Abstract P3-03-21: Biological and Cultural Drivers of Early-Onset Breast Cancer: a mixed-method study
Authors: Houghton Lauren , Ulanday Kathleene T. , Topaz Maxim , Walker Desiree , Lewis Stacy , Terry Mary Beth 
Published: March 2023

Abstract
Background: The incidence of early-onset breast cancer (BC) in adults &lt; 40 years old has increased dramatically in the US over recent decades. The increase in incidence means that identifying higher risk individuals through family-history based guidelines will miss many young adults. As no population-based screening is recommended for adults under 40, so how they detect their BC remains unclear. Using data from a nested case-control study in the Breast Cancer Family Registry, we found that the steroid metabolome may improve risk assessment. If replicated in larger studies, it will be important to know more about the clinical contexts in which this biomarker screening could be implemented from both the provider and patient perspectives. One way to fill these gaps is to identify biocultural drivers of risk that deepen our etiologic understanding and inform risk assessment. We use quantitative and qualitative (mixed) methods to integrate “emics”—the on the ground perspective—from young adults with BC into metabolomic studies. Methods: For the provider perspective, we administered a survey to Obstetricians/gynecologists (OBGYNs) about their knowledge of American College of Obstetrics and Gynecology (ACOG) breast cancer screening guidelines for women under 40 and determined the proportion of correct responses. For the patient perspective, we examined qualitative data from the Young Survival Coalition (YSC). The YSC hosts an online forum where young adults with breast cancer “tell their story” in posts. We reviewed text from posts published between March 2009 and December 2019 and coded text (n=750 posts) according to themes: “first signs and symptoms,” “steps to diagnosis,” “staging type,” and “patient-provider feelings.” Then, we used natural language processing and machine learning with the support vector machine algorithm to build classification models and detect the themes in all posts (n=571,602). We repeated this process for sub-themes. Results: ACOG guidelines recommend that women at “average risk” of breast cancer are counseled about breast self-awareness, and 75% of OBGYN respondents answered this survey question correctly. Our qualitative, “emic” data suggest that the vast majority of young adults find their BC through self-awareness and first seek care from OBGYNs. They first noticed signs (n=3,266) of breast changes through self-detection of lumps (56.5%), self-detected breast and health changes (25.0%), and through a provider (17.2%). The first steps to diagnosis (n=31,640) mainly started with clinic visits (66.5%), others with surgery (23.3%). Stage at diagnoses (n=71,879) were Stage 4 (7.3%), followed by Stage 0 (7.2%), Stage 2-3 (5.5%), and Stage 1 (4.8%), while others mentioned being diagnosed with any invasive cancer (7.3%). Out of 24,648 posts, 70.3% were not satisfied with their providers and felt ignored, their treatment delayed, lacked trust, and felt their providers were not informed. One person said, “My doctor has not had a patient as young as me get diagnosed with cancer and has not suggested ANYONE.” Conclusions: In addition to counseling about breast self-awareness as a means of detection, the OBGYN setting may be a place to implement biomarker-based screening for early-onset BC. These results are derived from our mixed-methods approach, designed to identify biocultural drivers of cancer prevention by incorporating “omics” and “emics”. In the era of “omics,” when molecular markers are incorporated into cancer risk reduction and early detection, “emics” are equally important to identify what is feasible in “real-world” settings.
Citation Format: Lauren Houghton, Kathleene T. Ulanday, Maxim Topaz, Desiree Walker, Stacy Lewis, Mary Beth Terry. Biological and Cultural Drivers of Early-Onset Breast Cancer: a mixed-method study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-03-21.