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

Abstract

BackgroundApproximately 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.MethodsRetrospective 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.ResultsOf 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).ConclusionsThe 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 registrationRetrospective study design, waived by the IRB.

Breast Lesions of Uncertain Malignant Potential (B3) and the Risk of Breast Cancer Development: A Long-Term Follow-Up Study

“…ADH histotype showed the highest upgrade risk (39.8%), followed by PLs (24.4%) and LIN (19.9%); the upgrade rates were concordant with data from the literature for ADH [14] and LIN [5,15,16], whereas the upgrade rate for PLs was slightly lower [17]. However, to our knowledge, there are no recent studies or meta-analyses on the upgrade rate of atypical papillary lesions, so we assume that this difference may be due to the better visualization of PLs thanks to improvements in US technology and better sampling with needles of larger caliper in more recent years [18].…”

B3 lesion upgrade rates in a tertiary Australian breast centre: a 8‐year experience (2012–2019)

“…ADH and papillary lesions with atypia) in our cohort was comparable to other international studies. 3,8,9,[12][13][14][15][16][17][18][19][20] Given the consistency of high upgrade rates, we believe standard open surgical excisional biopsy should be performed for ADH and papillary lesions with atypia.…”

A simplified scoring protocol to improve diagnostic accuracy with the breast imaging reporting and data system in breast magnetic resonance imaging

“…Ideally, threelevel differentiation is recommended, with malignant, risk, and benign lesions corresponding to category 5, category 4, and category 3 or lower, respectively. The management of category 4 lesions depends on localization-if the lesions are local, then a biopsy is recommended; otherwise, a shortterm follow-up should be suggested (44).…”