What is the best next step for a 50-year-old female with a pathology report showing flat epithelial atypia and focal atypical ductal hyperplasia after a stereotactic biopsy of the left breast?

From the Guidelines

The best next step for a 50-year-old female with flat epithelial atypia and focal atypical ductal hyperplasia on stereotactic biopsy of the left breast is surgical excision of the area. This recommendation is based on the fact that both flat epithelial atypia and atypical ductal hyperplasia are high-risk lesions that can be associated with concurrent malignancy not sampled by the initial biopsy, as noted in studies such as 1. The surgical excision should be performed as a diagnostic excisional biopsy, typically as an outpatient procedure under local anesthesia with sedation. The surgeon will remove the entire area of concern with a margin of normal tissue, guided by the placement of a localization wire or radioactive seed before surgery if the lesion is not palpable. Some key points to consider in the management of such lesions include:

• The potential for upgrade to ductal carcinoma in situ or invasive breast cancer upon surgical excision, which has been reported in approximately 10-30% of atypical ductal hyperplasia diagnosed on core biopsy 2.
• The importance of continued routine breast cancer screening with annual mammography following excision.
• The potential benefit of discussing chemoprevention options, such as tamoxifen or raloxifene, to reduce future breast cancer risk, depending on the patient's risk factors. It's also worth noting that while there may be variability in the follow-up interval based on the level of suspicion, surgical excision is generally recommended for atypical ductal hyperplasia, as stated in guidelines such as those from the National Comprehensive Cancer Network 2. However, select patients with lesions like flat epithelial atypia may be suitable for monitoring in lieu of surgical excision, but this should be decided on a case-by-case basis, considering factors such as the patient's overall risk profile and preferences. In any case, the management of high-risk breast lesions should be individualized and may involve a multidisciplinary approach, including discussion among radiologists, pathologists, surgeons, and medical oncologists, as suggested by studies and guidelines like 1, 3, 4.

From the Research

Diagnosis and Recommendations

The patient's pathology report shows flat epithelial atypia and focal atypical ductal hyperplasia with associated microcalcifications. Considering the evidence from various studies, the following points are relevant:

• A study published in 2015 5 found that the upgrade rate to invasive carcinoma or ductal carcinoma in situ in excision specimens following a diagnosis of pure flat epithelial atypia on core biopsy is relatively low, especially when all calcifications are removed by the stereotactic core biopsy.
• Another study from 2012 6 reported that the incidence of carcinoma in the flat epithelial atypia + atypical ductal hyperplasia group is significantly higher than in the pure flat epithelial atypia group.
• Research from 2018 7 suggests that atypical ductal hyperplasia may not require surgical excision in certain cases, such as when there is no mass lesion or discordance, and a significant percentage of calcifications are removed during the core needle biopsy.

Management Options

Based on the evidence, the following management options can be considered:

• Surgical excision may not be necessary for patients with flat epithelial atypia and atypical ductal hyperplasia if all calcifications are removed during the stereotactic core biopsy, and there are no other high-risk features present 5, 8.
• Close clinical and mammographic follow-up may be a reasonable approach for patients with pure flat epithelial atypia, especially if the lesion is small and completely removed at biopsy 6, 9.
• A multidisciplinary approach should be taken to consider all patient, radiologic, clinical, and histopathologic factors when deciding on the best course of management 9.

Key Considerations

Some key considerations in managing this patient's case include:

• The extent of calcification removal during the stereotactic core biopsy
• The presence of any additional high-risk features, such as a family history of breast cancer or genetic mutations
• The patient's overall breast cancer risk profile
• The potential benefits and risks of surgical excision versus close surveillance 5, 6, 7, 9, 8