Serial Postoperative Circulating Tumor DNA Assessment Has Strong Prognostic Value During Long-Term Follow-Up in Patients With Breast Cancer.

PURPOSE: Here, we report the sensitivity of a personalized, tumor-informed circulating tumor DNA (ctDNA) assay (Signatera) for detection of molecular relapse during long-term follow-up of patients with breast cancer. METHODS: A total of 156 patients with primary breast cancer were monitored clinically for up to 12 years after surgery and adjuvant chemotherapy. Semiannual blood samples were prospectively collected, and analyzed retrospectively to detect residual disease by ultradeep sequencing using ctDNA assays, developed from primary tumor whole-exome sequencing data. RESULTS: Personalized Signatera assays detected ctDNA ahead of clinical or radiologic relapse in 30 of the 34 patients who relapsed (patient-level sensitivity of 88.2%). Relapse was predicted with a lead interval of up to 38 months (median, 10.5 months; range, 0-38 months), and ctDNA positivity was associated with shorter relapse-free survival (P < .0001) and overall survival (P < .0001). All relapsing triple-negative patients (n = 7/23) had a ctDNA-positive test within a median of 8 months (range, 0-19 months), while the 16 nonrelapsed patients with triple-negative breast cancer remained ctDNA-negative during a median follow-up of 58 months (range, 8-99 months). The four patients who had negative tests before relapse all had hormone receptor-positive (HR+) disease and conversely, five of the 122 nonrelapsed patients (all HR+) had an occasional positive test. CONCLUSION: Serial postoperative ctDNA assessment has strong prognostic value, provides a potential window for earlier therapeutic intervention, and may enable more effective monitoring than current clinical tests such as cancer antigen 15-3. Our study provides evidence that those with serially negative ctDNA tests have superior clinical outcomes, providing reassurance to patients with breast cancer. For select cases with HR+ disease, decisions about treatment management might require serial monitoring despite the ctDNA-positive result.

Dying To Find Out: The Cost of Time at the Dawn of the Multicancer Early Detection Era.

Cancer is a significant burden worldwide that adversely impacts life expectancy, quality of life, health care costs, and workforce productivity. Although currently recommended screening tests for individual cancers reduce mortality, they detect only a minority of all cancers and sacrifice specificity for high sensitivity, resulting in a high cumulative rate of false positives. Blood-based multicancer early detection tests (MCED) based on next-generation sequencing (NGS) and other technologies hold promise for broadening the number of cancer types detected in screened populations and hope for reducing cancer mortality. The promise of this new technology to improve cancer detection rates and make screening more efficient at the population level demands the development of novel trial designs that accelerate clinical adoption. Carefully designed clinical trials are needed to address these issues.

Preclinical safety assessment of MV-s-NAP, a novel oncolytic measles virus strain armed with an H . pylori immunostimulatory bacterial transgene.

Despite recent therapeutic advances, metastatic breast cancer (MBC) remains incurable. Engineered measles virus (MV) constructs based on the attenuated MV Edmonston vaccine platform have demonstrated significant oncolytic activity against solid tumors. The Helicobacter pylori neutrophil-activating protein (NAP) is responsible for the robust inflammatory reaction in gastroduodenal mucosa during bacterial infection. NAP attracts and activates immune cells at the site of infection, inducing expression of pro-inflammatory mediators. We engineered an MV strain to express the secretory form of NAP (MV-s-NAP) and showed that it exhibits anti-tumor and immunostimulatory activity in human breast cancer xenograft models. In this study, we utilized a measles-infection-permissive mouse model (transgenic IFNAR KO-CD46Ge) to evaluate the biodistribution and safety of MV-s-NAP. The primary objective was to identify potential toxic side effects and confirm the safety of the proposed clinical doses of MV-s-NAP prior to a phase I clinical trial of intratumoral administration of MV-s-NAP in patients with MBC. Both subcutaneous delivery (corresponding to the clinical trial intratumoral administration route) and intravenous (worst case scenario) delivery of MV-s-NAP were well tolerated: no significant clinical, laboratory or histologic toxicity was observed. This outcome supports the safety of MV-s-NAP for oncolytic virotherapy of MBC. The first-in-human clinical trial of MV-s-NAP in patients with MBC (ClinicalTrials.gov: NCT04521764) was subsequently activated.

Feasibility of Longitudinal ctDNA Assessment in Patients with Uterine and Extra-Uterine Leiomyosarcoma.

Background: Leiomyosarcomas (LMS) are aggressive malignancies with a propensity for early relapse. Current surveillance modalities include physical exam and imaging; however, radiological response to therapy may only manifest after 4-6 cycles of treatment. Herein, we evaluated the feasibility of longitudinal circulating tumor DNA (ctDNA) assessment in LMS patients to identify disease progression. Methods: We performed a retrospective review of patients with LMS who underwent treatment at Stanford Cancer Center between September 2019 and May 2022. ctDNA detection was performed using a personalized, tumor-informed ctDNA assay. Genomic analysis was conducted to characterize tumor mutation burden (TMB) and known driver mutations. Results: A total of 148 plasma samples were obtained from 34 patients with uterine (N = 21) and extrauterine (N = 13) LMS (median follow-up: 67.2 (19-346.3) weeks] and analyzed for ctDNA presence. Nineteen patients had metastatic disease. The most frequently mutated driver genes across sub-cohorts were TP53, RB1, and PTEN. Patients were stratified into four sub-cohorts (A-D) based on ctDNA kinetics. ctDNA levels tracked longitudinally with progression of disease and response to therapy. Conclusion: Our results indicate that while undetectable ctDNA may suggest a lower likelihood of relapse, ctDNA positivity may indicate progressive disease, enabling closer monitoring of patients for early clinical intervention.

Assessment of Residual Cancer Burden and Event-Free Survival in Neoadjuvant Treatment for High-risk Breast Cancer: An Analysis of Data From the I-SPY2 Randomized Clinical Trial.

IMPORTANCE: Residual cancer burden (RCB) distributions may improve the interpretation of efficacy in neoadjuvant breast cancer trials. OBJECTIVE: To compare RCB distributions between randomized control and investigational treatments within subtypes of breast cancer and explore the relationship with survival. DESIGN, SETTING, AND PARTICIPANTS: The I-SPY2 is a multicenter, platform adaptive, randomized clinical trial in the US that compares, by subtype, investigational agents in combination with chemotherapy vs chemotherapy alone in adult women with stage 2/3 breast cancer at high risk of early recurrence. Investigational treatments graduated in a prespecified subtype if there was 85% or greater predicted probability of higher rate of pathologic complete response (pCR) in a confirmatory, 300-patient, 1:1 randomized, neoadjuvant trial in that subtype. Evaluation of a secondary end point was reported from the 10 investigational agents tested in the I-SPY2 trial from March 200 through 2016, and analyzed as of September 9, 2020. The analysis plan included modeling of RCB within subtypes defined by hormone receptor (HR) and ERBB2 status and compared control treatments with investigational treatments that graduated and those that did not graduate. INTERVENTIONS: Neoadjuvant paclitaxel plus/minus 1 of several investigational agents for 12 weeks, then 12 weeks of cyclophosphamide/doxorubicin chemotherapy followed by surgery. MAIN OUTCOMES AND MEASURES: Residual cancer burden (pathological measure of residual disease) and event-free survival (EFS). RESULTS: A total of 938 women (mean [SD] age, 49 [11] years; 66 [7%] Asian, 103 [11%] Black, and 750 [80%] White individuals) from the first 10 investigational agents were included, with a median follow-up of 52 months (IQR, 29 months). Event-free survival worsened significantly per unit of RCB in every subtype of breast cancer (HR-positive/ERBB2-negative: hazard ratio [HZR], 1.75; 95% CI, 1.45-2.16; HR-positive/ERBB2-positive: HZR, 1.55; 95% CI, 1.18-2.05; HR-negative/ERBB2-positive: HZR, 2.39; 95% CI, 1.64-3.49; HR-negative/ERBB2-negative: HZR, 1.99; 95% CI, 1.71-2.31). Prognostic information from RCB was similar from treatments that graduated (HZR, 2.00; 95% CI, 1.57-2.55; 254 [27%]), did not graduate (HZR, 1.87; 95% CI, 1.61-2.17; 486 [52%]), or were control (HZR, 1.79; 95% CI, 1.42-2.26; 198 [21%]). Investigational treatments significantly lowered RCB in HR-negative/ERBB2-negative (graduated and nongraduated treatments) and ERBB2-positive subtypes (graduated treatments), with improved EFS (HZR, 0.61; 95% CI, 0.41-0.93) in the exploratory analysis. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, the prognostic significance of RCB was consistent regardless of subtype and treatment. Effective neoadjuvant treatments shifted the distribution of RCB in addition to increasing pCR rate and appeared to improve EFS. Using a standardized quantitative method to measure response advances the interpretation of efficacy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01042379.

The PATHFINDER Study: Assessment of the Implementation of an Investigational Multi-Cancer Early Detection Test into Clinical Practice.

To examine the extent of the evaluation required to achieve diagnostic resolution and the test performance characteristics of a targeted methylation cell-free DNA (cfDNA)-based multi-cancer early detection (MCED) test, ~6200 participants ≥50 years with (cohort A) or without (cohort B) ≥1 of 3 additional specific cancer risk factors will be enrolled in PATHFINDER (NCT04241796), a prospective, longitudinal, interventional, multi-center study. Plasma cfDNA from blood samples will be analyzed to detect abnormally methylated DNA associated with cancer (i.e., cancer "signal") and a cancer signal origin (i.e., tissue of origin). Participants with a "signal detected" will undergo further diagnostic evaluation per guiding physician discretion; those with a "signal not detected" will be advised to continue guideline-recommended screening. The primary objective will be to assess the number and types of subsequent diagnostic tests needed for diagnostic resolution. Based on microsimulations (using estimates of cancer incidence and dwell times) of the typical risk profiles of anticipated participants, the median (95% CI) number of participants with a "signal detected" result is expected to be 106 (87-128). Subsequent diagnostic evaluation is expected to detect 52 (39-67) cancers. The positive predictive value of the MCED test is expected to be 49% (39-58%). PATHFINDER will evaluate the integration of a cfDNA-based MCED test into existing clinical cancer diagnostic pathways. The study design of PATHFINDER is described here.

TBCRC009: A Multicenter Phase II Clinical Trial of Platinum Monotherapy With Biomarker Assessment in Metastatic Triple-Negative Breast Cancer.

PURPOSE: The identification of patients with metastatic triple-negative breast cancer (mTNBC) who are expected to benefit from platinum-based chemotherapy is of interest. We conducted a single-arm phase II clinical trial of single-agent platinum for mTNBC with biomarker correlates. PATIENTS AND METHODS: Patients with mTNBC received first- or second-line cisplatin (75 mg/m(2)) or carboplatin (area under the concentration-time curve 6) by physician's choice once every 3 weeks. Coprimary end points were objective response rate (RR) and response prediction by p63/p73 gene expression. Secondary and exploratory end points included toxicity assessment, RR in cisplatin versus carboplatin, and RR in molecularly defined subgroups, including BRCA1/2 mutation carriers. RESULTS: Patients (N = 86; 69 as first-line therapy) received cisplatin (n = 43) or carboplatin (n = 43). RR was 25.6% (95% CI, 16.8% to 36%) and was numerically higher with cisplatin (32.6%) than with carboplatin (18.7%). RR was 54.5% in patients with germline BRCA1/2 mutations (n = 11). In patients without BRCA1/2 mutations (n = 66), exploratory analyses showed that a BRCA-like genomic instability signature (n = 32) discriminated responding and nonresponding tumors (mean homologous recombination deficiency-loss of heterozygosity/homologous recombination deficiency-large-scale state transitions [HRD-LOH/HRD-LST] scores were 12.68 and 5.11, respectively), whereas predefined analysis by p63/p73 expression status (n = 61), p53 and PIK3CA mutation status (n = 53), or PAM50 gene expression subtype (n = 55) did not. Five of the six long-term responders alive at a median of 4.5 years lacked germline BRCA1/2 mutations, and two of them had increased tumor HRD-LOH/HRD-LST scores. CONCLUSION: Platinum agents are active in mTNBC, especially in patients with germline BRCA1/2 mutations. A measure of tumor DNA repair function may identify patients without mutations who could benefit from platinum therapy agents. Prospective controlled confirmatory trials are warranted.