Multimodality Imaging of Benign and Malignant Diseases of the Nipple-Areolar Complex.

The nipple-areolar complex (NAC), a unique anatomic structure of the breast, encompasses the terminal intramammary ducts and skin appendages. Several benign and malignant diseases can arise within the NAC. As several conditions have overlapping symptoms and imaging findings, understanding the distinctive nipple anatomy, as well as the clinical and imaging features of each NAC disease process, is essential. A multimodality imaging approach is optimal in the presence or absence of clinical symptoms. The authors review the ductal anatomy and anomalies, including congenital abnormalities and nipple retraction. They then discuss the causes of nipple discharge and highlight best practices for the imaging workup of pathologic nipple discharge, a common condition that can pose a diagnostic challenge and may be the presenting symptom of breast cancer. The imaging modalities used to evaluate and differentiate benign conditions (eg, dermatologic conditions, epidermal inclusion cyst, mammary ductal ectasia, periductal mastitis, and nonpuerperal abscess), benign tumors (eg, papilloma, nipple adenoma, and syringomatous tumor of the nipple), and malignant conditions (eg, breast cancer and Paget disease of the breast) are reviewed. Breast MRI is the current preferred imaging modality used to evaluate for NAC involvement by breast cancer and select suitable candidates for nipple-sparing mastectomy. Different biopsy techniques (US -guided biopsy and stereotactic biopsy) for sampling NAC masses and calcifications are described. This multimodality imaging approach ensures an accurate diagnosis, enabling optimal clinical management and patient outcomes. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Multimodality Imaging for 3D Printing and Surgical Rehearsal in Complex Spine Surgery.

Surgery is the mainstay treatment of symptomatic spinal tumors. It aids in restoring functionality, managing pain and tumor growth, and improving overall quality of life. Over the past decade, advancements in medical imaging techniques combined with the use of three-dimensional (3D) printing technology have enabled improvements in the surgical management of spine tumors by significantly increasing the precision, accuracy, and safety of the surgical procedures. For complex spine surgical cases, the use of multimodality imaging is necessary to fully visualize the extent of disease, including both soft-tissue and bone involvement. Integrating the information provided by these examinations in a cohesive manner to facilitate surgical planning can be challenging, particularly when multiple surgical specialties work in concert. The digital 3-dimensional (3D) model or 3D rendering and the 3D printed model created from imaging examinations such as CT and MRI not only facilitate surgical planning but also allow the placement of virtual and physical surgical or osteotomy planes, further enhancing surgical planning and rehearsal. The authors provide practical information about the 3D printing workflow, from image acquisition to postprocessing of a 3D printed model, as well as optimal material selection and incorporation of quality management systems, to help surgeons utilize 3D printing for surgical planning. The authors also highlight the process of surgical rehearsal, how to prescribe digital osteotomy planes, and integration with intraoperative surgical navigation systems through a case-based discussion. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Clinical situations for which 3D Printing is considered an appropriate representation or extension of data contained in a medical imaging examination: vascular conditions.

BACKGROUND: Medical three-dimensional (3D) printing has demonstrated utility and value in anatomic models for vascular conditions. A writing group composed of the Radiological Society of North America (RSNA) Special Interest Group on 3D Printing (3DPSIG) provides appropriateness recommendations for vascular 3D printing indications. METHODS: A structured literature search was conducted to identify all relevant articles using 3D printing technology associated with vascular indications. Each study was vetted by the authors and strength of evidence was assessed according to published appropriateness ratings. RESULTS: Evidence-based recommendations for when 3D printing is appropriate are provided for the following areas: aneurysm, dissection, extremity vascular disease, other arterial diseases, acute venous thromboembolic disease, venous disorders, lymphedema, congenital vascular malformations, vascular trauma, vascular tumors, visceral vasculature for surgical planning, dialysis access, vascular research/development and modeling, and other vasculopathy. Recommendations are provided in accordance with strength of evidence of publications corresponding to each vascular condition combined with expert opinion from members of the 3DPSIG. CONCLUSION: This consensus appropriateness ratings document, created by the members of the 3DPSIG, provides an updated reference for clinical standards of 3D printing for the care of patients with vascular conditions.

Radiological Society of North America (RSNA) 3D Printing Special Interest Group (SIG) clinical situations for which 3D printing is considered an appropriate representation or extension of data contained in a medical imaging examination: breast conditions.

The use of medical 3D printing has expanded dramatically for breast diseases. A writing group composed of the Radiological Society of North America (RSNA) Special Interest Group on 3D Printing (SIG) provides updated appropriateness criteria for breast 3D printing in various clinical scenarios. Evidence-based appropriateness criteria are provided for the following clinical scenarios: benign breast lesions and high-risk breast lesions, breast cancer, breast reconstruction, and breast radiation (treatment planning and radiation delivery).

Mid-treatment Ultrasound Descriptors as Qualitative Imaging Biomarkers of Pathologic Complete Response in Patients with Triple-Negative Breast Cancer.

This study aimed to investigate mid-treatment breast tumor ultrasound characteristics that may predict eventual pathologic complete response (pCR) in triple-negative breast cancer; specifically, we examined associations between pCR and two parameters: tumor response pattern and tumor appearance. Ultrasound was performed at mid-treatment, defined as the completion of four cycles of anthracycline-based chemotherapy and before receiving taxane-based chemotherapy. Consensus imaging review was performed while blinded to pathology results (i.e., pCR/non-pCR) from surgery. Tumor response pattern was described as "complete," "concentric," "fragmented," "stable" or "progression." Tumor appearance was designated as "mass," "architectural distortion," "flat tumor bed" or "clip only." Univariate and multivariate regression analyses of 144 participants showed significant associations between mid-treatment response pattern and pCR (p = 0.0348 and p = 0.0173, respectively), with complete and concentric response patterns more likely to achieve pCR than other patterns. Univariate and multivariate regression analyses further showed significant associations between mid-treatment tumor appearance and pCR (p < 0.0001 for both), with persistent appearance of mass less likely than other appearances to achieve pCR. To conclude, our study demonstrated strong associations between pCR and both tumor response pattern and tumor appearance, thereby suggesting that these parameters have potential as qualitative imaging biomarkers of pCR in triple-negative breast cancer.

Acceptability of 3D-printed breast models and their impact on the decisional conflict of breast cancer patients: A feasibility study.

PURPOSE: To evaluate the acceptability and impact of 3D-printed breast models (3D-BMs) on treatment-related decisional conflict (DC) of breast cancer patients. METHODS: Patients with breast cancer were accrued in a prospective institutional review board-approved trial. All patients underwent contrast-enhanced breast magnetic resonance imaging (MRI). A personalized 3D-BM was derived from MRI. DC was evaluated pre- and post-3D-BM review. 3D-BM acceptability was assessed post-3D-BM review. RESULTS: DC surveys before and after 3D-BM review and 3D-BM acceptability surveys were completed by 25 patients. 3D-BM were generated in two patients with bilateral breast cancer. The mean patient age was 48.8 years (28-72). The tumor stage was Tis (7), 1 (8), 2 (8), and 3 (4). The nodal staging was 0 (19), 1 (7), and 3 (1). Tumors were unifocal (15), multifocal (8), or multicentric (4). Patients underwent mastectomy (13) and segmental mastectomy (14) with (20) or without (7) oncoplastic intervention. Neoadjuvant therapy was given to seven patients. Patients rated the acceptability of the 3D-BM as good/excellent in understanding their condition (24/24), understanding disease size (25/25), 3D-BM detail (22/25), understanding their surgical options (24/25), encouraging to ask questions (23/25), 3D-BM size (24/25), and impartial to surgical options (17/24). There was a significant reduction in the overall DC post-3D-BM review, indicating patients became more assured of their treatment choice (p = 0.002). Reduction post-3D-BM review was also observed in the uncertainty (p = 0.012), feeling informed about options (p = 0.005), clarity about values (p = 0.032), and effective (p = 0.002) Decisional Conflict Scale subscales. CONCLUSIONS: 3D-BMs are an acceptable tool to decrease DC in breast cancer patients.

Axillary ultrasound during neoadjuvant systemic therapy in triple-negative breast cancer patients.

PURPOSE: To investigate the value of performing mid-treatment axillary ultrasound (AUS) in triple-negative breast cancer (TNBC) patients who are undergoing neoadjuvant systemic therapy (NAST) by determining the optimal cutoff number of abnormal nodes associated with residual nodal disease on surgical pathology. MATERIALS AND METHODS: This sub-study, an interim analysis of an ongoing single-institution clinical trial enrolling patients with stage I-III TNBC, included 106 patients. Number of abnormal nodes at mid-treatment was assessed and recorded by experienced breast radiologists, who empirically categorized lymph nodes using a binary approach of sonographically-normal versus abnormal. Pathologic lymph node positivity was defined as presence of macrometastasis or micrometastasis in ≥1 axillary node from sentinel lymph node biopsy and/or axillary lymph node dissection. RESULTS: Of 106 patients, 26 (25 %) had residual nodal disease and 80 (75 %) had no nodal disease at surgery. Median number of abnormal nodes at mid-treatment was 5 (standard deviation [SD], 5) for patients with residual nodal disease and 0 (SD, 2) for patients with no nodal disease at surgery (p < 0.0001). TNBC patients with >4 abnormal nodes at mid-treatment had a significantly higher chance of being node-positive at surgery (AUC = 0.908, p < 0.0001; PPV = 90 %). CONCLUSION: Our data suggest that a cutoff of >4 abnormal nodes on mid-treatment AUS is associated with residual disease post-NAST. If our findings are substantiated by subsequent analyses, then mid-treatment AUS could be used to identify patients unlikely to achieve nodal pathologic complete response and who should be offered alternative therapy.

Breast Implant Imaging Surveillance among U.S. Plastic Surgeons: U.S. Food and Drug Administration Recommendations versus Clinical Reality.

BACKGROUND: Device rupture is considered a major complication associated with breast implants. The U.S. Food and Drug Administration recommends magnetic resonance imaging (MRI) surveillance 3 years after implantation and then every 2 years, but adherence to these recommendations is poor. The authors identified current practice management for breast implant rupture surveillance by surveying practicing U.S. plastic surgeons. METHODS: An online survey of all active members of the American Society of Plastic Surgeons was performed. Questions analyzed imaging practice patterns related to breast implants. Logistic regression models were used to analyze determinants for radiographic imaging in breast implant patients. RESULTS: The survey had a response rate of 16.5 percent. For patients with breast implants, 37.7 percent of respondents recommended MRI at the recommended intervals. Fifty-five percent perform imaging only if there is a problem with the implant. Academic surgeons more frequently recommended MRI (56.3 percent and 39.3 percent; p = 0.0002). Surgeons with less than 5 years of experience are four times more likely to order MRI than surgeons with over 25 years' experience (60.8 percent and 28.1 percent; p < 0.0001). Furthermore, lower volume surgeons recommend significantly more MRI (45.2 percent and 27.3 percent; p = 0.001). Respondents are almost two times more likely to recommend MRI in reconstructive versus cosmetic patients (51.2 percent and 35.6 percent; p = 0.0004). CONCLUSIONS: MRI limitations include high costs, time commitments, and equipment constraints. Fewer than 40 percent of survey respondents suggest the recommended screening frequency to their patients; however, academic, low-volume, early-career surgeons are more likely to recommend MRI implant monitoring. Screening recommendations need to be evidence based and align with common practices to prevent undue system, provider, and patient burden.

Application of Three-Dimensional Printed Vascular Modeling as a Perioperative Guide to Perforator Mapping and Pedicle Dissection during Abdominal Flap Harvest for Breast Reconstruction.

BACKGROUND: Advancements in three-dimensional (3D) printing have enabled production of patient-specific guides to aid perforator mapping and pedicle dissection during abdominal flap harvest. We present our early experience using this tool to navigate deep inferior epigastric artery (DIEA) topography and evaluate its impact on operative efficiency and clinical outcomes. PATIENTS AND METHODS: Between January 2013 and December 2018, a total of 50 women underwent computed tomographic angiography (CTA)-guided perforator mapping prior to abdominal flap breast reconstruction, with (n = 9) and without (n = 41) 3D-printed vascular modeling (3DVM). Models were assessed for their accuracy in identifying perforator location and source-vessel anatomy, as determined by operative findings from 18 hemi-abdomens. The margin of error (MOE) for perforator localization using 3DVM was calculated and compared with CTA-derived measurements for the same patients. Flap harvest times, outcomes, and complications for patients who were preoperatively mapped using 3DVM versus CTA alone were analyzed. RESULTS: Overall, complete concordance was observed between 3DVM and operative findings with regards to perforator number, source-vessel origin, and DIEA branching pattern. By comparison, CTA interpretation of these parameters inaccurately identified branching pattern and perforator source-vessel origin in 28 and 33% of hemi-abdomens, respectively (p = 0.045 and p = 0.02). Compared with operative measurements, the average MOE for perforator localization using 3DVM was significantly lower than that obtained from CTA alone (0.81 vs. 8.71 mm, p < 0.0001). Reference of 3D-printed models, intraoperatively, was associated with a mean reduction in flap harvest time by 21 minutes (60.7 vs. 81.7 minutes, p < 0.001). Although not statistically significant, rates of perforator-level injury, microvascular insufficiency, and fat necrosis were lower among patients mapped using 3DVM. CONCLUSION: The results of this study support the accuracy of 3DVM for identifying DIEA topography and perforator location. Application of this technology may translate to enhanced operative efficiency and fewer perfusion-related complications for patients undergoing abdominal free flap breast reconstruction.

The role of three-dimensional printing in the surgical management of breast cancer.

A patient-specific 3-dimensional printed model (3DPM) of a woman with breast cancer was created. Mastectomy was favored as BCS would necessitate significant breast size alteration due to the extent of disease. After review of the 3D printed model, the patient and surgeon agreed on breast-conserving surgery. Use of patient-specific 3DPM in the setting of breast cancer may aid patient decision making and surgical planning, leading to enhanced surgical and oncological outcomes.

Imaging features of triple-negative breast cancers according to androgen receptor status.

OBJECTIVE: Different molecular subtypes of triple-negative breast cancer (TNBC) have previously been identified through analysis of gene expression profiles. The luminal androgen receptor (LAR) subtype has been shown to have a lower rate of pathologic complete response to neoadjuvant chemotherapy than other TNBC subtypes. The purpose of this study was to determine if the imaging features of TNBCs differ by AR (androgen receptor) status, which is a surrogate immunohistochemical (IHC) marker for the chemoresistant LAR subtype of TNBC. MATERIALS AND METHODS: This sub-study was part of a clinical trial in patients with stage I-III TNBC who were prospectively monitored for response while receiving neoadjuvant systemic therapy (NAST) at a single comprehensive cancer center. This interim imaging analysis included 144 patients with known AR status measured by IHC. AR-positive (AR+) tumors were defined as those in which at least 10% of tumor cells had positive nuclear AR staining. Two experienced, fellowship-trained breast radiologists who were blinded to the IHC results retrospectively reviewed and reached consensus on all imaging studies for the index lesion (i.e., mammogram, ultrasound, and breast magnetic resonance imaging). The index lesion for each patient was reviewed and described according to the fifth edition of the Breast Imaging Reporting and Data System lexicon. Logistic regression modeling was used to identify imaging features predictive of AR status. p ≤ 0.05 was considered statistically significant. RESULTS: Univariate logistic regression models for AR status showed that AR+ TNBC was significantly associated with heterogeneously dense breast composition on mammography (p = 0.02), mass with calcifications (p = 0.05), irregular mass shape on mammography (p = 0.03), and irregular mass shape on sonography (p = 0.003). Multivariate logistic regression models for AR status showed that AR+ TNBC was significantly associated with heterogeneously dense breast composition on mammography (p = 0.01), high mass density on mammography (p = 0.003), and irregular mass shape on sonography (p = 0.0004). CONCLUSION: The imaging features of TNBCs differ by AR status. Multimodality breast imaging may help identify the LAR subtype of TNBC, which has been shown to be a subtype that is relatively resistant to neoadjuvant chemotherapy.

Imaging of Intracystic Papillary Carcinoma.

OBJECTIVE: To describe the clinical, imaging, and histopathologic findings of intracystic papillary carcinoma (IPC) of the breast. MATERIALS AND METHODS: Following institutional review board approval, a database at a single institution was searched to identify cases of patients who received a diagnosis of IPC from 1999-2013 and who had undergone preoperative imaging with mammography, sonography, or MRI. The clinical, mammographic, sonographic, and MRI features of IPC were compared and analyzed using the BI-RADS mammography, ultrasound, and MRI lexicons. RESULTS: The study sample included 40 patients, 36 females and 4 males. The most common clinical presentation was a palpable mass. Mammographic data was assessed in 31 patients. A tumor was mammographically occult in one patient. The predominant features were oval shape of 17 tumors (57%), obscured margins of 12 (40%), and high density of 20 (67%). Ultrasound data of 37 patients revealed 20 oval masses, 13 irregular masses, and 4 round masses. Fourteen complex solid and cystic masses were identified. One patient underwent MRI that showed a complex, enhancing mass with washout kinetics. Ultrasound guided biopsy was performed on 33 of the 37 masses. Core needle biopsy and fine needle aspiration (FNA) biopsy were most commonly performed on the solid components of the complex solid and cystic masses. IPC was diagnosed by stereotactic biopsy in 1 patient with a suspicious mass on mammography with no correlate on sonography and 6 patients had surgical excision without imaging-guided biopsy. Pathology showed in situ IPC in 31/40 tumors and 11 were solid and cystic complex masses on ultrasound. Pathology revealed invasive IPC in 9 tumors and five had an irregular mass on ultrasound. CONCLUSION: Our study reveals no specific imaging features to differentiate in situ vs invasive IPC. The most common ultrasound feature in biopsy proven IPC was an oval mass, however, we identified that a complex solid and cystic mass is more often associated with the diagnosis of in situ IPC and an irregular mass is more often associated with the diagnosis of invasive IPC. Future studies with larger cohorts are needed to further define the clinical and imaging features of this rare malignancy.

Histopathologic correlation of residual mammographic microcalcifications after neoadjuvant chemotherapy for locally advanced breast cancer.

OBJECTIVE: This study was designed to determine the histopathologic correlation at surgery of residual mammographic calcifications in patients after neoadjuvant chemotherapy (NAC) for locally advanced breast cancer (LABC). METHODS: This single-institution, retrospective study was approved by the Institutional Review Board and was Health Insurance Portability and Accountability act compliant. Women with LABC who underwent NAC between January 1, 2004 and December 31, 2008 and had mammography performed before and after NAC available for review were included in this study. The extent of microcalcifications associated with cancer before and after the completion of NAC was correlated with histopathology and biomarker status. RESULTS: Of 494 patients who met the inclusion criteria, 106 demonstrated microcalcifications on pre-, post-chemotherapy, or both sets of mammograms and were included in this study. Of 106 women, 31 (29 %) had invasive ductal carcinoma (IDC) and 60 (57 %) had both IDC and ductal carcinoma in situ (DCIS). Microcalcifications decreased or remained stable in 76 (72 %) patients after completion of NAC. Correlation of microcalcifications with histopathology after NAC showed that 43 (40.6 %) patients had tumors associated with benign pathology. Of 32 patients with pathologic complete response, calcifications were associated with DCIS in 9 (9 %) and benign findings in 21 (22 %). The proportion of residual malignant calcifications was higher in ER+ versus ER- patients after NAC. CONCLUSIONS: The extent of calcifications on mammography following NAC does not correlate with the extent of residual disease in up to 22 % of women; this information may impact surgical planning in subsets of women with breast cancer.

Interpretation time of computer-aided detection at screening mammography.

PURPOSE: To prospectively determine the interpretation time associated with computer-aided detection (CAD) and to analyze how CAD affected radiologists' decisions and their level of confidence in their interpretations of digital screening mammograms. MATERIALS AND METHODS: An Institutional Review Board exemption was obtained, and patient consent was waived in this HIPAA compliant study. The participating radiologists gave informed consent. Five radiologists were prospectively studied as they interpreted 267 clinical digital screening mammograms. Interpretation times, recall decisions, and confidence levels were recorded without CAD and then with CAD. Software was used for linear regression fitting of interpretation times. P values less than .05 were considered to indicate statistically significant differences. RESULTS: Mean interpretation time without CAD was 118 seconds ± 4.2 (standard error of the mean). Mean time for reviewing CAD images was 23 seconds ± 1.5. CAD identified additional findings in five cases, increased confidence in 38 cases, and decreased confidence in 21 cases. Interpretation time without CAD increased with the number of mammographic views (P < .0001). Mean times for interpretation without CAD and review of the CAD images both increased with the number of CAD marks (P < .0001). The interpreting radiologist was a significant variable for all interpretation times (P < .0001). Interpretation time with CAD increased by 3.2 seconds (95% confidence interval: 1.8, 4.6) for each calcification cluster marked and by 7.3 seconds (95% confidence interval: 4.7, 9.9) for each mass marked. CONCLUSION: The additional time required to review CAD images represented a 19% increase in the mean interpretation time without CAD. CAD requires a considerable time investment for digital screening mammography but may provide less measureable benefits in terms of confidence of the radiologists.