检查颈部肿块的首选办法。     

Optical Coherence Tomography: Feasibility for Basic Research and Image-guided Surgery of Breast Cancer

Diagnostic trends in medicine are being directed toward cellular and molecular processes, where treatment regimens are more amenable for cure. Optical imaging is capable of performing cellular and molecular imaging using the short wavelengths and spectroscopic properties of light. Diffuse optical tomography is an optical imaging technique that has been pursued as an alternative to X-ray mammography. While this technique permits non-invasive optical imaging of the whole breast, to date it is incapable of resolving features at the cellular level. Optical coherence tomography (OCT) is an emerging high-resolution biomedical imaging technology that for larger and undifferentiated cells can perform cellular-level imaging at the expense of imaging depth. OCT performs optical ranging in tissue and is analogous to ultrasound except reflections of near-infrared light are detected rather than sound. In this paper, an overview of the OCT technology is provided, followed by images demonstrating the feasibility of using OCT to image cellular features indicative of breast cancer. OCT images of a well-established carcinogen-induced rat mammary tumor model were acquired. Images from this common experimental model show strong correlation with corresponding histopathology. These results illustrate the potential of OCT for a wide range of basic research studies and for intra-operative image-guidance to identify foci of tumor cells within surgical margins during the surgical treatment of breast cancer.     

超声成像联合光散射成像系统对乳腺肿瘤良恶性鉴别的应用价值

目的：探讨超声成像联合光散射成像系统（简称“超声光子”）对鉴别乳腺良、恶性肿瘤的临床应用价值。方法：随机选取74例乳腺肿物患者行超声光子检查，通过高频超声引导对肿物定位，以多波段的光子对肿物内血氧代谢、新生血管密度等生理参数进行功能成像，将结果量化规入北美放射协会制定的BI—RADS分级，（1～3级）为良性可能性大，（4～5级）为恶性可能性大，与术后病理对照分析，评价其诊断符合率。结果：超声光子诊断结果良性（1—3级）30例，恶性（4～5级）44例。术后病理诊断良性病变34例，恶性病变40例。敏感性95％（38／40），特异性82．4％（28／34），准确度89．2％（66／74）。结论：超声光散射成像系统能够有效区分乳腺良、恶性肿瘤。其不仅能够从超声二维的结构成像对肿瘤获取信息进行评价；又可以通过光学系统，从肿瘤的功能成像上获取更为深入的诊断。超声光散射成像系统开辟了早期乳腺癌检测的新领域，对提高乳腺癌的早期诊断，减少漏诊、误诊率具有重要价值。     

浅表组织及乳腺侵袭性纤维瘤病的超声表现及价值

目的 探讨浅表组织及乳腺侵袭性纤维瘤病(AF)的超声图像表现及弹性图像特征,提高对这类病变的超声认识和诊断.方法 针对5例AF的超声彩色多普勒图像及超声弹性成像结果 进行分析.结果 本组共5例,其中发生在乳腺3 例、右髂部腹壁下肌层1例,左侧腹股沟肌层1例,其二维图像结果 均提示倾向恶性.3例乳腺病灶并采用实时弹性成像技术(UE)进行评分,评分结果 均为4～5分,提示病灶组织较硬.2例位于右髂部腹壁下及左侧腹股沟区的病灶,由于包块较大,未采用弹性成像技术.结论 侵袭性纤维瘤病是一种少见的中间型肿瘤,超声图像有一定特征,但鉴别诊断仍有一定难度.超声能为临床提供病灶位置、毗邻关系及浸润范围等信息,有一定的价值.     

超声光散射乳腺成像诊断乳腺癌的临床价值

目的 探讨运用超声光散射乳腺成像（OPTIMUS）系统对乳腺肿块的诊断价值。方法回顾经病理检查证实的136例乳腺肿瘤的OPTIMUS系统表现,与病理检查结果对比分析,同时用一致性检验评价其与病理、超声、钼靶X线检查的一致性,并绘制受试者工作特征（receiver operating characteristic,ROC）曲线,计算曲线下面积（area under the curve,Auc）,判断三种检查手段的准确性,评价OPTIMUS系统的临床应用价值。结果136例患者术后病理诊断良性病变50例,恶性病变86例。OPTIMUS系统诊断良性病变34例,恶性病变102例,其中16例被过度诊断为恶性。其与超声及钼靶X线检查的一致性检验Kappa值分别为0．536、0．386。0PTIMUS系统、超声、钼靶X线与病理检查的一致性检验Kappa值分别为0．729、0．616、0．649。OPTIMUS系统、超声及钼靶X线检查的AUC分别为0．840（95％C10．764～0．916）、0．817（95％CI0．742～0．893）及0．837（95％CI0．771～0．902）。结论OPTIMUS系统对诊断乳腺恶性肿瘤的准确性及敏感性较高,可以提高乳腺癌患者的检出率,减低漏诊率。     

Optical biopsy of lymph node morphology using optical coherence tomography

Optical diagnostic imaging techniques are increasingly being used in the clinical environment, allowing for improved screening and diagnosis while minimizing the number of invasive procedures. Diffuse optical tomography, for example, is capable of whole-breast imaging and is being developed as an alternative to traditional X-ray mammography. While this may eventually be a very effective screening method, other optical techniques are better suited for imaging on the cellular and molecular scale. Optical Coherence Tomography (OCT), for instance, is capable of high-resolution cross-sectional imaging of tissue morphology. In a manner analogous to ultrasound imaging except using optics, pulses of near-infrared light are sent into the tissue while coherence-gated reflections are measured interferometrically to form a cross-sectional image of tissue. In this paper we apply OCT techniques for the high-resolution three-dimensional visualization of lymph node morphology. We present the first reported OCT images showing detailed morphological structure and corresponding histological features of lymph nodes from a carcinogen-induced rat mammary tumor model, as well as from a human lymph node containing late stage metastatic disease. The results illustrate the potential for OCT to visualize detailed lymph node structures on the scale of micrometastases and the potential for the detection of metastatic nodal disease intraoperatively.     

Corona enhancement in ultrasonographical post-vascular phase images with microbubble contrast agent: a novel specific sign for hepatocellular carcinomas

In 1.5 Harmonic Imaging ultrasonography (1.5 HI US), images are obtained in a band intermediate between the fundamental and 2nd harmonic components, resulting in stronger contrast enhancement than in conventional harmonic imaging. We attempted to assess the hemodynamics of hepatocellular carcinomas (HCC) with special attention to blood drainage using 1.5 HI US. Forty-two HCC nodules, metastatic liver tumors and hepatic hemangiomas were studied. In contrast studies, intermittent ultrasound transmission was performed for a period of up to 45 sec after the injection of contrast agent, which was regarded as the vascular phase. The time point of 5 min later was specified as the post-vascular phase, and images were obtained by single manual transmission for comparison of contrast enhancement with surrounding hepatic parenchyma. In addition, histological examination was performed. 1.5 HI US clearly demonstrated the strong tumor vessels in most HCCs. Corona enhancement, in which the areas surrounding the tumor are enhanced, was observed in 71.4% (30/42) of HCC nodules during the post-vascular phase. This sign was not observed in any other tumors. Histological findings revealed that CD34-positive-endothelial cells were prominent in the surrounding area of HCC. In conclusion, 1.5 HI US is an effective tool for evaluating hemodynamics in both early- and post-vascular phase. Corona enhancement may be due to the trapping of contrast agent in the endothelial cells in the surround of HCC nodules and be a novel specific sign for HCC.     

Real-time optical imaging of primary tumor growth and multiple metastatic events in a pancreatic cancer orthotopic model

We report here whole-body optical imaging, in real time, of genetically fluorescent pancreatic tumors growing and metastasizing to multiple sites in live mice. The whole-body optical imaging system is external and noninvasive. Human pancreatic tumor cell lines, BxPC-3 and MiaPaCa-2, were engineered to stably express high-levels of the Aequorea victoria green fluorescent protein (GFP). The GFP-expressing pancreatic tumor cell lines were surgically orthotopically implanted as tissue fragments in the body of the pancreas of nude mice. Whole-body optical images visualized real-time primary tumor growth and formation of metastatic lesions that developed in the spleen, bowel, portal lymph nodes, omentum, and liver. Intravital images in the opened animal confirmed the identity of whole-body images. The whole-body images were used for real-time, quantitative measurement of tumor growth in each of these organs. Intravital imaging was used for quantification of growth of micrometastasis on the liver and stomach. Whole-body imaging was carried out with either a trans-illuminated epi-fluorescence microscope or a fluorescence light box, both with a thermoelectrically cooled color CCD camera. The simple, noninvasive, and highly selective imaging made possible by the strong GFP fluorescence allowed detailed simultaneous quantitative imaging of tumor growth and multiple metastasis formation of pancreatic cancer. The GFP imaging affords unprecedented continuous visual monitoring of malignant growth and spread within intact animals without the need for anesthesia, substrate injection, contrast agents, or restraint of animals required by other imaging methods. The GFP imaging technology presented in this report will facilitate studies of modulators of pancreatic cancer growth, including inhibition by potential chemotherapeutic agents.     

Transrectal ultrasound-integrated spectral optical tomography of hypoxic progression of a regressing tumor in a canine prostate

The objective of this study was to evaluate if transrectal optical tomography implemented at three wavelength bands for spectral detection could monitor changes of the hemoglobin oxygen saturation (StO2) in addition to those of the total hemoglobin concentration ([HbT]) in lesions of a canine prostate, including an induced tumor modeling canine prostate cancer. Near-infrared (NIR) optical tomography was integrated with ultrasound (US) for transrectal imaging. Multi-spectral detection at 705_nm, 785_nm and 808_nm rendered measurements of [HbT] and StO2. Canine transmissible venereal tumor (TVT) cells were injected into the right lobe of a dog's prostate gland, which had a pre-existing cyst in the left lobe. Longitudinal assessments of the prostate were performed weekly over a 63-day duration by NIR imaging concurrent with grey-scale and Doppler US. Ultrasonography revealed a bi-lobular tumor-mass regressing from day-49 to day-63. At day-49 this tumor-mass developed a hypoxic core that became larger and more intense by day-56 and expanded further by day-63. The tumor-mass presented a strong hyper-[HbT] feature on day-56 that was inconsistent with US-visualized blood flow. Histology confirmed two necrotic TVT foci within this tumor-mass. The cyst appeared to have a large anoxic-like interior that was greater in size than its ultrasonographically delineated lesion, and a weak lesional elevation of [HbT]. On day-56, the cyst presented a strong hyper-[HbT] feature consistent with US-resolved blood flow. Histology revealed acute and chronic hemorrhage in the periphery of the cyst. The NIR imaging features of two other TVT nodules and a metastatic lymph node were evaluated retrospectively. Transrectal US-integrated spectral optical tomography seems to enable longitudinal monitoring of intra-lesional oxygenation dynamics in addition to the hemoglobin content of lesions in the canine prostate.     

Combination of digital mammography with semi-automated 3D breast ultrasound

This paper describes work aimed at combining 3D ultrasound with full-field digital mammography via a semi-automatic prototype ultrasound scanning mechanism attached to the digital mammography system gantry. Initial efforts to obtain high x-ray and ultrasound image quality through a compression paddle are proving successful. Registration between the x-ray mammogram and ultrasound image volumes is quite promising when the breast is stably compressed. This prototype system takes advantage of many synergies between the co-registered digital mammography and pulse-echo ultrasound image data used for breast cancer detection and diagnosis. In addition, innovative combinations of advanced US and X-ray applications are being implemented and tested along with the basic modes. The basic and advanced applications are those that should provide relatively independent information about the breast tissues. Advanced applications include x-ray tomosynthesis, for 3D delineation of mammographic structures, and non-linear elasticity and 3D color flow imaging by ultrasound, for mechanical and physiological information unavailable from conventional, non-contrast x-ray and ultrasound imaging.     

Diagnostic imaging approaches and relationship to hepatobiliary cancer staging and therapy

Diagnostic imaging plays an essential role in management of hepatobiliary tumors. High resolution images provided by computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US) allow detection of tumor within the liver. CT arterial portography remains the standard for detection of small lesions in the range of 1.5 cm, but noninvasive techniques such as contrast-enhanced helical CT and MR hold promise for comparable lesion detection. MRI provides lesion characterization for differentiation of benign and malignant tumors. Lesion characterization has been further improved by faster CT and MR techniques that allow imaging in both arterial and portal venous phases for characterization of lesions based on the rate and pattern of enhancement. Functional imaging such as 2-fluoro-2-deoxy-D-glucose-positron-emission tomography (FDG-PET) is increasingly utilized for detection of intrahepatic tumor and extrahepatic disease. Accuracy of FDG-PET for extrahepatic disease is better than conventional imaging and has been shown to change management in a significant number of patients. Imaging is also invaluable for surgical planning. Segmental anatomy is well shown by CT, MRI, and US. CT or MR angiography with newer 3D techniques delineate vascular variants and areas of encasement or occlusion by tumor. Biliary involvement at the hilus may be shown by US and MR cholangiography. Imaging detection of vascular involvement, bile duct extension, and lobar atrophy may alter the surgical approach.     

E5. Breast ultrasound – update

The advances made in recent years in high frequency ultrasound (US) transducer technology using broad bandwidth and high-dynamic range technology have led to considerable improvements in two-dimensional (2D) and three-dimensional (3D) greyscale diagnostic imaging of the breast. The role of elastography, focusing on the differentiation between benign and malignant lesions, continues to be evaluated. US is the method of choice to assess and sample, with core biopsy, most breast abnormalities, while stereotactical guided vacuum assisted biopsy (VAB) is the method of choice to sample screen-detected microcalcifications and architectural distortions not seen on US. In the dense breast, the addition of US to screening mammography improves the sensitivity for cancer considerably. The mean supplemental diagnostic yield of US after negative mammography is 3.2 per 1000 women with dense breasts. US is the first line imaging technique for symptomatic breast patients and women under the age of 40. The International Breast Ultrasound School (IBUS) and Breast Imaging-Reporting and Data System (BI-RADS) breast US guidelines have introduced some consistency to examination technique and reporting. Intraoperative surgeon-performed ultrasound focuses on the accurate definition of the resection segment or sector and the margin analysis of the resection specimen. US-guided VAB is being used increasingly for diagnosis of borderline lesions, to complete preoperative staging in patients with extensive ductal component and for therapeutic excision. Magnetic resonance imaging (MRI) is useful preoperatively to assess the extent of ipsilateral disease and to exclude the contralateral breast cancer, particularly for women at increased risk of mammographically occult disease.     

Comparative Efficacy of Four Imaging Instruments for Breast Cancer Screening

Sensitivity and specificity are the two most important indicators in selection of medical imaging devices forcancer screening. Breast images taken by conventional or digital mammography, ultrasound, MRI and opticalmammography were collected from 2,143,852 patients. They were then studied and compared for sensitivityand specificity results. Optical mammography had the highest sensitivity (p<0.001 and p<0.006) except withMRI. Digital mammography had the highest specificity for breast cancer imaging. A comparison of specificitybetween digital mammography and optical mammography was significant (p<0.021). If two or more breastdiagnostic imaging tests are requested the overall sensitivity and specificity will increase. In this literature reviewstudy patients at high-risk of breast cancer were studied beside normal or sensitive women. The image modalityperformance of each breast test was compared for each.     

Role of mammogram and ultrasound imaging in predicting breast cancer subtypes in screening and symptomatic patients

BACKGROUNDBreast cancer (BC) radiogenomics, or correlation analysis of imaging features and BC molecular subtypes, can complement genetic analysis with less resource-intensive diagnostic methods to provide an early and accurate triage of BC. This is pertinent because BC is the most prevalent cancer amongst adult women, resulting in rising demands on public health resources. AIMTo find combinations of mammogram and ultrasound imaging features that predict BC molecular subtypes in a sample of screening and symptomatic patients. METHODSThis retrospective study evaluated 328 consecutive patients in 2017-2018 with histologically confirmed BC, of which 237 (72%) presented with symptoms and 91 (28%) were detected via a screening program. All the patients underwent mammography and ultrasound imaging prior to biopsy. The images were retrospectively read by two breast-imaging radiologists with 5-10 years of experience with no knowledge of the histology results to ensure statistical independence. To test the hypothesis that imaging features are correlated with tumor subtypes, univariate binomial and multinomial logistic regression models were performed. Our study also used the multivariate logistic regression (with and without interaction terms) to identify combinations of mammogram and ultrasound (US) imaging characteristics predictive of molecular subtypes.RESULTSThe presence of circumscribed margins, posterior enhancement, and large size is correlated with triple-negative BC (TNBC), while high-risk microcalcifications and microlobulated margins is predictive of HER2-enriched cancers. Ductal carcinoma in situ is characterized by small size on ultrasound, absence of posterior acoustic features, and architectural distortion on mammogram, while luminal subtypes tend to be small, with spiculated margins and posterior acoustic shadowing (Luminal A type). These results are broadly consistent with findings from prior studies. In addition, we also find that US size signals a higher odds ratio for TNBC if presented during screening. As TNBC tends to display sonographic features such as circumscribed margins and posterior enhancement, resulting in visual similarity with benign common lesions, at the screening stage, size may be a useful factor in deciding whether to recommend a biopsy.CONCLUSIONSeveral imaging features were shown to be independent variables predicting molecular subtypes of BC. Knowledge of such correlations could help clinicians stratify BC patients, possibly enabling earlier treatment or aiding in therapeutic decisions in countries where receptor testing is not readily available.