Haddad, Tufia C.

Introduction: patients exposed to chest, breast or mediastinal RT, may present with accelerated atherosclerosis and CAD due to diffuse micro and macrovascular fibrosis. However, CAD risk has not been well established in a community-based study. Aims: Describe CAD risk in patients treated with chemotherapy with and without RT and evaluate the cumulative incidence of CAD (coronary revascularization, MI and abnormal stress test and coronary angiogram). Methods: From 1985-2010, we identified 744 patients with a new diagnosis of breast cancer or lymphoma, using the Rochester Epidemiology Project (REP) who received chemotherapy with or without RT. CAD risk was assessed by a proportional hazards model for time to event. RT was treated as a time dependent co-variable, with index date being chemotherapy start date, significance was considered as a p<.05. Characteristics were evaluated by a multivariable Cox model to consider RT and time censoring. Results: 744 patients treated with chemotherapy were identified, of these 488 (65.6%) had breast cancer, 256 (34.4%) lymphoma, and 367 (49%) also received RT. The mean total RT dose was 5.5 ± 1.2 (Gy) for those that had CAD and 5.4 (Gy) ± 1.1 for non-CAD patients, p=0.4. The cumulative incidence of CAD events (accounting for death as a competing risk) at 5 and 10 years of follow-up was 1.9% (CI 1.14-3.2) and 3.06% (CI 2.01-4.7), respectively p<.05 figure1. Baseline differences between those receiving RT or not, were not significant for DM and HTN; however, males and ages 70-79 were less likely to receive RT, table1. In a multivariable model, there was no difference in the CAD outcomes between those with and without RT, HR= 1.21 [0.48-3.06] p=.69, after adjusting for age, gender, DM, and HTN and those <49 y/o had a lower risk of CAD. Table2 Conclusion: In this REP retrospective cohort study, the risk of developing a CAD event was similar between chemotherapy plus RT and chemotherapy only regimens, even after considering gender, age, HTN and DM.

1535 Background: Ambulatory management of select patients with febrile neutropenia (FN) may substantially decrease patients’ burden of illness and improve their quality of life, and is recommended by American Society of Clinical Oncology (ASCO) guidelines. However, in the United States, inpatient management remains the universal standard. We hereby report the health care utilization associated with the DEFeNDR remote patient monitoring (RPM) program, which leverages technology and virtual centralized nurse monitoring to facilitate ambulatory management of FN as an alternative to hospital-based care. Methods: Adult patients with cancer hospitalized with FN were assessed daily for eligibility to participate in the DEFeNDR program. Eligibility criteria included MASCC score >21 (per ASCO guidelines), and clinical judgment of the attending provider. Patients receiving cellular therapy (CAR-T, BMT) in the prior 100 days were excluded. Eligible patients agreeing to participate in the 30-day program were provided a kit containing cellular-enabled, pre-connected devices to facilitate monitoring, including twice-daily vital signs and electronic symptom questionnaires. Data were EHR-integrated in real-time and embedded decision trees facilitated alerts for adverse trends. RPM nurses responded to alerts and escalated care as indicated by pre-specified care pathways. Program assessment was performed at 20 weeks after full implementation. The primary outcome was the mean proportion of evaluable days spent inpatient (mPEDI) within 30 days of eligibility compared between those who participated in the program vs. those who declined. Results: 35 patients were offered participation in the DEFeNDR program. Of these, 17 participated and 18 declined. Baseline characteristics are provided. Participating patients experienced mPEDI of 6.9% (Standard Error [SE], 3.7%), compared with 17.7% (SE, 3.6%) for patients who declined participation. Due to small sample size, this difference (10.8%) did not reach statistical significance (Wilcoxon Rank Sums p-value, 0.15). 30-day mortality did not differ between groups. Mean inpatient days were also lower for patients participating in the program. Additionally, when readmitted, patients participating in RPM experienced a trend toward shorter length of stay and lower rates of intensive care unit utilization. Conclusions: A trend towards decreased burden of inpatient care is evident among patients participating in the DEFeNDR program. Further studies are warranted to assess comparative effectiveness of this model vs usual care.[Table: see text]

e13100 Background: Aurora-A mitotic kinase (AURKA) plays a pivotal role in Triple Negative Breast Cancer (TNBC) progression through activation of epithelial to mesenchymal transition (EMT)-mediated cancer cell plasticity. Cancer cells that undergo EMT acquire a CD44high/CD24low and/or ALDHhigh cancer stem-like phenotype (Cancer Stem Cells) characterized by high self-renewal capacity and intrinsic drug resistance. Cancer Stem Cells (CSCs) also shows high PD-L1 expression that plays a critical role in inducing tumor immune escape through CD8+ T-cells exhaustion. For these reasons, molecular characterization of oncogenic pathways that promote stemness and intra-tumoral PD-L1 expression is essential to evaluate whether novel combinatorial therapeutic strategies aimed to inhibit cancer cell plasticity, immune evasion capacity and organ metastasis may impact cancer progression. Methods: (1) TNBC Models: MDA-MB 231 and variant MDA-MB 231/LM cells, and unique TNBC-M40 cells established from metastatic PDXs; (2) In Vitro Studies: TNBC cells were treated with the AURKA inhibitor alisertib (50nM). PD-L1 expression was evaluated by immunoblotting assay. Apoptosis was measured by immunofluorescence using Cleaved-PARP antibodies. To assess stemness capacity, TNBC cells were cultured under non-adherent conditions to form mammospheres. ALDH activity (functional stemness marker) was measured using the Aldefluor Kit. (3) In Vivo Studies: 1x106 MDA-MB 231/LM cells were injected into the mammary fat pad of humanized NSG-CD34+ female mice. Animals were randomized into four groups (5 mice per group) and treated with anti-PD-L1 ICI atezolizumab (20 mg/Kg) and alisertib (25 mg/Kg) as monotherapy or in combination. Control groups were treated with saline solution placebo. PD-L1, CD44, Vimentin expression and tumor infiltration of CD8+ T-cells were assessed by immunofluorescence. Results: Treatment of MDA-MB 231/LM xenografts with alisertib decreased the levels of CD44 and PD-L1 expression and increased CD8+ T-cells tumor infiltration. Because PD-L1 genetic targeting enhanced in vitro alisertib-induced apoptosis, MDA-MB 231/LM xenografts were treated with alisertib and the anti-PD-L1 ICI atezolizumab. Combination of atezolizumab and alisertib resulted in the reduced expression of the EMT marker vimentin that was linked to lack of organ metastasis. Remarkably, combination of atezolizumab and alisertib also induced a significant reduction of ALDHHigh CSC in ex-vivo 3D-Organoids established from TNBC-M40 cells. Conclusions: This study provides innovative pre-clinical rationale for combining AURKA inhibitors with ICIs to impair cancer cell plasticity, immune evasion capacity and halt the progression of metastatic TNBCs that currently has limited effective therapeutic options.

Abstract Purpose: Triple-negative invasive lobular carcinoma (TN-ILC) of breast cancer is a rare disease and the clinical outcomes and prognostic factors are not well-defined. Methods: Women with stage I-III TN-ILC or triple-negative invasive ductal carcinoma (TN-IDC) of the breast undergoing mastectomy or breast-conserving surgery between 2010 and 2018 in the National Cancer Database were included. Kaplan-Meier curves and multivariate Cox proportional hazard regression were used to compare overall survival (OS) and evaluate prognostic factors. Multivariate logistic regression was performed to analyze the factors associated with pathological response to neoadjuvant chemotherapy. Results: The median age at diagnosis for women with TN-ILC was 67 years compared to 58 years in TN-IDC (p<0.001). There was no significant difference in the OS between TN-ILC and TN-IDC in multivariate analysis (HR 0.96, p=0.44). Black race and higher TNM stage were associated with worse OS, whereas receipt of chemotherapy or radiation was associated with better OS in TN-ILC. Among women with TN-ILC receiving neoadjuvant chemotherapy, the 5-year OS was 77.3% in women with a complete pathological response (pCR) compared to 39.8% in women without any response. The odds of achieving pCR following neoadjuvant chemotherapy were significantly lower in women with TN-ILC compared to TN-IDC (OR 0.53, p<0.001). Conclusion: Women with TN-ILC are older at diagnosis but have similar OS compared to TN-IDC after adjusting for tumor and demographic characteristics. Administration of chemotherapy was associated with improved OS in TN-ILC, but women with TN-ILC were less likely to achieve complete response to neoadjuvant therapy compared to TN-IDC.

ImportanceAurora A kinase (AURKA) activation, related in part to AURKA amplification and variants, is associated with downregulation of estrogen receptor (ER) α expression, endocrine resistance, and implicated in cyclin-dependent kinase 4/6 inhibitor (CDK 4/6i) resistance. Alisertib, a selective AURKA inhibitor, upregulates ERα and restores endocrine sensitivity in preclinical metastatic breast cancer (MBC) models. The safety and preliminary efficacy of alisertib was demonstrated in early-phase trials; however, its activity in CDK 4/6i–resistant MBC is unknown.ObjectiveTo assess the effect of adding fulvestrant to alisertib on objective tumor response rates (ORRs) in endocrine-resistant MBC.Design, Setting, and ParticipantsThis phase 2 randomized clinical trial was conducted through the Translational Breast Cancer Research Consortium, which enrolled participants from July 2017 to November 2019. Postmenopausal women with endocrine-resistant, ERBB2 (formerly HER2)–negative MBC who were previously treated with fulvestrant were eligible. Stratification factors included prior treatment with CDK 4/6i, baseline metastatic tumor ERα level measurement (&amp;lt;10%, ≥10%), and primary or secondary endocrine resistance. Among 114 preregistered patients, 96 (84.2%) registered and 91 (79.8%) were evaluable for the primary end point. Data analysis began after January 10, 2022.InterventionsAlisertib, 50 mg, oral, daily on days 1 to 3, 8 to 10, and 15 to 17 of a 28-day cycle (arm 1) or alisertib same dose/schedule with standard-dose fulvestrant (arm 2).Main Outcomes and MeasuresImprovement in ORR in arm 2 of at least 20% greater than arm 1 when the expected ORR for arm 1 was 20%.ResultsAll 91 evaluable patients (mean [SD] age, 58.5 [11.3] years; 1 American Indian/Alaskan Native [1.1%], 2 Asian [2.2%], 6 Black/African American [6.6%], 5 Hispanic [5.5%], and 79 [86.8%] White individuals; arm 1, 46 [50.5%]; arm 2, 45 [49.5%]) had received prior treatment with CDK 4/6i. The ORR was 19.6%; (90% CI, 10.6%-31.7%) for arm 1 and 20.0% (90% CI, 10.9%-32.3%) for arm 2. In arm 1, the 24-week clinical benefit rate and median progression-free survival time were 41.3% (90% CI, 29.0%-54.5%) and 5.6 months (95% CI, 3.9-10.0), respectively, and in arm 2 they were 28.9% (90% CI, 18.0%-42.0%) and 5.4 months (95% CI, 3.9-7.8), respectively. The most common grade 3 or higher adverse events attributed to alisertib were neutropenia (41.8%) and anemia (13.2%). Reasons for discontinuing treatment were disease progression (arm 1, 38 [82.6%]; arm 2, 31 [68.9%]) and toxic effects or refusal (arm 1, 5 [10.9%]; arm 2, 12 [26.7%]).Conclusions and RelevanceThis randomized clinical trial found that adding fulvestrant to treatment with alisertib did not increase ORR or PFS; however, promising clinical activity was observed with alisertib monotherapy among patients with endocrine-resistant and CDK 4/6i–resistant MBC. The overall safety profile was tolerable.Trial RegistrationClinicalTrials.gov Identifier: NCT02860000

Abstract Background: Two poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPi) are currently FDA-approved for the treatment of HER2-negative metastatic breast cancer (MBC) in carriers of germline pathogenic variants (PVs) in BRCA1 or BRCA2 (BRCA1/2). This study explores the clinical outcomes of MBC patients treated with a PARPi. Methods: In this retrospective study, we included MBC patients treated with a PARPi between January 2017 and February 2022 at Mayo Clinic (Minnesota, Arizona, Florida, and Mayo Clinic Health Systems). We used the Kaplan Meier method to estimate the time-to-treatment-failure (TTF) and the log-rank test to compare different subsets. In addition, predictors of TTF were identified in a multivariate cox-proportional hazard regression model, including age at PARPi initiation, race, ethnicity, histology, estrogen receptor (ER), progesterone receptor (PR), and HER2 expression of the tumor, the number of prior therapies, type of PARPi, and PV carrier status (germline BRCA1/2 or PALB2 vs. somatic BRCA1/2 vs. other). Results: Sixty-five patients treated with PARPi (olaparib: 51; talazoparib: 14) were included in the final analysis. Fifty-five patients were carriers of germline PVs in BRCA1 (n=24, 37%), BRCA2 (n=27, 42%) or PALB2 (n=4, 6%), whereas ten patients (15%) had no germline PVs but the tumor had a somatic mutation in the homologous recombination-related (HRR) genes (7 in BRCA1/2, 2 in ATM, and 1 in CDKN2A and CDH1). At the data cutoff, 48 (74%) patients had discontinued PARPi due to progression or death. Fifteen (23%) patients required a dose reduction due to side effects. Occurrence of grade ≥ 3 side effects: anemia in 8, fatigue in 4, neutropenia in 2, and thrombocytopenia in 2 patients. Eight (15.7%) patients in the olaparib group and seven (50%) patients in the talazoparib group required a dose reduction for side effects. No patient on olaparib required drug discontinuation due to side effects, whereas two patients on talazoparib were switched to olaparib due to cytopenias and could tolerate olaparib. Median TTF in the overall population was 8 months (95% confidence interval [CI]: 6.4 – 9.6), and there was no difference (p=0.64) in TTF between the olaparib and talazoparib groups. Median TTF in the germline BRCA1, BRCA2, and PALB2 PV carriers were 7, 8, and 11 months, respectively (p=0.57). Among patients with somatic BRCA1/2 mutations, the median TTF was 4 months. Numerically, patients with HER2-positive tumors (n=8) had a shorter TTF compared to HER2-negative tumors (Median TTF: 4 vs. 8 months, p=0.098). No significant difference in TTF was observed by ER or PR status of the tumor, age at initiation of PARPi, the number of prior therapies, and prior use of platinum-based chemotherapy or CDK4/6 inhibitors. In multivariate analysis, HER2 positivity (hazard ratio [HR]: 8.0, 95% CI: 2.2 – 29.4, p=0.002), somatic BRCA1/2 mutations (HR: 7.6, 95% CI: 1.2 – 50.0, p=0.03) and somatic mutations in other HRR genes (HR: 19.1, 95% CI: 3.1 – 118.6, p=0.002) were associated with worse TTF. Conclusions: In the real world, PARPi were well-tolerated with promising time-to-treatment-failure (TTF) benefits comparable to data from clinical trials. Notably, relatively shorter TTF was observed in patients with somatic BRCA1/2 and other HRR gene mutations and HER2-positive MBC. These findings improve our understanding of the role of PARPi in MBC and will help to guide treatment decisions with PARPi in the clinical setting. Citation Format: Nusrat Jahan, Jodi Taraba, Karthik V. Giridhar, Roberto A. Leon-Ferre, Amye J. Tevaarwerk, Elizabeth Cathcart-Rake, Ciara C. O’Sullivan, Prema Peethambaram, Timothy J. Hobday, Kathryn Ruddy, Lida A. Mina, Pooja Advani, Felipe Batalini, Matthew P. Goetz, Tufia C. Haddad, Fergus J. Couch, Siddhartha Yadav. Clinical outcomes of metastatic breast cancer patients treated with poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPi): the Mayo Clinic experience [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 P4-01-22.

Abstract Introduction: We performed matched case-control studies utilizing cohorts of postmenopausal women with ER+ breast cancer receiving adjuvant aromatase inhibitors (AI) on MA.27 [anastrozole, exemestane] or PreFace [letrozole] to assess the association between estrogen suppression after 6 months of treatment and an early breast cancer (EBC) event within 5 years of AI initiation (Clin Cancer Res 2020;26:2986-98). We found a significant 3.0-fold increase in risk of an EBC event for those taking anastrozole with levels of estrone (E1) ≥1.3 pg/mL and estradiol (E2) ≥0.5 pg/mL, but not for exemestane or letrozole. Given these findings we designed a prospective pharmacodynamic (PD) study to evaluate the impact of anastrozole (1 mg/day: ANA1) on E1 and E2 levels, and among those with inadequate estrogen suppression (IES: E1 ≥1.3 pg/mL and E2 ≥0.5 pg/mL), to evaluate the safety and PD efficacy of high-dose anastrozole (10 mg/day: ANA10), which has been found to be safe in prior clinical trials (Cancer 1998;83:1142-52). Methods: Post-menopausal women with stage I-III, ER ≥1% positive/HER2-negative breast cancer who were candidates for anastrozole were eligible after completion of locoregional therapy and chemotherapy, as clinically indicated. Women who were pre-menopausal at diagnosis were not eligible. All patients received 8-10 weeks of ANA1, after which those with adequate estrogen suppression (AES: E1&lt; 1.3 pg/mL or E2&lt; 0.5 pg/mL) came off study. Those with IES went on to receive ANA10 for 8-10 weeks, followed by letrozole (2.5 mg/day: LET) for 8-10 weeks. All patients were managed at their treating oncologist’s discretion following study discontinuation. E1 and E2 blood levels were measured pre-treatment and after completion of each treatment cycle by a CLIA-approved liquid chromatography with tandem mass spectrometry in the Immunochemical Core Laboratory at Mayo Clinic. With a sample size of 29 patients with IES after ANA1, a one-sided binomial test of proportions with a significance level of 0.05 will have an 87% chance of rejecting the proportion with AES after ANA10 is at most 25% (Ho) when the true proportion is at least 50%. Specifically, the null hypothesis is rejected if the number of women with AES after ANA10 is 12 or more. Data lock was July 6, 2022. Results: Of the 161 women enrolled from April 2020 through May 2022, 3 withdrew consent prior to start of ANA1 and 2 were ineligible; thus, 156 women comprised the study cohort. Median patient age was 64 years (range 44-86), 10% of patients were of Hispanic ethnicity and/or non-white race, and 15% received chemotherapy. Six patients remain on ANA1, and 10 discontinued ANA1 due to refusal (7), adverse event (AE) (2), or COVID-19 (1). Forty-one of the remaining 140 patients (29.3%; 95%CI: 21.9-37.6%) had IES with ANA1. Nine of these 41 patients did not go on to ANA10 due to refusal (6) or AE (3). Of the 32 patients who started ANA10, 8 remain on treatment, 5 discontinued due to refusal (3) or AE (1-grade 2 urinary tract infection; 1-grade 1 palpitations), and 19 had a blood draw 45 days or more after starting ANA10. No grade 3-5 AEs or grade 2 hot flashes or arthralgias were reported. Of these 19 patients, 14 achieved AES with ANA10 (73.7%; 95%CI: 48.8-90.9%). All 19 patients switched to LET of which 3 remain on treatment, 1 is missing E1/E2 data, and 15 had a blood draw 45 days or more after starting LET. Of these 15 patients, 10 maintained AES, 2 acquired AES with LET, and 3 no longer had AES. Anastrozole and letrozole drug levels will be reported at the meeting. Conclusions: Approximately 29% of postmenopausal women with ER+/HER2- BC receiving adjuvant anastrozole 1 mg/daily had IES. A majority of these patients achieved AES with dose escalation to ANA10 without tolerability issues. E1 and E2 levels are logical biomarkers given the mechanism of action of anastrozole, and further study utilizing them to determine the optimal dose of anastrozole for a given patient should be performed. Citation Format: Tufia C. Haddad, Vera Suman, Karthik V. Giridhar, Alvaro Moreno-Aspitia, Donald Northfelt, Brenda Ernst, Kostandinos Sideras, Ciara C. O’Sullivan, Ravinder Singh, Zeruesenay Desta, Jodi Taraba, Barbara Goodnature, Matthew P. Goetz, Liewei Wang, James N. Ingle. Anastrozole dose escalation for optimal estrogen suppression in postmenopausal early stage breast cancer: A prospective trial [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 OT1-04-02.

ImportanceAnthracyclines increase the risk for congestive heart failure (CHF); however, long-term cumulative incidence and risk factors for CHF after anthracycline therapy are not well defined in population-based studies.ObjectiveTo compare the long-term cumulative incidence of CHF in patients with breast cancer or lymphoma treated with anthracycline therapy compared with healthy controls from the same community.Design, Setting, and ParticipantsThis retrospective population-based case-control study included data from the Rochester Epidemiology Project. Participants included residents of Olmsted County, Minnesota, diagnosed with breast cancer or lymphoma from January 1985 through December 2010 matched for age, sex, and comorbidities with healthy controls, with a final ratio of 1 case to 1.5 controls. Statistical analysis was performed between July 2017 and February 2022.ExposuresCancer treatment and CHF risk factors.Main Outcomes and MeasuresThe main outcome was new-onset CHF, as defined by the modified Framingham criteria. Cox proportional hazards regression was used to estimate hazard ratios (HRs) to compare the risk of CHF in participants with cancer vs controls, adjusted for age, sex, diabetes, hypertension, hyperlipidemia, coronary artery disease, obesity, and smoking history.ResultsA total of 2196 individuals were included, with 812 patients with cancer and 1384 participants without cancer. The mean (SD) age was 52.62 (14.56) years and 1704 participants (78%) were female. Median (IQR) follow-up was 8.6 (5.2-13.4) years in the case group vs 12.5 (8.7-17.5) years in the control group. Overall, patients with cancer had higher risk of CHF compared with the control cohort even after adjusting for age, sex, diabetes, hypertension, coronary artery disease, hyperlipidemia, obesity, and smoking status (HR, 2.86 [95% CI, 1.90-4.32]; P &amp;lt; .001). After adjusting for the same variables, CHF risk was greater for patients with cancer receiving anthracycline (HR, 3.25 [95% CI, 2.11-5.00]; P &amp;lt; .001) and was attenuated and lost statistical significance for patients with cancer not receiving anthracyclines (HR, 1.78 [95% CI, 0.83-3.81]; P = .14). Higher cumulative incidence for patients treated with anthracyclines vs comparator cohort was observed at 1 year (1.81% vs 0.09%), 5 years (2.91% vs 0.79%), 10 years (5.36% vs 1.74%), 15 years (7.42% vs 3.18%), and 20 years (10.75% vs 4.98%) (P &amp;lt; .001). There were no significant differences in risk of CHF for patients receiving anthracycline at a dose of less than 180 mg/m2 compared with those at a dose of 180 to 250 mg/m2 (HR, 0.54 [95% CI, 0.19-1.51]) or at a dose of more than 250 mg/m2 (HR, 1.23 [95% CI, 0.52-2.91]). At diagnosis, age was an independent risk factor associated with CHF (HR per 10 years, 2.77 [95% CI, 1.99-3.86]; P &amp;lt; .001).Conclusions and RelevanceIn this retrospective population-based case-control study, anthracyclines were associated with an increased risk of CHF early during follow-up, and the increased risk persisted over time. The cumulative incidence of CHF in patients with breast cancer or lymphoma treated with anthracyclines at 15 years was more than 2-fold that of the control group.

26 Background: We previously demonstrated that utilization of a Remote Patient Monitoring (RPM) program – characterized by the use of in-home technology for symptom and vital signs assessments with a centralized care team responding to alerts – is associated with a significant reduction in 30-day hospitalization rate among cancer patients with COVID-19. We have subsequently performed a 90-day comparative cost-of-care analysis in this prospectively enrolled, validated cohort of 71 patients who received RPM and 116 patients who received usual care without RPM. Methods: Primary outcomes included 90-day all-cause costs (categorized as hospital and outpatient costs) following the index date (date of COVID-19 diagnosis). Differences in patient characteristics and baseline costs (incurred 90 days prior to index date) were determined using Standardized Differences and controlled for using Inverse Probability Weighting (IPW). IPW balancing was based on baseline covariates known to be associated with poorer COVID-19 outcomes, as previously described. Association of costs with RPM was examined by generalized linear modeling while adjusting for relevant variables. Outcomes are reported as the average treatment effect on the treated (ATET). Results: Differences in patient characteristics and baseline costs were well-balanced following IPW modeling. The index ATET was found to be comparable among patients receiving RPM and usual care on the date of COVID-19 diagnosis -$89.75 (95% CI: -$144.33 to $323.84; p = 0.452). However, patients receiving RPM experienced a 90-day ATET of -$6,994 (95% CI: -$14,635 to $646; p = 0.073) when compared with patients receiving usual care. Conclusions: There was a trend towards decreased 90-day all-cause costs for cancer patients with COVID-19 who utilized the RPM program as compared with usual care. Larger studies are needed to understand the true cost (and cost savings) associated with this innovative model of care delivery which can be leveraged for cancer care beyond COVID-19.