Asymptomatic Benign Papilloma Without Atypia Diagnosed at Ultrasonography-Guided 14-Gauge Core Needle Biopsy: Which Subgroup can be Managed by Observation?

Background: For asymptomatic benign papillomas detected at ultrasonography-guided 14-gauge core-needle biopsy (US–CNB), the decision to perform excision versus observation has been a topic of debate. We sought to determine which subgroup of asymptomatic benign papillomas without atypia diagnosed at US–CNB can be safely managed by observation versus immediate excision. Materials: Overall, 230 asymptomatic benign papillomas in 197 women (mean age 46.6 ± 9.5 years; range 22–78), diagnosed at US–CNB using immunohistochemistry staining when needed and then managed by surgery (n = 144) or vacuum-assisted excision (VAE) with at least 12 months of follow-up after benign VAE results (n = 86) were included in this study. The upgrade rate to malignancy was calculated. Clinical and radiological variables, including age, size, Breast Image Reporting and Data System (BI–RADS) category, and imaging–pathology correlation were evaluated to find associations with malignancy using multivariate analysis. Results: The upgrade rate to malignancy was 2.6 % (6 of 230): four were ductal carcinomas in situ and two were 1.5- and 9-mm-sized invasive ductal carcinomas without lymph node metastasis. The upgrade rates of papillomas with a BI–RADS category 3–4a and imaging–pathology concordance were 1.4 and 1.8 %, respectively. Category 4b–5 and imaging–pathology discordance were independently associated with malignancy, with upgrade rates of 13 and 50 %, respectively. Age and lesion size were not associated with malignancy. Conclusion: Asymptomatic benign papillomas with probable benign or low suspicious US features or imaging–pathology concordance can be followed-up as opposed to immediate excision.