Special Types of Breast Cancer: Clinical Behavior and Radiological Appearance.

Breast cancer is a complex disease that includes entities with different characteristics, behaviors, and responses to treatment. Breast cancers are categorized into subgroups based on histological type and grade, and these subgroups affect clinical presentation and oncological outcomes. The subgroup of "special types" encompasses all those breast cancers with insufficient features to belong to the subgroup "invasive ductal carcinoma not otherwise specified". These cancers account for around 25% of all cases, some of them having a relatively good prognosis despite high histological grade. The purpose of this paper is to review and illustrate the radiological appearance of each special type, highlighting insights and pitfalls to guide breast radiologists in their routine work.

Budget impact analysis of introducing digital breast tomosynthesis in breast cancer screening in Italy.

PURPOSE: This study quantifies the impact on budget and cost per health benefit of implementing digital breast tomosynthesis (DBT) in place of digital mammography (DM) for breast cancer screening among asymptomatic women in Italy. METHODS: A budget impact analysis and a cost consequence analysis were conducted using parameters from the MAITA project and literature. The study considered four scenarios for DBT implementation, i.e., DBT for all women, DBT for women aged 45-49 years, DBT based on breast density (BI-RADS C + D or D only), and compared these to the current DM screening. Healthcare provider's perspective was adopted, including screening, diagnosis, and cancer treatment costs. RESULTS: Introducing DBT for all women would increase overall screening costs by 20%. Targeting DBT to women aged 45-49 years or with dense breasts would result in smaller cost increases (3.2% for age-based and 1.4-10.7% for density-based scenarios). The cost per avoided interval cancer was significantly higher when DBT was applied to all women compared to targeted approaches. The cost per gained early-detected cancer slightly increases in targeted approaches, while the assumptions on the clinical significance and overdiagnosis of cancers detected by DBT and not by DM have a strong impact. CONCLUSIONS: Implementing DBT as a primary breast cancer test in screening programs in Italy would lead to a substantial increase in costs. Tailoring DBT use to women aged 45-49 or with dense breasts could enhance the feasibility and sustainability of the intervention. Further research is needed to clarify the impact of DBT on overdiagnosis and the long-term outcomes.

Organizational impact of systemic implementation of digital breast tomosynthesis as a primary test for breast cancer screening in Italy.

PURPOSE: We present a comprehensive investigation into the organizational, social, and ethical impact of implementing digital breast tomosynthesis (DBT) as a primary test for breast cancer screening in Italy. The analyses aimed to assess the feasibility of DBT specifically for all women aged 45-74, women aged 45-49 only, or those with dense breasts only. METHODS: Questions were framed according to the European Network of Health Technology Assessment (EuNetHTA) Screening Core Model to produce evidence for the resources, equity, acceptability, and feasibility domains of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) decision framework. The study integrated evidence from the literature, the MAITA DBT trials, and Italian pilot programs. Structured interviews, surveys, and systematic reviews were conducted to gather data on organizational impact, acceptability among women, reading and acquisition times, and the technical requirements of DBT in screening. RESULTS: Implementing DBT could significantly affect the screening program, primarily due to increased reading times and the need for additional human resources (radiologists and radiographers). Participation rates in DBT screening were similar, if not better, to those observed with standard digital mammography, indicating good acceptability among women. The study also highlighted the necessity for specific training for radiographers. The interviewed key persons unanimously considered feasible tailored screening strategies based on breast density or age, but they require effective communication with the target population. CONCLUSIONS: An increase in radiologists' and radiographers' workload limits the feasibility of DBT screening. Tailored screening strategies may maximize the benefits of DBT while mitigating potential challenges.

Comparing accuracy of tomosynthesis plus digital mammography or synthetic 2D mammography in breast cancer screening: baseline results of the MAITA RCT consortium.

AIM: The analyses here reported aim to compare the screening performance of digital tomosynthesis (DBT) versus mammography (DM). METHODS: MAITA is a consortium of four Italian trials, REtomo, Proteus, Impeto, and MAITA trial. The trials adopted a two-arm randomised design comparing DBT plus DM (REtomo and Proteus) or synthetic-2D (Impeto and MAITA trial) versus DM; multiple vendors were included. Women aged 45 to 69 years were individually randomised to one round of DBT or DM. FINDINGS: From March 2014 to February 2022, 50,856 and 63,295 women were randomised to the DBT and DM arm, respectively. In the DBT arm, 6656 women were screened with DBT plus synthetic-2D. Recall was higher in the DBT arm (5·84% versus 4·96%), with differences between centres. With DBT, 0·8/1000 (95% CI 0·3 to 1·3) more women received surgical treatment for a benign lesion. The detection rate was 51% higher with DBT, ie. 2·6/1000 (95% CI 1·7 to 3·6) more cancers detected, with a similar relative increase for invasive cancers and ductal carcinoma in situ. The results were similar below and over the age of 50, at first and subsequent rounds, and with DBT plus DM and DBT plus synthetic-2D. No learning curve was appreciable. Detection of cancers >= 20 mm, with 2 or more positive lymph nodes, grade III, HER2-positive, or triple-negative was similar in the two arms. INTERPRETATION: Results from MAITA confirm that DBT is superior to DM for the detection of cancers, with a possible increase in recall rate. DBT performance in screening should be assessed locally while waiting for long-term follow-up results on the impact of advanced cancer incidence.

Atypical ductal hyperplasia on vacuum-assisted breast biopsy: a scoring system to predict the risk of upgrade to malignancy.

RATIONALE AND OBJECTIVES: Our multicentric study analysed clinical, radiologic and pathologic features in patients with atypical ductal hyperplasia (ADH) diagnosed with vacuum-assisted biopsy (VAB), to identify factors associated with the risk of upgrade, to develop a scoring system to support decision making. MATERIALS AND METHODS: Patients with ADH on VAB under stereotactic/tomosynthesis guidance (2012-2022) were eligible. Inclusion criteria were availability of surgical histopathological examination of the entire lesion or radiologic follow-up (FUP) ≥ 24 months. VAB results were compared with surgical pathological results or with imaging FUP evolution to assess upgrade. A backward stepwise linear regression was used to identify predictors of upgrade. The discriminatory power of the model was calculated through the area under the receiver operating curve (ROC-AUC); the Hosmer-Lemeshow test was used to assess model calibration. The points system was developed based on the selected risk factors, and the probability of upgrade associated with each point total was determined. RESULTS: 112 ADH lesions were included: 91 (91/112, 81.3%) underwent surgical excision with 20 diagnosis of malignancy, while 21 (21/112, 18.7%) underwent imaging FUP with one interval change (mean FUP time 48 months). Overall upgrade rate was 18.7% (21/112). Age, menopausal status, concurrent breast cancer, BIRADS classification and number of foci of ADH were identified as risk factors for upgrade. Our model showed an AUC = 0.85 (95% CI 0.76-0.94). The points system showed that the risk of upgrade is < 2% when the total score is ≤ 1. CONCLUSION: Our scoring system seemed a promising easy-to-use decision support tool for management of ADH, decreasing unnecessary surgeries, reducing patients' overtreatment and healthcare costs.

Angiosarcoma of the Breast: Overview of Current Data and Multimodal Imaging Findings.

Angiosarcoma of the breast is a rare breast cancer, which can arise de novo (primary breast angiosarcoma, PBA) or as a secondary malignancy (secondary breast angiosarcoma, SBA) as a result of a biological insult. In the latter case, it is usually diagnosed in patients with a previous history of radiation therapy following a conserving treatment for breast cancer. Over the years, the advances in early diagnosis and treatment of breast cancer, with increasing use of breast-conserving surgery and radiation therapy (instead of radical mastectomy), brought about an increased incidence of the secondary type. PBA and SBA have different clinical presentations and often represent a diagnostic challenge due to the nonspecific imaging findings. The purpose of this paper is to review and describe the radiological features of breast angiosarcoma, both in conventional and advanced imaging to guide radiologists in the diagnosis and management of this rare tumor.

Tomosynthesis-Detected Architectural Distortions: Correlations between Imaging Characteristics and Histopathologic Outcomes.

OBJECTIVE: to determine the positive predictive value (PPV) of tomosynthesis (DBT)-detected architectural distortions (ADs) and evaluate correlations between AD's imaging characteristics and histopathologic outcomes. METHODS: biopsies performed between 2019 and 2021 on ADs were included. Images were interpreted by dedicated breast imaging radiologists. Pathologic results after DBT-vacuum assisted biopsy (DBT-VAB) and core needle biopsy were compared with AD detected by DBT, synthetic2D (synt2D) and ultrasound (US). RESULTS: US was performed to assess a correlation for ADs in all 123 cases and a US correlation was identified in 12/123 (9.7%) cases, which underwent US-guided core needle biopsy (CNB). The remaining 111/123 (90.2%) ADs were biopsied under DBT guidance. Among the 123 ADs included, 33/123 (26.8%) yielded malignant results. The overall PPV for malignancy was 30.1% (37/123). The imaging-specific PPV for malignancy was 19.2% (5/26) for DBT-only ADs, 28.2% (24/85) for ADs visible on DBT and synth2D mammography and 66.7% (8/12) for ADs with a US correlation with a statistically significant difference among the three groups (p = 0.01). CONCLUSIONS: DBT-only ADs demonstrated a lower PPV of malignancy when compared with syntD mammography, and DBT detected ADs but not low enough to avoid biopsy. As the presence of a US correlate was found to be related with malignancy, it should increase the radiologist's level of suspicion, even when CNB returned a B3 result.

Lobular Breast Cancer Conspicuity on Digital Breast Tomosynthesis Compared to Synthesized 2D Mammography: A Multireader Study.

OBJECTIVES: To compare the conspicuity of lobular breast cancers at digital breast tomosynthesis (DBT) versus synthesized 2D mammography (synt2D). MATERIALS AND METHODS: Seventy-six women (mean age 61.2 years, range 50-74 years) submitted to biopsy in our institution, from 2019 to 2021, with proven invasive lobular breast cancer (ILC) were enrolled in this retrospective study. The participants underwent DBT and synt2D. Five breast radiologists, with different years of experience in breast imaging, independently assigned a conspicuity score (ordinal 6-point scale) to DBT and synt2D. Lesion conspicuity was compared, for each reader, between the synt2D overall conspicuity interpretation and DBT overall conspicuity interpretation using a Wilcoxon matched pairs test. RESULTS: A total of 50/78 (64%) cancers were detected on both synt2D and DBT by all the readers, while 28/78 (26%) cancers where not recognized by at least one reader on synt2D. For each reader, in comparison with synt2D, DBT increased significantly the conspicuity of ILC (p < 0.0001). The raw proportion of high versus low conspicuity by modality confirmed that cancers were more likely to have high conspicuity at DBT than synt2D. CONCLUSIONS: ILCs were more likely to have high conspicuity at DBT than at synt2D, increasing the chances of the detection of ILC breast cancer.

Low-grade adenosquamous carcinoma of the breast: a review with focus on imaging and management.

Low-grade adenosquamous carcinoma is a less frequent variant of metaplastic breast carcinoma, incidentally detected during screening and has an age distribution similar to other breast carcinomas. It shares characteristics with both benign and malignant carcinomas: its mammographic and sonographic features are therefore nonspecific. Breast conserving surgery with adjuvant radiation therapy is currently the preferred therapeutic approach. The aim of this review is to describe the imaging and clinical features of low-grade adenosquamous carcinoma for appropriate identification and diagnosis. The associated pitfalls, histopathologic and epidemiologic factors, natural course, and management of low-grade adenosquamous carcinoma are also discussed.

Diagnostic accuracy of resection margin in specimen radiography: digital breast tomosynthesis versus full-field digital mammography.

OBJECTIVE: We investigated the accuracy of digital breast tomosynthesis compared to full-field digital mammography for evaluating tumor-free resection margins in the intraoperative specimen during breast-conserving surgery, reducing re-excision rates. MATERIALS AND METHODS: In total, 170 patients, with proven breast cancer and eligible for breast-conserving surgery, were enrolled. Intraoperative specimens underwent digital mammography and digital breast tomosynthesis. Two breast radiologists, with ten years of experience in breast imaging, in batch mode, evaluated tumor-free resection margins and the distance between the margins and lesion. Histopathological findings were considered the standard of reference. RESULTS: We used the correlation analysis to evaluate the agreement between measures of tumor-free resection margins obtained with digital mammography and the true value (histopathological findings), and between digital breast tomosynthesis and histopathological findings. The size evaluation determined by digital breast tomosynthesis was more accurately correlated with that found by pathology; the calculated Pearson's correlation coefficient of digital breast tomosynthesis and digital mammography to the pathologically determined tumor-free resection margins were 0.92 and 0.79 in CC view and 0.92 and 0.72 in LL view, respectively. Compared with the pathologically determined tumor-free resection margins, the size determined by both imaging modalities was, on average, overestimated. Bland-Altman analysis showed an excellent inter readers agreement. CONCLUSIONS: Digital breast tomosynthesis is more accurate in assessment of margin status than digital mammography; it could be a more accurate technique than full-field digital mammography for the intraoperative delineating of tumor resection margins.

Anomalous right coronary artery origin from pulmonary artery associated with aortic stenosis, mitral regurgitation, and Vieussens' arterial ring: a very rare association and case.

We report a very rare case of anomalous origin of the right coronary artery from the pulmonary artery associated with severe aortic stenosis, severe mitral regurgitation, and Vieussens' arterial ring (VAR). Diagnosis was made accidentally during preoperative coronary angiography and confirmed by multidetector computed tomography. Surgery was performed with aortic valve replacement, mitral valve annuloplasty, right coronary artery reimplantation into the ascending aorta, and VAR resection. .

Diffusion-weighted magnetic resonance imaging in the characterization of axillary lymph nodes in patients with breast cancer.

PURPOSE: To assess prospectively the accuracy of diffusion-weighted magnetic resonance imaging (DWI) in differentiating between metastatic and benign axillary lymph nodes in patients with breast cancer. MATERIALS AND METHODS: In all, 215 patients with histologically proven breast cancer, prior to axillary dissection, underwent breast and axillary 1.5 T MRI. In 102 patients in whom at least one axillary lymph node with a short axis of 6 mm or more was found the apparent diffusion coefficient (ADC) was measured in one lymph node per patient by means of an echo planar, parallel imaging DWI sequence. Forty-three lymph nodes were finally included which, on histological examination, either contained a metastasis larger than 5 mm or were metastasis-free; nodes with metastases smaller than 5 mm were excluded. RESULTS: From histological examination, 19/43 lymph nodes had a metastasis at least 5 mm, while in 24/43 no malignant cells were found. The ADC values of the lymph nodes with metastases (mean: 0.878 × 10(-3) mm(2) /s; range: 0.30 -1.20) were significantly lower (P < 0.001) than those of the benign lymph nodes (mean: 1.494; range: 0.60 -2.50). Adopting a threshold value of 1.09 × 10(-3) mm(2) /s DWI resulted in 94.7% sensitivity, 91.7% specificity, and 93.0% accuracy in the identification of metastasis in this series of lymph nodes. CONCLUSION: From these preliminary data DWI seems a promising method in the differential diagnosis between metastatic and benign axillary lymph nodes in patients with breast cancer.

Diffusion-weighted magnetic resonance imaging of the normal endometrium: temporal and spatial variations of the apparent diffusion coefficient.

BACKGROUND: Diffusion-weighted magnetic resonance imaging (DWI) is increasingly used in the diagnosis of endometrial disease. No complete knowledge, however, exists yet of the influence of physiology on the endometrial apparent diffusion coefficient (ADC) values on which DWI is based. PURPOSE: To establish whether the ADC values measured with DWI in the endometrium of healthy reproductive-aged women significantly vary from the early proliferative to the periovulatory phase of the menstrual cycle and between the fundus and the isthmus of the uterus. MATERIAL AND METHODS: In 17 women the endometrial ADC values measured on the fifth menstrual day, both at the fundus and at the isthmus of the uterus, were compared to the values obtained on the 14th day before the subsequent cycle. In 81 women (menstrual day: fifth through 21st) the endometrial ADC values measured at the fundus were compared to the values obtained at the isthmus of the uterus. All examinations were performed with a 1.5 T magnet (b values: 0 and 800 mm/s(2)). The results were analyzed by means of Student's t-test per paired data. RESULTS: The endometrial ADC values measured on the fifth day of the menstrual cycle were lower than those obtained in the periovulatory phase both at the fundus (mean 0.923 vs. 1.256 × 10(-3) mm(2)/s) and at the isthmus (mean 1.297 vs. 1.529 × 10(-3) mm(2)/s) of the uterus. The endometrial ADC values measured at the fundus of the uterus were lower than those obtained at the isthmus (mean 1.132 vs. 1.420 × 10(-3) mm(2)/s) through the menstrual cycle. All these differences were highly significant (P < 0.001) at statistical analysis. CONCLUSION: Physiological variations occurring in endometrial ADC values of healthy women should be considered by the radiologists when interpreting DWI examinations in patients with endometrial disease.

Diffusion-weighted Magnetic Resonance Imaging: What Makes Water Run Fast or Slow?

Diffusion-Weighted Magnetic Resonance Imaging (DWI) obtains information useful in diagnosing several diseases through the measurement of random, Brownian diffusion of water molecules in tissues. This pictorial essay illustrates the main factors, i.e., ratio between the volume occupied by cells and the extracellular space, composition of the extracellular space, and temperature, that determine the rate of the water diffusion. The mechanism through which these influencing factors affect water diffusion is explained. Clinical and experimental examples, derived both from physiology and from non-human models, are described.

Role of Magnetic Resonance Enterography in Differentiating between Fibrotic and Active Inflammatory Small Bowel Stenosis in Patients with Crohn's Disease.

OBJECTIVE: To assess the diagnostic accuracy of magnetic resonance imaging (MRI) in prospectively differentiating between fibrotic and active inflammatory small bowel stenosis in patients with Crohn's disease (CD). MATERIALS AND METHODS: A total of 111 patients with histologically proven CD presenting with clinical and plain radiographic signs of small bowel obstruction underwent coronal and axial MRI scans after oral administration of polyethylene glycol solution. A stenosis was judged present if a small bowel segment had >80% lumen reduction as compared to an adjacent normal loop and mural thickening of >3 mm. At the level of the stenosis, both T2 signal intensity and post-gadolinium T1 enhancement were quantified using a 5-point scale (0: very low; 1: low; 2: moderate; 3: high; and 4: very high). A stenosis was considered fibrotic if the sum of the two values (activity score: AS) did not exceed 1. RESULTS: A small bowel stenosis was identified in 48 out of 111 patients. Fibrosis was confirmed at histology in all of the 23 patients with AS of 0 or 1, who underwent surgery within 3 days of the MRI examination. In the remaining 25 patients (AS: 2-8), an active inflammatory stenosis was suspected and remission of the obstructive symptoms was obtained by means of medical treatment. One of these patients (AS: 2), however, underwent surgery after 14 days, due to recurrence. MRI had 95.8% sensitivity, 100% specificity, and 97.9% accuracy in the diagnosis of fibrotic stenosis. CONCLUSION: MRI is reliable in differentiating fibrotic from inflammatory small bowel stenosis in CD.

Soft-Tissue Localization of Hepatoid Adenocarcinoma: First Case Report.

Hepatoid adenocarcinoma (HAC) is a rare type of extrahepatic cancer, whose pathologic features are indistinguishable from those of hepatocellular carcinoma. About thirty cases, nearly half of which occurring in the lung, have been described in patients with a normal liver. No imaging features are typical enough to allow a correct diagnosis. A localization of HAC in the soft tissues of the shoulder with invasion of the scapula in a woman without other symptoms is reported in this paper; soft-tissue HACs have never been described to date. An associate pulmonary HAC was eventually found in this patient.