Atypical ductal hyperplasia on core needle biopsy: Development of a predictive model stratifying carcinoma upgrade risk on excision

Stromal lymphocytes are associated with upgrade of B3 breast lesions

Various histopathological, clinical and imaging parameters have been evaluated to identify a subset of women diagnosed with lesions with uncertain malignant potential (B3 or BIRADS 3/4A lesions) who could safely be observed rather than being treated with surgical excision, with little impact on clinical practice. The primary reason for surgery is to rule out an upgrade to either ductal carcinoma in situ or invasive breast cancer, which occurs in up to 30% of patients. We hypothesised that the stromal immune microenvironment could indicate the presence of carcinoma associated with a ductal B3 lesion and that this could be detected in biopsies by counting lymphocytes as a predictive biomarker for upgrade. A higher number of lymphocytes in the surrounding specialised stroma was observed in upgraded ductal and papillary B3 lesions than non-upgraded (p < 0.01, negative binomial model, n = 307). We developed a model using lymphocytes combined with age and the type of lesion, which was predictive of upgrade with an area under the curve of 0.82 [95% confidence interval 0.77-0.87]. The model can identify some patients at risk of upgrade with high sensitivity, but with limited specificity. Assessing the tumour microenvironment including stromal lymphocytes may contribute to reducing unnecessary surgeries in the clinic, but additional predictive features are needed.

Active Surveillance for Atypical Ductal Hyperplasia and Ductal Carcinoma In Situ

Atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS) are relatively common breast lesions on the same spectrum of disease. Atypical ductal hyperblasia is a nonmalignant, high-risk lesion, and DCIS is a noninvasive malignancy. While a benefit of screening mammography is early cancer detection, it also leads to increased biopsy diagnosis of noninvasive lesions. Previously, treatment guidelines for both entities included surgical excision because of the risk of upgrade to invasive cancer after surgery and risk of progression to invasive cancer for DCIS. However, this universal management approach is not optimal for all patients because most lesions are not upgraded after surgery. Furthermore, some DCIS lesions do not progress to clinically significant invasive cancer. Overtreatment of high-risk lesions and DCIS is considered a burden on patients and clinicians and is a strain on the health care system. Extensive research has identified many potential histologic, clinical, and imaging factors that may predict ADH and DCIS upgrade and thereby help clinicians select which patients should undergo surgery and which may be appropriate for active surveillance (AS) with imaging. Additionally, multiple clinical trials are currently underway to evaluate whether AS for DCIS is feasible for a select group of patients. Recent advances in MRI, artificial intelligence, and molecular markers may also have an important role to play in stratifying patients and delineating best management guidelines. This review article discusses the available evidence regarding the feasibility and limitations of AS for ADH and DCIS, as well as recent advances in patient risk stratification.

Developing Asymmetries without Sonographic Correlate at Digital Breast Tomosynthesis

Background Digital breast tomosynthesis (DBT) has improved the accuracy of mammography, including resolving many breast asymmetries as overlapping breast tissue. The pathologic outcomes of persistent developing asymmetries visualized at DBT are not well established. Purpose To characterize the outcomes and the predictors of malignancy for developing asymmetries visualized at DBT without a sonographic correlate. Materials and Methods This retrospective study included all tomosynthesis-guided biopsies of developing asymmetries performed at a single institution from May 2017 through January 2020. A reader study including three breast imaging radiologists determined interrater agreement and inclusion into the study. Electronic medical records were used to extract patient characteristics, imaging characteristics, and pathologic diagnoses. The Wilcoxon rank sum test, Fisher exact test, and χ² test were used to analyze correlations of patient and imaging characteristics with likelihood of malignancy. Results The reader study included 95 DBT examinations with moderate interrater reliability (Fleiss κ = 0.45). There was majority reader agreement in 85 of the 95 DBT examinations (89%) of 83 women (median age, 56 years; interquartile range, 47-69 years), and this finalized the study data set. At pathologic examination, most asymmetries (68 of 85, 80%) were benign, with common diagnoses being fibrocystic change (n = 20), stromal fibrosis (n = 10), and fat necrosis (n = 10). The overall malignancy rate was 20% (17 of 85 asymmetries; 95% CI: 12, 29); 15 of the 17 malignancies (88%) were invasive cancers. Malignancies were more common in women with a personal history of breast cancer (35% vs 10%, P = .02). Conclusion In 85 developing asymmetries visualized at digital breast tomosynthesis without a sonographic correlate, there was a 20% (95% CI: 12, 29) malignancy rate, which was higher than the rates of malignancy for a developing asymmetry detected at digital mammography. © RSNA, 2021 See also the editorial by Skaane in this issue.

Development and Validation of a Simple-to-Use Nomogram for Predicting the Upgrade of Atypical Ductal Hyperplasia on Core Needle Biopsy in Ultrasound-Detected Breast Lesions

Background

The rate of carcinoma upgrade for atypical ductal hyperplasia (ADH) diagnosed on core needle biopsy (CNB) is variable on open excision. The purpose of the present study was to develop and validate a simple-to-use nomogram for predicting the upgrade of ADH diagnosed with ultrasound (US)-guided core needle biopsy in patients with US-detected breast lesions.

Methods

Two retrospective sets, the training set (n = 401) and the validation set (n = 186), from Fudan University Shanghai Cancer Center between January 2014 and December 2019 were retrospectively analyzed. Clinicopathological and US features were selected using univariate and multivariable logistic regression, and the significant features were incorporated to build a nomogram model. Model discrimination and calibration were assessed in the training set and validation set.

Results

Of the 587 ADH biopsies, 67.7% (training set: 267/401, 66.6%; validation set: 128/186, 68.8%) were upgraded to cancers. In the multivariable analysis, the risk factors were age [odds ratio (OR) 2.739, 95% confidence interval (CI): 1.525–5.672], mass palpation (OR 3.008, 95% CI: 1.624–5.672), calcifications on US (OR 4.752, 95% CI: 2.569–9.276), ADH extent (OR 3.150, 95% CI: 1.951–5.155), and suspected malignancy (OR 4.162, CI: 2.289–7.980). The model showed good discrimination, with an area under curve (AUC) of 0.783 (95% CI: 0.736–0.831), and good calibration (p = 0.543). The application of the nomogram in the validation set still had good discrimination (AUC = 0.753, 95% CI: 0.666–0.841) and calibration (p = 0.565). Instead of surgical excision of all ADHs, if those categorized with the model to be at low risk for upgrade were surveillanced and the remainder were excised, then 63.7% (37/58) of surgeries of benign lesions could have been avoided and 78.1% (100/128) malignant lesions could be treated in time.

Conclusions

This study developed a simple-to-use nomogram by incorporating clinicopathological and US features with the overarching goal of predicting the probability of upgrade in women with ADH. The nomogram could be expected to decrease unnecessary surgery by nearly two-third and to identify most of the malignant lesions, helping guide clinical decision making with regard to surveillance versus surgical excision of ADH lesions.

Development and Prospective Validation of a Risk Calculator That Predicts a Low Risk Cohort for Atypical Ductal Hyperplasia Upstaging to Malignancy: Evidence for a Watch and Wait Strategy of a High-Risk Lesion

BACKGROUND

Guidelines recommend surgical excision of atypical ductal hyperplasia (ADH) due to the concern of undersampling a potential malignancy on core needle biopsy (CNB). The purpose of this study was to determine clinical, radiological and pathological variables associated with ADH upstaging to cancer and to develop a predictive risk calculator capable of identifying women who have a low oncological risk of upstaging.

METHODS

A prospectively collected database from a tertiary breast referral center was analyzed for women diagnosed with ADH on CNB between January 2013 to December 2017 who underwent surgical excision. CNB and surgical pathology reports were examined to determine rate of upstaging. The association between clinical, radiological and pathological variables were evaluated using regression analysis to determine predictors of ADH upstaging to cancer. Significant variables (p ≤ 0.05) identified on univariate analysis were assigned a score of "1" and were included in the ADH upstaging risk calculator.

RESULTS

A total of 1986 patients underwent surgery for a high-risk lesion. We identified 318 (16.0%) patients who had ADH identified on their CNB who underwent surgery-of which 290 were included in our study. The upstage rate was 24.8%. Five variables were associated with upstaging and included in our calculator: (1) lesion > 5 mm on ultrasound; (2) lesion > 5 mm on mammogram; (3) one or more "high-risk" lesion(s) on CNB; (4) pathological suspicion for cancer and; (5) incomplete removal of calcifications on CNB. Patients with a score of 0 had a 2% risk of being upstaged to cancer and were deemed low risk with 17.2% of patients falling within this category.

CONCLUSIONS

Patients with ADH on CNB can be stratified into a low oncological cohort who have a 2% risk of being upstaged to carcinoma. In the future, these select patients may be counselled and potentially offered observation as an alternative to surgery.

Atypical Ductal Hyperplasia and Those Bordering on Ductal Carcinoma In Situ Should Be Included in the Active Surveillance Clinical Trials

OBJECTIVES

Women with atypical ductal hyperplasia (ADH), unlike those with ductal carcinoma in situ (DCIS), are denied eligibility for active surveillance clinical trials.

METHODS

We applied the inclusion criteria of the Comparison of Operative to Monitoring and Endocrine Therapy (COMET) trial to the cases of women (n = 165) at the Roswell Park Cancer Institute who had a diagnosis of ADH, ADH bordering on DCIS, or low- to intermediate-grade DCIS on core biopsy taken during screening mammography. Upgrade of lesions to high risk was based on invasive carcinoma, high-grade DCIS, or DCIS with comedo necrosis.

RESULTS

In total, nine (5.5%) lesions were upgraded: two (1.7%) reported ADH, one (5.9%) reported ADH bordering on DCIS, and six (19.4%) reported DCIS (P = .002); and two (1.6%) reclassified ADH vs seven (17.1%) reclassified DCIS (P < .001). In multivariate analysis, only increased number of foci had the potential to predict high risk (odds ratio: 1.39; P = .06).

CONCLUSIONS

We conclude that ADH and ADH bordering on DCIS have lower upgrade rates than DCIS. We recommend opening an active surveillance clinical trial for women with these diagnoses.