Abstract P3-15-03: Imaging and invasive lobular carcinoma: A survey study conducted by the lobular breast cancer alliance

Abstract

Abstract Background: The Lobular Breast Cancer Alliance (LBCA) is an advocacy organization guided by an expert advisory board. Since it launched in 2017, LBCA has been committed to raising awareness of the distinct aspects of invasive lobular carcinoma (ILC) and promoting ILC research. While ILC is the second most common histological breast cancer type representing 15% of breast cancer diagnoses in the United States annually, it is understudied compared to the more common invasive ductal carcinoma (IDC). ILC tumor cell density and lack of desmoplastic stromal reaction can pose challenges to detection by physical examination and mammography. Many studies have shown decreased accuracy of breast imaging tools for ILC, and those with ILC are often diagnosed at later stages and require more extensive surgery. We sought to hear from members of the LBCA community with ILC about their experiences with detection of their tumors. Methods: LBCA conducted an anonymous survey online. A link to the survey on the SurveyMonkey platform was made available for two weeks in June. It was sent to LBCA newsletter subscribers and posted to the LBCA website and ILC social media groups. The survey questions included stage and size of tumors at initial diagnosis and after surgery, and questions related to imaging for advanced ILC. It specifically asked whether and what type of mammogram initially detected the ILC. Results: Within 24 hours over 1,000 people responded, and a total of 1,476 people previously diagnosed with ILC responded by survey close. The majority of participants, 1,052 (72%), were from the US, followed by participants from 35 additional countries. 170 (12%) reported having metastatic ILC. 1,035 (70%) of respondents were under 60 at diagnosis. Of respondents reporting tumor size and stage, 936 (67%) of respondents indicated having a tumor larger than 2cm at diagnosis, and 897 (63%) reported stage 2 or higher, including 73 (5%) reporting stage 4 at initial diagnosis. In the subset of participants initially diagnosed with stage 2 or higher, 410 (46%) of respondents reported the tumor was not detected by mammogram. In the subset of participants who noticed changes in their breasts prior to the diagnosis, 521 (79%) had tumors larger than 2cm, and 490 (74%) were diagnosed at stage 2 or higher. Of the 1,241 respondents who had no preoperative therapy, 531 (43%) had tumors larger than initially seen on imaging and/or 321 (26%) had more tumors than initially found on imaging. Discussion: To the best of our knowledge this represents the largest survey seeking to understand patients’ experience with imaging to diagnose or visualize ILC. The results from this community survey of patients diagnosed with invasive lobular carcinoma confirmed patients’ perceptions of mammography as an imperfect screening tool to detect ILC. Of note were the findings that mammography failed to visualize 46% of ILC cases at stage 2 or higher, and the majority of respondents had tumors diagnosed/detected at stage 2 or higher and at sizes greater than 2cm. Moreover, participants often reported that the actual tumor size on the final pathology specimen was larger than seen on diagnostic imaging, and a significant number of respondents were diagnosed de novo metastatic. In summary, our findings affirm patients’ perception about the limitations of diagnostic and monitoring imaging of ILC. Our impressively large response also demonstrates the urgent need from patients’ perspectives for more research on better methods for detecting and monitoring ILC to improve outcomes for patients diagnosed with lobular disease. Citation Format: Laurie B Hutcheson, Janice Axelrod, Colleen L Fitzwater, Maxine S Jochelson, Gitte H Joergensen, Theresa Langdon, Julia K Levine, Otto Metzger, Mason Mitchell-Daniels, Barbara F Neilsen. Imaging and invasive lobular carcinoma: A survey study conducted by the lobular breast cancer alliance [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-15-03.