Role of vacuum assisted excision in minimising overtreatment of ductal atypias.

PURPOSE: B3 lesions are indeterminate lesions of uncertain malignant potential. They include lesions with and without epithelial atypia. Those with atypia include atypical intraductal epithelial proliferation (AIDEP)/atypical ductal hyperplasia (ADH) and flat epithelial atypia (FEA). They are traditionally managed with surgery. Vacuum assisted excision (VAE) allows larger samples to be obtained using a vacuum assisted biopsy (VAB) device, which equates to a surgical biopsy. We propose that VAE and mammographic surveillance is a safe alternative to surgery in managing the ductal atypias; (AIDEP/ADH and FEA). METHOD: Retrospective analysis of prospectively collected data on B3 lesions (April 2009 - March 2016) from consecutive breast screening patients diagnosed with AIDEP/ADH or FEA on initial diagnostic core biopsy. Mammographic abnormality, breast density, size, management pathway and upgrade to cancer and types of cancer were also collected during the treatment pathway and 5 year surveillance period (April 2009 - April 2019). RESULTS: 273 cases of ductal atypia were identified. 187/273 (68.5 %) cases were managed with VAE only as no upgrade to malignancy and then 5 year mammographic surveillance. 34/273 (12.5 %) cases had a VAE diagnosing malignancy. 24/273 (8.8 %) cases had a VAE and then a surgical biopsy due to radiological or pathological concern, 8/24 upgraded to malignancy. 22/273 (8%) cases had a surgical diagnostic biopsy, 9/22 (41 %) cases were upgraded to malignancy. In total 51/273 (19 %) cases were diagnosed with cancer on the new pathway (13 invasive (all ER positive and Her2 negative) and 38 non-invasive, (34 ductal carcinoma in situ (DCIS) and 4 cases of lobular carcinoma in situ (LCIS)). While 17/273 (6.2 %) cases developed malignancy (12 invasive (all HER2 negative) and 4 DCIS and 1 LCIS) during the 5 year surveillance period. CONCLUSIONS: VAE is a safe alternative to surgery in managing ductal atypias. 187/273 (68.5 %) women avoided surgery. While 34/51 cancers (66.7 %) were diagnosed preoperatively using VAE, allowing the women to have a single therapeutic procedure.

Outcome of a new patient pathway for managing B3 breast lesions by vacuum-assisted biopsy: time to change current UK practice?

AIMS: B3 lesions of the breast represent a difficult management dilemma. The umbrella term 'B3' incorporates lesions with little associated malignancy risk as well as lesions with significant risk of concurrent neoplasia. Diagnosis of B3 lesions in screening populations is largely made on needle core biopsy, which provides little tissue to adequately diagnose pathologically diverse lesions. The advent of vacuum-assisted biopsy (VAB) provides the multidisciplinary team with a more representative pathology sample to direct management. METHODS: In this unit, in 2009, a pathway to guide management of B3 lesions detected on needle core biopsy in screening patients was implemented to assess whether VAB was a safe and viable alternative to surgery in selected cases.Here we present the 5-year follow-up results of this pathway. RESULTS: 398 patients with B3 lesions were suitable for this pathway, of which 321 went on to have second-line VAB. 24% of these patients subsequently required surgery for malignancy or ongoing concerns, and thus 245 avoided surgery being subsequently referred for 5-year mammographic surveillance or back to screening. Median follow-up was 3 years (IQR 2), and no cancers were detected at the original B3 site during follow-up. CONCLUSIONS: We have demonstrated here that with large volume tissue sampling for indeterminate lesions of the breast surgery can be safely avoided in selected B3 lesions with and without atypia.

Concordance between vacuum assisted biopsy and postoperative histology: implications for the proposed Low Risk DCIS Trial (LORIS).

AIM: The recent Breast Cancer Screening Review has estimated that for one life saved three patients are overtreated. The dramatic increase in the diagnosis of Ductal carcinoma in-situ (DCIS) has not lead to the expected decrease in the incidence of invasive cancer. It is not clear if all DCIS progress to invasive cancer if untreated. The Low Risk DCIS Trial (LORIS) intends to compare the current treatment of low risk DCIS i.e. surgery, with active monitoring. For effective implementation, concordance between diagnostic biopsy using large volume vacuum assisted biopsy (VAB) and excision histology is vital. A two-centre UK audit was done to assess concordance in patients diagnosed with low grade DCIS diagnosed using VAB. METHODS: Data of DCIS diagnosed with VAB from year 2001-2010 in University Hospital Birmingham and Leeds Teaching Hospitals was retrospectively collected and concordance between diagnostic and excision histology was assessed. Low Grade DCIS diagnoses were further evaluated retrospectively with regard to their eligibility for LORIS. RESULTS: Of 225 DCIS diagnoses 128 (57%) were high grade, 66 (29%) intermediate grade and 31 (14%) low grade. Overall 18% were upgraded to invasive cancer. The upgrade rate to invasive cancer for high grade was 23% and for low grade DCIS was 10%. In the low grade group eligible for LORIS, there were no upgrades to invasive cancer. CONCLUSION: The upgrade rates to invasive cancer are comparable to series published in literature. The concordance for the low risk DCIS with zero upgrade to invasive cancer supports the stringent LORIS eligibility criteria for trial selection.