Review on current treatment options for lesions of uncertain malignant potential (B3 lesions) of the breast: do B3 papillary lesions need to be removed in any case by open surgery?

Breast lesions excised via vacuum-assisted system: could we get any clues for B3 lesions before excision biopsy?

Background

The purpose of this study was to determine the validity of the ultrasound features as well as patient characteristics assigned to B3 (uncertain malignant potential) breast lesions before vacuum-assisted excision biopsy (VAEB).

Methods

This study population consisted of 2245 women with breast-nodular abnormalities, which were conducted ultrasound-guided VAEB (US-VAEB). Patient’s clinical and anamnestic data and lesion-related ultrasonic feature variables of B3 captured before US-VAEB were compared with those of benign or malignant cases, using histopathological results as a benchmark.

Results

The proportions of benign, B3 and malignant breast lesions diagnosed post-US-VAEB were 88.5, 8.2 and 3.4% respectively. B3 high frequent occurred in BI-RADS-US grade 3 (7.7%), grade 4a (11.0%) and grade 4b (9.1%). The overall malignancy underestimation rate of B3 was 4.4% (8/183). Malignant lesions were found mostly in the range of BI-RADS grade 4b (27.3%), grade 4c (33.3%) and grade 5 (100%). Multivariate binary logistic regression analyses (B3 vs benign) showed that non-menopausal patients (95% CI 1.628–8.616, P = 0.002), single (95% CI 1.370–2.650, P = 0.000) or vascularity (95% CI 1.745–4.150, P = 0.000) nodules in ultrasonic features were significant risk factors for B3 occurrences. In addition, patients elder than 50 years (95% CI 3.178–19.816, P = 0.000), unclear margin (95% CI 3.571–14.119, P = 0.000) or suspicious calcification (95% CI 4.010–30.733, P = 0.000) lesions were significantly associated with higher risks of malignant potentials for B3 cases (malignant vs B3).

Conclusion

The results of this study indicate that ultrasound findings and patients’ characteristics might provide valuable information for distinguishing B3 lesions from benign breast abnormalities before VAEB, and help to reduce malignancy underestimation of B3.

Papillary lesions of the breast: a review

Papillary breast lesions are rare breast tumors that comprise a broad spectrum of diseases. Pathologically they present as mass-like projections attached to the wall of the ducts, supported by fibrovascular stalks lined by epithelial cells. On mammogram they appear as masses that can be associated with microcalcifications. Ultrasound is the most used imaging modality. On ultrasound papillary lesions appear as homogeneous solid lesions or complex intracystic lesions. A nonparallel orientation, an echogenic halo or posterior acoustic enhancement associated with microcalcifications are highly suggestive of malignancy. MRI has proven to be useful to establish the extent of the lesion. Core needle biopsy is the gold standard for diagnosis. Surgical excision is usually recommended, although treatment for papillomas without atypia is still controversial.

The Incidence of Adjacent Synchronous Invasive Carcinoma and/or Ductal Carcinoma In Situ in Patients with Intraductal Papilloma without Atypia on Core Biopsy: Results from a Prospective Multi-Institutional Registry (TBCRC 034)

BACKGROUND

Available retrospective data suggest the upgrade rate for intraductal papilloma (IP) without atypia on core biopsy (CB) ranges from 0 to 12%, leading to variation in recommendations. We conducted a prospective multi-institutional trial (TBCRC 034) to determine the upgrade rate to invasive cancer (IC) or ductal carcinoma in situ (DCIS) at excision for asymptomatic IP without atypia on CB.

METHODS

Prospectively identified patients with a CB diagnosis of IP who had consented to excision were included. Discordant cases, including BI-RADS > 4, and those with additional lesions requiring excision were excluded. The primary endpoint was upgrade to IC or DCIS by local pathology review with a predefined rule that an upgrade rate of ≤ 3% would not warrant routine excision. Sample size and confidence intervals were based on exact binomial calculations. Secondary endpoints included diagnostic concordance for IP between local and central pathology review and upgrade rates by central pathology review.

RESULTS

The trial included116 patients (median age 56 years, range 24-82) and the most common imaging abnormality was a mass (n = 91, 78%). Per local review, 2 (1.7%) cases were upgraded to DCIS. In both of these cases central pathology review did not confirm DCIS on excision. Additionally, central pathology review confirmed IP without atypia in core biopsies of 85/116 cases (73%), and both locally upgraded cases were among them.

CONCLUSION

In this prospective study of 116 IPs without atypia on CB, the upgrade rate was 1.7% by local review, suggesting that routine excision is not indicated for IP without atypia on CB with concordant imaging findings.

Benign Breast Tumours - Diagnosis and Management

With improvements in breast imaging, mammography, ultrasound and minimally invasive interventions, the detection of early breast cancer, non-invasive cancers, lesions of uncertain malignant potential, and benign lesions has increased. However, with the improved diagnostic capabilities comes a substantial risk of false-positive benign lesions and vice versa false-negative malignant lesions. A statement is provided on the manifestation, imaging, and diagnostic verification of isolated benign breast tumours that have a frequent manifestation, in addition to general therapy management recommendations. Histological evaluation of benign breast tumours is the most reliable diagnostic method. According to the S3 guideline and information gained from analysis of the literature, preference is to be given to core biopsy for each type of tumour as the preferred diagnostic method. An indication for open biopsy is also to be established should the tumour increase in size in the follow-up interval, after recurring discrepancies in the vacuum biopsy results, or at the request of the patient. As an alternative, minimally invasive procedures such as therapeutic vacuum biopsy, cryoablation or high-intensity focused ultrasound are also becoming possible alternatives in definitive surgical management. The newer minimally invasive methods show an adequate degree of accuracy and hardly any restrictions in terms of post-interventional cosmetics so that current requirements of extensive breast imaging can be thoroughly met.