Chumsri, Saranya

Abstract Background: We previously demonstrated that intrinsic subtypes were associated with prognosis for early recurrence risk in patients (pts) with early-stage HER2-positive (HER2+) BC treated with trastuzumab (H) in the N9831 trial. Here, we evaluated the prognostic value of Intrinsic subtypes and 21-gene assay and the risk of early and late recurrence in the N9831 trial. Methods: NanoString custom code set, which included PAM50 and housekeeping genes, was used to quantify mRNA and generated intrinsic subtypes and risk of recurrence (ROR) score from the N9831 trial in Arms A and C: Arm A chemotherapy alone and arm C concurrent H. Quantitative RT-PCR of 21 genes, calculation of the axis, including estrogen axis (ER, PGR, BCL2, SCUBE2), HER2 axis (GRB7, HER2), proliferation axis (Ki67, STK15, Survivin, CCNB1, MYBL2), invasion axis (MMP11, CTSL2), and recurrence score (RS) risk group assignment (RS group 1 and 2: RS < 31 and RS group 3: RS ≥ 31) were performed using Oncotype DX assay. Cox regression models for RFS were used for analysis. Early recurrence was defined as a recurrence that occurred at ≤ 5 years, and late recurrence was defined as recurrence at > 5 years. Results: A total of 783 patients (Arm A 409 and Arm C 374) were included in this analysis. Using multivariate Cox regression analysis to evaluate the risk of early recurrence in patients who received chemotherapy alone in arm A, both invasion genes (MMP11 HR 1.23, 95%CI 1.05-1.44, p 0.01 and CTSL2 HR 1.36, 95%CI 1.1-1.69, p 0.005) and invasion axis (HR 1.64, 95%CI 1.26-2.13, p < 0.001) were associated with a higher rate of early recurrence. CD68 was associated with improved outcomes (HR 0.56, 95%CI 0.38-0.83, p 0.004). For the risk of early recurrence in patients treated with trastuzumab in arm C, ER (HR 0.85, 95%CI 0.74-0.97, p 0.02), PR (HR 0.78, 95%CI 0.64-0.94, p 0.008), and estrogen axis (HR 0.7, 95%CI 0.57-0.87, p 0.001) were associated with improved outcomes. Invasion axis (HR 1.61, 95%CI 1.08-2.41, p 0.02), Oncotype Dx risk group (3 vs. 1 and 2, HR 8.89, 95%CI 1.27-1124, p 0.02), and basal subtype (HR 2.77, 95%CI 1.1-5.95, p 0.03) were also significantly associated with worse outcomes. For risk of late recurrence, in arm A, ER (HR 1.22, 95%CI 1.04-1.44, p 0.02), PR (1.26, 95%CI 1.05-1.5, p 0.01), and estrogen axis (1.39, 95%CI 1.09-1.77, p 0.008) were associated with worse outcomes. Oncotype Dx risk group (3 vs. 1 and 2, HR 0.4, 95%CI 0.16-0.98, p 0.05) was associated with improved outcomes. However, neither individual gene, axis, nor intrinsic subtypes were associated with the risk of late recurrence in patients treated with trastuzumab. Conclusions: For risks of early recurrence, the invasion genes/axis were associated with increased risks of recurrence in patients with early-stage HER2+ BC regardless of trastuzumab treatment. Among patients treated with trastuzumab, ER genes/axis, Oncotype Dx risk group, and intrinsic subtype were prognostic for risks of recurrence in the first five years. For risks of late recurrence, ER genes/axis and Oncotype Dx risk group were prognostic but only in patients treated with chemotherapy alone. The ER genes/axis were associated with less recurrence in the first five years but worse after five years, reflecting a higher risk of late recurrence in ER/PR+ HER2+ BC patients treated with chemotherapy alone. However, none of the individual gene, axis, or intrinsic subtypes were associated with the risk of late recurrence in patients treated with trastuzumab. Therefore, future studies are needed to identify biomarkers for the risk of late recurrence in HER2+ BC patients treated with adjuvant trastuzumab. Support: BCRF-19-161; U10CA180821, U10CA180882, Genentech. https://acknowledgments.alliancefound.org; Clinicaltrials.gov Identifier: NCT00005970 Citation Format: Saranya Chumsri, Zhuo Li, Nadine Norton, Alvaro Moreno-Aspitia, Gerardo Colon-Otero, Keith L. Knutson, Antonio C. Wolff, Edith A. Perez, E. A. Thompson. Effects of Intrinsic Subtypes and 21-gene Assay on the Early and Late Recurrence Risks in Patients with Early Stage HER2+ Breast Cancer: An Analysis of the North Central Cancer Treatment Group (NCCTG) N9831 (Alliance) 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 P2-11-05.

While breast cancer is a common disease with many available treatment options, many patients still have limited responses, especially those with metastatic breast cancer. Surgery of the primary tumor or metastatic sites is often not part of the treatment regimen for patients with metastatic breast cancer. Cryoablation is a relatively non-invasive procedure that is being investigated for patients with breast cancer. Patients with metastatic breast cancer who are not surgical candidates may derive benefit from cryoablation through the abscopal effect. In this case report, we present a patient with stage IV breast cancer who was treated with cryoablation of the primary breast tumor and showed evidence of an abscopal effect in regional and distant metastases.

PURPOSE APOBEC mutagenesis underlies somatic evolution and accounts for tumor heterogeneity in several cancers, including breast cancer (BC). In this study, we evaluated the characteristics of a real-world cohort for time-to-treatment discontinuation (TTD) and overall survival on CDK4/6 inhibitors (CDK4/6i) plus endocrine therapy (ET) and immune checkpoint inhibitors. METHODS Comprehensive genomic profiling results from 29,833 BC samples were analyzed for tumor mutational burden and APOBEC signatures. For clinical outcomes, a deidentified nationwide (United States–based) BC Clinico-Genomic Database (CGDB) was evaluated with log-rank and Cox models. Patients with hormone receptor–positive (HR+) human epidermal growth factor receptor 2–negative (HER2–) BC who received first-line ET and CDK4/6i were included. Eligible patients from Mayo Clinic and Duke University were HR+ HER2– BC with sequencing data between September 2013 and July 2020. RESULTS Of 29,833 samples sequenced, 7.9% were APOBEC+ with a high rate in invasive lobular carcinoma (16.7%) and in metastatic tumors (9.7%) relative to locally biopsied BC (4.3%; P < .001). In CGDB, 857 patients with HR+ HER2– BC received ET plus CDK4/6i in the first line. APOBEC+ patients had significantly shorter TTD on ET plus CDK4/6i than APOBEC– patients, 7.8 (95% CI, 4.3 to 14.6) versus 12.4 months (95% CI, 11.2 to 14.1; hazard ratio, 1.6; 95% CI, 1.03 to 2.39; P = .0036). Clinical benefit to immune checkpoint inhibitors was observed in HR+ HER2–, APOBEC+, tumor mutational burden–high patients, with four of nine CGDB patients (TTD 0.3-11.3 months) and four of six patients in Duke/Mayo cohorts (TTD 0.9-40.5 months) with a TTD of ≥ 3 months. CONCLUSION APOBEC+ HR+ HER2– patients had shorter TTD on first-line ET plus CDK4/6i relative to APOBEC– patients. Further research is needed to optimize the treatment of APOBEC+ HR+ HER2– BC and to investigate the efficacy of immunotherapeutic strategies in this population.

Abstract Background Some patients with inflammatory bowel disease (IBD) on immunosuppressive therapies may have a blunted response to certain vaccines, including the messenger RNA (mRNA) coronavirus disease 2019 (COVID-19) vaccines. However, few studies have evaluated the cell-mediated immune response (CMIR), which is critical to host defense after COVID-19 infection. The aim of this study was to evaluate the humoral immune response and CMIR after mRNA COVID-19 vaccination in patients with IBD. Methods This prospective study (HERCULES [HumoRal and CellULar initial and Sustained immunogenicity in patients with IBD] study) evaluated humoral immune response and CMIR after completion of 2 doses of mRNA COVID-19 vaccines in 158 IBD patients and 20 healthy control (HC) subjects. The primary outcome was the CMIR to mRNA COVID-19 vaccines in patients with IBD. The secondary outcomes were a comparison of (1) the CMIR in patients with IBD and HC subjects, (2) CMIR and humoral immune response in all participants, and (3) correlation between CMIR and humoral immune response. Results The majority (89%) of patients with IBD developed a CMIR, which was not different vs HC subjects (94%) (P = .6667). There was no significant difference (P = .5488) in CMIR between immunocompetent (median 255 [interquartile range, 146-958] spike T cells per million peripheral blood mononuclear cells) and immunosuppressed patients (median 377 [interquartile range, 123-1440]). There was no correlation between humoral and cell-mediated immunity after vaccination (P = .5215). In univariable analysis, anti-tumor necrosis factor therapy was associated with a higher CMIRs (P = .02) and confirmed in a multivariable model (P = .02). No other variables were associated with CMIR. Conclusions Most patients with IBD achieved CMIR to a COVID-19 vaccine. Future studies are needed evaluating sustained CMIR and clinical outcomes.

The usage of beta blockers in breast cancer (BC) patients is implicated in the reduction in distant metastases, cancer recurrence, and cancer mortality. Studies suggest that the adrenergic pathway is directly involved in sympathetic-driven hematopoietic activation of pro-tumor microenvironmental proliferation and tumor cell trafficking into the circulation. Cancer-associated macrophage-like cells (CAMLs) are pro-tumor polynucleated monocytic cells of hematopoietic origin emanating from tumors which may aid in circulating tumor cell (CTC) dissemination into the circulation. We examined the linkage between Beta-2 adrenergic receptor (B2AR) signaling in CAMLs and CTCs by establishing expression profiles in a model BC cell line (MDA-MB-231). We compared the model to CAMLs and CTCs found in patents. Although internalization events were observed in patients, differences were found in the expression of B2AR between the tumor cell lines and the CAMLs found in patients. High B2AR expression on patients’ CAMLs was correlated with significantly more CAMLs in the circulation (p = 0.0093), but CTCs had no numerical relationship (p = 0.1565). High B2AR CAML expression was also significantly associated with a larger size of CAMLs (p = 0.0073), as well as being significantly associated with shorter progression-free survival (p = 0.0097) and overall survival (p = 0.0265). These data suggest that B2AR expression on CAMLs is closely related to the activation, intravasation, and growth of CAMLs in the circulation.

BNCT is a high LET radiation therapy modality that allows for biologically targeted radiation delivery to tumors while reducing normal tissue impacts. Although the clinical use of BNCT has largely been limited to phase I/II trials and has primarily focused on difficult-to-treat malignancies such as recurrent head and neck cancer and recurrent gliomas, recently there has been a renewed interest in expanding the use of BNCT to other disease sites, including breast cancer. Given its high LET characteristics, its biologically targeted and tumor specific nature, as well as its potential for use in complex treatment settings including reirradiation and widespread metastatic disease, BNCT offers several unique advantages over traditional external beam radiation therapy. The two main boron compounds investigated to date in BNCT clinical trials are BSH and BPA. Of these, BPA in particular shows promise in breast cancer given that is taken up by the LAT-1 amino acid transporter that is highly overexpressed in breast cancer cells. As the efficacy of BNCT is directly dependent on the extent of boron accumulation in tumors, extensive preclinical efforts to develop novel boron delivery agents have been undertaken in recent years. Preclinical studies have shown promise in antibody linked boron compounds targeting ER/HER2 receptors, boron encapsulating liposomes, and nanoparticle-based boron delivery systems. This review aims to summarize the physical and biological basis of BNCT, the preclinical and limited clinical data available to date, and discuss its potential to be utilized for the successful treatment of various breast cancer disease states.

Abstract Background: Previous studies showed conflicting results regarding association between stromal tumor infiltrating lymphocytes (sTIL) and outcome in HER2+ breast cancer. While sTIL were not associated with outcome in patients (pts) treated with trastuzumab in N9831, immune functions genes are linked to outcome in these pts. TLS is an organized form of ectopic lymphoid aggregates (LA) with secondary lymphoid organ structure. Several studies showed that TLS associates with improved outcome in multiple cancers. However, distinguishing TLS and simple LA is challenging, particularly when germinal center is absent. In this study, we evaluated integrated pathological quantification and genomic data to assess functional TLS. Methods: Pathological evaluation of LA in H&E slides from pts treated in Arm A (chemotherapy alone) and Arm C (chemotherapy with concurrent trastuzumab) in N9831 was performed. NanoString was used to quantify mRNA. Wilcoxon rank sum test, Chi squared test, Kaplan-Meier method and Cox regression model were used to evaluate association between LA and baseline characteristics as well as outcomes. Results: LA was quantified in 1011 pts (526 Arm A, 485 Arm C). Greater number of LA was significantly associated with higher tumor grade, ER/PR negativity and increasing sTIL, but not age, tumor size or lymph node status. Increasing numbers of LA were associated with improved RFS in both arms combined (p 0.028). However, using multivariable Cox regression analysis in each treatment arm, LA (≥ 1 vs 0) was associated with improved RFS only in Arm A (HR 0.6, 95%CI 0.43-0.84, p 0.003) but not Arm C (HR 0.72, 95%CI 0.47-1.1, p 0.134). Further evaluation of expression of TLS-related immune genes including IFNG, ICOSLG, CXCL13, CXCR3, BCL6, IL21R, ICOS, PDCD1, CXCR5, CXCL9, TBX21, CD38, CXCL10, CLXCL11, IL21, CD200 was carried out among 252 pts in Arm C with LA ≥ 1. Among these 16 TLS-related immune genes, as a continuous variable, higher expression of BCL6 (HR 0.61, 95%CI 0.41-0.92, p 0.019) and IL21R (HR 0.78, 95%CI 0.62-0.98, p 0.03) were associated with improved RFS in Arm C pts with LA ≥ 1. However, these genes were not significantly associated with outcome in Arm C pts without LA with BCL6 HR1.07 (95%CI 0.67-1.71, p 0.776) and IL21R HR 0.96 (95%CI 0.71-1.29, p 0.775). Conclusion: Similar to sTIL, greater number of LA was associated with improved outcome in HER2+ pts treated with chemotherapy alone but not chemotherapy in combination with trastuzumab. Using histogenomic integration with the combination of pathological LA and TLS-related immune genes, we identified that pts with functional TLS with LA ≥ 1 and higher expression of BCL6 or IL21R had significantly improved outcome when treated with trastuzumab. Future studies are needed to further confirm these findings. Support: U10 CA180821, U24 CA196171, https://acknowledgments.alliancefound.org; Genentech; Clinicaltrials.gov Id: NCT00005970 Citation Format: Saranya Chumsri, Tracy R. Shachner, Zhuo Li, Nadine Norton, Alvaro Moreno-Aspitia, Gerardo Colon-Otero, Edith A. Perez, E. A. Thompson, Aziza Nassar, Keith L. Knutson. Functional tertiary lymphoid structure (TLS) and outcome in HER2-positive (HER2+) breast cancer in NCCTG N9831 (Alliance) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5627.

3056 Background: In metastatic Breast Cancer (mBC), Circulating Tumor Cells (CTCs) are established prognostic indicators of patients (pts) not responding to new lines of therapy and who have poor clinical outcomes. However, CTCs are typically found in < 20% of mBC pts and many pts without CTCs will also progress. Recently an inflammatory pro-tumorigenic macrophage emanating from tumor stroma (i.e. Cancer associated macrophage-like cell [CAML]) was found in > 90% of mBC pts and were also indicative of poor clinical outcomes. As CTCs & CAMLs are isolated in conjunction from a single blood sample, and both are prognostic for therapy response, we evaluated CTCs & CAMLs before and after initiation of new therapies in mBC to determine their combined prognostic/predictive values. Methods: An observational prospective 2-year multi-institutional study was undertaken to evaluate CTCs & CAMLs before, and after, induction of any new line of therapy in pts with diagnosed mBC (n = 101). Anonymized and blinded blood samples were taken at baseline (BL), prior to starting a new systemic therapy, and a 2nd sample (T1) taken after therapy initiation (̃30 days). Blood was filtered by CellSieve filtration. The quantities and subtypes of CTCs & CAMLs were analyzed based on RECIST v1.1 for progression-free survival (PFS) and overall survival (OS) hazard ratios (HRs) by censored univariate & multivariate analysis at 2 years. Results: CTCs were identified in 35% (n = 35/101) of pts at BL & 24% (n = 24/101) at T1, with a single CTC at T1 being highly prognostic for worse PFS HR = 6.2 95%CI 3.0-13.2, p < 0.001 & OS (HR = 5.1 95%CI 2.0-13.4, p = 0.002. In parallel, CAMLs were found in 93% of BL and 86% of T1 samples, and whose decreases were significantly prognostic for improved PFS (HR = 2.7, 95%CI 1.4-5.1, p = 0.006) and OS (HR = 4.4 95%CI 1.5-13.2, p = 0.018) when CTCs were absent. Overall ≥1 CTC at T1 (n = 24) had median PFS = 2.4 & mOS = 4.8 months (mos), however, in pts without CTCs plus an increase in CAMLs (n = 36) had mPFS = 5.9 & mOS = 14.1 mos, while in pts without CTCs plus a decrease in CAMLs (n = 41) had mPFS = 14.8 & mOS = 18.8 mos. Conclusions: Our data confirms that pts with persistent CTCs have the worst clinical outcomes. Further, simultaneous CAML quantification provided a new dynamic predictive blood based biomarker in pts without detectable CTCs which may be useful to better individualize therapy and improve outcomes, though future studies are need to validate these findings.

TPS610 Background: Several studies demonstrated worsening disease-free survival in patients who failed to achieve complete pathological response after neoadjuvant chemotherapy (NAC), particularly in HER2-positive (HER2+) breast cancer. Despite the recent approval of trastuzumab emtansine (T-DM1) in patients with residual disease after NAC approximately 12% of patients still develop recurrent and metastatic disease. TPIV100 is a multi-epitope vaccine that includes a pool of 4 degenerate HER2-derived HLA-DR epitopes, which activate CD4 helper T cells, admixed with GM-CSF. In our previous phase I trial this vaccine was shown to be safe in combination with trastuzumab in stage II-III HER2+ breast cancer after completion of standard of care chemotherapy. Furthermore, this vaccine also generated robust long-lasting T-cell immune responses and antibody immunity against HER2. Methods: This trial is a multi-center, randomized, placebo-controlled, phase II trial of TPIV100 in combination with T-DM1 in stage II-III HER2+ breast cancer patients with residual disease after NAC. This trial is currently opened through the ACCRU consortium. Eligible patients include those with stage II-III HER2+ with residual disease, in the breast and/or lymph nodes, after trastuzumab ± pertuzumab-based NAC, with ECOG PS ≤ 2 and adequate organ function. Patients with baseline left ventricular ejection fraction < 50%, history of trastuzumab-related cardiac toxicity, myocardial infarction or stroke < 6 months, history of congestive heart failure, autoimmune disease, immunocompromised patients with known HIV or those on chronic steroid, hypersensitivity to GM-CSF, and other active malignancy < 3 years are excluded. TPIV100 or placebo, in combination with GM-CSF, will be given concurrently with T-DM1. To ensure that TPIV100 in combination with T-DM1 is safe, there is a run-in phase with 20 patients treated with the combination. If there is no significant dose-limiting toxicity observed in the run-in phase, the trial will be expanded to the randomized phase II portion, which will include 240 patients. Eligible patients will be randomized in a 2:1 fashion with ER/PR as a stratification factor. The primary endpoint is invasive disease-free survival, and the secondary endpoint includes immunogenicity of TPIV100 as assessed by IFN-g ELIspot analysis. Correlative studies include assessment of helper T-cell response distribution (including Th1, Th2, Th17, Tfh), HER2-specific antibody immunity, and HLA genotype. Currently, 20 patients in the run-in phase have been enrolled. Enrollment to the randomized phase II portion is expected to begin in March 2022. Clinical trial information: NCT04197687.

522 Background: Our preclinical findings suggest a role for the mevalonate pathway (MVA) in treatment resistance in HER2+ BC by providing alternative growth and survival signaling to bypass potent HER2 blockade, which could be overcome by the MVA inhibitors statins and nitrogen-containing bisphosphonates (NBs). Here we explored the effect of MVA inhibitors’ use on pts’ outcomes in the ALTTO trial (BIG2-06; NCT00490139). Methods: In the ALTTO trial, 8381 pts with HER2+ BC were randomized to 1 year of adjuvant lapatinib (L), trastuzumab (T), L+T, or T→L. All pts with documented treatment start with statins or NBs < 1 year after randomization were considered as MVA inhibitors users. Survival curves, with a median follow-up of 6.9 years, for disease-free survival (DFS), distant relapse-free interval (DRFI), BC-specific survival (BCSS), and overall survival (OS) according to MVA inhibitors use were estimated by the Kaplan Meier method and Log-rank test. All multivariate survival analyses employed a Cox proportional hazards regression model, adjusting for tumor size, nodal status, hormonal receptor (HoR), menopausal status, BMI, timing of chemo, and randomization arm. We considered interactions terms in Cox’s model between MVA inhibitors use and randomization arm, hormonal status, and BMI group. Results: Among the 8381 pts included in this study, 493 and 299 were statins or NBs users, respectively. Table 1 summarizes the significant differences in pts’ characteristics according to MVA inhibitors use ( P <.005). In multivariate survival analyses, only NBs use was associated independently with better BCSS (HR, 0.44; 95% CI, 0.23 - 0.84; P = 0.014). Statin use was not independently associated with prognosis but only in interaction with pts characteristics: worse DFS, BCSS and OS in pts treated with L+T, worse DRFI and OS in pts treated with HoR+ BC (respective interaction P-values <0.05 in the Cox’s model). Conclusions: NBs independently predicted improved BC-specific outcome in pts with HER2+ BC treated with adjuvant anti-HER2 therapy. Statin use was associated with an inferior outcome in pts with HoR+ disease and/or those treated with L+T. Whether this inferior association in statin users may reflect the underlying predisposition factors that can weaken the efficacy of anti-HER2 treatments and whether this effect was observed only in the L+T arm due to the more potent inhibition of the HER2 signaling pathway remain open questions. Further clinical investigations on the impact of MVA inhibitors on the outcome of pts with HER2+ BC are warranted. [Table: see text]