Background: The management of benign intraductal papillomas on core biopsy is controversial. The aim of this study was to determine factors that predict under-evaluation of atypical lesion or malignancy in patients diagnosed with benign papilloma at ultrasound-guided core needle biopsy (CNB), and to develop a prediction algorithm for scoring the possibility of a diagnosis upgrade to atypical lesion or malignancy based on clinical, radiological and pathological factors.

Methods: The study enrolled patients diagnosed with benign papilloma at ultrasound-guided CNB who subsequently underwent surgical excision of the lesion. Multivariate analysis was used to identify relevant clinical, radiological and pathological factors that may predict malignancy.

Results: A total of 520 CNBs led to a diagnosis of benign papilloma (including benign and atypical papillary lesion), of which 452 CNBs were benign papilloma without atypia. Of the 250 lesions in 234 women were underwent subsequent surgical excision, 44 (17.6%) were diagnosed with atypia or malignancy. Multivariate analysis revealed that bloody nipple discharge, size on imaging ≥15 mm, BIRADS≥4b, peripheral location, and a palpable lesion were independent predictors of atypical lesion or malignancy. A scoring system was developed based on logistic regression models and beta coefficients for each variable. The area under the ROC curve was 0.830 (95% CI: 0.665-0.996), and the negative predictive value was 100% for a score ≤4.

Conclusions: A scoring system to predict malignancy in patients diagnosed with benign papilloma at CNB was developed based on five factors: bloody nipple discharge, size on imaging ≥15 mm, BIRADS≥4b, peripheral location, and a palpable lesion. This system was able to identify a subset of patients with lesions likely to be benign, indicating that imaging follow-up rather than surgical excision may be appropriate.

Citation Format: Ahn Sk, Moon H-G, Han W, Noh D-Y, Ko E. To excise or not?: Scoring system for predicting malignancy in patients diagnosed with intraductal papilloma at ultrasound-guided core needle biopsy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-03-04.