Patient-Reported Outcomes, Tumor Markers, and Survival Outcomes in Advanced GI Cancer

Importance

Patient-reported outcomes (PROs), such as quality of life (QOL) and symptoms, are often associated with clinical outcomes in patients with cancer. In practice, oncologists use serum tumor markers (TMs) (ie, carcinoembryonic antigen [CEA] and carbohydrate antigen 19-9 [CA 19-9]) and imaging to monitor clinical outcomes in patients with gastrointestinal cancer.

Objective

To examine associations of 1-month changes in PROs and TMs with treatment response and survival among patients with gastrointestinal cancer.

Design, Setting, and Participants

This cohort study enrolled patients at Massachusetts General Hospital Cancer Center with at least 1 month follow-up from May 2019 to December 2020. Included patients were beginning first-line systemic therapy, aged 18 years or older, and had been diagnosed with metastatic pancreaticobiliary, colorectal, or gastroesophageal cancer. Data analyses took place from January 2021 to January 2022.

Intervention

PROs were collected, including QOL (Functional Assessment of Cancer Therapy General [FACT-G]), physical symptoms (Edmonton Symptom Assessment System [ESAS]), and psychological symptoms (Patient Health Questionnaire-4 [PHQ4] total, PHQ4-depression, and PHQ4-anxiety), as well as TMs (CEA and CA 19-9), at the time of chemotherapy initiation and 1 month later.

Main Outcomes and Measures

Associations of 1-month changes in PROs and TMs with treatment response (clinical benefit vs disease progression) at first scan, progression-free survival (PFS), and overall survival (OS), adjusted for baseline values using regression models.

Results

This study included 159 patients, with 134 patients (84.3%) evaluable for analysis. Patients had a median (range) age of 64.0 (28.0-84.0) years and 86 (64.2%) were male. One-month PRO changes (FACT-G: OR, 1.07; 95% CI, 1.03-1.11; P = .001; ESAS-total: OR, 0.97; 95% CI, 0.94-1.00; P = .02; ESAS-physical: OR, 0.96; 95% CI, 0.92-1.00; P = .03; PHQ4-depression: OR, 0.67; 95% CI, 0.49-0.92; P = .01) were significantly associated with treatment response, but PHQ4-total or TMs were not. Changes in FACT-G (HR, 0.97; 95% CI, 0.95-0.99; P = .003), ESAS-total (HR, 1.03; 95% CI, 1.01-1.05; P = .004), ESAS-physical (HR, 1.03; 95% CI, 1.00-1.05; P = .02), PHQ4-depression (HR, 1.22; 95% CI, 1.01-1.48; P = .04), and CEA (HR, 1.00; 95% CI, 1.001-1.004; P = .001) were associated with PFS, but changes in PHQ4-total or TMs were not. Changes in ESAS-total (HR, 1.03, 95% CI, 1.01-1.06; P = .006) and ESAS-physical (HR, 1.04, 95% CI, 1.01-1.06; P = .015) were associated with OS, but changes in TMs were not associated with OS.

Conclusions and Relevance

These findings suggest that 1-month changes in PROs can be associated with treatment response and survival in patients with advanced gastrointestinal cancer. Notably, 1-month changes in TMs were not consistently associated with these outcomes. These findings highlight the potential for monitoring early changes in PROs to associate with clinical outcomes while underscoring the need to address the QOL and symptom concerns of patients with advanced cancer.

The Cholangiocarcinoma in the Young (CITY) Study: Tumor Biology, Treatment Patterns, and Survival Outcomes in Adolescent Young Adults With Cholangiocarcinoma

PURPOSE

Increased awareness of the distinct tumor biology for adolescents and young adults (AYAs) with cancer has led to improvement in outcomes for this population. However, in cholangiocarcinoma (CCA), a paucity of data exist on the AYA population. To our knowledge, we present the largest study to date on AYA disease biology, treatment patterns, and survival outcomes in CCA.

METHODS

A multi-institutional cohort of patients with CCA diagnosed with intrahepatic cholangiocarcinoma (ICC) or extrahepatic cholangiocarcinoma (ECC) was used for analysis. Retrospective chart review was conducted on patients who were 50 years old and younger (young; n = 124) and older than 50 years (older; n = 723).

RESULTS

Among 1,039 patients screened, 847 patients met eligibility (72% ICC, 28% ECC). Young patients had a larger median tumor size at resection compared with older patients (4.2 v 3.6 cm; P = .048), more commonly had N1 disease (65% v 43%; P = .040), and were more likely to receive adjuvant therapy (odds ratio, 4.0; 95% CI, 1.64 to 9.74). Tumors of young patients were more likely to harbor an FGFR2 fusion, BRAF mutation, or ATM mutation (P < .05 for each). Young patients were more likely to receive palliative systemic therapy (96% v 69%; P < .001), targeted therapy (23% v 8%; P < .001), and treatment on a clinical trial (31% v 19%; P = .004). Among patients who presented with advanced disease, young patients had a higher median overall survival compared with their older counterparts (17.7 v 13.5 months; 95% CI, 12.6 to 22.6 v 11.4 to 14.8; P = .049).

CONCLUSION

Young patients with CCA had more advanced disease at resection, more commonly received both adjuvant and palliative therapies, and demonstrated improved survival compared with older patients. Given the low clinical trial enrollment and poor outcomes among some AYA cancer populations, data to the contrary in CCA are highly encouraging.

Tumor biology and immune infiltration define primary liver cancer subsets linked to overall survival after immunotherapy

Primary liver cancer is a rising cause of cancer deaths in the US. Although immunotherapy with immune checkpoint inhibitors induces a potent response in a subset of patients, response rates vary among individuals. Predicting which patients will respond to immune checkpoint inhibitors is of great interest in the field. In a retrospective arm of the National Cancer Institute Cancers of the Liver: Accelerating Research of Immunotherapy by a Transdisciplinary Network (NCI-CLARITY) study, we use archived formalin-fixed, paraffin-embedded samples to profile the transcriptome and genomic alterations among 86 hepatocellular carcinoma and cholangiocarcinoma patients prior to and following immune checkpoint inhibitor treatment. Using supervised and unsupervised approaches, we identify stable molecular subtypes linked to overall survival and distinguished by two axes of aggressive tumor biology and microenvironmental features. Moreover, molecular responses to immune checkpoint inhibitor treatment differ between subtypes. Thus, patients with heterogeneous liver cancer may be stratified by molecular status indicative of treatment response to immune checkpoint inhibitors.

Prevalence and Clinicopathologic Characteristics of Hypercalcemia in Patients With Cholangiocarcinoma

This cohort study investigates clinicopathologic and prognostic associations of hypercalcemia in patients with intrahepatic or extrahepatic cholangiocarcinoma.

Molecular Profiling and Treatment Pattern Differences between Intrahepatic and Extrahepatic Cholangiocarcinoma

BACKGROUND

Treatment patterns for intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC) differ, but limited studies exist comparing them. This study examines differences in molecular profiling rates and treatment patterns in these populations, focusing on use of adjuvant, liver-directed, targeted, and investigational therapies.

METHODS

This multi-center collaboration included patients with ICC or ECC treated at one of eight participating institutions. Retrospective data were collected on risk factors, pathology, treatments, and survival. Comparative statistical tests were two-sided.

RESULTS

Among 1,039 patients screened, 847 patients met eligibility (ICC = 611, ECC = 236). Patients with ECC were more likely than those with ICC to present with early-stage disease (53.8% vs 28.0%), undergo surgical resection (55.1% vs 29.8%), and receive adjuvant chemoradiation (36.5% vs 4.2%), (all p < 0.00001). However, they were less likely to undergo molecular profiling (50.3% vs 64.3%) or receive liver directed therapy (17.9% vs 35.7%), targeted therapy (4.7% vs 18.9%), and clinical trial therapy (10.6% vs 24.8%), (all p < 0.001). In patients with recurrent ECC after surgery, the molecular profiling rate was 64.5%. Patients with advanced ECC had a shorter median overall survival than those with advanced ICC (11.8 vs 15.1 months, p < 0.001).

CONCLUSIONS

Patients with advanced ECC have low rates of molecular profiling, possibly in part due to insufficient tissue. They also have low rates of targeted therapy use and clinical trial enrollment. While these rates are higher in advanced ICC, the prognosis for both subtypes of cholangiocarcinoma remains poor, and a pressing need exists for new effective targeted therapies and broader access to clinical trials.

Combined PD-1, BRAF and MEK inhibition in BRAFV600E colorectal cancer: a phase 2 trial

While BRAF inhibitor combinations with EGFR and/or MEK inhibitors have improved clinical efficacy in BRAFV600E colorectal cancer (CRC), response rates remain low and lack durability. Preclinical data suggest that BRAF/MAPK pathway inhibition may augment the tumor immune response. We performed a proof-of-concept single-arm phase 2 clinical trial of combined PD-1, BRAF and MEK inhibition with sparatlizumab (PDR001), dabrafenib and trametinib in 37 patients with BRAFV600E CRC. The primary end point was overall response rate, and the secondary end points were progression-free survival, disease control rate, duration of response and overall survival. The study met its primary end point with a confirmed response rate (24.3% in all patients; 25% in microsatellite stable patients) and durability that were favorable relative to historical controls of BRAF-targeted combinations alone. Single-cell RNA sequencing of 23 paired pretreatment and day 15 on-treatment tumor biopsies revealed greater induction of tumor cell-intrinsic immune programs and more complete MAPK inhibition in patients with better clinical outcome. Immune program induction in matched patient-derived organoids correlated with the degree of MAPK inhibition. These data suggest a potential tumor cell-intrinsic mechanism of cooperativity between MAPK inhibition and immune response, warranting further clinical evaluation of optimized targeted and immune combinations in CRC. ClinicalTrials.gov registration: NCT03668431.

FGFR mRNA Expression in Cholangiocarcinoma and Its Correlation with FGFR2 Fusion Status and Immune Signatures

PURPOSE

Selective FGFR inhibitors are effective against cholangiocarcinomas that harbor gene alterations in FGFR2. Clinical trials suggest that expression of wild-type FGFR mRNA can predict sensitivity to FGFR inhibitors, but this biomarker has not been well characterized in cholangiocarcinoma. This study explores the prevalence of FGFR mRNA overexpression in cholangiocarcinoma, its role in predicting sensitivity to FGFR inhibitors, and its association with immune markers.

EXPERIMENTAL DESIGN

Tissue microarrays of intrahepatic (ICC) and extrahepatic cholangiocarcinomas (ECC) resected between 2004 and 2015 were used to evaluate FGFR1-4 mRNA expression levels by RNA in situ hybridization (ISH). Expression levels of FGFR2 mRNA were correlated with FGFR2 fusion status and with patient outcomes. Immune markers expression was assessed by IHC and CSF1 and CSF1 receptor expression were examined by RNA ISH.

RESULTS

Among 94 patients with resected cholangiocarcinoma, the majority had ICC (77%). FGFR2 fusions were identified in 23% of ICCs and 5% of ECCs. High levels of FGFR mRNA in FGFR2 fusion-negative ICC/ECC were seen for: FGFR1 (ICC/ECC: 15%/0%), FGFR2 (ICC/ECC: 57%/0%), FGFR3 (ICC/ECC: 53%/18%), and FGFR4 (ICC/ECC: 32%/0%). Overall, 62% of fusion-negative cholangiocarcinomas showed high levels of FGFR mRNA. In patients with advanced FGFR2 fusion-positive ICC, high levels of FGFR2 mRNA did not correlate with clinical benefit. FGFR2 fusion-positive tumors showed a paucity of PD-L1 on tumor cells.

CONCLUSIONS

FGFR mRNA overexpression occurs frequently in cholangiocarcinoma in the absence of genetic alterations in FGFR. This study identifies a molecular subpopulation in cholangiocarcinoma for which further investigation of FGFR inhibitors is merited outside currently approved indications.

Abstract C012: Dissecting the reorganization of pancreatic tumor microenvironments after radiation and immunotherapy reveals insights into immunotherapy resistance

Immune checkpoint blockade (ICB) has revolutionized the treatment of many cancers but has been ineffective for the treatment of microsatellite stable (MSS) PDAC. The lack of efficacy of immunotherapies in PDAC is due to: 1) a desmoplastic tumor microenvironment (TME); 2) the presence of suppressive cells, including myeloid derived suppressor cells and regulatory T cells; and 3) the lack of antigen-presenting dendritic cells (DCs) that are important in priming an effective immune response to generate functionally effective tumor antigen-specific T cells. We recently completed a pilot study of dual ICB (Ipilumamab and Nivolumab) with radiation therapy (SBRT 8Gy for 3 fractions) in a cohort of 25 metastatic PDAC patients that had progressed on conventional chemotherapy; this combination conferred an impressive 18% ORR and 29% disease control rate measured on non-irradiated lesions (historical 0% ORR with ICB in PDAC). This led to a phase 2 study in 30 metastatic PDAC patients using this dual modality treatment paradigm. To understand the role of radiation and ICB in altering the PDAC tumor microenvironment we performed single-cell RNA-sequencing and TCR-sequencing (&gt;180k cells), and single-nucleus RNA-sequencing (&gt;300k cells) on 36 tumor biopsies (23 pre-treatment, 13 paired on-treatment between day 10 and 21) from patients undergoing treatment in our phase 2 study. Tumor tissue was taken from distinct tissue sites, including primary tumors in the pancreas, and liver and abdominal wall metastases. We identified distinct tumor cell state distributions within different tissues, and a redistribution of cells from basal/mesenchymal states to classical states after radiation. We identified several state-specific interferon stimulated gene programs thus cataloging distinct responses of epithelial cells with different transcriptional states. Importantly, we found a redistribution of T cells states towards proliferating and exhausted T cells with unique clonality after radiation. Additionally, the myeloid compartment after radiation was enriched for C1QC+ and MHCII+ macrophage subsets, as well as infiltrating CD16/CD16 monocytes and CD14 monocytes, each showing induction of unique sets of interferon stimulated genes (ISGs). We next sought to better understand immunotherapy resistance mechanisms within these PDAC patients despite finding strong ISG induction in several subsets. We analyzed covarying gene programs and identified multicellular communities of cells before and after radiation that underlie interaction networks associated with radiation. Together our data provides the most comprehensive single-cell atlas of paired biopsies to study tumor and immune cell states in the context of radiation and ICB response.

Citation Format: Arnav Mehta, Aparna Parikh, Milan Parikh, Ryan Park, Moshe Sade-Feldman, Lynn Bi, Nicole Carzo, Tarin M. Grillo, Islam Baiev, Olanike Asupoto, Irena Gushterova, Tom LaSalle, Anna Gonye, Emily Blaum, Sebastien Vigneau, Ronan Chaligne, Ana Lako, Thomas Lila, David Nelson, Caroline Porter, Orr Ashenberg, Karthik Jagadesh, William L. Hwang, Christopher Smillie, David P. Ryan, David T. Ting, Theodore Hong, Dana Pe'er, Nir Hacohen. Dissecting the reorganization of pancreatic tumor microenvironments after radiation and immunotherapy reveals insights into immunotherapy resistance [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr C012.

The Clinical Landscape of Cell-Free DNA Alterations in 1,671 Patients with Advanced Biliary Tract Cancer

BACKGROUND

Targeted therapies have transformed clinical management of advanced biliary tract cancer (BTC). Cell-free DNA (cfDNA) analysis is an attractive approach for cancer genomic profiling that overcomes many limitations of traditional tissue-based analysis. We examined cfDNA as a tool to inform clinical management of patients with advanced BTC and generate novel insights into BTC tumor biology.

PATIENTS AND METHODS

We analyzed next-generation sequencing data of 2,068 cfDNA samples from 1,671 patients with advanced BTC generated with Guardant360. We performed clinical annotation on a multi-institutional subset (n=225) to assess intra-patient cfDNA-tumor concordance and the association of cfDNA variant allele fraction (VAF) with clinical outcomes.

RESULTS

Genetic alterations were detected in cfDNA in 84% of patients, with targetable alterations detected in 44% of patients. FGFR2 fusions, IDH1 mutations, and BRAF V600E were clonal in majority of cases, affirming these targetable alterations as early driver events in BTC. Concordance between cfDNA and tissue for mutation detection was high for IDH1 mutations (87%) and BRAF V600E (100%), and low for FGFR2 fusions (18%). cfDNA analysis uncovered novel putative mechanisms of resistance to targeted therapies, including mutation of the cysteine residue (FGFR2 C492F) to which covalent FGFR inhibitors bind. High pre-treatment cfDNA VAF associated with poor prognosis and shorter response to chemotherapy and targeted therapy. Finally, we report the frequency of promising targets in advanced BTC currently under investigation in other advanced solid tumors, including KRAS G12C (1.0%), KRAS G12D (5.1%), PIK3CA mutations (6.8%), and ERBB2 amplifications (4.9%).

CONCLUSIONS

These findings from the largest and most comprehensive study to date of cfDNA from patients with advanced BTC highlight the utility of cfDNA analysis in current management of this disease. Characterization of oncogenic drivers and mechanisms of therapeutic resistance in this study will inform drug development efforts to reduce mortality for patients with BTC.

Abstract LB003: Combined BRAF, MEK, and PD-1 inhibition in BRAFV600E colorectal cancer patients: Correlative studies from a phase 2 trial

Background: Although BRAF inhibitors combined with EGFR and/or MEK inhibitors have improved efficacy in BRAFV600E colorectal cancer (CRC), response rates remain low and clinical benefit is not durable. Preclinical studies suggest that BRAF-targeted therapy in combination with immune checkpoint blockade could enhance anti-tumor activity. We have previously reported on the efficacy from an ongoing phase 2 clinical trial of anti-PD-1 antibody spartalizumab in combination with BRAF inhibitor dabrafenib and MEK inhibitor trametinib in BRAFV600E CRC patients. Of 26 patients, overall response rate (ORR) was 38% (10/26) and compares favorably to the historical controls in BRAFV600E CRC, yet the mechanisms of patient response in this trial need further investigation.

Methods: Single-cell RNA-seq (scRNA-seq) was performed on 23 paired baseline and day 15 tumor biopsies. Patient-derived organoids (PDOs) were generated from baseline tumor biopsies.

Results: scRNA-seq of paired biopsies revealed increased CD8+ T cell infiltration after treatment in patients with better clinical outcome (PFS &gt; 6 months, n=11). From the on- versus pre-treatment differentially expression analysis and gene set enrichment analysis in the tumor epithelial compartment, we observed greater induction and enrichment of immune gene signatures such as antigen processing and presentation, type I and II interferon response, chemokine activity, as well as superior MAPK pathway inhibition with therapy in patients with PFS &gt; 6 months. In comparison, patients with PFS &lt; 6 months (n=12) showed less immune gene upregulation and MAPK pathway inhibition in tumor cells. PDOs treated with dabrafenib and trametinib exhibited gene expression changes that mirrored the changes observed in scRNA-seq of tumor cells in the same patients from which they were derived. BRAF/ERKi treatment in PDOs produced greater MAPK pathway inhibition and immune genes induction than BRAF/MEKi.

Conclusion: Correlative studies of combined anti-PD-1 and BRAF/MEK inhibition suggest that the tumor-intrinsic immune response induced by MAPK pathway inhibition might underlie cooperativity between BRAF-targeted therapy and immune checkpoint blockade. A greater degree of immune gene induction in tumor cells could be enhanced by superior MAPK pathway inhibition, which provides rationale for further clinical studies.

Citation Format: Jun Tian, Jonathan H. Chen, Sherry X. Chao, Karin Pelka, Vjola Jorgji, Islam Baiev, William B. Bradford, Edmond Wong, Princy Sindurakar, Tomonori Oka, Shadmehr Demehri, Nir Hacohen, Ryan B. Corcoran. Combined BRAF, MEK, and PD-1 inhibition in BRAFV600E colorectal cancer patients: Correlative studies from a phase 2 trial [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 LB003.

Changes in Functional Assessment of Cancer Therapy: General (FACT-G) to predict treatment response and survival outcomes in patients with metastatic gastrointestinal (GI) cancer

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Background: The FACT-G contains 27 questions within 4 subscale domains [Physical Well-Being, Social/Family Well-Being, Emotional Well-Being, Functional Well-Being] related to health-related quality of life (QOL) in the past 7 days, with higher scoring indicating better QOL. In this prospective cohort study, we assessed longitudinal FACT-G data with treatment response and survival outcomes among patients with metastatic GI cancer. Methods: From 5/2019-11/2021, we enrolled patients at Massachusetts General Hospital with metastatic GI cancer to study before their treatment start. We collected the FACT-G survey at baseline (start of treatment) and 1-month later. We then used regression models to assess associations of 1-month changes in FACT-G with treatment response and survival outcomes (progression-free survival [PFS] and overall survival [OS]). For treatment response, clinical benefit was defined as decreased or stable tumor burden versus progressive disease at the time of first scan. All models were adjusted for baseline values of each respective variable. Results: We enrolled 203 of 262 patients approached (77.5% enrollment); 160 had 1-month follow-up data (median age = 63.0 years [range: 28.0-84.0 years], 66.3% male, 45.6% pancreaticobiliary cancer). For treatment response, 66.3% experienced a clinical benefit and 33.8% had progressive disease at the time of first scan (mean time to first scan = 2.7 months). Increases in FACT-G Total were predictors for treatment response (OR = 1.05, p = 0.0028), and improved PFS (HR = 0.98, p = 0.026) and OS (HR = 0.98, p = 0.038). Increases in FACT-G Emotional were associated with clinical benefit at the time of first scan (OR = 1.18, p = 0.0024), improved PFS (HR = 0.94, p = 0.023), and improved OS (HR = 0.93, p = 0.012). Improvement in FACT-G Physical were predictors for clinical benefit at time of first scan (OR = 1.08, p = 0.038) and better PFS (HR = 0.96, p = 0.038), while increases in FACT-G Functional were associated with improved PFS (HR = 0.96, p = 0.034) and OS (HR = 0.96, p = 0.019). Finally, changes in FACT-G Social were only associated with treatment response (OR = 1.16, p = 0.011). Conclusions: We found that 1-month increases in FACT-G can predict for treatment response and improved survival outcomes in patients with metastatic GI cancers. Notably, the FACT-G Total and FACT-G Emotional subscore predicted for all three outcomes of interest, while the FACT-G Social only predicted for clinical benefit at first scan. These data support previous findings indicating the possible use of early changes in patient-reported outcomes as a biomarker for early treatment response while emphasizing the growing need to integrate more patient-centric interventions into clinical care for cancer patients. Clinical trial information: NCT04776837.

EGFR Inhibition Potentiates FGFR Inhibitor Therapy and Overcomes Resistance in FGFR2 Fusion-Positive Cholangiocarcinoma

FGFR inhibitors are approved for the treatment of advanced cholangiocarcinoma harboring FGFR2 fusions. However, the response rate is moderate, and resistance emerges rapidly due to acquired secondary FGFR2 mutations or due to other less-defined mechanisms. Here, we conducted high-throughput combination drug screens, biochemical analysis, and therapeutic studies using patient-derived models of FGFR2 fusion-positive cholangiocarcinoma to gain insight into these clinical profiles and uncover improved treatment strategies. We found that feedback activation of EGFR signaling limits FGFR inhibitor efficacy, restricting cell death induction in sensitive models and causing resistance in insensitive models lacking secondary FGFR2 mutations. Inhibition of wild-type EGFR potentiated responses to FGFR inhibitors in both contexts, durably suppressing MEK&sol;ERK and mTOR signaling, increasing apoptosis, and causing marked tumor regressions in vivo. Our findings reveal EGFR-dependent adaptive signaling as an important mechanism limiting FGFR inhibitor efficacy and driving resistance and support clinical testing of FGFR&sol;EGFR inhibitor therapy for FGFR2 fusion-positive cholangiocarcinoma.

SIGNIFICANCE

We demonstrate that feedback activation of EGFR signaling limits the effectiveness of FGFR inhibitor therapy and drives adaptive resistance in patient-derived models of FGFR2 fusion-positive cholangiocarcinoma. These studies support the potential of combination treatment with FGFR and EGFR inhibitors as an improved treatment for patients with FGFR2-driven cholangiocarcinoma.

Changes in patient-reported outcomes (PROs) and tumor markers (TMs) to predict treatment response and survival in patients with metastatic gastrointestinal (GI) cancer

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Background: PROs assessing quality of life (QOL) and symptoms at a single timepoint frequently correlate with clinical outcomes in patients with cancer, yet efforts to understand how longitudinal changes in PROs can predict for treatment outcomes are lacking. In practice, oncologists often use changes in serum TMs (CEA and CA19-9) to monitor patients with GI cancer, and thus we sought to examine associations of 1-month changes in PROs and TMs with treatment response and survival outcomes among patients with advanced GI cancer. Methods: We prospectively enrolled patients with metastatic GI cancer prior to initiating chemotherapy at Massachusetts General Hospital from 5/2019-12/2020. At baseline (start of treatment) and 1-month later, we collected PROs (QOL [Functional Assessment of Cancer Therapy General {FACT-G}], physical symptoms [Edmonton Symptom Assessment System {ESAS}], and psychological symptoms [Patient Health Questionnaire-4 {PHQ-4}]) and TMs. We used regression models to examine associations of 1-month changes in PROs and TMs with treatment response (clinical benefit [defined as decreased or stable tumor burden] or progressive disease at the time of first scan) and survival outcomes (progression-free survival [PFS] and overall survival [OS]), adjusted for baseline values of each respective variable. Results: We enrolled 159 of 191 patients approached (83.2% enrollment); 134 had 1-month follow-up data (median age = 64 years [range: 28 to 84 years], 64.2% male, 46.3% pancreaticobiliary cancer). For treatment response, 63.4% had clinical benefit and 36.6% had progressive disease at the time of first scan (mean time to first scan = 2.01 months). Changes in PROs (ESAS-Total: OR = 0.97, p = 0.022; ESAS-Physical: OR = 0.96, p = 0.027; PHQ-4 depression: OR = 0.67, p = 0.014; FACT-G: OR = 1.07, p = 0.001), but not TMs (CEA: OR = 1.00, p = 0.836 and CA19-9: OR = 1.00, p = 0.796), were associated with clinical benefit at the time of first scan. Changes in ESAS-Total (HR = 1.03, p = 0.004), ESAS-Physical (HR = 1.03, p = 0.021), PHQ-4 depression (HR = 1.22, p = 0.042), FACT-G (HR = 0.97, p = 0.003), and CEA (HR = 1.00, p = 0.001) were predictors of PFS. Changes in ESAS-Total (HR = 1.03, p = 0.006) and ESAS-Physical (HR = 1.04, p = 0.015) were predictors of OS, but 1-month changes in TMs (CEA: HR = 1.00, p = 0.377 and CA19-9: HR = 1.00, p = 0.367) did not significantly predict for OS. Conclusions: We found that 1-month changes in PROs can predict for treatment response and survival outcomes in patients with advanced GI cancers. Notably, 1-month changes in CEA only correlated with PFS, while changes in CA19-9 did not significantly predict treatment response or survival outcomes. These findings highlight the potential for early changes in PROs to predict treatment outcomes while underscoring the need to monitor and address PROs in patients with advanced cancer. Clinical trial information: NCT04776837.

Cell-free DNA captures tumor heterogeneity and driver alterations in rapid autopsies with pre-treated metastatic cancer

In patients with metastatic cancer, spatial heterogeneity of somatic alterations may lead to incomplete assessment of a cancer's mutational profile when analyzing a single tumor biopsy. In this study, we perform sequencing of cell-free DNA (cfDNA) and distinct metastatic tissue samples from ten rapid autopsy cases with pre-treated metastatic cancer. We show that levels of heterogeneity in genetic biomarkers vary between patients but that gene expression signatures representative of the tumor microenvironment are more consistent. Across nine patients with plasma samples available, we are able to detect 62/62 truncal and 47/121 non-truncal point mutations in cfDNA. We observe that mutation clonality in cfDNA is correlated with the number of metastatic lesions in which the mutation is detected and use this result to derive a clonality threshold to classify truncal and non-truncal driver alterations with reasonable specificity. In contrast, mutation truncality is more often incorrectly assigned when studying single tissue samples. Our results demonstrate the utility of a single cfDNA sample relative to that of single tissue samples when treating patients with metastatic cancer.

Changes in patient-reported outcomes (PROs) and tumor markers (TMs) to predict treatment response and survival outcomes in patients with metastatic gastrointestinal (GI) cancer

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Background: PROs assessing quality of life (QOL) and symptoms at a single timepoint frequently correlate with clinical outcomes in patients with cancer, yet efforts to understand how longitudinal changes in PROs can predict for treatment outcomes are lacking. In practice, oncologists often use changes in serum TMs (CEA and CA19-9) to monitor patients with GI cancer, and thus we sought to examine associations of 1-month changes in PROs and TMs with treatment response and survival outcomes among patients with advanced GI cancer. Methods: We prospectively enrolled patients with metastatic GI cancer prior to initiating chemotherapy at Massachusetts General Hospital from 5/2019-12/2020. At baseline (start of treatment) and 1-month later, we collected PROs (QOL [Functional Assessment of Cancer Therapy General {FACT-G}], physical symptoms [Edmonton Symptom Assessment System {ESAS}], and psychological symptoms [Patient Health Questionnaire-4 {PHQ-4}]) and TMs. We used regression models to examine associations of 1-month changes in PROs and TMs with treatment response (clinical benefit [defined as decreased or stable tumor burden] or progressive disease at the time of first scan) and survival outcomes (progression-free survival [PFS] and overall survival [OS]), adjusted for baseline values of each respective variable. Results: We enrolled 159 of 191 patients approached (83.2% enrollment); 134 had 1-month follow-up data (median age = 64 years [range: 28 to 84 years], 64.2% male, 46.3% pancreaticobiliary cancer). For treatment response, 63.4% had clinical benefit and 36.6% had progressive disease at the time of first scan (mean time to first scan = 2.01 months). Changes in PROs (ESAS-Total: OR = 0.97, p = 0.022; ESAS-Physical: OR = 0.96, p = 0.027; PHQ-4 depression: OR = 0.67, p = 0.014; FACT-G: OR = 1.07, p = 0.001), but not TMs (CEA: OR = 1.00, p = 0.836 and CA19-9: OR = 1.00, p = 0.796), were associated with clinical benefit at the time of first scan. Changes in ESAS-Total (HR = 1.03, p = 0.004), ESAS-Physical (HR = 1.03, p = 0.021), PHQ-4 depression (HR = 1.22, p = 0.042), FACT-G (HR = 0.97, p = 0.003), and CEA (HR = 1.00, p = 0.001) were predictors of PFS. Changes in ESAS-Total (HR = 1.03, p = 0.006) and ESAS-Physical (HR = 1.04, p = 0.015) were predictors of OS, but 1-month changes in TMs (CEA: HR = 1.00, p = 0.377 and CA19-9: HR = 1.00, p = 0.367) did not significantly predict for OS. Conclusions: We found that 1-month changes in PROs can predict for treatment response and survival outcomes in patients with advanced GI cancers. Notably, 1-month changes in CEA only correlated with PFS, while changes in CA19-9 did not significantly predict treatment response or survival outcomes. These findings highlight the potential for early changes in PROs to predict treatment outcomes while underscoring the need to monitor and address PROs in patients with advanced cancer.

Minimal Residual Disease Detection using a Plasma-only Circulating Tumor DNA Assay in Patients with Colorectal Cancer

PURPOSE

Detection of persistent circulating tumor DNA (ctDNA) after curative-intent surgery can identify patients with minimal residual disease (MRD) who will ultimately recur. Most ctDNA MRD assays require tumor sequencing to identify tumor-derived mutations to facilitate ctDNA detection, requiring tumor and blood. We evaluated a plasma-only ctDNA assay integrating genomic and epigenomic cancer signatures to enable tumor-uninformed MRD detection.

EXPERIMENTAL DESIGN

A total of 252 prospective serial plasma specimens from 103 patients with colorectal cancer undergoing curative-intent surgery were analyzed and correlated with recurrence.

RESULTS

Of 103 patients, 84 [stage I (9.5%), II (23.8%), III (47.6%), IV (19%)] had evaluable plasma drawn after completion of definitive therapy, defined as surgery only (n = 39) or completion of adjuvant therapy (n = 45). In "landmark" plasma drawn 1-month (median, 31.5 days) after definitive therapy and >1 year follow-up, 15 patients had detectable ctDNA, and all 15 recurred [positive predictive value (PPV), 100%; HR, 11.28 (P < 0.0001)]. Of 49 patients without detectable ctDNA at the landmark timepoint, 12 (24.5%) recurred. Landmark recurrence sensitivity and specificity were 55.6% and 100%. Incorporating serial longitudinal and surveillance (drawn within 4 months of recurrence) samples, sensitivity improved to 69% and 91%. Integrating epigenomic signatures increased sensitivity by 25%-36% versus genomic alterations alone. Notably, standard serum carcinoembryonic antigen levels did not predict recurrence [HR, 1.84 (P = 0.18); PPV = 53.9%].

CONCLUSIONS

Plasma-only MRD detection demonstrated favorable sensitivity and specificity for recurrence, comparable with tumor-informed approaches. Integrating analysis of epigenomic and genomic alterations enhanced sensitivity. These findings support the potential clinical utility of plasma-only ctDNA MRD detection.

Clinical Acquired Resistance to KRASG12C Inhibition through a Novel KRAS Switch-II Pocket Mutation and Polyclonal Alterations Converging on RAS-MAPK Reactivation

Mutant-selective KRAS^G12C inhibitors, such as MRTX849 (adagrasib) and AMG 510 (sotorasib), have demonstrated efficacy in KRAS ^G12C-mutant cancers, including non-small cell lung cancer (NSCLC). However, mechanisms underlying clinical acquired resistance to KRAS^G12C inhibitors remain undetermined. To begin to define the mechanistic spectrum of acquired resistance, we describe a patient with KRAS ^G12C NSCLC who developed polyclonal acquired resistance to MRTX849 with the emergence of 10 heterogeneous resistance alterations in serial cell-free DNA spanning four genes (KRAS, NRAS, BRAF, MAP2K1), all of which converge to reactivate RAS-MAPK signaling. Notably, a novel KRAS ^Y96D mutation affecting the switch-II pocket, to which MRTX849 and other inactive-state inhibitors bind, was identified that interferes with key protein-drug interactions and confers resistance to these inhibitors in engineered and patient-derived KRAS ^G12C cancer models. Interestingly, a novel, functionally distinct tricomplex KRAS^G12C active-state inhibitor RM-018 retained the ability to bind and inhibit KRAS^G12C/Y96D and could overcome resistance. SIGNIFICANCE: In one of the first reports of clinical acquired resistance to KRAS^G12C inhibitors, our data suggest polyclonal RAS-MAPK reactivation as a central resistance mechanism. We also identify a novel KRAS switch-II pocket mutation that impairs binding and drives resistance to inactive-state inhibitors but is surmountable by a functionally distinct KRAS^G12C inhibitor.See related commentary by Pinnelli and Trusolino, p. 1874.This article is highlighted in the In This Issue feature, p. 1861.

The natural history of fibroblast growth factor receptor (FGFR)-altered cholangiocarcinoma (CCA)

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Background: Genetic alterations in the FGFR pathway are emerging as promising therapeutic targets in CCA. The clinical and molecular features of patients (pts) with CCA harboring FGFR genetic alterations are reported here. Methods: A retrospective chart review was performed in pts with CCA who were found to have an FGFR alteration on tumor molecular profiling as part of routine care between 9/2007 and 12/2019. Data on demographics, risk factors, pathology, molecular characteristics, systemic therapies, radiographical response, time on treatment, and overall survival (OS) were collected in a multi-center collaborative effort across seven academic centers. Results: Among 135 pts with FGFR-altered CCA, the median age at diagnosis was 57 years old (range = 25-92 years), and 80 (59.3%) pts were female, 129 (95.6%) had intrahepatic CCA, and 6 (5.6%) had chronic HBV. At presentation, 28.2% of pts had resectable disease, including 65.0% with Stage I-II, 22.5% with Stage III, and 5.0% with Stage IV. At the time of initial diagnosis, CA19-9 was < 35U/mL in 42.6% of pts. Bone metastases were observed in 41 (30.6%) pts with advanced disease. FGFR2 fusions were the most common FGFR alteration (68.2%), followed by FGFR2 mutations (21.5%), FGFR3 mutations (3.7%), FGFR2 rearrangements (1.5%), FGFR1 amplification (1.5%), and FGFR2 amplification (1.5%). The most common FGFR2 fusion partners were BICC1 (28.3%), SORBS1 (4.4%), POC1B (3.3%), and TACC2 (3.3%). The median lines of palliative systemic therapies received was 3 (range = 0-8), and 40/135 (29.6%) pts received a liver-directed therapy. For the 55 (59.8%) pts with FGFR2 fusions who received gemcitabine/cisplatin as first-line palliative systemic therapy, the median time on treatment was 6.2 months (95% CI: 4.1-9.3). The median OS from time of initial diagnosis was 36.1 months (95% CI: 28.3-51.6) in the FGFR2 fusion positive cohort. Among the 92 pts with FGFR2 fusions, 70 (76.1%) pts received an FGFR inhibitor on a clinical trial; 12 (17.1%) were subsequently treated with a second FGFR inhibitor, and 58.3% stayed on the second FGFR inhibitor for ≥4 months. Pts with a BICC1 fusion partner (n = 16) had an overall response rate of 42.9% on FGFR-selective inhibitors compared to 30.8% in non-BICC1 fusion partners (n = 54). Conclusions: Pts with CCA harboring FGFR alterations were found to have a high rate of normal CA19-9, high rate of bone metastases, and short median time on treatment on first-line palliative gemcitabine/cisplatin. Additional comparative studies are necessary to evaluate these findings.

Clinical and molecular features of patients with cholangiocarcinoma harboring FGFR genetic alterations

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Background: Genetic alterations (GAs) in the fibroblast growth factor receptor (FGFR) pathway are emerging as promising therapeutic targets in CCA. The clinical and molecular features of patients (pts) with CCA harboring FGFR GAs are reported here. Methods: A retrospective chart review was performed in pts with CCA who were found to have an FGFR GA on tumor molecular profiling as part of routine care. Data on demographics, risk factors, pathology, systemic therapy, radiographical response, progression free survival (PFS), and overall survival (OS) were collected. Results: Among 65 pts, the median age at diagnosis was 55 years old (range = 27-92), and 38 (58%) pts were female, 63 (97%) had intrahepatic CCA, and 5 (11%) had chronic HBV. At presentation, 37% of pts had resectable disease. Of 47 pts with a known CA 19-9 at the time of initial diagnosis, 21 (45%) had a value < 35U/mL. FGFR2 fusions were the most common FGFR GA (78%), followed by FGFR2 mutations (14%), FGFR3 mutations (4%), FGFR3 fusion (2%) and FGFR1 amplification (2%). The most common fusion partners were BICC1 (20%), POC1B (6%), SORBS1 (6%), DBP (4%), and TACC2 (4%). The most common co-alterations were in ARID1A, CDKN2A/B, TP53, BAP1, IDH1, HER2, BRCA2, and PTEN. The median lines of palliative systemic therapies received was 3 (range = 0-8), and 9/65 (14%) pts had > 1 FGFR inhibitor (FGFRi). For the 30 (46%) pts with FGFR2 fusions who received gemcitabine/platinum as first line palliative systemic therapy, the median PFS was 4.7 months (95% CI: 2.1-6.0). In the overall population, the median OS from time of initial diagnosis was 35.8 months (95% CI:29.7-52.7). Among 46 pts who received an FGFRi on a clinical trial and had ≥ 1 follow-up scan, the overall response rate (ORR) by RECIST v1.1 in pts with FGFR2 fusions, was 35.8% (14/39) on their first FGFRi; ORR was 16.7% (1/6) for pts with FGFR2 mutations. Conclusions: Pts with CCA harboring FGFR GAs were found to have a high rate of normal CA 19-9 and short median PFS on first line gemcitabine/platinum compared to historical controls but additional comparative studies are necessary to evaluate these findings.

TAS-120 Overcomes Resistance to ATP-Competitive FGFR Inhibitors in Patients with FGFR2 Fusion-Positive Intrahepatic Cholangiocarcinoma

ATP-competitive fibroblast growth factor receptor (FGFR) kinase inhibitors, including BGJ398 and Debio 1347, show antitumor activity in patients with intrahepatic cholangiocarcinoma (ICC) harboring activating FGFR2 gene fusions. Unfortunately, acquired resistance develops and is often associated with the emergence of secondary FGFR2 kinase domain mutations. Here, we report that the irreversible pan-FGFR inhibitor TAS-120 demonstrated efficacy in 4 patients with FGFR2 fusion-positive ICC who developed resistance to BGJ398 or Debio 1347. Examination of serial biopsies, circulating tumor DNA (ctDNA), and patient-derived ICC cells revealed that TAS-120 was active against multiple FGFR2 mutations conferring resistance to BGJ398 or Debio 1347. Functional assessment and modeling the clonal outgrowth of individual resistance mutations from polyclonal cell pools mirrored the resistance profiles observed clinically for each inhibitor. Our findings suggest that strategic sequencing of FGFR inhibitors, guided by serial biopsy and ctDNA analysis, may prolong the duration of benefit from FGFR inhibition in patients with FGFR2 fusion-positive ICC. SIGNIFICANCE: ATP-competitive FGFR inhibitors (BGJ398, Debio 1347) show efficacy in FGFR2-altered ICC; however, acquired FGFR2 kinase domain mutations cause drug resistance and tumor progression. We demonstrate that the irreversible FGFR inhibitor TAS-120 provides clinical benefit in patients with resistance to BGJ398 or Debio 1347 and overcomes several FGFR2 mutations in ICC models.This article is highlighted in the In This Issue feature, p. 983.