Malignancy rates of B3-lesions in breast magnetic resonance imaging - do all lesions have to be excised?

BACKGROUND: Approximately 10% of all MRI-guided vacuum-assisted breast biopsies (MR-VAB) are histologically classified as B3 lesions. In most of these cases surgical excision is recommended. The aim of our study was to evaluate the malignancy rates of different B3 lesions which are visible on MRI to allow a lesion-adapted recommendation of further procedure. METHODS: Retrospective analysis of 572 consecutive MR-VAB was performed. Inclusion criteria were a representative (=successful) MR-VAB, histologic diagnosis of a B3 lesion and either the existence of a definite histology after surgical excision or proof of stability or regression of the lesion on follow-up MRI. Malignancy rates were evaluated for different histologies of B3 lesions. Lesion size and lesion morphology (mass/non-mass enhancement) on MRI were correlated with malignancy. RESULTS: Of all MR-VAB 43 lesions fulfilled the inclusion criteria. The malignancy rate of those B3 lesions was 23.3% (10/43). The highest malignancy rate was found in atypical ductal hyperplasia (ADH) lesions (50.0%; 4/8), 33.3% (2/6) in flat epithelial atypia (FEA), 28.6% (2/7) in lobular intraepithelial neoplasia (LIN) and 12.5% (2/16) in papillary lesions (PL). All 6 complex sclerosing lesions were benign. Mass findings were significantly more frequently malignant (31.3%, 10/32; p < 0.05) than non-mass findings (0/11). Small lesions measuring 5-10 mm were most often malignant (35.0%; 7/20). All large lesions (> 20 mm) were not malignant (0/10). Intermediate sized lesions (11-20 mm) turned out to be malignant in 23.1% (3/13). CONCLUSIONS: The malignancy rate of B3 lesions which were diagnosed after MR-VAB was 23.3%. ADH, FEA and LIN showed considerable malignancy rates (50%, 33% and 29%) and should therefore undergo surgical excision. None of the cases, which were diagnosed as radial scars, non-mass enhancement or larger lesions (> 20 mm) were malignant. Here, a follow-up MRI seems to be advisable to avoid unnecessary operations. TRIAL REGISTRATION: Retrospective study design, waived by the IRB.

Background parenchymal enhancement in breast MRI before and after neoadjuvant chemotherapy: correlation with tumour response.

OBJECTIVES: To correlate the decrease in background parenchymal enhancement (BPE) and tumour response measured with MRI in breast cancer patients treated with neoadjuvant chemotherapy (NAC). METHODS: One hundred and forty-six MRI examinations of 73 patients with 80 biopsy-proven breast cancers who underwent breast MRI before and after NAC were retrospectively analysed. All images were reviewed by two blinded readers, who classified BPE into categories (BEC; 1 = minimal, 2 = mild, 3 = moderate, 4 = marked) before and after NAC. Histopathological and morphological tumour responses were analysed and compared. RESULTS: The distribution of BEC 1/2/3/4 was 25/46/18/11 % before and 78/20/2/0 % after NAC. On average, BPE decreased by 0.87 BEC. Cohen's kappa showed substantial agreement (k = 0.73-0.77) before and moderate agreement (k = 0.43-0.60) after NAC and moderate agreement (k = 0.62-0.60) concerning the change in BEC. Correlating the change in BPE with tumour response, the average decrease in BEC was 1.3 in cases of complete remission, 0.83 in cases with partial response, 0.85 in cases with stable disease and 0.40 in cases with progressive disease. Correlation analysis showed a significant correlation between the decrease in BEC and tumour response (r = -0.24, p = 0.03). CONCLUSIONS: BPE decreased by, on average, 0.87 BEC following NAC for breast cancer. The degree of BPE reduction seemed to correlate with tumour response. KEY POINTS: • BPE decreases by an average of 0.87 categories under neoadjuvant chemotherapy. • The reduction of BPE following neoadjuvant chemotherapy correlates with the tumour response. • The classification of the BPE shows good agreement among trained readers.

[Digital breast tomosynthesis]. / Digitale Tomosynthese der Mamma.

In digital breast tomosynthesis several low dose mammograms are acquired from different angles to calculate thin slices of synthetic mammograms from algorithms. Similar to computed tomography and magnetic resonance imaging, breast tomosynthesis provides breast images which are virtually free from superimposition. This is in particular important in cases of high mammographic density to differentiate real masses and architectural distortions from the overlying parenchyma. In comparison to full field digital mammography tomosynthesis can improve the cancer detection rate and reduce the recall rate. The limitations of tomosynthesis are the higher radiation dose and the longer reporting time compared to full field digital mammography. Until the radiation dose can be significantly reduced it is advisable to use tomosynthesis in addition to full field digital mammography primarily for the assessment of suspicious mammographic findings and not for breast cancer screening.

Clinical value of magnetic resonance imaging in patients with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome: diagnosis of associated malformations, uterine rudiments and intrauterine endometrium.

OBJECTIVES: The aim of this study was to evaluate the accuracy of preoperative magnetic resonance imaging (MRI) in the diagnosis of malformations associated with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome and identification of uterine endometrium to optimise the clinical management. METHODS: We retrospectively reviewed 214 consecutive MRKH patients, mean age 19 years, who underwent laparoscopy-assisted neovagina creation. A total of 115 patients (53.7%) met the inclusion criterion of sufficient preoperative MRI. In 110 of them (95.7%), MRI findings were correlated with laparoscopy and associated malformations. In 39 cases (35.5%) uterine rudiments were removed and analysed histopathologically. RESULTS: Ten per cent (11/110) of the patients showed complete uterine agenesis. The others presented with either unilateral (n = 16; 14.5%) or bilateral (n = 83; 75.5%) uterine rudiments. MRI detection of uterine rudiments agreed in 78.2% (86/110) with laparoscopy. In 85.4% of the removed rudiments, MRI could correctly diagnose the existence of the endometrium. Compared to laparoscopy, MRI could exactly detect ovaries in 97.3% (107/110). Renal or ureteral malformations were seen in 32 cases (27.8%). In 83% of unilateral renal agenesis and unilateral rudiment, the latter was located at the side of the kidney. CONCLUSIONS: MRI is useful for preoperative detection of MRKH-associated malformations and assessment of the endometrium to further optimise MRKH patient treatment. KEY POINTS: • Pelvic MRI is useful for preoperative detection of MRKH-associated malformations. • MRI can diagnose uterine endometrium in MRKH patients with high precision. • Preoperative MRI can optimise clinical management of patients with MRKH syndrome.

MR imaging-guided vacuum-assisted breast biopsy: reduction of false-negative biopsies by short-term control MRI 24-48 h after biopsy.

AIM: To evaluate whether another contrast-enhanced (CE) magnetic resonance imaging (MRI) examination 24-48 h after MRI-guided vacuum-assisted breast biopsy (MRI-VAB) can reduce the rate of false-negative cases. MATERIALS AND METHODS: The study included 252 patients who underwent MRI-VAB for the clarification of 299 lesions. The success of MRI-VAB was assessed at interventional MRI and another CE MRI 24-48 h after the intervention. In cases of successful MRI-VAB (complete or partial lesion removal) and benign histological results, follow-up breast MRI was performed. In cases of unsuccessful biopsy (unchanged lesion), tissue sampling was repeated. False-negative cases were calculated to assess the diagnostic value of MRI follow-up within 2 days after intervention. RESULTS: Ninety-eight malignant (32.8%) and 201 (67.2%) benign lesions were diagnosed using MRI-VAB. At immediate unenhanced control MRI, all lesions were assessed as successfully biopsied. In 18 benign cases (6%), CE MRI after 24-48 h showed an unsuccessful intervention. Further tissue sampling revealed another 13 cancers in these patients. This results in a false-negative rate of 11.7%. Follow-up MRI of the benign lesions presented no further malignancy. CONCLUSIONS: MRI-VAB with immediate unenhanced control offers a success rate of 94%. The rate of false-negative biopsies (11.7%) could be reduced to zero by using short-term follow-up MRI. Therefore, a further CE breast MRI 24-48 h after benign MRI-VAB to eliminate missed cancers is recommended.

Preoperative breast MR Imaging in patients with primary breast cancer has the potential to decrease the rate of repeated surgeries.

PURPOSE: The impact of preoperative MRI on re-excisions and mastectomy rate is discussed controversially in the literature. Aim of this study was to evaluate the effect of preoperative breast MRI on the surgical procedure and rate of repeated surgeries. MATERIAL AND METHODS: A total of 991 consecutive patients in the years 2009 and 2010 with 1036 primary breast cancers were retrospectively analyzed. Sixty percent (599 patients with 626 cancers) received preoperative breast MRI. Planned surgical procedures before and after MRI and numbers of repeated surgeries in patients with (MR+ ) and without preoperative MRI (MR-) were compared. RESULTS: The result of preoperative MRI changed the surgical procedure in 25% (157/626) of the cases. In 81% (127/157), MRI was beneficial for the patients, as otherwise occult carcinomas were removed (n=122) or further biopsy could be prevented (n=5). Mastectomy rates did not differ between MR+ and MR- group (39% vs. 39%). On multiple regression analysis, the MR+ group had a lower chance for repeated surgery (p<0.05). CONCLUSION: Preoperative MRI could lower the chance for repeated surgery in patients with primary breast cancer. The rate of mastectomy did not differ between patients undergoing preoperative MRI and those who did not.

Management of breast lesions detectable only on MRI.

UNLABELLED: Breast MR imaging has become established as the most sensitive imaging method for diagnosing breast cancer. As a result of the increasing examination volume and improved image quality, the number of breast lesions detected only on MRI and requiring further clarification has risen in recent years. According to the S3-guideline "Diagnosis, Therapy, and Follow-Up of Breast Cancer" as revised in July 2012, institutions performing breast MRI should provide the option of an MRI-guided intervention for clarification. This review describes the indications, methods and results of MRI-guided interventions for the clarification of breast lesions only visible on MRI. Recent guidelines and study results are also addressed and alternative methods and pitfalls are presented. KEY POINTS: ▶ Up to 57 % of lesions originally visible only on MRI can be sonographically correlated and biopsied. ▶ MRI-guided intervention is necessary for the clarification of BI-RADS® 4 and 5 lesions detectable only on MRI ▶ MRI-guided vacuum-assisted breast biopsy should be preferentially used ▶ MRI-guided localization and surgical excision should be used if MRI-guided vacuum-assisted biopsy is not possible ▶ If BI-RADS® 4 and 5 findings visible only on MRI are not detectable on interventional MRI, a follow-up MRI should be performed within six months.