Screening and diagnostic breast MRI: how do they impact surgical treatment? Insights from the MIPA study.

OBJECTIVES: To report mastectomy and reoperation rates in women who had breast MRI for screening (S-MRI subgroup) or diagnostic (D-MRI subgroup) purposes, using multivariable analysis for investigating the role of MRI referral/nonreferral and other covariates in driving surgical outcomes. METHODS: The MIPA observational study enrolled women aged 18-80 years with newly diagnosed breast cancer destined to have surgery as the primary treatment, in 27 centres worldwide. Mastectomy and reoperation rates were compared using non-parametric tests and multivariable analysis. RESULTS: A total of 5828 patients entered analysis, 2763 (47.4%) did not undergo MRI (noMRI subgroup) and 3065 underwent MRI (52.6%); of the latter, 2441/3065 (79.7%) underwent MRI with preoperative intent (P-MRI subgroup), 510/3065 (16.6%) D-MRI, and 114/3065 S-MRI (3.7%). The reoperation rate was 10.5% for S-MRI, 8.2% for D-MRI, and 8.5% for P-MRI, while it was 11.7% for noMRI (p ≤ 0.023 for comparisons with D-MRI and P-MRI). The overall mastectomy rate (first-line mastectomy plus conversions from conserving surgery to mastectomy) was 39.5% for S-MRI, 36.2% for P-MRI, 24.1% for D-MRI, and 18.0% for noMRI. At multivariable analysis, using noMRI as reference, the odds ratios for overall mastectomy were 2.4 (p < 0.001) for S-MRI, 1.0 (p = 0.957) for D-MRI, and 1.9 (p < 0.001) for P-MRI. CONCLUSIONS: Patients from the D-MRI subgroup had the lowest overall mastectomy rate (24.1%) among MRI subgroups and the lowest reoperation rate (8.2%) together with P-MRI (8.5%). This analysis offers an insight into how the initial indication for MRI affects the subsequent surgical treatment of breast cancer. KEY POINTS: • Of 3065 breast MRI examinations, 79.7% were performed with preoperative intent (P-MRI), 16.6% were diagnostic (D-MRI), and 3.7% were screening (S-MRI) examinations. • The D-MRI subgroup had the lowest mastectomy rate (24.1%) among MRI subgroups and the lowest reoperation rate (8.2%) together with P-MRI (8.5%). • The S-MRI subgroup had the highest mastectomy rate (39.5%) which aligns with higher-than-average risk in this subgroup, with a reoperation rate (10.5%) not significantly different to that of all other subgroups.

Preoperative breast MRI positively impacts surgical outcomes of needle biopsy-diagnosed pure DCIS: a patient-matched analysis from the MIPA study.

OBJECTIVES: To investigate the influence of preoperative breast MRI on mastectomy and reoperation rates in patients with pure ductal carcinoma in situ (DCIS). METHODS: The MIPA observational study database (7245 patients) was searched for patients aged 18-80 years with pure unilateral DCIS diagnosed at core needle or vacuum-assisted biopsy (CNB/VAB) and planned for primary surgery. Patients who underwent preoperative MRI (MRI group) were matched (1:1) to those who did not receive MRI (noMRI group) according to 8 confounding covariates that drive referral to MRI (age; hormonal status; familial risk; posterior-to-nipple diameter; BI-RADS category; lesion diameter; lesion presentation; surgical planning at conventional imaging). Surgical outcomes were compared between the matched groups with nonparametric statistics after calculating odds ratios (ORs). RESULTS: Of 1005 women with pure unilateral DCIS at CNB/VAB (507 MRI group, 498 noMRI group), 309 remained in each group after matching. First-line mastectomy rate in the MRI group was 20.1% (62/309 patients, OR 2.03) compared to 11.0% in the noMRI group (34/309 patients, p = 0.003). The reoperation rate was 10.0% in the MRI group (31/309, OR for reoperation 0.40) and 22.0% in the noMRI group (68/309, p < 0.001), with a 2.53 OR of avoiding reoperation in the MRI group. The overall mastectomy rate was 23.3% in the MRI group (72/309, OR 1.40) and 17.8% in the noMRI group (55/309, p = 0.111). CONCLUSIONS: Compared to those going directly to surgery, patients with pure DCIS at CNB/VAB who underwent preoperative MRI had a higher OR for first-line mastectomy but a substantially lower OR for reoperation. CLINICAL RELEVANCE STATEMENT: When confounding factors behind MRI referral are accounted for in the comparison of patients with CNB/VAB-diagnosed pure unilateral DCIS, preoperative MRI yields a reduction of reoperations that is more than twice as high as the increase in overall mastectomies. KEY POINTS: • Confounding factors cause imbalance when investigating the influence of preoperative MRI on surgical outcomes of pure DCIS. • When patient matching is applied to women with pure unilateral DCIS, reoperation rates are significantly reduced in women who underwent preoperative MRI. • The reduction of reoperations brought about by preoperative MRI is more than double the increase in overall mastectomies.

Magnetic resonance imaging before breast cancer surgery: results of an observational multicenter international prospective analysis (MIPA).

OBJECTIVES: Preoperative breast magnetic resonance imaging (MRI) can inform surgical planning but might cause overtreatment by increasing the mastectomy rate. The Multicenter International Prospective Analysis (MIPA) study investigated this controversial issue. METHODS: This observational study enrolled women aged 18-80 years with biopsy-proven breast cancer, who underwent MRI in addition to conventional imaging (mammography and/or breast ultrasonography) or conventional imaging alone before surgery as routine practice at 27 centers. Exclusion criteria included planned neoadjuvant therapy, pregnancy, personal history of any cancer, and distant metastases. RESULTS: Of 5896 analyzed patients, 2763 (46.9%) had conventional imaging only (noMRI group), and 3133 (53.1%) underwent MRI that was performed for diagnosis, screening, or unknown purposes in 692/3133 women (22.1%), with preoperative intent in 2441/3133 women (77.9%, MRI group). Patients in the MRI group were younger, had denser breasts, more cancers ≥ 20 mm, and a higher rate of invasive lobular histology than patients who underwent conventional imaging alone (p < 0.001 for all comparisons). Mastectomy was planned based on conventional imaging in 22.4% (MRI group) versus 14.4% (noMRI group) (p < 0.001). The additional planned mastectomy rate in the MRI group was 11.3%. The overall performed first- plus second-line mastectomy rate was 36.3% (MRI group) versus 18.0% (noMRI group) (p < 0.001). In women receiving conserving surgery, MRI group had a significantly lower reoperation rate (8.5% versus 11.7%, p < 0.001). CONCLUSIONS: Clinicians requested breast MRI for women with a higher a priori probability of receiving mastectomy. MRI was associated with 11.3% more mastectomies, and with 3.2% fewer reoperations in the breast conservation subgroup. KEY POINTS: • In 19% of patients of the MIPA study, breast MRI was performed for screening or diagnostic purposes. • The current patient selection to preoperative breast MRI implies an 11% increase in mastectomies, counterbalanced by a 3% reduction of the reoperation rate. • Data from the MIPA study can support discussion in tumor boards when preoperative MRI is under consideration and should be shared with patients to achieve informed decision-making.

Solving the preoperative breast MRI conundrum: design and protocol of the MIPA study.

Despite its high diagnostic performance, the use of breast MRI in the preoperative setting is controversial. It has the potential for personalized surgical management in breast cancer patients, but two of three randomized controlled trials did not show results in favor of its introduction for assessing the disease extent before surgery. Meta-analyses showed a higher mastectomy rate in women undergoing preoperative MRI compared to those who do not. Nevertheless, preoperative breast MRI is increasingly used and a survey from the American Society of Breast Surgeons showed that 41% of respondents ask for it in daily practice. In this context, a large-scale observational multicenter international prospective analysis (MIPA study) was proposed under the guidance of the European Network for the Assessment of Imaging in Medicine (EuroAIM). The aims were (1) to prospectively and systematically collect data on consecutive women with a newly diagnosed breast cancer, not candidates for neoadjuvant therapy, who are offered or not offered breast MRI before surgery according to local practice; (2) to compare these two groups in terms of surgical and clinical endpoints, adjusting for covariates. The underlying hypotheses are that MRI does not cause additional mastectomies compared to conventional imaging, while reducing the reoperation rate in all or in subgroups of patients. Ninety-six centers applied to a web-based call; 36 were initially selected based on volume and quality standards; 27 were active for enrollment. On November 2018, the target of 7000 enrolled patients was reached. The MIPA study is presently at the analytic phase. Key Points • Breast MRI has a high diagnostic performance but its utility in the preoperative setting is controversial. • A large-scale observational multicenter prospective study was launched to compare women receiving with those not receiving preoperative MRI. • Twenty-seven centers enrolled more than 7000 patients. The study is presently at the analytic phase.

Comparison between automated breast volume scanner (ABVS) versus hand-held ultrasound as a second look procedure after magnetic resonance imaging.

OBJECTIVES: To evaluate the agreement between automated breast volume scanner (ABVS) and conventional ultrasound (US) as a second-look (SL) tool for assessing additional findings found on MRI. METHODS: Over a 7-month period, we prospectively assigned to SL-US and SL-ABVS all patients undergoing 1.5 T breast MRI in whom additional findings were found. Five experienced breast radiologists independently interpreted SL-US and SL-ABVS in blinded sessions to evaluate the detection rate of MRI findings and assign them to BI-RADS categories. We calculated the agreement between the two methods in assessing MRI findings as significant (BI-RADS 3-5) versus not significant (BI-RADS 1-2), as well as their cancer detection rate. RESULTS: In a population of 131 patients, SL-ABVS and SL-US showed a comparable detection rate of MRI findings (69.3 vs. 71.5%) (p > 0.05; McNemar test), with an almost perfect agreement in assessing them as significant or not (k = 0.94). This translated into a comparably high cancer detection rate (83.8% for SL-ABVS vs. 87.0% for SL-US). Only 1/31 cancers was missed by SL-ABVS. CONCLUSIONS: SL-ABVS and SL-US are nearly equivalent in assessing the significance of MRI findings, leading to a comparable cancer detection rate. SL-ABVS has the potential to replace SL-US in the SL scenario. KEY POINTS: • SL-ABVS shows almost perfect agreement with SL-US in assessing MRI findings. • SL-ABVS shows a comparably high cancer detection rate with respect to SL-US. • SL-ABVS has the potential to replace SL-US in evaluating additional MRI findings.

Is there a systematic bias of apparent diffusion coefficient (ADC) measurements of the breast if measured on different workstations? An inter- and intra-reader agreement study.

OBJECTIVES: To evaluate the influence of post-processing systems, intra- and inter-reader agreement on the variability of apparent diffusion coefficient (ADC) measurements in breast lesions. METHODS: Forty-one patients with 41 biopsy-proven breast lesions gave their informed consent and were included in this prospective IRB-approved study. Magnetic resonance imaging (MRI) examinations were performed at 1.5 T using an EPI-DWI sequence, with b-values of 0 and 1000 s/mm(2). Two radiologists (R1, R2) reviewed the images in separate sessions and measured the ADC for lesion, using MRI-workstation (S-WS), PACS-workstation (P-WS) and a commercial DICOM viewer (O-SW). Agreement was evaluated using the intraclass correlation coefficient (ICC), Bland-Altman plots and coefficient of variation (CV). RESULTS: Thirty-one malignant, two high-risk and eight benign mass-like lesions were analysed. Intra-reader agreement was almost perfect (ICC-R1 = 0.974; ICC-R2 = 0.990) while inter-reader agreement was substantial (ICC from 0.615 to 0.682). Bland-Altman plots revealed a significant bias in ADC values measured between O-SW and S-WS (P = 0.025), no further systematic differences were identified. CV varied from 6.8 % to 7.9 %. CONCLUSION: Post-processing systems may have a significant, although minor, impact on ADC measurements in breast lesions. While intra-reader agreement is high, the main source of ADC variability seems to be caused by inter-reader variation. KEY POINTS: • ADC provides quantitative information on breast lesions independent from the system used. • ADC measurement using different workstations and software systems is generally reliable. • Systematic, but minor, differences may occur between different post-processing systems. • Inter-reader agreement of ADC measurements exceeded intra-reader agreement.

Foci on breast magnetic resonance imaging in high-risk women: cancer or not?

PURPOSE: To assess how frequently foci are identified on MRI in high-risk patients, and their association with malignancy, breast density, and background parenchymal enhancement (BPE). MATERIALS AND METHODS: In this multicentric study, two readers, in consensus, retrospectively reviewed screening breast MRI of 245 high-risk women, performed between 2009 and 2014. Eligible patients had at least two consecutive screening MRI, and a follow-up of at least 1 year after a lesion was first detected; histology was available for all suspicious findings. Breast density, BPE (both using BI-RADS lexicon), presence, and changes at follow-up for foci were evaluated. Clinical history of the patients was reviewed. Chi-square test was used to define significant correlations. RESULTS: 166 women (mean age 43 years), who underwent a median of 4 MRI (range 2-6) during the study period, were included. 68 foci were found in 58 women [34.9 %, 95 % confidence interval (CI) 28.1-42.5 %]. Foci were more frequent in dense breasts (P = 0.079) and with moderate or marked BPE (P < 0.001). During follow-up, two foci increased in size (2.9 %, 95 % CI 0.8-10.1 %) and at biopsy, a cancer was found (1 high-grade ductal carcinoma in situ, 1 tubular carcinoma). Breast cancer was diagnosed in the other three cases, not initially appearing as foci, and it was more frequent in women with dense breasts (P = 0.04); no correlation between cancer and BPE was found (P = 0.145). CONCLUSIONS: Foci are relatively frequent in screening MRI, and they are usually benign. An increase in size is the most reliable criteria to suspect malignancy.

Additional findings at preoperative breast MRI: the value of second-look digital breast tomosynthesis.

OBJECTIVES: To evaluate second-look digital breast tomosynthesis (SL-DBT) for additional findings (AFs) at preoperative MRI compared with second-look ultrasound (SL-US). METHODS: We included 135 patients with breast cancer who underwent digital mammography (DM), DBT, US, and MRI at two centres. MR images were retrospectively evaluated to find AFs, described as focus, mass, or non-mass; ≤10 mm or >10 mm in size; BI-RADS 3, 4, or 5. DM and DBT exams were reviewed looking for MRI AFs; data on SL-US were collected. Reference standard was histopathology or ≥12-month negative follow-up. Fisher exact test and McNemar test were used. RESULTS: Eighty-four AFs were detected in 53/135 patients (39%, 95%CI 31-48%). A correlate was found for 44/84 (52%, 95%CI 41-63%) at SL-US, for 20/84 (24%, 95%CI 11-28%) at SL-DM, for 42/84 (50%, 95%CI 39-61%) at SL-DBT, for 63/84 (75%, 95%CI 64-84%) at SL-DBT, and/or SL-US, the last rate being higher than for SL-US only, overall (p < 0.001), for mass or non-mass, ≤ or >10 mm, BI-RADS 4 or 5, or malignant lesions (p < 0.031). Of 21 AFs occult at both SLs, 17 were malignant (81%, 95%CI 58-94%). CONCLUSIONS: When adding SL-DBT to SL-US, AFs detection increased from 52% to 75%. MR-guided biopsy is needed for the remaining 25%. KEY POINTS: • Detection rate of MRI AFs using SL-US was 52% • Adding SL-DBT, the detection rate of MRI AFs significantly increased to 75%. • Over 80% of the remaining 25% MRI AFs were malignant. • MR-guided biopsy should be used when SL-US and SL-DBT are inconclusive.

Test-retest reliability of diffusion tensor imaging of the liver at 3.0 T.

PURPOSE: This study was done to evaluate test-retest reliability of liver diffusion tensor imaging (LDTI). MATERIALS AND METHODS: Ten healthy volunteers (median age 23 years) underwent two LDTI scans on a 3.0 T magnet during two imaging sessions separated by 2 weeks (session-1/-2, respectively). Fifteen gradient directions and b values of 0-1,000 s/mm(2) were used. Two radiologists in consensus assessed liver apparent diffusion coefficient (ADC) and fraction of anisotropy (FA) values on ADC and FA maps at four reference levels, namely: right upper level (RUL), right lower level (RLL), left upper level (LUL) and left lower level (LLL). We then assessed (a) whether ADC and FA values overlapped when measured on different levels within the same imaging session or between different imaging sessions; (b) the degree of variability on an intra-session and inter-session basis, respectively, using the coefficient of variation (CV). RESULTS: In sessions 1 and 2, the ADC/FA values were significantly larger in the left liver lobe (LUL/LLL) compared to right liver lobe (RUL/RLL) (p < 0.05/6). Intra-session CVs were 9.51 % (session 1) and 9.73 % (session 2) for ADC, and 12.93 % (session 1) and 11.82 % (session 2) for FA, respectively. When comparing RUL, RLL, LUL and LLL on an inter-session basis, CVs were 6.52, 8.20, 6.52 and 11.06 % for ADC, and 15.42, 15.80, 15.42 and 6.80 % for FA, respectively. CONCLUSION: LDTI provides consistent and repeatable measurements. However, since larger left lobe ADC/FA values can be attributed to artefacts, right lobe values should be considered the most reliable measurements of water diffusivity within the liver.

MR mammography using diffusion-weighted imaging in evaluating breast cancer: a correlation with proliferation index.

PURPOSE: To evaluate whether the variation of the apparent diffusion coefficient (ADC) values obtained with DWI can predict elevated levels of Ki67 proliferation index and aggressive subtypes in patients with breast cancer. MATERIALS AND METHODS: Breast MRI studies of 115 patients (mean age 57.3 years, range 36-81 years) with a biopsy-proven breast cancers were evaluated in this retrospective IRB-approved study. Examinations were performed on a 1.5 T magnet and included a Single-Shot Echoplanar DWI sequence with b values of 0 and 1000 s/mm(2). For each target lesion, ADC was measured. ADC values were compared considering Ki67 status (≥20 % or <20 %), histology, grade (G1, G2 or G3) and clinical-pathological classification (Luminal A, Luminal B HER2-positive, Luminal B HER-2 negative, HER-2 enriched and Triple Negative). Mann-Whitney U test and Kruskal-Wallis test were used for comparisons and receiver operating characteristic (ROC) curves were obtained. Inter- and intra-reader variability was evaluated in a subset of 40 patients, using interclass correlation coefficient (ICC) and Bland-Altman plots. RESULTS: Of 115 lesions, 53 (46.1 %) were assessed as Ki67 positive and 62 (53.9 %) as Ki67 negative. ADC values were significantly (p < 0.0001) lower in Ki67-positive patients (median 0.86 × 10(-3) mm(2)/s; interquartile range 0.75-0.92) compared to Ki67-negative (median 1.03 × 10(-3) mm(2)/s; interquartile range 0.92-1.13). Median ADC was also lower in G2 and G3 cancer and in the Luminal B Her2-negative subtype (p = 0.0015). No differences were found when evaluating histology. ROC curve showed a sensitivity and specificity of 83.0 and 66.1 %, respectively, when using a cutoff of 0.95 s/mm(2) to differentiate Ki67-positive from Ki67-negative cancers. Inter- and intra-reader variability was moderate (ICC = 0.623; ICC = 0.548, respectively). No systematic differences were identified with Bland-Altman plots. CONCLUSIONS: Lower ADC values are associated with elevated Ki67 proliferation index and more aggressive pathologic features. Moderate agreement in ADC measurement could be a limitation.

Comparison between different imaging techniques in the evaluation of malignant breast lesions: can 3D ultrasound be useful?

PURPOSE: This study was done to assess the feasibility of three-dimensional ultrasonography (3D-US) for volume calculation of solid breast lesions. MATERIALS AND METHODS: The volumes of 36 malignant lesions were measured using conventional 2D-US, 3D-US and magnetic resonance imaging (MRI) and compared with that obtained with histology (standard of reference). With 2D Ultrasouns, volume was estimated by measuring three diameters and calculating volume with the mathematical formula for spheres. With 3D-US, stored images were retrieved and boundaries of masses were manually outlined; volume calculation was performed with VOCAL software. For MRI, volume measurements were obtained with special software for 3D reconstructions, after each lesion had been manually outlined. Histology measured the three main diameters and the volume was estimated using the mathematical formula for spheres. Interclass correlation coefficient (ICC) and Bland-Altman plots were used to assess agreement between the volumes measured. RESULTS: ICC indicated that a good level of concordance was identified between 3D-US and histology (0.79). According to the Bland-Altman analysis, limits of agreement of mean differences of the volumes measured with the three imaging modalities were comparable with histology: -2 ÷ 1.5 cm(3) for 3D-US; -2.3 ÷ 1.3 cm(3) for 2D-US and -2.2 ÷ 1.6 cm(3) for MRI. CONCLUSIONS: 3D-US is a reliable method for the volumetric assessment of breast lesions. 3D-US is able to provide valuable information for the preoperative evaluation of lesions.

Role of magnetic resonance imaging in probably benign (BI-RADS category 3) microcalcifications of the breast.

PURPOSE: This study was undertaken to evaluate whether magnetic resonance (MR) imaging is able to rule out malignancy in the case of BI-RADS 3 microcalcifications, providing a sufficient negative predictive value (NPV) for early work-up, and to reduce unnecessary stereotactically guided vacuum-assisted biopsy (SVAB) procedures. MATERIALS AND METHODS: We prospectively enrolled consecutive women with BI-RADS 3 microcalcifications, who subsequently underwent MR imaging and SVAB. The MR studies were reviewed according to the MR-BI-RADS classification system; lesions assessed as MR-BI-RADS 1 and 2 were considered negative for malignancy, categories MR-BI-RADS 3, 4 and 5 indicated malignant lesions. The presence of additional findings was recorded. Histologic analysis and follow-up were the reference standard. MR sensitivity, specificity, positive predictive value (PPV) and NPV were calculated. RESULTS: The final population consisted of 71 lesions. Histologic analysis showed malignancy in six cases (malignancy rate 8%). At MR analysis, 60 (85%) lesions were considered negative for malignancy and 11 (15%) malignant. Additional MR imaging findings were identified in 19 (27%) patients, all corresponding to nonmalignant lesions. MR sensitivity was 33%, specificity 86%, PPV 18% and NPV 93%. CONCLUSIONS: Because of its relatively low NPV, MR imaging is not able to safely exclude malignancy in the case of BI-RADS 3 microcalcifications. The relatively high malignancy rate found in this study might support SVAB in the case of BI-RADS 3 microcalcifications.

Negative predictive value for cancer in patients with "gray-zone" PSA level and prior negative biopsy: preliminary results with multiparametric 3.0 Tesla MR.

PURPOSE: To investigate the negative predictive value (NPV) for malignancy of 3.0 Tesla (T) MRI in patients with "gray zone" PSA level and prior negative biopsies. MATERIALS AND METHODS: We enrolled 26 patients with PSA level between 2.5 and 10 ng/mL and no cancer at previous biopsies. Examinations were performed on a 3.0T system using T2-weighted imaging, diffusion-weighted imaging, spectroscopy, and postcontrast dynamic study. A regional scheme was used to record MRI findings and to perform subsequent transrectal-ultrasonography-guided biopsy. Based on the matching between imaging and biopsy findings we estimated MRI predictive values, sensitivity, specificity and accuracy on a per-patient and per-region basis. RESULTS: On a per patient basis, MRI had five true-positive (5/26; 19.2%), eight true-negative (8/26; 30.8%) and no false-negative cases, corresponding to a NPV and sensitivity of 100% each. Thirteen patients were assessed as false-positive cases (13/26; 50.0%) (specificity of 38.1%). Five of them (5/26; 19.2%) showed high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small-acinar proliferation (ASAP) at biopsy. T2-weighted imaging alone showed per-region NPV (96.8%). CONCLUSION: Because of the high NPV, MRI had the potential to avoid unnecessary biopsy in approximately one-third of "gray-zone" patients with a negative examination. Additionally, MRI was useful to address to biopsy more than one-third of patients with cancer or high-risk lesions as HGPIN and ASAP.

High-risk breast lesions at imaging-guided needle biopsy: usefulness of MRI for treatment decision.

OBJECTIVE: The purpose of this study is to evaluate the role of MRI for characterization of high-risk breast lesions diagnosed at imaging-guided needle biopsy. MATERIALS AND METHODS: In this retrospective analysis of 220 patients, 227 high-risk lesions (94 papillomas, 64 radial sclerosing lesions, 46 lobular neoplasias, and 23 atypical ductal hyperplasias) found at 11-gauge vacuum-assisted or 14-gauge needle biopsy were studied with dynamic MRI (time resolution, 84 or 88 seconds; gadopentetate dimeglumine or gadobenate dimeglumine, 0.1 mmol/kg). When lesions showed contrast enhancement on subtracted images, they were considered suspicious for malignancy. The reference standard was histopathologic examination after surgical excision in 190 of 227 (84%) lesions and negative follow-up (≥ 24 months) in 37 of 227 (16%) lesions. Predictive values and likelihood ratios were calculated. RESULTS: Of 227 lesions, 155 (68%) were contrast enhancing and 72 (32%) were not. Of 155 contrast-enhancing lesions, 28 (18%) were upgraded to malignancy after surgical excision (nine papillomas, one radial sclerosing lesion, 11 lobular neoplasias, and seven atypical ductal hyperplasias); there were 11 invasive carcinomas and 17 ductal carcinomas in situ, four of the latter being G3. Of 72 non-contrast-enhancing lesions, two (3%) were upgraded to malignancy after surgical excision (one radial sclerosing lesion and one lobular neoplasia), both of which were G1 ductal carcinoma in situ. Cancer probability was significantly higher for contrast-enhancing (18%) than for non-contrast-enhancing (3%) lesions (p = 0.001) and for nonmasslike (43%) than for masslike (14%) lesions (p = 0.005). The positive predictive value was 18% (28/155; 95% CI, 13-24%), the negative predictive value was 97% (70/72; 95% CI, 94-99%), the positive likelihood ratio was 1.448 (95% CI, 1.172-1.788), and the negative likelihood ratio was 0.188 (95% CI, 0.152-0.232). CONCLUSION: The absence of enhancement at dynamic MRI allowed reliable exclusion of invasive cancers among high-risk lesions diagnosed at needle biopsy.

Nonsurgical management of high-risk lesions diagnosed at core needle biopsy: can malignancy be ruled out safely with breast MRI?

OBJECTIVE: The purpose of this study was to investigate whether breast MRI can be used to rule out malignancy in patients with high-risk lesions diagnosed at imaging-guided core needle biopsy. SUBJECTS AND METHODS: The subjects were women consecutively registered between October 2004 and April 2010 who had high-risk lesions diagnosed at mammographically or sonographically guided core needle biopsy and subsequently underwent MRI and surgical excision. MR images were reviewed by two experienced breast radiologists. Lesions assessed as BI-RADS category 1-3 were considered negative for malignancy, and BI-RADS 4 and 5 lesions were considered malignant. Histologic findings at surgical excision were the reference standard. The sensitivity, specificity, and positive and negative predictive values of MRI in the detection of associated malignancy were calculated for the entire set of lesions and for each histologic subtype. RESULTS: The final sample consisted of 169 high-risk lesions in 166 patients. At MRI analysis, 116 (68.6%) lesions were considered negative for malignancy, and the other 53 (31.4%) malignant. At surgical excision, 22 malignant lesions were found. The overall sensitivity, specificity, and positive and negative predictive values of MRI were 72.7% (16/22), 74.8% (110/147), 30.2% (16/53), and 94.8% (110/116). The negative predictive values for papilloma, radial scar, lobular neoplasia, and atypical ductal hyperplasia were 97.4% (38/39), 97.6% (41/42), 88.0% (22/25), and 90.0% (9/10). CONCLUSION: Patients with high-risk lesions associated with the lowest likelihood of malignancy (papilloma and radial scar) and without suspicious MRI findings can safely undergo follow-up instead of surgery. Because of the low negative predictive value, however, MRI is not helpful in cases of lobular neoplasia and atypical ductal hyperplasia, and all these lesions should be excised.

Borderline breast lesions: comparison of malignancy underestimation rates with 14-gauge core needle biopsy versus 11-gauge vacuum-assisted device.

OBJECTIVE: To compare malignancy underestimation rates in the case of percutaneous diagnosis of borderline breast lesions(B3) at 14-g core-needle-biopsy (CNB) and at 11-g vacuum-assisted-biopsy (VAB). METHODS: The histological results of 4764 image-guided breast biopsies were retrospectively reviewed. 300 B3, 151 benign papillomas, 88 radial sclerosing lesions, 46 lobular neoplasia, 15 atypical ductal hyperplasia diagnosed at ultrasound-guided 14-g CNB (76%) or stereotactically-guided 11-g VAB (24%) were identified. On average, 5 cores were obtained with CNB and 12 with VAB. Biopsy variables were reviewed and correlated with surgical excision or follow-up (>24 months). Lesion- and device-specific underestimation rates of malignancy were calculated. RESULTS: Surgical excision was performed on 237 lesions: 178 were benign, 21 atypical, 38 cancers. The remaining 63 lesions were unchanged at follow-up. Overall malignancy underestimation rate was 12.7% at 14-g CNB and 12.5% at 11-g VAB. Based on excision histology or follow-up, lesion-specific underestimation rates were: benign papillomas: 14-g CNB 11%, 11-g VAB 0%; RSL: 14-g CNB 6%, 11-g VAB 4%; LN: 14-g CNB 40%, 11-g VAB 23%; ADH: 14-g CNB 33%; 11-g VAB 22%. CONCLUSION: In the case of percutaneous diagnosis of B3 lesions, underestimation of malignancy occurs regardless of the biopsy method.

Magnetic resonance imaging in patients with nipple discharge: should we recommend it?

OBJECTIVES: Comparing the sensitivity of Contrast-Enhanced Magnetic Resonance Imaging (CEMRI), mammography and ultrasonography in patients with nipple discharge (ND). METHODS: We retrospectively evaluated 38 women with ND who underwent mammography, ultrasound and 1.5 T CEMRI between March 2007 and July 2009. Imaging findings, pathological diagnosis and follow-up data (mean follow-up: 20 months) were compared. Sensitivity and specificity values were reckoned. Statistical differences in sensitivity were assessed. RESULTS: 5/38 malignancies (13.2%; 3 invasive, 2 intraductal; 4 ipsilateral, 1 contralateral to ND), and 14/38 High-Risk Lesion (HRL--36.8%; 11 intraductal papillomas, 1 papilloma with LCIS, 1 sclerosing papilloma and 1 atypical intraductal hyperplasia, all ipsilateral) were found. CEMRI identified 5/5 cancers and 13/14 HRL (Overall Sensitivity-OSS = 94.7%; Overall Specificity-OSP = 78.9%). 3/5 cancers (1 invasive, 1 in-situ; 1 invasive contralateral) and 2/14 HRL were detected by CEMRI only. Mammography found 2/5 cancer and 3/14 HRL (OSS = 26.3%; OSP = 94.7%). Ultrasound identified 1/5 cancer and 11/14 HRL (OSS = 63.2%; OSP = 84.2). 1/14 HRL was detected by ultrasound only. Compared with mammography and ultrasound, CEMRI showed statistically significantly higher OSS values (p < 0.0001, p = 0.042 respectively). CONCLUSION: In women with ND, CEMRI should be recommended when conventional imaging is negative. Unexplained ND could be considered an indication for CEMRI.

Hyperechoic lesions of the breast: not always benign.

OBJECTIVE: The purposes of our study were, first, to evaluate the frequency, clinical presentation, and associated imaging findings of malignant breast lesions presenting as hyperechoic nodules in a large series of consecutive sonographically guided core needle biopsies (CNBs) and, second, to investigate sonographic features that are able to predict malignancy in hyperechoic breast lesions. MATERIALS AND METHODS: The radiologic and pathologic records for 4511 consecutive sonographically guided CNBs were retrospectively reviewed. Hyperechoic lesions were identified, and clinical notes and related mammography or MRI reports were reviewed. The sonographic images were evaluated according to the BI-RADS lexicon by two experienced breast radiologists. Surgical pathology results and follow-up served as the reference standard for lesions diagnosed as malignant or high-risk and benign at CNB, respectively. The frequency of hyperechoic carcinomas among all carcinomas was calculated. Differences in sonographic appearance between hyperechoic benign and malignant lesions were evaluated using the chi-square test or the Fisher exact test. RESULTS: Of all biopsied lesions, 25 (0.6%) were hyperechoic. Among the 1849 malignant lesions, nine (0.4%) were hyperechoic. The remaining 16 were benign. None of the hyperechoic malignancies was a "purely" sonographic lesion, because all were palpable, mammographically visible, or detectable on breast MRI. Malignant lesions were more likely than benign lesions to have noncircumscribed margins (9/9 vs 7/16; p = 0.008) and nonparallel orientation (6/9 vs 1/16; p = 0.003). CONCLUSION: When encountering a hyperechoic nodule, malignant nature cannot be excluded. Suspicious sonographic signs and correlation with other imaging techniques may help avoid misdiagnosis.

High-performance metabolic marker assessment in breast cancer tissue by mass spectrometry.

BACKGROUND: The identification of reliable markers for diagnosis of breast cancer has been thoroughly addressed by metabolic profiling using nuclear magnetic resonance (NMR) spectroscopy or imaging. Several clear diagnostic indicators have emerged using either in vitro analysis of tissue extracts, ex vivo analysis of biopsies or in vivo direct spectral observations. Most of the breast cancer characteristic metabolites could be assayed by mass spectrometry (MS) to exploit the superior sensitivity of this technique and therefore reduce the traumatic impact of current biopsy procedures. METHODS: Following extraction, aqueous metabolite mixtures were obtained that were submitted to liquid-chromatography, electrospray-ionization, mass spectrometry (LC/ESI-MS) analysis to estimate the content of choline (Cho) and its phosphorylated derivatives, phosphocholine (PCho) and glycerophosphocholine (GPCho). The determinations were performed using 10 samples from breast tissue biopsies, surgical specimens and one single sample of a hepatic metastasis. In addition, some measurements were also repeated using high-resolution ¹H NMR spectroscopy to complement the mass spectrometry results. RESULTS: The contents of Cho, PCho and GPCho in breast tissue extracts were estimated by LC/ESI-MS based on standard compound calibration curves. Sharply increased ratios of phosphorylated-to-unphosphorylated metabolites, PCho/ Cho and (PCho+GPCho)/Cho, were observed in all tumor samples, although without discrimination between benign and malignant lesions, contrary to samples from healthy individuals and from those with fibrocystic disease. CONCLUSIONS: The assessment of breast cancer markers by LC/ESI-MS is feasible and diagnostically valuable. In addition to high sensitivity, the approach also shows a resolution advantage for assaying choline derivatives compared to NMR, and could complement the latter.

Incidental pancreatic cysts on 3D turbo spin echo magnetic resonance cholangiopancreatography: prevalence and relation with clinical and imaging features.

PURPOSE: To estimate the prevalence of incidental pancreatic cysts (IPCs) in asymptomatic patients addressed to magnetic resonance cholangiopancreatography (MRCP), and to correlate it with clinical and imaging features. MATERIALS AND METHODS: Magnetic resonance cholangiopancreatography performed over 26-months on 152 patients with unsuspected/unknown pancreatic disease were reviewed to assess IPCs' features of presentation. Multivariate analysis was performed to evaluate the correlation of IPCs with clinical information and type of pancreaticobiliary findings at MRCP. RESULTS: Prevalence of IPCs was 44.7%. Cysts sized 3-24 mm (mean, 6.08 mm), and were ≤4 in number in 83.8% of patients. Based on number, dimensions and relation with the main pancreatic duct, IPCs presented with intraductal-papillary-mucinous neoplasm (IPMN)-like or indeterminate patterns in 31.7% and 13.1% of patients, respectively. At follow-up on 24 patients, no evolution was found, except in one patient with proven IPMN showing increase in cysts number and dimensions (evolution rate of 4.1%). Features correlating with IPCs were age ≥60 years old, and history of autoimmune hepatobiliary disease, showing odds ratios of 5.95 (95% CI 2.77-12.79) and 0.13 (95% CI 0.04-0.44), respectively. CONCLUSIONS: Incidental pancreatic cysts represent a frequent finding at MRCP, correlating positively with increasing age, and negatively with biliary autoimmune disease. Cysts more frequently present with IPMN-like pattern.