Abstract PS7-57: Patient risk factors for loss to breast oncologic follow up
Authors: Chudasama Rani , Olszewski Adam , Dizon Don , Fenton Mary Anne 
Published: February 2021

Abstract
For patients who complete treatment for breast cancer, national oncologic guidelines recommend yearly mammography surveillance and oncology follow-up especially during the first five years of survivorship. Some studies have shown that older age and insurance type may be risk factors for timely initial follow up after abnormal mammogram however the role in which racial and socioeconomic disparities may contribute to long term non-adherence or loss to follow-up (LTFU) is not known. Investigation into causes of LTFU or non-receipt of recommended surveillance are crucial in improving health care delivery and targeting interventions that prevent LTFU in high-risk patients. An ongoing study at Lifespan Breast Oncology aims to evaluate this issue further among patients treated for stage 1-3 breast cancer. We have completed data collection on 139 of 300 eligible patients diagnosed in 2014 and for whom 5 years of follow up have been completed. We measured adherence to yearly mammography, visit with breast oncologist, continuation of ET, and LTFU in each year of survivorship. LTFU was defined as patient without any further contact with the Lifespan Breast Oncology clinic. We then examined the association between these adherence measures and age, ECOG performance status at diagnosis, Medicaid insurance status, socio-economic factors, and specific adjuvant therapies, using univariate and multivariate generalized estimating equation models for longitudinal data. The models reported odds ratios (OR) for non-adherence or LTFU, with 95% confidence intervals (CI). Patients who experienced relapse or death were removed from the pool in the year of event. Adherence decreased for all measures between year 1 and year 5 of survivorship: from 99% to 82% for oncology visits, 92% to 80% for mammography, and 86% to 71% from ET. LTFU increased from 0% to 17%, respectively (OR per year, 1.96; 95%CI, 1.55-2.48). In univariate analysis, patients age &gt;70 (compared with age ≤50) had a significantly higher risk of LTFU (Table), non-adherence to visits (OR=6.64 versus age ≤50, P=.002), mammography (OR=4.18, P=.020), or ET (OR=5.42, P=.002). Patients with performance status ECOG ≥2 had significantly lower adherence to all measures. Medicaid insurance was associated with significantly higher LTFU, non-adherence to mammography (OR=5.58, P=.008) or oncology visits (OR=6.53, P=.002). Marital, employment, or parenting status were not significantly associated with the risk of LTFU, but employed patients had a higher adherence to mammography and ET. Cancer stage, ER, or HER2 status were not associated with any adherence measure. LTFU was lower among recipients of ET, but not recipients of chemotherapy. In a multivariable model, Medicaid insurance (OR=3.99, P=.027) and receipt of ET (OR=0.32, P=.027) retained significant association with LTFU. Our findings show that Medicaid patients represent a high risk group with potential need for increased resources to ensure adequate follow-up. We plan to continue to expand this cohort and analyze more patients at our institution. Interventions to change barriers and circumvent financial limitations that these patients face in obtaining care could potentially decrease rates of recurrence and potentially impact overall survival. This data could be utilized in future studies to create a risk stratification tool to identify patients who would be at high risk for LTFU.
Table. Factors associated with loss to follow-up.N (%)% LTFU at 5yOR95%CIPAll13917Age ≤5032 (23)161.00351-7070 (50.4)120.890.27-2.90&gt;7037 (26.6)223.511.19-10.4ECOG 015 (10.8)71.0071108 (77.7)153.650.43-31.1&gt; 214 (10.1)2920.281.90-216Insurance: private78 (56.1)91.001Medicaid15 (10.8)466.762.03-22.5Medicare45 (32.4)195.131.98-13.3Children: no70 (50.4)121.34yes66 (47.5)191.710.56-5.22Married: no56 (40.3)171.68yes83 (59.7)160.840.38-1.88Employed: no70 (50.4)201.32yes66 (47.5)150.660.29-1.49Stage:187 (62.6)181.66239 (28.1)120.640.24-1.69313 (9.4)220.80.19-3.46ER-23 (16.5)261.27ER+115 (82.7)150.580.22-1.54No ET38 (27.3)291.033ET101 (72.7)120.410.18-0.93No chemotherapy87 (62.6)171.25Chemotherapy52 (37.4)160.60.25-1.43
Citation Format: Rani Chudasama, Adam Olszewski, Don Dizon, Mary Anne Fenton. Patient risk factors for loss to breast oncologic follow up [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-57.