Abstract P5-22-07: Upgrade to high risk lesions, in situ and invasive cancer among women with benign papillary lesions diagnosed on image-guided core needle biopsy (IGCNB)
Authors: Kuehner G , Darbinian JA , Butler S , Chang S , Fehrenbacher L , Chen R , Habel LA , Axelsson K 
Published: February 2018

Abstract
Background: Currently there is no consensus regarding the management of benign papillary breast lesions diagnosed on IGCNB. Recommendations vary as to whether all IGCNB papillary lesions require surgical excision or if IGCNB alone is adequate to confirm a benign diagnosis and patients can be followed with imaging.
Aims: To estimate percentage of patients with benign papilloma on IGNB who on surgical excision are upgraded to high risk lesion, in situ or invasive cancer and to identify patient, imaging, and/or pathologic features that are predictive of upgrade.
Methods: We conducted a study of 407 patients within Kaiser Permanente Northern California (KPNC) diagnosed with benign papillary breast lesions on IGCNB in 2012 and 2013. KPNC is a large integrated health care delivery system, racially and ethnically diverse, and representative of the underlying population. Patients were excluded from study if they were &lt; 18 years, had atypia on IGCNB, had a prior history of breast cancer or high risk lesion, had a hereditary risk for developing breast cancer, or were noted to have papillomatosis or an incidental papilloma, or the target lesion was calcifications. Patients who did not have surgical excision of the IGCNB papilloma were followed for at least 2 years. Outcomes included in situ/invasive cancer and high risk lesions (atypical ductal or lobular hyperplasia, lobular carcinoma in-situ or papilloma with atypia). Outcomes were evaluated by review of medical records, including radiology, pathology, and surgical reports. The KPNC cancer registry and record review was used to exclude patients with a history of cancer.
Results: Among patients with benign papillary lesions, the average age was 56.4 years (range 20-93). Approximately 60% of lesions were 1 cm or less and 50% were centrally located (within 2 cm of nipple). There were 327 patients (80%) with surgical excision within 10 months of IGCNB, 61 patients (15%) with no surgical excision but follow-up imaging, and 19 patients (5%) with no surgery or follow-up imaging. Patients with and without surgical excision generally had similar age, breast density, and lesion location. However, surgical excision was more common among women with larger lesions. Among women with surgical excision, 9.5% (95% CI 6.3-12.7%) had a high risk lesion, 3.4% (95% CI 1.4-5.3-%) had an in situ lesion and 2.4% (95% CI 0.8-4.1%) had invasive cancer (all node negative). Less than 3% of women under 50 years, presenting with nipple discharge or with lesions less than 1 cm had invasive cancer on surgical excision. In contrast, over 10% of women with lesions greater than 1 cm, a palpable mass, or with lesions 5 or more cm from the nipple had invasive cancer on surgical excision. There were no cancers diagnosed among the 61 women followed by imaging; although 1 woman was upgraded to a high risk lesion.
Conclusions: In this large cohort of patients with benign papillary lesions on IGCNB, less than 3% had an invasive cancer on surgical excision. Upgrade was most common among patients with larger lesions, a palpable mass or lesions distant from the nipple and least common among women less than 50 years, with small lesions or presenting with nipple discharge.
Citation Format: Kuehner G, Darbinian JA, Butler S, Chang S, Fehrenbacher L, Chen R, Habel LA, Axelsson K. Upgrade to high risk lesions, in situ and invasive cancer among women with benign papillary lesions diagnosed on image-guided core needle biopsy (IGCNB) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-07.