Positive predictive value of ERBB2 copy number gain by tissue or circulating tumor DNA next-generation sequencing across advanced cancers

BACKGROUND

The correlation of ERBB2 copy number gain (CNG) from tissue or circulating tumor DNA (ctDNA) by next-generation sequencing (NGS) with standard HER2 tissue evaluation is not well understood.

MATERIALS AND METHODS

We retrospectively identified patients with ERBB2 CNG on commercial NGS. We described their clinical-pathologic features and calculated the positive predictive value (PPV) of ERBB2 CNG by NGS for HER2-positivity by IHC and FISH testing.

RESULTS

176 patients had NGS revealing an ERBB2 CNG (112 by tumor tissue and 91 by ctDNA). The cancer subtypes with the most cases with ERBB2 CNG by NGS were breast (n = 67), non-small cell lung (n = 25), colorectal (n = 18), gastroesophageal (n = 17), pancreatic (n = 11), and uterine (n = 11). The PPV of ERBB2 CNG in determining HER2 positivity by standard IHC/FISH definitions was 88% for tissue NGS (n = 57) and 80% for ctDNA (n = 47). The PPV among breast cancer patients for tissue NGS was 97% (n = 35) and ctDNA was 93% (n = 39). However, for non-breast cancer cases, the PPV of ERBB2 amplification by tissue NGS dropped to 76% (n = 22) and by ctDNA to 44% (n = 7).

CONCLUSIONS

ERBB2 CNG by NGS is detected in numerous malignancies for which HER2 testing is not standard. Detection of ERBB2 CNG by tissue NGS and ctDNA has a high PPV for true HER2-positivity by standard IHC and/or FISH testing in breast cancer.

A clinical prediction model to assess risk for pancreatic cancer among patients with prediabetes

BACKGROUND

Early detection of pancreatic ductal adenocarcinoma (PDA) may improve survival. We previously developed a clinical prediction model among patients with new-onset diabetes to help identify PDAs 6 months prior to the clinical diagnosis of the cancer. We developed and internally validated a new model to predict PDA risk among those newly diagnosed with impaired fasting glucose (IFG).

METHODS

We conducted a retrospective cohort study in The Health Improvement Network (THIN) (1995-2013) from the UK. Eligible study patients had newly diagnosed IFG during follow-up in THIN. The outcome was incident PDA diagnosed within 3 years of IFG diagnosis. Candidate predictors were factors associated with PDA, glucose metabolism or both.

RESULTS

Among the 138 232 eligible patients with initial IFG diagnosis, 245 (0.2%) were diagnosed with PDA within 3 years. The median time from IFG diagnosis to clinical PDA diagnosis was 326 days (IQR 120-588). The final prediction model included age, BMI, proton pump inhibitor use, total cholesterol, low-density lipoprotein, alanine aminotransferase and alkaline phosphatase. The model achieved good discrimination [area under the curve 0.71 (95% CI, 0.67-0.75)] and calibration (Hosmer and Lemeshow goodness-of-fit test P > 0.05 in 17 of the 20 imputed data sets) with optimism of 0.0012662 (95% CI, -0.00932 to 0.0108771).

CONCLUSIONS

We developed and internally validated a sequential PDA prediction model based on clinical information routinely available at the initial appearance of IFG. If externally validated, this model could significantly extend our ability to detect PDAs at an earlier stage.

HPV-mediated anal squamous cell carcinoma and precancerous lesions in HIV positive patients

3520

Background: Anal cancer affects over 8,000 patients per year in the United States and the incidence is increasing. A significant risk factor for anal cancer and precancerous lesions is human papilloma virus (HPV), with up to 90% of cases being associated with HPV infection. Another emerging risk factor is HIV co-infection. In the present study, we further address if CD4 count is a significant factor for driving higher-grade HPV-mediated anal squamous lesions in HIV/HPV co-infection patients with a single institution large cohort. Methods: A retrospective cohort of HPV-positive patients with anal biopsies was obtained from 2002-2020. Information on the grade of their anal lesion, HIV status, and CD4 count (cells/mm3) were collected. In patients with HIV, the most recent CD4 count up to one year prior to or one month after their biopsy was utilized in our analysis. Lesions were grouped into low grade squamous intraepithelial lesions (LSIL) and higher grade squamous intraepithelial lesions (HSIL), carcinoma in situ (CIS), or squamous cell carcinoma (SCC). The Center for Disease Control CD4 count levels to define HIV status were utilized in our sub-analyses. The distribution of lesion grades was compared between HIV-negative and -positive patients, and between HIV-negative and three subgroups of HIV-positive patients using the Fisher’s exact test. Results: Our cohort comprised of 3,354 total HPV-positive patients. 2,036 of these patients were HIV-negative and 1318 were HIV-positive. The proportion of higher grade lesions was significantly higher in HIV/HPV co-infected patients regardless of CD4 count (Table). The full cohort of HIV-positive patients had lower rates of LSIL (60.8% vs. 74.0%) and higher rates of higher-grade lesions (39.2% vs. 26.0%) (p<0.001) compared to HIV-negative patients. The distribution of lesion grades was also significantly different between HIV-negative patients and all HIV-positive patient subgroups, with all subgroups having higher rates of higher-grade lesions than HIV-negative patients (all p<0.001). Conclusions: Our data show that HIV-HPV co-infection is a risk factor for higher grade anal lesions, regardless of CD4 status. This suggests that CD4 count is not the only factor responsible for the increased risk of higher-grade anal lesions, as the groups of HIV-positive patients with CD4 counts between 200-499 and above 499 still had a higher rate of higher-grade lesions than HIV-negative patients. Further research into other HIV-related immunologic changes that increase risk for higher-grade HPV-driven anal lesions is warranted.[Table: see text]

Abstract PS2-26: Evaluating the pathogenicity of emerging genomic aberrations detected by circulating tumor DNA over the course of metastatic breast cancer

Introduction: Previously reported data from our group and others have demonstrated an increase in genomic complexity and number of alterations over the course of treatment in MBC. Our study aims to categorize the pathogenicity of genomic aberrations found on serial ctDNA evaluations in MBC to explore the relevance of emerging mutations. Methods: Patients with MBC and ctDNA next-generation sequencing (NGS) analysis by Guardant360 (Guardant Health, Redwood City, CA) completed from 2015 to 2019 were retrospectively identified with an IRB-approved protocol. Clinical-pathologic features and time point for progression of disease were abstracted from review of the electronic medical record. Among the 255 patients with ctDNA analysis, 85 patients had serial ctDNA analysis from baseline and at subsequent progression of disease (PD1) and 27 had repeat ctDNA analysis at next progression (PD2). Genomic alterations were classified as oncogenic, likely oncogenic, predictive oncogenic, likely benign, inconclusive, unknown significance, and synonymous based on categorization by OncoKB.org (Chakravarty et al, JCO PO 2017). Oncogenic, likely oncogenic, and predicted oncogenic were considered ‘pathogenic’ while the remainder were ‘not known pathogenic’. Two-sample t-tests for difference of means (α = 0.05) was used for analysis of changes in pathogenic proportions and mutant allele frequencies (MAF). Results: The median age was 53.8 years, 41 patients had hormone receptor positive (HR+) HER2-negative, 22 had HER2+, and 22 had triple negative (TN) MBC. The median and interquartile range (IQR) of the time of MBC diagnosis to first ctDNA collection was 10 mo (0.3-23.1 mo), from baseline ctDNA to analysis at the time of disease progression (PD1) was 6.7 mo (3.6-12.5 mo), and from PD1 to second progression (PD2) was 4.6 mo (3.1-8.5 mo). At baseline 66% of alterations were pathogenic (38.4% oncogenic, 27.6% likely oncogenic, 26.5% unknown significance). The proportion of pathogenic variants did not significantly change over time: 62% at PD1 (p=0.41) and 56% at PD2 (p=0.19). The percent of pathogenic alterations by disease subtype at baseline and PD1 was 66% and 60% in HR+ HER2-, 73% and 57% in HER2+, and 62% and 71% in TN. 57% and 70% of patients had a new pathogenic alteration at PD1 and PD2, respectively. The most frequently detected new pathogenic alterations at the time of disease progression were TP53, PIK3CA, ESR1, FGFR1, and MYC, which occurred in 28%, 18%, 15%, 12%, and 11% of patients, respectively. Among genes that were altered in at least 10% of patients, the aberrations were very likely to be pathogenic (&gt;75% of alterations pathogenic) for TP53, PIK3CA, ESR1, MYC, BRAF, FGFR1, often pathogenic (50-75% of alterations pathogenic) for NF1, KIT, GATA3, ERBB2, EGFR, CCNE1, PDGFRA, and often not known pathogenic (&lt;50% of alterations pathogenic) for MET, AR, ARID1A, and BRCA2. When comparing the mean MAF of pathogenic and not known pathogenic alterations, paired by gene, the MAF was not significantly different for pathogenic alterations except for GATA3 (p=0.03). Conclusion: The continued emergence of pathogenic mutations at times of progression without a corresponding increase in the proportion of pathogenic variants suggests that new pathogenic mutations may arise as a result of increased tumor genomic instability over time, although these findings require confirmation in larger datasets. The large proportion of patients who present with new pathogenic variants at disease progression supports the utility of ctDNA to track tumor evolution. Additionally, this study highlights the importance of considering the pathogenicity of genomic alterations, as over one-third of aberrations in MBC were not known to be pathogenic.

Citation Format: Ami N Shah, Andrew A Davis, Saya Jacob, Lorenzo Gerratana, Brian Finkelman, Shruti Chandra, Neelima Katam, Firas Wehbe, Jeeven Srivastava, Ashwin Sunderraj, Qiang Zhang, Leonidas Platanias, Amir Behdad, William Gradishar, Massimo Cristofanilli. Evaluating the pathogenicity of emerging genomic aberrations detected by circulating tumor DNA over the course of metastatic breast cancer [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 PS2-26.

Abstract PS7-74: Associations and spectrum of genetic mutations in younger patients with breast carcinoma and additional malignancies

Background: The development of cancer is understood to be a series of molecular events causing uncontrollable cell growth and malignant behavior. Primary breast carcinoma is associated with a number of molecular alterations that may also be implicated in the molecular deregulation underlying other malignancies. In addition, underlying germline genetic mutations have been clearly associated with the development of breast carcinoma (BC) in young patients. Increased risks for the development of additional malignancies following or preceding breast cancer have been reported, however, specific associations and genetic mutations remain unclear, especially in young patients.Materials and methods: Our patient cohort consisted of young women (&lt;!–=40 years of age) at our institution who were diagnosed with BC between May 2009 to May 2018. Retrospective review of electronic medical records was performed in order to identify the occurrence of a second neoplasm either before or after a BC diagnosis and germline genetic alterations were recorded.Results: 13 out of 437 young women were diagnosed with either a second malignancy or high-grade dysplasia. The clinico-pathologic characteristics of these patients are summarized in the Table 1. There was almost an equal distribution of these neoplasms occurring either before or after the diagnosis of BC. 6 tumors were diagnosed 10 months to 7 years after the diagnosis of BC, whereas 5 tumors diagnosed 1 month to 20 years earlier. Interestingly, only 2 cases were concurrently diagnosed and both of these were malignant phyllodes tumors of the breast.On studying the pathologic characteristics of the breast tumors in young patients with a second malignancy, the majority of these cancers were either grade 1 or grade 2 (10/13) while 3/13 were grade 3 carcinomas. Additionally, 10/13 of the cases were positive for estrogen receptor and negative for HER2, 2 cases were triple negative, and hormone receptor status was unknown in one case. 10/13 carcinomas were treated with mastectomy and the remaining 3 by lumpectomy. Lymph nodes were examined in 9 cases and one or more lymph nodes were found to be positive in 3 cases. Germline mutations panel (limited or complete) were available in 12 cases. Germline genetic alterations were found in three of the patients (3/12), as summarized in the Table 1. These included BRCA1 (2/12) and PTEN (1/12). Although variant of uncertain significance (VUS) mutations were also recognized in other genes e.g. ATM (1/12), SMAD4 (1/12) and MSH2 (1/12), those were not included in our analysis due to lack of current knowledge regarding their clinical significance.Additionally, 51 benign neoplasms were also diagnosed (e.g. benign nevi, thyroid adenomas, benign ovarian neoplasms, etc.). Nearly half (20/51) involved the female genital tract (uterus, cervix, or ovaries), 17 the skin and soft tissues, 4 the gastrointestinal tract, 8 the thyroid, and 1 the brain.Conclusions: Young women with BC are likely to have an underlying genetic predisposition for the development of BC and other malignancies. Although BRCA1 was the most common mutation observed, germline mutations of other genes were also seen. Therefore, genetic counselling, testing, and increased surveillance are extremely useful tools in managing the development of other associated malignancies in young women with BC.

Table 1: Summary of clinico-pathologic characteristics of BC with second malignanciesNo.Type of carcinomaGradePrognostic markersAssociated in-situ carcinomaAge at diagnosisSecondary diagnosisTimeline of second diagnosisInitial management of BCLymph node statusGenetic testing results1.Invasive lobular carcinoma1UnknownLobular carcinoma in situ39Malignant phyllodes tumorConcurrentMastectomyNegativeUnknown2.Invasive ductal carcinoma3Triple negativeDuctal carcinoma in situ36Squamous cell carcinoma, esophagus7 years laterMastectomyNegativeBRCA1+3.Invasive ductal carcinoma3Triple negativeNone38High grade serous carcinoma, ovary5 years laterMastectomyOne lymph node positiveBRCA1+4.Invasive ductal carcinoma with mucinous features1Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ33Gastrointestinal stromal tumor, jejunum7 years laterMastectomyNegativeNegative5.Invasive ductal carcinoma2Estrogen receptor+/Progesterone receptor+/HER2-Lobular carcinoma in situ31Malignant phyllodes tumor7 years earlierMastectomyNegativeNegative6.Invasive ductal carcinoma2Estrogen receptor+/Progesterone receptor-/HER2-Ductal carcinoma in situ37Complex endometrial hyperplasia with atypia and leiomyoma with Fumarate hydratase features6 years laterMastectomyNot performedNegative7.Invasive ductal carcinoma2Estrogen receptor+/Progesterone receptor+/HER2-None36Hodgkin disease20 years earlierMastectomyNegativeNegative8.Invasive ductal carcinoma3Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ29High grade squamous intraepithelial lesion1 year earlierMastectomyOne lymph node positiveNegative9.Invasive ductal carcinoma2Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ36High grade squamous intraepithelial lesion1.5 year laterMastectomyOne lymph node positiveNegative10.Invasive ductal carcinoma2Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ36High grade squamous intraepithelial lesion1 month earlierLumpectomyNegativeNegative11.Invasive ductal carcinoma1Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ38Endometrioid adenocarcinoma10 months laterLumpectomyNot performedCowden syndrome (PTEN gene)12.Invasive mucinous carcinoma1Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ41Papillary thyroid carcinoma14 years earlierLumpectomyNot performedNegative13.Invasive tubular carcinoma1Estrogen receptor+/Progesterone receptor+/HER2-Ductal carcinoma in situ37Malignant phyllodes tumorConcurrentMastectomyNegativeNegative

Citation Format: Indu Agarwal, Brian Finkelman, Luis Z. Blanco, Amir Behdad, Kalliopi Siziopikou. Associations and spectrum of genetic mutations in younger patients with breast carcinoma and additional malignancies [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 PS7-74.

ERBB2 amplifications and mutations in 109 advanced breast cancer patients by next-generation sequencing

3565

Background: In advanced breast cancer (ABC) HER2 status is based on ASCO/CAP immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) criteria. Next generation sequencing (NGS) of tissue and blood can detect aberrations in ERBB2 such as copy number gain/amplifications (cng/amp) and mutations. Methods: We retrospectively identified patients (pts) seen at Northwestern University between 2015 and 2019 with ABC and an alteration in ERBB2 identified by tissue and/or circulating tumor DNA (ctDNA) NGS. We included pts with testing by Guardant360, TempusX, and/or FoundationOne platforms. NGS reports were evaluated for non-synonymous mutations and cng/amp. HR and HER2 status were determined based on the most recent pathologic assessment. Mutations were categorized as pathologic if they were consider oncogenic (level 1-2 evidence with direct functional data), likely oncogenic, or predicted oncogenic, based on OncoKB (Chakravarty et al., JCO PO 2017). Results: 109 cases of ABC (6 locally advanced, 103 metastatic) with ERBB2 alterations were identified. Tissue NGS was available from 43%, ctDNA from 72%, and both from 19%. The positive predictive value (PPV) of ERBB2 amp/cng by tissue NGS to predict HER2+ using the gold standard as IHC/FISH was 94% (33/35). The PPV of ERBB2 amp by ctDNA was 93% (40/43). ERBB2 mutations were detected in 52 pts. Of these, 23 pts were considered to harbor pathologic ERBB2 mutations, (19 oncogenic, 2 likely oncogenic, 1 predicted oncogenic) detected by ctDNA and tissue in 4, ctDNA in 16, and tissue in 3 pts. The most frequently detected mutations were V777L and S310. Four pts had co-mutations of ERBB2 V777L and S310F. Disease subtype among those with ERBB2 pathologic mutations was HR+ HER2- in 57%, HER2+ in 26%, and triple negative in 17%. In all patients with serial ctDNA analysis and pathologic ERBB2 mutations, the mutation was detected on the first analysis. Pathologic ERBB2 mutation represented the mutant with the highest mutant allele frequency (MAF) in 30% and top 3 highest MAF in an additional 35%. PIK3CA was co-mutated in 48%. Conclusions: The PPV of ERBB2 amp/cng by tissue and ctDNA NGS was high, and has potential utility for cancers where HER2 IHC/FISH is not standardly assessed or cases where biopsy is challenging. ERBB2 pathologic mutations were found in all breast cancer subtypes. When present, they were identified on the initial ctDNA analysis and often represented a significant clone, supporting its role as a ‘driver mutation’.

Comprehensive Assessment of Changes in Left Ventricular Diastolic Function With Contemporary Breast Cancer Therapy

OBJECTIVES

This study determined the effects of doxorubicin and/or trastuzumab on diastolic function and the relationship between diastolic function and systolic dysfunction.

BACKGROUND

Doxorubicin and trastuzumab can result in left ventricular ejection fraction (LVEF) declines. However, the effects of these therapies on diastolic function remain incompletely defined.

METHODS

In a rigorously phenotyped, longitudinal cohort study of 362 breast cancer participants treated with doxorubicin, doxorubicin followed by trastuzumab, or trastuzumab alone, changes in diastolic function were evaluated using linear models estimated via generalized estimating equations. Associations between baseline and changes in diastolic function with LVEF and longitudinal strain were also determined using generalized estimating equations. The Kaplan-Meier estimator derived the proportion of participants who experienced incident diastolic dysfunction. Cox proportional hazards models estimated the associations between participant characteristics and diastolic dysfunction risk, and between diastolic function and cancer therapy-related cardiac dysfunction risk, defined by an LVEF decline of ≥10% to <50%.

RESULTS

Over a median of 2.1 years (interquartile range [IQR]: 1.3 to 4.2 years), participants treated with doxorubicin or doxorubicin followed by trastuzumab demonstrated a persistent worsening in diastolic function, with reductions in the E/A ratio, lateral and septal e' velocities, and increases in E/e' (p < 0.01). These changes were not observed with trastuzumab alone. Incident abnormal diastolic function grade occurred in 60% at 1 year, 70% by 2 years, and 80% by 3 years. Abnormal diastolic function grade was associated with a subsequent decrease in LVEF (-2.1%; 95% confidence intervals [CI]: -3.1 to -1.2; p < 0.001) and worsening in longitudinal strain (0.6%; 95% CI: 0.1 to 1.1; p = 0.013) over time. Changes in E/e' ratio were modestly associated with worsening longitudinal strain (0.1%; 95% CI: 0.0 to 0.2; p = 0.022).

CONCLUSIONS

A modest, persistent worsening of diastolic function is observed with contemporary breast cancer therapy. Abnormal and worsening diastolic dysfunction is associated with a small risk of subsequent systolic dysfunction. (Cardiotoxicity of Cancer Therapy [CCT]; NCT01173341).

Genetic Variants Associated With Cancer Therapy-Induced Cardiomyopathy

BACKGROUND

Cancer therapy-induced cardiomyopathy (CCM) is associated with cumulative drug exposures and preexisting cardiovascular disorders. These parameters incompletely account for substantial interindividual susceptibility to CCM. We hypothesized that rare variants in cardiomyopathy genes contribute to CCM.

METHODS

We studied 213 patients with CCM from 3 cohorts: retrospectively recruited adults with diverse cancers (n=99), prospectively phenotyped adults with breast cancer (n=73), and prospectively phenotyped children with acute myeloid leukemia (n=41). Cardiomyopathy genes, including 9 prespecified genes, were sequenced. The prevalence of rare variants was compared between CCM cohorts and The Cancer Genome Atlas participants (n=2053), healthy volunteers (n=445), and an ancestry-matched reference population. Clinical characteristics and outcomes were assessed and stratified by genotypes. A prevalent CCM genotype was modeled in anthracycline-treated mice.

RESULTS

CCM was diagnosed 0.4 to 9 years after chemotherapy; 90% of these patients received anthracyclines. Adult patients with CCM had cardiovascular risk factors similar to the US population. Among 9 prioritized genes, patients with CCM had more rare protein-altering variants than comparative cohorts ( P≤1.98e-04). Titin-truncating variants (TTNtvs) predominated, occurring in 7.5% of patients with CCM versus 1.1% of The Cancer Genome Atlas participants ( P=7.36e-08), 0.7% of healthy volunteers ( P=3.42e-06), and 0.6% of the reference population ( P=5.87e-14). Adult patients who had CCM with TTNtvs experienced more heart failure and atrial fibrillation ( P=0.003) and impaired myocardial recovery ( P=0.03) than those without. Consistent with human data, anthracycline-treated TTNtv mice and isolated TTNtv cardiomyocytes showed sustained contractile dysfunction unlike wild-type ( P=0.0004 and P<0.002, respectively).

CONCLUSIONS

Unrecognized rare variants in cardiomyopathy-associated genes, particularly TTNtvs, increased the risk for CCM in children and adults, and adverse cardiac events in adults. Genotype, along with cumulative chemotherapy dosage and traditional cardiovascular risk factors, improves the identification of patients who have cancer at highest risk for CCM.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01173341; AAML1031; NCT01371981.

Can the enumeration of circulating tumor cells (CTCs) and the characterization of circulating tumor DNA (ctDNA) provide insight into organ tropism in metastatic breast cancer (MBC)?

3038

Background: Liquid biopsy provides real-time data about prognosis and actionable mutations in MBC. The aim of this study was to explore the combination of ctDNA analysis and CTCs enumeration in estimating target organs more susceptible to MBC involvement. Methods: This retrospective study analyzed 85 MBC patients (pts) characterized for both CTCs and ctDNA at baseline. CTCs were isolated through the CellSearch kit (Menarini Silicon Biosystems, PA), while ctDNA was analyzed using the Guardant360 NGS-based assay (Guardant Health, CA). Pts with ≥ 5 CTC/7.5 ml of blood were defined as Stage IV aggressive as previously reported (Cristofanilli et al 2019). Statistical associations were explored through uni- and multivariate logistic regression and Fisher’s exact test. Results: 37% of pts were diagnosed with hormone receptor positive (HRpos) MBC, 26% with HER2-positive MBC and 37% with triple negative MBC (TNBC), 28 pts (33%) were defined as stage IV aggressive. The most observed metastatic sites were bone (37%), lymph nodes (29%), lung (27%) and liver (25%). In multivariate analysis, IBC and ESR1 mutations were the only significant factors associated with liver metastases (respectively, OR 0.12, P = 0.038 and OR 24.01, P = 0.019), while no associations were found with respect to lung localizations. Intriguingly, all HRpos MBC pts with ESR1 mutations had bone metastases (P = 0.022), while IBC and Stage IV aggressive were independently associated with bone metastases (respectively OR 0.10, P = 0.006 and OR 19.92, P = 0.003). FGFR1 and NF1 were associated with lymph node localizations (OR 3.68, P = 0.046, OR 4.39, P = 0.031, respectively), while CDK6 and TP53 alterations were associated with serosal involvement (OR 14.34, P = 0.029, OR 0.08, P = 0.031, respectively). Notably, TNBC and IBC were both associated with soft tissue spreading (respectively OR 3.7, P = 0.011, OR 2.79, P = 0.018). Conclusions: These results suggest that ctDNA and CTCs enumeration could give useful insights on MBC organotropism, suggesting a possible role for future monitoring strategies that dynamically focus on high-risk organs defined by tumor biology.

A Clinical Prediction Model to Assess Risk for Pancreatic Cancer Among Patients With New-Onset Diabetes

BACKGROUND & AIMS

Approximately 50% of all patients with pancreatic ductal adenocarcinoma (PDA) develop diabetes mellitus before their cancer diagnosis. Screening individuals with new-onset diabetes might allow earlier diagnosis of PDA. We sought to develop and validate a PDA risk prediction model to identify high-risk individuals among those with new-onset diabetes.

METHODS

We conducted a retrospective cohort study in a population representative database from the United Kingdom. Individuals with incident diabetes after the age of 35 years and 3 or more years of follow-up after diagnosis of diabetes were eligible for inclusion. Candidate predictors consisted of epidemiologic and clinical characteristics available at the time of diabetes diagnosis. Variables with P values <.25 in the univariable analyses were evaluated using backward stepwise approach. Model discrimination was assessed using receiver operating characteristic curve analysis. Calibration was evaluated using the Hosmer-Lemeshow test. Results were internally validated using a bootstrapping procedure.

RESULTS

We analyzed data from 109,385 patients with new-onset diabetes. Among them, 390 (0.4%) were diagnosed with PDA within 3 years. The final model (area under the curve, 0.82; 95% confidence interval, 0.75-0.89) included age, body mass index, change in body mass index, smoking, use of proton pump inhibitors, and anti-diabetic medications, as well as levels of hemoglobin A1C, cholesterol, hemoglobin, creatinine, and alkaline phosphatase. Bootstrapping validation showed negligible optimism. If the predicted risk threshold for definitive PDA screening was set at 1% over 3 years, only 6.19% of the new-onset diabetes population would undergo definitive screening, which would identify patients with PDA with 44.7% sensitivity, 94.0% specificity, and a positive predictive value of 2.6%.

CONCLUSIONS

We developed a risk model based on widely available clinical parameters to help identify patients with new-onset diabetes who might benefit from PDA screening.

Detailed Echocardiographic Phenotyping in Breast Cancer Patients: Associations With Ejection Fraction Decline, Recovery, and Heart Failure Symptoms Over 3 Years of Follow-Up

BACKGROUND

Cardiovascular disease in patients with breast cancer is of growing concern. The longitudinal effects of commonly used therapies, including doxorubicin and trastuzumab, on cardiac remodeling and function remain unknown in this population. We aimed to define the changes in echocardiographic parameters of structure, function, and ventricular-arterial coupling, and their associations with left ventricular ejection fraction (LVEF) and heart failure symptoms.

METHODS

In a longitudinal prospective cohort study of 277 breast cancer participants receiving doxorubicin (Dox), trastuzumab (Tras), or both (Dox+Tras), we obtained 1249 echocardiograms over a median follow-up of 2.0 (interquartile range, 1.0-3.0) years. Left ventricular structure, diastolic and contractile function, and ventricular-arterial coupling measures were quantified in a core laboratory blinded to participant characteristics. We evaluated changes in echocardiographic parameters over time, and used repeated-measures regression models to define their association with LVEF decline and recovery. Linear regression models defined the association between early changes in these parameters and subsequent changes in LVEF and heart failure symptoms.

RESULTS

Overall, 177 (64%) received Dox, 51 (18%) received Tras, and 49 (18%) received Dox+Tras. With Dox, there was a sustained, modest decrease in LVEF over the follow-up duration (1-year change in LVEF -3.6%; 95% confidence interval [CI], -4.4% to -2.8%; 3-year change -3.8%; 95% CI, -5.1% to -2.5%). With Tras, a similar LVEF decline was observed at 1 year (-4.5%; 95% CI, -6.0% to -2.9%) and 3 years (-2.8%; 95%CI, -5.3 to -0.4%). Participants receiving Dox+Tras demonstrated the greatest declines at 1 year (-6.6%; 95% CI, -8.2 to -5.0%), with partial recovery at 3 years (-2.8%; 95% CI, -4.8 to -0.8%). LVEF declines and recovery were associated primarily with changes in systolic volumes, longitudinal and circumferential strain, and ventricular-arterial coupling indices, effective arterial elastance (Ea) and the coupling ratio Ea/Ees_sb, without evidence for effect modification across therapies. Early changes in volumes, strain, and Ea/Ees_sb at 4 to 6 months were associated with 1- and 2-year LVEF changes. Similarly, early changes in strain and Ea were associated with worsening heart failure symptoms at 1 year.

CONCLUSIONS

Doxorubicin and trastuzumab resulted in modest, persistent declines in LVEF at 3 years. Changes in volumes, strain, and ventricular-arterial coupling were consistently associated with concurrent and subsequent LVEF declines and recovery across therapies.