Circulating tumor DNA dynamics and recurrence risk in patients undergoing curative intent resection of colorectal cancer liver metastases: A prospective cohort study

Prognostic role of postoperative persistence of ctDNA molecular signature after liver resection for colorectal liver metastases: Preliminary results from a prospective study

INTRODUCTION

Liver resection represents the cornerstone treatment for Colo-Rectal Liver Metastases (CRLM), but it is still followed by a high recurrence rate. The identification of a valid and reproducible predictor of recurrence can play a key role in correct and timely management of the disease. In this scenario, liquid biopsy may represent an integrative, less invasive, and easily manageable tool to clinically stratify colorectal cancer patients.We aimed to investigate the prognostic role of persistent circulating tumor DNA (ctDNA) signature on CRLM recurrence after liver resection.

METHODS

A series of 51 consecutive patients undergoing liver resection for CRLM were prospectively enrolled between January 2020 and March 2023. Patients underwent liquid biopsy from peripheral blood samples before and after surgery. Other risk factors for disease recurrence were also investigated.

RESULTS

Twenty-nine patients were found to be positive for one of the clinically relevant molecular alterations detected by NGS, at preoperative (T0) ctDNA analysis. At univariate analysis, total tumor size bigger than 60 mm (p = 0.046, HR 2.486) and postoperative persistence of ctDNA molecular signature (p = 0.024, HR 2.831) were significantly associated with recurrence. Multivariable Cox Regression analysis showed that only postoperative persistence of ctDNA molecular signature was associated with recurrence (p = 0.027, HR 2.766). Similarly, 1-3 yr DFS was significantly lower in the subgroup with persistence of molecular signature at liquid biopsy (100-49.5 % vs 57.1-21.4 %, p = 0.018).

CONCLUSION

Postoperative persistence of ctDNA molecular signature could represent a useful tool to predict recurrence after liver resection for CRLM patients.

A prospective study of methylated ctDNA in patients undergoing treatment for liver metastases from colorectal cancer

BACKGROUND

Decision regarding local treatment of colorectal liver metastases (CRLM) is a multidisciplinary assessment, and liver intervention should be performed when the metastases are deemed resectable. There is no standard biomarker to aid neither this decision nor the postoperative treatment decisions. The present prospective, observational study aimed to investigate the potential clinical utility of a combined tumor-specific and organ-specific methylated circulating DNA assay in the perioperative setting of CRLM.

MATERIAL AND METHODS

The study included 56 cases with CRLM. Blood samples were drawn preoperatively and postoperatively. Multiplex methylation analysis of the markers NPY, KANK1, and GAL3ST3 (meth-ctDNA) was performed using droplet digital PCR.

RESULTS

The assay detected preoperative and postoperative meth-ctDNA in 37 % and 46 % of patients, respectively. Patients with negative preoperative meth-ctDNA had a longer median PFS compared to those with positive preoperative meth-ctDNA (HR = 2.2, 95 % CI 1.2-3.9, p < 0.01). In a multivariate analysis, preoperative negative meth-ctDNA was identified as a strong independent predictor of PFS (HR = 3.3, 95 % CI 1.5-7.2, p < 0.01). Similarly, patients with negative postoperative meth-ctDNA had longer median PFS (HR = 3.0, 95 % CI = 1.6-5.6, p < 0.001) and OS (HR = 4.1, 95 % CI 1.9-9.1, p < 0.001) compared to those with positive postoperative meth-ctDNA.

CONCLUSION

Preoperative meth-ctDNA may serve as an important biomarker to inform the multidisciplinary assessment and treatment planning of CRLM. Negative meth-ctDNA may indicate the optimal timing for liver intervention, whereas positive meth-ctDNA may indicate initiation or re-orientation of chemotherapy, or immediate local intervention. Our results confirm postoperative negative meth-ctDNA as a strong prognostic marker of survival.

Impact of Minimal Residual Disease on Early Recurrence of Liver Metastatic Colorectal Cancer

For patients with resectable colorectal liver metastases (CRLM), the efficacy of adjuvant chemotherapy remains a subject of debate. Several studies have concluded that postoperative circulating tumor DNA (ctDNA) is a marker of minimal residual disease (MRD) and is a useful prognostic factor in patients with nonmetastatic colorectal cancer. However, few studies have explored its application in cases involving metastases. This was an observational study that included CRLM patients who underwent primary and liver tumor resection. By examining targeted sequencing of 50 genes commonly mutated in CRC, we identified at least one somatic mutation in each patient's metastatic liver tumor. Blood samples were obtained before and 1-month after surgery. Fifty-three patients were included, and recurrence was diagnosed in 39 patients. Of those, 13 patients experienced early relapse. ctDNA was detected in 45 patients before surgery and 11 after. All MRD-positive patients experienced recurrence. Among them, nine had early recurrence. MRD-positive patients had poorer recurrence free survival (RFS, p < 0.0001) and overall survival (OS, p < 0.0005). Nine of 13 patients with early recurrence had MRD; however, two of 40 patients without early recurrence also had MRD (p < 0.0001). Among 42 MRD-negative patients, adjuvant chemotherapy had no impact of RFS (p = 0.84) or OS (p = 0.54). MRD proved valuable in predicting the risk of postoperative recurrence in patients with CRLM, particularly because MRD positivity emerged as a significant risk factor for early recurrence. Furthermore, it appears that adjuvant chemotherapy may not effectively improve the prognosis for MRD-negative patients.

Advancing Precision Oncology Through Modeling of Longitudinal and Multimodal Data

Cancer evolves continuously over time through a complex interplay of genetic, epigenetic, microenvironmental, and phenotypic changes. This dynamic behavior drives uncontrolled cell growth, metastasis, immune evasion, and therapy resistance, posing challenges for effective monitoring and treatment. However, today's data-driven research in oncology has primarily focused on cross-sectional analysis using data from a single modality, limiting the ability to fully characterize and interpret the disease's dynamic heterogeneity. Advances in multiscale data collection and computational methods now enable the discovery of longitudinal multimodal biomarkers for precision oncology. Longitudinal data reveal patterns of disease progression and treatment response that are not evident from single-timepoint data, enabling timely abnormality detection and dynamic treatment adaptation. Multimodal data integration offers complementary information from diverse sources for more precise risk assessment and targeting of cancer therapy. In this review, we survey methods of longitudinal and multimodal modeling, highlighting their synergy in providing multifaceted insights for personalized care tailored to the unique characteristics of a patient's cancer. We summarize the current challenges and future directions of longitudinal multimodal analysis in advancing precision oncology.

Utility of circulating tumor DNA to detect minimal residual disease in colorectal cancer: A systematic review and network meta-analysis

Circulating tumor DNA (ctDNA) is a promising biomarker for predicting minimal residual disease (MRD) and guiding treatment decisions in patients with colorectal cancer (CRC). This study aimed to examine the study designs and settings of ongoing clinical trials that use ctDNA to guide treatment decisions and to determine the best timing for detecting MRD in non-metastatic CRC. We searched PubMed, Embase, Web of Science, Cochrane Library, and clinicaltrials.gov for English language records. The ctDNA settings from the clinical trials were categorized by randomization to ctDNA testing, treatment options based on ctDNA results, and the timing of ctDNA testing relative to adjuvant therapy. For prospective studies, a network meta-analysis using a frequentist approach was conducted to examine the pairwise associations between different ctDNA timing strategies and MRD, defined as recurrence, relapse, and progression. The main approaches in ctDNA-based interventional trial designs were categorized as ctDNA-guided treatment, ctDNA-by-treatment, ctDNA-guided surveillance, and ctDNA-enriched adjuvant therapy for guiding treatment decisions, including both escalation and de-escalation strategies, and surveillance. Overall, both preoperative and postoperative ctDNA detection were linked to higher risks of progression, with pooled hazard ratios (95% confidence intervals) of 5.23 (2.10-13.00) and 7.95 (5.30-11.91), respectively. Among the timing strategies, ctDNA testing after adjuvant therapy was the most effective for identifying high-risk patients, strongly suggesting the presence of residual disease. This study comprehensively reviewed the clinical settings of ctDNA testing in ongoing trials and provided evidence supporting the selection of post-adjuvant therapy as the optimal timing for ctDNA testing.

Utility of circulating tumor DNA in secondary liver malignancies: What we know and what is to come

Secondary liver malignancies are a serious and challenging global health concern. Secondary metastasis to the liver is most commonly from colorectal cancer that has metastatically spread through splanchnic circulation. Metastatic diseases can portend poor prognosis due to the progressive nature typically found on detection. Improvements in detection of disease, monitoring therapy response, and monitoring for recurrence are crucial to the improvement in the management of secondary liver malignancies. Assessment of ctDNA in these patient populations poses an opportunity to impact the management of secondary liver malignancies. In this review, we aim to discuss ctDNA, the current literature, and future directions of this technology within secondary liver malignancies.

Circulating tumor DNA as a biomarker of prognosis prediction in colorectal cancer: a systematic review and meta-analysis

OBJECTIVE

Circulating tumor DNA (ctDNA) is increasingly being used as a potential biomarker in colorectal cancer (CRC) patients. However, the role of ctDNA in CRC prognosis prediction remains unclear. The objective is to systematically assess the clinical value of ctDNA in colorectal cancer prognosis prediction throughout the treatment cycle.

METHODS

PubMed, Web of Science, Embase, Cochrane Library, Scopus, and clinical trials.gov database was searched from January 2016 to April 2023. Observational studies and randomized clinical trials reporting on ctDNA and prognostic outcomes in CRC patients were included. Pooled hazard risk ratios (HRs) were calculated for the primary outcomes, relapse-free survival (RFS), and overall survival (OS). Random-effects models were preferred considering the potential heterogeneity.

RESULTS

Sixty-five cohort studies were included. Association between ctDNA and shorter RFS or OS was significant, especially after the full-course treatment recommended by the guidelines (HR = 8.92 [ 95 % CI: 6.02-13.22], P < 0.001, I2 = 73 %; HR = 3.05 [ 95 % CI: 1.72-5.41], P < 0.001, I2 = 48 %) for all types of CRC patients. Despite the presence of heterogeneity, subgroup analyses showed that the cancer type and ctDNA detection assays may be the underlying cause. Besides, ctDNA may detect recurrence earlier than radiographic progression, but no uniform sampling time point between studies might bring bias. However, ctDNA detection did not appear to correlate with pathological complete response achievement in patients with locally advanced rectal cancer.

CONCLUSION

ctDNA detection was significantly associated with poorer prognosis. The potential applications in prognostic prediction are promising and remain to be evaluated in other fields.

Preoperative liquid biopsy for optimal patient selection in metastatic colorectal cancer

OBJECTIVE

In this pilot study, we sought to determine if preoperative circulating tumor DNA could be a useful predictor to avoid futile metastasectomy, predict early postoperative recurrence, and determine optimal chemotherapy duration during the management of patients with resectable metastatic colorectal cancer.

METHODS

Patients from 2021 to 2023 were enrolled prospectively and evaluated with circulating tumor DNA preoperatively and postoperatively for detection of recurrence. Clinicopathologic and treatment factors as well as disease-free survival were compared between those with undetectable versus detectable preoperative circulating tumor DNA.

RESULTS

Twenty-eight patients were evaluated, with a median follow-up time of 24 months. The median preoperative circulating tumor DNA level was 0.16 MTM/mL [0.00, 2.30]. Of the 10 patients (40%) with a preoperative circulating tumor DNA level of zero, 5 patients (50%) recurred between 4 and 18 months postoperatively. Among the 18 patients whose disease recurred, 10 patients (56%) had circulating tumor DNA detected postoperatively. Median change between preoperative and postoperative circulating tumor DNA levels was 0.00 [-0.02, 0.05] in those who did not recur and 0.00 [-7.04, 0.00] in those who recurred. When disease-free survival was evaluated by detectable versus undetectable preoperative circulating tumor DNA levels, there was no difference in disease-free survival estimates (P value = .11). On univariate Cox proportional hazards analysis, the preoperative circulating tumor DNA level, change between preoperative and postoperative circulating tumor DNA levels, and postoperative circulating tumor DNA levels did not influence disease-free survival. However, those with detectable postoperative circulating tumor DNA were 3.96 (95% confidence interval 1.30-12.06) times as likely to recur compared to those with undetectable postoperative circulating tumor DNA.

CONCLUSION

New technologies including use of circulating tumor DNA may help better predict which patients with colorectal liver metastases will undergo futile surgery. Our preliminary findings suggest that postoperative, and not preoperative, circulating tumor DNA is predictive of recurrence following metastasectomy. Use of circulating tumor DNA in guiding operative management should be done in conjunction with high-quality imaging and other serologic markers to determine which patients with colorectal liver metastases are likely to receive durable benefit from operative intervention.

Harnessing the prognostic power of preoperative systemic immune-inflammation index/albumin ratio in hepatocellular carcinoma resection

The recent study by Chen et al, published in the World Journal of Gastroenterology, introduces a groundbreaking assessment tool-the preoperative systemic immune-inflammation index/albumin (SII/ALB) ratio-for patients with hepatocellular carcinoma (HCC) undergoing curative resection. This study not only establishes the independent prognostic significance of the SII/ALB ratio but also incorporates it into a predictive nomogram, enhancing its utility for clinical decision-making. The SII/ALB ratio, by integrating inflammatory and nutritional biomarkers, offers a novel lens through which the prognosis of HCC patients can be viewed, suggesting a more tailored approach to patient management. The development of the nomogram, validated for its accuracy in predicting patient outcomes, marks a pivotal advance, potentially guiding surgical decisions and postoperative care. However, the study's focus on a single-center cohort prompts the need for validation in a broader, more diverse patient population to ensure its applicability across various clinical settings. Moreover, longitudinal studies could elucidate the dynamic changes in SII/ALB post-surgery, offering insights into its potential as a continuous monitor for recurrence and long-term survival. This abstract aim to underscore the critical findings of Chen et al's study while calling for further research to explore the full potential of the SII/ALB ratio in the global management of hepatocellular carcinoma.

Contrast-enhanced intraoperative ultrasound improved hepatic recurrence-free survival in initially unresectable colorectal cancer liver metastases

BACKGROUND

We aimed to evaluate the role of Contrast-enhanced intraoperative ultrasound (CE-IOUS) with perfluorobutane microbubbles (Sonazoid) in improving the prognosis of patients with unresectable colorectal cancer liver metastases (CRLM).

METHODS

A total of 130 Patients with unresectable CRLM who underwent curative hepatic resection at our institute were retrospectively analyzed. Of these 130 enrolled patients, 67 underwent intraoperative ultrasound alone (IOUS group); 63 underwent additional CE-IOUS and IOUS (CE-IOUS group). Normalized inverse probability treatment weighting (IPTW) was employed to balance baseline characteristics between groups. Hepatic recurrence-free survival (HRFS) and overall survival (OS) were compared.

RESULTS

The treatment strategy was altered in 25 patients (25/63, 39.9%) due to the additional use of CE-IOUS. After applying IPTW, the CE-IOUS group exhibited a significantly lower rate of hepatic recurrence (hazard ratio [HR], 0.55; 95% confidence interval [CI] 0.32-0.95; P = 0.032). Subgroup analysis showed that CE-IOUS provided a significant benefit over IOUS in patients with bilobar liver metastases (P = 0.007), or with a number of live tumors < 3 (P = 0.021), or without DLM (P = 0.018), or with extrahepatic metastasis (P = 0.034), or with a minimum of 6 cycles of systemic therapy (P = 0.03).

CONCLUSIONS

CE-IOUS is necessary for unresectable CRLM after preoperative chemotherapy, as it enhances detection accuracy and improves the prognosis of unresectable CRLM patients.

Circulating Tumor DNA as a Marker of Recurrence Risk in Stage III Colorectal Cancer: The α-CORRECT Study

BACKGROUND AND OBJECTIVES

Identification of colorectal cancer (CRC) patients at high risk of recurrence could be of substantial clinical use. We evaluated the association of ctDNA status, using a tumor-informed assay, with recurrence-free survival (RFS).

METHODS

Stage III CRC patients were enrolled between 2016 and 2020. Tumor tissue and serial (every 3 months for years 1-3, biannually for years 4-5) blood samples were collected. Utilizing whole-exome sequencing and selection of 50-200 variants for tumor informed assays, ctDNA status was determined using plasma cell-free DNA.

RESULTS

Of 137 patients enrolled, 124 with 1029 ctDNA results were included in the analyses. Median follow-up was 4.8 years. Plasma ctDNA status was strongly associated with risk of recurrence during the surveillance period (hazard ratio (HR) 49.6, 95% CI: 16.6-148.3; p < 0.0001), and at the postsurgical (HR 9.6, 95% CI: 3.2-29.5) and postdefinitive therapy timepoints (HR: 16.7, 95% CI: 6.9-40.3). The estimated 3-year RFS for ctDNA positive and ctDNA negative patients were, respectively, 54.5% and 96.1% after surgery, and 18.2% and 90.0% after definitive therapy. Multivariable analysis indicated ctDNA but not CEA was strongly prognostic for recurrence.

CONCLUSIONS

Our tumor-informed ctDNA assay was strongly prognostic for recurrence in patients with stage III colorectal cancer at all timepoints.

Circulating Tumor DNA Testing for Minimal Residual Disease and Its Application in Colorectal Cancer

Colorectal cancer (CRC) represents a heterogeneous group of diseases that imposes a considerable global and national health burden. Although most CRC patients are diagnosed at an early stage and undergo potentially curative treatment, a significant proportion experience recurrence. Currently, adjuvant chemotherapy decisions are primarily based on clinicopathological characteristics, which have well-recognized limitations in accurately identifying patients harboring minimal residual disease (MRD), often resulting in unnecessary chemotherapy exposure. Circulating tumor DNA (ctDNA) has emerged as a promising surrogate marker for MRD, offering a more precise approach to identifying patients at risk of recurrence after curative-intent surgery and refining adjuvant chemotherapy decisions. Growing evidence from multiple studies has demonstrated that ctDNA outperforms traditional clinicopathological factors as a marker for MRD. This review synthesizes key studies supporting the role of ctDNA in MRD detection for CRC patients and evaluates clinical trials investigating the application of ctDNA in guiding adjuvant therapy decisions. This emerging strategy holds the potential to transform the adjuvant treatment paradigm in colorectal cancer by optimizing therapeutic precision and minimizing unnecessary treatment.

Safety and efficacy of adjuvant FOLFOX/FOLFIRI with versus without hepatic arterial infusion of floxuridine in patients following colorectal cancer liver metastasectomy (HARVEST trial): A randomized controlled trial

BACKGROUND

Hepatic artery infusion (HAI) chemotherapy, particularly with floxuridine (FUDR), has previously shown effectiveness in improving recurrence-free survival (RFS) in colorectal cancer (CRC) patients with colorectal liver metastases (CRLM). Nonetheless, its adjuvant use alongside modern systemic chemotherapy remains unevaluated.

PATIENTS AND METHODS

The HARVEST trial is an open-label, randomized, controlled study conducted from May 2018 to August 2021. CRC patients with resectable primary tumors and CRLM were recruited and randomized to receive standard systemic chemotherapy only (non-HAI group) or in combination with HAI-FUDR (HAI group). However, due to a FUDR manufacturing shortage, the study was terminated early after enrolling 92 patients. The primary endpoint was the 3-year RFS rate, with secondary endpoints including overall survival (OS), liver-specific RFS, and adverse events.

RESULTS

Of the 92 randomized patients, 77 were included in the modified intention-to-treat analysis. Three-year RFS rates were comparable between the HAI (N = 38) and non-HAI (N = 39) groups (31.4 % vs. 34.4 %; P = 0.28). However, improved 1-year RFS and a longer expected five-year OS were observed in the HAI group. While exploratory subgroup analysis suggested potential RFS benefits for patients with multiple liver metastases, RAS/BRAF mutations, and positive postoperative ctDNA methylation, multivariable analysis did not identify these as independent factors. Safety analysis showed comparable chemotherapy-related adverse events, except for a higher occurrence of ALT elevation in the HAI group.

CONCLUSIONS

While our study showed no significant difference in three-year RFS, adjuvant chemotherapy intensification with HAI-FUDR is feasible and may offer early benefits in RFS and long-term OS. Nonetheless, a larger sample size is needed for validation and identifying which patient subgroup might benefit from this regimen.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03500874.

Liver-First Resection in Patients With Synchronous Colorectal Liver Metastases Is Associated With Inferior Recurrence-Free Survival: Reconsidering the Importance of the Primary Cancer

BACKGROUND

Synchronous colorectal liver metastases may be managed with primary-first, simultaneous, or liver-first resection. Relative oncologic outcomes based on treatment sequencing are understudied.

OBJECTIVE

This study aimed to assess oncologic survival outcomes in patients with synchronous colorectal liver metastases managed with each of the 3 treatment strategies, with respect to early or delayed removal of the primary tumor.

DESIGN

Retrospective analysis of the prospectively maintained database, with 1:1 propensity score matching of relevant clinicopathologic variables comparing liver-first to primary-first/simultaneous approaches.

SETTINGS

Single-institution, tertiary cancer center.

PATIENTS

Patients undergoing curative-intent hepatectomy for synchronous colorectal liver metastases from 2003 to 2019.

MAIN OUTCOME MEASURES

Overall and recurrence-free survival.

RESULTS

Of 151 patients, 23% (n = 35) had liver-first and 77% (n = 116; primary-first = 93 and simultaneous = 23) had primary-first/simultaneous approaches. The median follow-up was 45 months. Recurrence-free survival was worse for liver-first versus primary-first/simultaneous groups (median 12 versus 16 months, p = 0.02), driven by 3-year extrahepatic recurrence-free survival of 19%, 58%, and 50% for liver-first, primary-first, and simultaneous groups, respectively. Three-year overall survival was not significantly different at 86%, 79%, and 86%, respectively. Oncologic outcomes did not differ significantly between primary-first and simultaneous groups (all p > 0.4). Matching yielded 34 clinicopathologically similar patients per group (liver-first = 34, primary-first = 28, simultaneous = 6). The liver-first approach was associated with shorter recurrence-free survival (median 12 versus 23 months, p = 0.004), driven by extrahepatic recurrence-free survival (3 years: 20% versus 55%, p = 0.04). Overall survival was not significantly different at 3 years (79% versus 80%, p = 0.95) or 5 years (59% versus 59%, p > 0.99).

LIMITATIONS

This study has a retrospective design and a limited sample size.

CONCLUSIONS

A liver-first approach is associated with worse recurrence-free survival compared to primary-first or simultaneous resection, driven by extrahepatic recurrence. A prospective study of whether oncologic risk is associated with leaving the primary in situ is needed. Multidisciplinary treatment sequencing and enhanced postoperative surveillance for patients receiving liver-first resection are recommended. See Video Abstract .

LA RESECCIN DEL HGADO PRIMERO EN PACIENTES CON METSTASIS HEPTICAS COLORRECTALES SINCRNICAS SE ASOCIA CON UNA SUPERVIVENCIA INFERIOR SIN RECURRENCIA RECONSIDERACIN DE LA IMPORTANCIA DEL CNCER PRIMARIO

ANTECEDENTES:Las metástasis hepáticas colorrectales sincrónicas se pueden tratar con resección primaria, simultánea o hepática. Los resultados oncológicos relativos basados en la secuenciación del tratamiento están poco estudiados.OBJETIVO:Este estudio tuvo como objetivo evaluar los resultados de supervivencia oncológica en pacientes con metástasis hepáticas colorrectales sincrónicas tratadas con cada una de las tres estrategias de tratamiento, con respecto a la extirpación temprana o tardía del tumor primario.DISEÑO:Análisis retrospectivo de una base de datos mantenida prospectivamente, con coincidencia de propensión 1:1 de variables clínico-patológicas relevantes que comparan enfoques de hígado primero con enfoques primarios primero/simultáneos.AJUSTES:Centro oncológico terciario de una sola institución.PACIENTES:Pacientes sometidos a hepatectomía con intención curativa por metástasis hepáticas colorrectales sincrónicas entre 2003 y 2019.MEDIDAS PRINCIPALES DE RESULTADOS:Supervivencia general y libre de recurrencia.RESULTADOS:De 151 pacientes, el 23% (n=35) tuvo un abordaje hepático primero y el 77% (n=116; primario primero=93 y simultáneo=23) tuvo un abordaje primario primero/simultáneo. La mediana de seguimiento fue de 45 meses. La supervivencia libre de recurrencia fue peor para los grupos de hígado primero versus primario primero/simultáneo (mediana 12 versus 16 meses, p = 0,02), impulsada por la supervivencia libre de recurrencia extrahepática a tres años del 19%, 58% y 50% para grupos de hígado primero, primario primero y simultáneo, respectivamente. La supervivencia general a tres años no fue significativamente diferente: 86%, 79% y 86%, respectivamente. Los resultados oncológicos no difirieron significativamente entre los grupos primario-primero y simultáneo (todos p > 0,4). El emparejamiento produjo 34 pacientes clínico-patológicamente similares por grupo (hígado primero = 34, primario primero = 28/simultáneo = 6). El enfoque de hígado primero se asoció con una supervivencia libre de recurrencia más corta (mediana de 12 frente a 23 meses, p = 0,004), impulsada por la supervivencia libre de recurrencia extrahepática (3 años: 20 % frente a 55 %, p = 0,04). La supervivencia general no fue significativamente diferente a los 3 años (79% versus 80%, p = 0,95) o a los 5 años (59% versus 59%, p > 0,99).LIMITACIONES:Este estudio tiene un diseño retrospectivo y un tamaño de muestra limitado.CONCLUSIONES:Un enfoque de hígado primero se asocia con una peor supervivencia libre de recurrencia en comparación con la resección primaria o simultánea, impulsada por la recurrencia extrahepática. Es necesario un estudio prospectivo sobre si el riesgo oncológico se asocia con dejar el primario in situ . Se recomienda la secuenciación del tratamiento multidisciplinario y una vigilancia posoperatoria mejorada para los pacientes que reciben una primera resección del hígado. (Traducción-Yesenia Rojas-Khalil ).

Enhanced Error Suppression for Accurate Detection of Low-Frequency Variants

The identification of low-frequency variants remains challenging due to the inevitable high error rates of next-generation sequencing (NGS). Numerous promising strategies employ unique molecular identifiers (UMIs) for error suppression. However, their efficiency depends highly on redundant sequencing and quality control, leading to tremendous read waste and cost inefficiency. Here, we describe a novel approach, enhanced error suppression strategy (EES), that addresses these challenges by (1) optimizing data utilization and reducing read waste by utilizing single-read correction that reserves abundant single reads that complement other single reads or single-strand consensus sequences (SSCSs), and (2) effectively enhancing the accuracy of NGS by employing Bayes' theorem. EES significantly improves variant detection accuracy, achieving a background error rate of less than 4.4 × 10-5 per base pair. Additionally, the data utilization rate is dramatically increased, with a 22.9-fold enhancement in duplex consensus sequence (DCS) recovery compared to traditional methodologies. Furthermore, EES demonstrates superior error suppression performance across various base substitutions. In conclusion, EES represents a significant advancement in detecting low-frequency variants by improving data utilization and reducing sequencing errors. It potentially enhances the sensitivity and accuracy of NGS applications, proving highly valuable in clinical and research contexts where precise variant detection is critical.

Early Detection, Precision Treatment, Recurrence Monitoring: Liquid Biopsy Transforms Colorectal Cancer Therapy

Colorectal cancer (CRC) is a significant global health concern. We need ways to detect it early and determine the best treatments. One promising method is liquid biopsy, which uses cancer cells and other components in the blood to help diagnose and treat the disease. Liquid biopsies focus on three key elements: circulating tumor DNA (ctDNA), circulating microRNA (miRNA), and circulating tumor cells (CTC). By analyzing these elements, we can identify CRC in its early stages, predict how well a treatment will work, and even spot signs of cancer returning. This study investigates the world of liquid biopsy, a rapidly growing field. We want to understand how it can help us better recognize the molecular aspects of cancer, improve and diagnostics, tailor treatments to individual patients, and keep track of the disease over the long-term. We explored specific components of liquid biopsy, like extracellular vesicles and cell-free DNA, and how they are used to detect CRC. This review sheds light on the current state of knowledge and the many ways a liquid biopsy can be used in treating colorectal cancer. It can transform patient care, disease management, and clinical outcomes by offering non-invasive cancer-targeting solutions.

Stool and blood biomarkers for colorectal cancer management: an update on screening and disease monitoring

BACKGROUND

Biomarkers have revolutionized the management of colorectal cancer (CRC), facilitating early detection, prevention, personalized treatment, and minimal residual disease (MRD) monitoring. This review explores current CRC screening strategies and emerging biomarker applications.

MAIN BODY

We summarize the landscape of non-invasive CRC screening and MRD detection strategies, discuss the limitations of the current approaches, and highlight the promising potential of novel biomarker solutions. The fecal immunochemical test remained the cornerstone of CRC screening, but its sensitivity has been improved by assays that combined its performance with other stool analytes. However, their sensitivity for advanced adenomas and the patient compliance both remain suboptimal. Blood-based tests promise to increase compliance but require further refinement to compete with stool-based biomarker tests. The ideal scenario involves leveraging blood tests to increase screening participation, and simultaneously promote stool- and endoscopy-based screening among those who are compliant. Once solely reliant on upfront surgery followed by stage and pathology-driven adjuvant chemotherapy, the treatment of stage II and III colon cancer has undergone a revolutionary transformation with the advent of MRD testing after surgery. A decade ago, the concept of using a post-surgical test instead of stage and pathology to determine the need for adjuvant chemotherapy was disruptive. Today, a blood test may be more informative of the need for chemotherapy than the stage at diagnosis.

CONCLUSION

Biomarker research is not just improving, but bringing a transformative change to CRC clinical management. Early detection is not just getting better, but improving thanks to a multi-modality approach, and personalized treatment plans are not just becoming a reality, but a promising future with MRD testing.

Comparing baseline VAF in circulating tumor DNA and tumor tissues predicting prognosis of patients with colorectal cancer liver metastases after curative resection

INTRODUCTION

The prognostic value of baseline variant allele frequency (VAF) in circulating tumor DNA (ctDNA) of colorectal cancer liver metastases (CRLM) patients after curative resection was rarely investigated.

METHODS

A single-center prospective study was performed to investigate the prognostic impact of baseline VAF in ctDNA and matched tumor tissues of CRLM patients after curative resection between May 2019 and May 2021 by the Illumina NovoSeq 6000 platform. The relationship of the tumor burden score (TBS) and the VAF in ctDNA and matched tumor tissues was evaluated by the Pearson correlation method. The survival curves of recurrence-free survival (RFS) and overall survival (OS) were plotted. Factors associated with RFS were calculated using Cox regression analysis, and an integrated prognostic model using significant baseline variables was proposed.

RESULTS

There were 121 patients with baseline ctDNA and matched tumor tissues enrolled in the study. A total of 417 mutations spanning 20 genes were identified in baseline tumor tissues of 119/121 (98.3 %) cases. The overall mutations in tumor tissues were completely covered by ctDNA in 52 of 121(43.0 %) patients. Baseline VAF in ctDNA but not in tumor tissues was significantly correlated to TBS of CRLM (R = 0.36, p < 0.001). Significantly longer RFS but not OS was observed in patients with lower VAF in ctDNA compared to those with higher one (p < 0.001 and p = 0.33 respectively). Multivariate Cox regression analysis showed higher VAF in baseline ctDNA was an independent risk factor for RFS. An integrated prognostic model including baseline metastasis location and VAF in ctDNA outperformed the traditional CRS model in predicting RFS.

CONCLUSION

Baseline VAF in ctDNA but not in tumor tissues influenced RFS of CRLM patients after curative resection.

Survival benefit of adjuvant chemotherapy based on molecular residual disease detection in resected colorectal liver metastases: subgroup analysis from CIRCULATE-Japan GALAXY

BACKGROUND

The prognostic role of circulating tumor DNA (ctDNA)-based molecular residual disease (MRD) detection and its utility for postsurgical risk stratification has been reported in colorectal cancer. In this study, we explored the use of ctDNA-based MRD detection in patients with colorectal liver metastases (CLM), for whom the survival benefit of adjuvant chemotherapy (ACT) after surgical resection remains unclear.

METHODS

Patients with CLM without extrahepatic disease from the GALAXY study (UMIN000039205) were included. The disease-free survival (DFS) benefit of ACT was evaluated in MRD-positive and -negative groups after adjusting for age, gender, number, and size of liver metastases, RAS status, and previous history of oxaliplatin for primary cancer. ctDNA was detected using a personalized, tumor-informed 16-plex polymerase chain reaction-next-generation sequencing (mPCR-NGS) assay. ctDNA-based MRD status was evaluated 2-10 weeks after curative surgery, before the start of ACT.

RESULTS

Among 6061 patients registered in GALAXY, 190 surgically resected CLM patients without any preoperative chemotherapy were included with a median follow-up of 24 months (1-48 months). ctDNA positivity in the MRD window was 32.1% (61/190). ACT was administered to 25.1% (48/190) of patients. In the MRD-positive group, 24-month DFS was higher for patients treated with ACT [33.3% versus not reached, adjusted hazard ratio (HR): 0.07, P < 0.0001]; whereas no benefit of ACT was seen in the MRD-negative group (24-month DFS: 72.3% versus 62.2%, adjusted HR: 0.68, P = 0.371). Multivariate analysis showed that the size of liver metastases (HR: 3.94, P = 0.031) was prognostic of DFS in the MRD-positive group. In the MRD-negative group, however, none of the clinicopathological factors were prognostic of DFS.

CONCLUSIONS

Our data suggest that ACT may offer notable clinical benefits in MRD-positive patients with CLM. MRD status-based risk stratification could be potentially incorporated in future clinical trials for CLM.

Clinical Applications of Circulating Tumor DNA Profiling in GI Cancers

Over the next few years, the analysis of circulating tumor DNA (ctDNA) through liquid biopsy is expected to enter clinical practice and revolutionize the approach to biomarker testing and treatment selection in GI cancers. In fact, growing evidence support the use of ctDNA testing as a noninvasive, effective, and highly specific tool for molecular profiling in GI cancers. Analysis of blood ctDNA has been investigated in multiple settings including early tumor detection, minimal residual disease evaluation, tumor diagnosis and evaluation of prognostic/predictive biomarkers for targeted treatment selection, longitudinal monitoring of treatment response, and identification of resistance mechanisms. Here, we review the clinical applications, advantages, and limitations of ctDNA profiling for precision oncology in GI cancers.

Feasibility of ctDNA in detecting minimal residual disease and predicting recurrence for colorectal cancer liver metastases

Introduction

Approximately 50% of patients diagnosed with colorectal cancer develop colorectal cancer liver metastases (CRLM). Although curative intent liver resection provides 5-year survival of 40-50%, up to 70% of patients develop recurrence of CRLM. Detection of minimal residual disease (MRD) is essential for timely, optimized treatment. This study evaluated the feasibility and utility of using circulating tumor DNA (ctDNA) to identify MRD and predict disease recurrence.

Methods

Patients with CRLM that underwent liver resection and had known KRAS or PIK3CA mutations were retrospectively identified. Serial blood samples were collected every 3 months following surgery for disease surveillance. ctDNA was isolated from the samples and analyzed with digital PCR (dPCR).

Results

KRAS and PIK3CA mutations were identified by dPCR in 29 patients over 115 timepoints. In patients with detectable ctDNA at time of liver resection, 81% (13/16) developed disease recurrence, while 46% (6/13) of the patients with undetectable ctDNA recurred (p=0.064). Presence of ctDNA was detected in 27.6% (8/29) of the initial postoperative samples. Radiologic recurrence was later diagnosed in 100% (8/8) of these patients, while 52% (11/21) who had undetectable ctDNA postoperatively recurred (p=0.026). Detectable ctDNA postoperatively was associated with a shorter disease-free survival (DFS) of 9 months vs 13 months in patients who had undetectable ctDNA (HR 2.95, 95% CI 1.16-7.49; p=0.02).

Conclusion

Liquid biopsy using dPCR can identify low levels of ctDNA, enabling early detection of disease recurrence. Additionally, the presence of ctDNA postoperatively was predictive of recurrence. This study corroborates current literature and provides rational for moving toward a clinical trial using ctDNA and dPCR to detect MRD after CRLM resection.

Evaluation of Molecular Residual Disease by a Fixed Panel in Resectable Colorectal Cancer

PURPOSE

Molecular residual disease (MRD) is a promising biomarker in colorectal cancer (CRC) for prognosis and guiding treatment, while the whole-exome sequencing (WES) based tumor-informed assay is standard for evaluating MRD based on circulating tumor DNA (ctDNA). In this study, we assessed the feasibility of a fixed-panel for evaluating MRD in CRC.

MATERIALS AND METHODS

Seventy-five patients with resectable stage I-III CRC were enrolled. Tumor tissues obtained by surgery, and preoperative and postoperative day 7 blood samples were collected. The ctDNA was evaluated using the tumor-agnostic and tumor-informed fixed assays, as well as the WES-based and panel-based personalized assays in randomly selected patients.

RESULTS

The tumor-informed fixed assay had a higher preoperative positive rate than the tumor-agnostic assay (73.3% vs. 57.3%). The preoperative ctDNA status failed to predict disease-free survival (DFS) in either of the fixed assays, while the tumor-informed fixed assay-determined postoperative ctDNA positivity was significantly associated with worse DFS (hazard ratio [HR], 20.74; 95% confidence interval [CI], 7.19 to 59.83; p < 0.001), which was an independent predictor by multivariable analysis (HR, 28.57; 95% CI, 7.10 to 114.9; p < 0.001). Sub-cohort analysis indicated the WES-based personalized assay had the highest preoperative positive rate (95.1%). The two personalized assays and the tumor-informed fixed assay demonstrated same results in postoperative landmark (HR, 26.34; 95% CI, 6.01 to 115.57; p < 0.001), outperforming the tumor-agnostic fixed panel (HR, 3.04; 95% CI, 0.94 to 9.89; p=0.052).

CONCLUSION

Our study confirmed the prognostic value of the ctDNA positivity at postoperative day 7 by the tumor-informed fixed panel. The tumor-informed fixed panel may be a cost-effective method to evaluate MRD, which warrants further studies in future.

Clinical value of sequential circulating tumor DNA analysis using next-generation sequencing and epigenetic modifications for guiding thermal ablation for colorectal cancer metastases: a prospective study

INTRODUCTION

While thermal ablation is now a standard treatment option for oligometastatic colorectal cancer patients, selecting those who will benefit most from locoregional therapies remains challenging. This proof-of-concept study is the first to assess the feasibility of routine testing of ctDNA before and after thermal ablation with curative intent, analyzed by next-generation sequencing (NGS) and methylation specific digital droplet PCR (ddPCR). Our prospective study primary objective was to assess the prognostic value of ctDNA before thermal ablation.

METHODS

This single-center prospective study from November 2021 to June 2022 included colorectal cancer patients referred for curative-intent thermal ablation. Cell-free DNA was tested at different time points by next-generation sequencing and detection of WIF1 and NPY genes hypermethylation using ddPCR. The ctDNA was considered positive if either a tumor mutation or hypermethylation was detected; recurrence-free survival was used as the primary endpoint.

RESULTS

The study enrolled 15 patients, and a total of 60 samples were analyzed. The median follow-up after ablation was 316 days, and median recurrence-free survival was 250 days. CtDNA was positive for 33% of the samples collected during the first 24 h. The hazard ratio for progression according to the presence of baseline circulating tumor DNA was estimated at 0.14 (CI 95%: 0.03-0.65, p = 0.019). The dynamics are provided, and patients with no recurrence were all negative at H24 for ctDNA.

DISCUSSION

This study shows the feasibility of routine testing of ctDNA before and after thermal ablation with curative intent. We report that circulating tumor DNA is detectable in patients with low tumor burden using 2 techniques. This study emphasizes the potential of ctDNA for discerning patients who are likely to benefit from thermal ablation from those who may not, which could shape future referrals. The dynamics of ctDNA before and after ablation shed light on the need for further research and larger studies.

ctDNA responds to neoadjuvant treatment in locally advanced rectal cancer

BACKGROUND

Liquid biopsy is a minimally invasive procedure investigating tumor mutations.

METHODS

In our retrospective study, we investigated whether molecular therapy monitoring of patients receiving neoadjuvant radio(chemo)therapy on a daily routine is possible in 17 patients with locally advanced rectal cancer. Six patients received short-course radiotherapy (5 × 5 Gy) with subsequent surgery, six patients were treated according RAPIDO protocol with short-course radiotherapy followed by chemotherapy (FOLFOX4) and subsequent surgery and five patients received conventional neoadjuvant radiochemotherapy with 5-FU followed by surgery. Response was assessed by Dworak. Liquid biopsies were taken before and immediately after neoadjuvant radiotherapy to isolate and ultradeeply sequence cell free DNA with a panel of 127 genes. Somatic mutations were determined bioinformatically by comparison with normal DNA from leukocytes to distinguish them from germline variants or aging mutations.

RESULTS

In 12 patients (71%) at least one somatic mutation was detected. In 8/12 patients a decrease and in 4/12 an increase or mixed response in ctDNA was seen. Statistical correlation between ctDNA analysis and clinical response could not be seen.

CONCLUSION

ctDNA is responding to neoadjuvant therapy and liquid biopsy is easily integrated into a daily routine. As part of translational research this protocol leaves room for further investigations.

Association of post-operative ctDNA detection with outcomes of patients with early breast cancers

BACKGROUND

In early breast cancer (EBC) patients, we aimed to determine whether circulating tumor DNA (ctDNA) analysis following primary surgery, before systemic therapy, identified molecular residual disease and was associated with risk of relapse and relapse-free survival (RFS).

METHODS

Plasma was collected, retrospectively, before surgery, 1-14 weeks post-operatively, and before adjuvant therapy, and in a subset of patients after adjuvant therapy. A personalized, tumor-informed, multiplex PCR next generation sequencing assay (Signatera™) was used for ctDNA detection and quantification. The primary objective was to compare RFS and distant recurrence-free survival (DRFS) in patients with detected versus non-detected ctDNA.

RESULTS

A total of 48 patients with EBC (median age 50.5 years) [34 hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-), 5 HER2+, 9 triple-negative breast cancer) were included. ctDNA was detected in 64.5% (20/31) of patients before surgery, and 35.4% (17/48) after surgery. ctDNA detection before surgery was associated with tumor grade (P = 0.019), ctDNA detection after surgery was associated with receptor subtype (P = 0.01). Patients with ctDNA detected after surgery had worse DRFS [hazard ratio = 5.5, 95% confidence interval (CI) 1.1-28.5, P = 0.04]. RFS in patients with ctDNA detected after surgery was worse than in those with lack of ctDNA detection, although not statistically significant (hazard ratio = 3.7, 95% CI 0.9-15.7, P = 0.073). Patients with ctDNA detected preoperatively or post-operatively had a trend towards worse RFS (hazard ratio = 7.8, 95% CI 0.9-63.7, P = 0.05) and DRFS (hazard ratio = 6.8, 95% CI 0.8-57, P = 0.07) compared with those with ctDNA undetected at both timepoints. ctDNA detection anticipated clinical relapse with a median lead time of 16 months.

CONCLUSIONS

In patients with treatment-naive EBC, ctDNA is detectable after surgery. The absence of ctDNA at a single post-surgical timepoint is associated with improved DRFS, supporting the development of future trials studying de-escalation of systemic therapy.

From haystack to high precision: advanced sequencing methods to unraveling circulating tumor DNA mutations

Identifying mutations in cancer-associated genes to guide patient treatments is essential for precision medicine. Circulating tumor DNA (ctDNA) offers valuable insights for early cancer detection, treatment assessment, and surveillance. However, a key issue in ctDNA analysis from the bloodstream is the choice of a technique with adequate sensitivity to identify low frequent molecular changes. Next-generation sequencing (NGS) technology, evolving from parallel to long-read capabilities, enhances ctDNA mutation analysis. In the present review, we describe different NGS approaches for identifying ctDNA mutation, discussing challenges to standardized methodologies, cost, specificity, clinical context, and bioinformatics expertise for optimal NGS application.

Circulating tumor DNA (ctDNA) application in investigation of cancer: Bench to bedside

Now, genomics forms the core of the precision medicine concept. Comprehensive investigations of tumor genomes have made it possible to characterize tumors at the molecular level and, specifically, to identify the fundamental processes that cause condition. A variety of kinds of tumors have seen better outcomes for patients as a result of the development of novel medicines to tackle these genetic-driving processes. Since therapy may exert selective pressure on cancers, non-invasive methods such as liquid biopsies can provide the opportunity for rich reservoirs of crucial and real-time genetic data. Liquid biopsies depend on the identification of circulating cells from tumors, circulating tumor DNA (ctDNA), RNA, proteins, lipids, and metabolites found in patient biofluids, as well as cell-free DNA (cfDNA), which exists in those with cancer. Although it is theoretically possible to examine biological fluids other than plasma, such as pleural fluid, urine, saliva, stool, cerebrospinal fluid, and ascites, we will limit our discussion to blood and solely cfDNA here for the sake of conciseness. Yet, the pace of wider clinical acceptance has been gradual, partly due to the increased difficulty of choosing the best analysis for the given clinical issue, interpreting the findings, and delaying proof of value from clinical trials. Our goal in this review is to discuss the current clinical value of ctDNA in cancers and how clinical oncology systems might incorporate procedures for ctDNA testing.

Trial Protocol of a Phase II Study of mFOLFOXIRI after Metastasectomy in Patients with Oligometastatic Colorectal Cancer (FANTASTIC Study)

Background

The survival benefit of adjuvant chemotherapy after surgical resection of oligometastases from colorectal cancer (CRC) remains unclear. The prognostic role of circulating-tumor DNA (ctDNA) was reported recently and a risk stratification strategy based on monitoring minimal/molecular residual disease (MRD) has been proposed, however, which drug regimen is most effective for ctDNA-positive patients is unknown.

Methods/Design

Oligometastatic CRC patients planning to undergo surgery were registered in this study. After metastasectomy, the registered patients were enrolled in the treatment arm, in which 8 courses of modified-FOLFOXIRI (mFOLFOXIRI; irinotecan 150 mg/m2, oxaliplatin 85 mg/m2, l-leucovorin (l-LV) 200 mg/m2, and 46-h continuous infusion of 5-fluorouracil (5-FU) 2400 mg/m2 every 2 weeks) followed by 4 courses of 5-FU/l-LV are administered. The patients who did not meet the eligibility criteria for the treatment arm or did not consent to mFOLFOXIRI enrolled in the observation arm in which standard of care treatment is provided. Prospective blood collections for retrospective ctDNA analysis are scheduled pre-surgery, and at 28 days, 4 and 7 months after surgery. The primary endpoint is treatment compliance at 8 courses of mFOLFOXIRI and the key secondary endpoints are the ctDNA-positivity rate and survival outcomes in ctDNA-positive and -negative groups. A total of 85 patients will be enrolled from 11 institutions. First patient-in was on July 2020. Accrual completed in February 2024.

Discussion

This study will potentially identify a better treatment strategy for patients with resectable oligometastatic CRC having postsurgical ctDNA positivity, compared to the current standard of care approaches.

Minimal Residual Disease using a Plasma-Only Circulating Tumor DNA Assay to Predict Recurrence of Metastatic Colorectal Cancer Following Curative Intent Treatment

PURPOSE

Minimal residual disease (MRD) detection can identify the recurrence in patients with colorectal cancer (CRC) following definitive treatment. We evaluated a plasma-only MRD assay to predict recurrence and survival in patients with metastatic CRC who underwent curative intent procedures (surgery and/or radiotherapy), with or without (neo)adjuvant chemotherapy. The primary objective of this study was to assess the correlation of postprocedure tumor cell-free DNA detection status with radiographic disease recurrence.

EXPERIMENTAL DESIGN

Preprocedure and postprocedure longitudinal samples were collected from 53 patients and analyzed with a multiomic MRD assay detecting circulating tumor DNA (ctDNA) from genomic and epigenomic signals. Preprocedure and postprocedure ctDNA detection correlated with recurrence-free and overall survival (OS).

RESULTS

From 52 patients, 230/233 samples were successfully analyzed. At the time of data cutoff, 36 (69.2%) patients recurred with median follow-up of 31 months. Detectable ctDNA was observed in 19/42 patients (45.2%) with ctDNA analyzed 3 weeks postprocedure. ctDNA detection 3 weeks postprocedure was associated with shorter median recurrence-free survival (RFS; HR, 5.27; 95% CI, 2.31-12.0; P < 0.0001) and OS (HR, 12.83; 95% CI, 3.6-45.9; P < 0.0001). Preprocedure ctDNA detection status was not associated with RFS but was associated with improved OS (HR, 4.65; 95% CI, 1.4-15.2; P = 0.0111). Undetectable ctDNA preprocedure had notable long-term OS, >90% 3 years postprocedure.

CONCLUSIONS

In this cohort of oligometastatic CRC, detection of ctDNA preprocedure or postprocedure was associated with inferior outcomes even after accounting for known prognostic clinicopathologic variables. This suggests ctDNA may enhance current risk stratification methods helping the evaluation of novel treatments and surveillance strategies toward improving patient outcomes.

Circulating Tumor DNA Predicts Early Recurrence Following Locoregional Therapy for Oligometastatic Colorectal Cancer

(1) Background: Local therapies offer a potentially curative approach for patients with oligometastatic colorectal cancer (CRC). An evidence-based consensus recommendation for systemic therapy following definitive locoregional therapy is lacking. Tumor-informed circulating tumor DNA (ctDNA) might provide information to help guide management in this setting. (2) Methods: A multi-institutional retrospective study was conducted, including patients with CRC that underwent curative-intent locoregional therapy to an isolated site of metastatic disease, followed by tumor-informed ctDNA assessment. The Kaplan-Meier method and log-rank tests were used to compare disease-free survival based on ctDNA results. ctDNA test performance was compared to carcinoembryonic antigen (CEA) test results using McNemar's test. (3) Results: Our study cohort consisted of 87 patients treated with locoregional interventions who underwent ctDNA testing. The initial ctDNA test post-intervention was positive in 28 patients and negative in 59 patients. The median follow-up time was 14.0 months. Detectable ctDNA post-intervention was significantly associated with early disease recurrence, with a median disease-free survival (DFS) of 6.63 months compared to 21.30 months in ctDNA-negative patients (p < 0.001). ctDNA detected a numerically higher proportion of recurrences than CEA (p < 0.097). Post-intervention systemic therapy was not associated with improved DFS (p = 0.745). (4) Conclusions: ctDNA results are prognostically important in oligometastatic CRC, and further prospective studies are urgently needed to define its role in guiding clinical decisions.

Development and validation of a circulating tumor DNA-based optimization-prediction model for short-term postoperative recurrence of endometrial cancer

BACKGROUND

Endometrial cancer (EC) is a common gynecological malignancy that typically requires prompt surgical intervention; however, the advantage of surgical management is limited by the high postoperative recurrence rates and adverse outcomes. Previous studies have highlighted the prognostic potential of circulating tumor DNA (ctDNA) monitoring for minimal residual disease in patients with EC.

AIM

To develop and validate an optimized ctDNA-based model for predicting short-term postoperative EC recurrence.

METHODS

We retrospectively analyzed 294 EC patients treated surgically from 2015-2019 to devise a short-term recurrence prediction model, which was validated on 143 EC patients operated between 2020 and 2021. Prognostic factors were identified using univariate Cox, Lasso, and multivariate Cox regressions. A nomogram was created to predict the 1, 1.5, and 2-year recurrence-free survival (RFS). Model performance was assessed via receiver operating characteristic (ROC), calibration, and decision curve analyses (DCA), leading to a recurrence risk stratification system.

RESULTS

Based on the regression analysis and the nomogram created, patients with postoperative ctDNA-negativity, postoperative carcinoembryonic antigen 125 (CA125) levels of < 19 U/mL, and grade G1 tumors had improved RFS after surgery. The nomogram's efficacy for recurrence prediction was confirmed through ROC analysis, calibration curves, and DCA methods, highlighting its high accuracy and clinical utility. Furthermore, using the nomogram, the patients were successfully classified into three risk subgroups.

CONCLUSION

The nomogram accurately predicted RFS after EC surgery at 1, 1.5, and 2 years. This model will help clinicians personalize treatments, stratify risks, and enhance clinical outcomes for patients with EC.

Pre-hepatectomy dynamic circulating tumor DNA to predict pathologic response to preoperative chemotherapy and post-hepatectomy recurrence in patients with colorectal liver metastases

OBJECTIVE

To evaluate the predictive value of pre-hepatectomy dynamic circulating tumor DNA (ctDNA) on pathologic response to preoperative chemotherapy and recurrence after liver resection for colorectal liver metastases (CRLM).

BACKGROUND

Pathologic response is a predictor of clinical outcomes for patients undergoing hepatectomy for CRLM. Postoperative ctDNA has been proven to be sensitive for recurrence detection. However, few studies investigate the impact of pre-hepatectomy ctDNA on pathologic response and recurrence.

METHODS

Patients with potential resectable CRLM underwent preoperative chemotherapy and hepatectomy between 2018 and 2021 was considered for inclusion. Plasma ctDNA was collected before and after preoperative chemotherapy. Pathologic response was analyzed for all patients after liver resection. Recurrence free survival was compared between patients with different ctDNA status and different pathologic response. The relation between ctDNA and pathologic response was also analyzed.

RESULTS

A total of 114 patients were included. ctDNA was detectable in 108 of 114 patients (94.7%) before chemotherapy, in 56 of 114 patients (49.1%) after chemotherapy. Patients with ctDNA positive at baseline and negative after chemotherapy had significantly longer RFS (median RFS 17 vs 7 months, p = 0.001) and HRFS (median HRFS unreached vs 8 months, p < 0.001) than those with ctDNA persistently positive after chemotherapy. Two patients (1.6%) had a pathologic complete response and 56 patients (45.2%) had a pathologic major response. Post-chemotherapy ctDNA- was associated with improved major pathologic response (53.4% vs 32.1%, p = 0.011). In the multivariable analysis, ctDNA- after chemotherapy (HR 0.51, 95% CI 0.28-0.93), major pathologic response (HR 0.34, 95% CI 0.19-0.62) and surgery combined with radiofrequency ablation (HR 2.62, 95% CI 1.38-5.00) were independently associated with RFS (all p < 0.05).

CONCLUSIONS

Pre-hepatectomy dynamic monitoring of ctDNA could predict pathologic response to preoperative chemotherapy and post-hepatectomy recurrence in CRLM patients. Negative ctDNA after preoperative chemotherapy was associated with better tumor regression grade and recurrence-free survival, which might be used to guide pre-hepatectomy chemotherapy and predict prognosis.

Personalized circulating tumor DNA monitoring improves recurrence surveillance and management after curative resection of colorectal liver metastases: a prospective cohort study

BACKGROUND

Approximately 60% of patients with colorectal liver metastases (CRLM) experience relapse within 2 years after radical resection, previous studies have proven that repeat local treatment (LT) could prolong survival, however, it is difficult to seize the window for LT due to the lack of a high-sensitive surveillance method. In this study, the authors aim to examine the value of longitudinal circulating tumor DNA (ctDNA) in guiding adjuvant chemotherapy, optimizing clinical surveillance strategy, and thereby improving CRLM outcomes.

MATERIALS AND METHODS

The authors conducted a prospective clinical trial using a personalized, tumor-informed ctDNA assay to monitor 60 CRLM patients undergoing resection with curative intent. Formalin-fixed paraffin-embedded tumor samples were collected after surgery. Blood samples were collected before surgery, 30 days after surgery (post-OP), and every third month until relapse or up to 2 years.

RESULTS

A total of 394 plasma samples from 60 eligible patients were analyzed, with a median follow-up time of 31.3 months. Landmark analyses revealed that detectable ctDNA at post-OP (HR, 4.8), postadjuvant chemotherapy (HR, 6.0), and end-of-treatment (HR, 5.6) were associated with higher recurrence risk ( P <0.001). Post-OP ctDNA positivity served as the only independent prognostic marker in the multivariant analysis (HR, 5.1; P <0.001). Longitudinal ctDNA analysis identified relapsed patients at both sensitivity and specificity of 100%. Most (75%) patients were found with radiological relapse within 6 months after the first detectable ctDNA with a median lead time of 3.5 months. In relapsed patients, 73.2% had oligometastatic disease and 61% were liver-restricted, of which 72.0% received repeat LTs, and 60.0% achieved a secondary no evidence of disease status.

CONCLUSIONS

Longitudinal ctDNA monitoring assists in early prediction of relapse, and thereby improves survival of CRLM patients by increased secondary resection rate and secondary no evidence of disease rate.

Multi-Institutional Study Evaluating the Role of Circulating Tumor DNA in the Management of Appendiceal Cancers

PURPOSE

Conventional surveillance methods are poorly sensitive for monitoring appendiceal cancers (AC). This study investigated the utility of circulating tumor DNA (ctDNA) in evaluating systemic therapy response and recurrence after surgery for AC.

METHODS

Patients from two specialized centers who underwent tumor-informed ctDNA testing (Signatera) were evaluated to determine the association between systemic therapy and ctDNA detection. In addition, the accuracy of ctDNA detection during surveillance for the diagnosis of recurrence after complete cytoreductive surgery (CRS) for grade 2-3 ACs with peritoneal metastases (PM) was investigated.

RESULTS

In this cohort of 94 patients with AC, most had grade 2-3 tumors (84.0%) and PM (84.0%). Fifty patients completed the assay in the presence of identifiable disease, among which ctDNA was detected in 4 of 7 (57.1%), 10 of 16 (62.5%), and 19 of 27 (70.4%) patients with grade 1, 2, and 3 diseases, respectively. Patients who had recently received systemic chemotherapy had ctDNA detected less frequently (7 of 16 [43.8%] v 26 of 34 [76.5%]; odds ratio, 0.22 [95% CI, 0.06 to 0.82]; P = .02). Among 36 patients with complete CRS for grade 2-3 AC-PM, 16 (44.4%) developed recurrence (median follow-up, 19.6 months). ctDNA detection was associated with shorter recurrence-free survival (median 11.3 months v not reached; hazard ratio, 14.1 [95% CI, 1.7 to 113.8]; P = .01) and showed high accuracy for the detection of recurrence (sensitivity 93.8%, specificity 85.0%). ctDNA was more sensitive than carcinoembryonic antigen (62.5%), CA19-9 (25.0%), and CA125 (18.8%) and was the only elevated biomarker in four (25%) patients with recurrence.

CONCLUSION

This study revealed a reduced ctDNA detection frequency after systemic therapy and accurate recurrence assessment after CRS. These findings underscore the role of ctDNA as a predictive and prognostic biomarker for grade 2-3 AC-PM management.

Bridging horizons beyond CIRCULATE-Japan: a new paradigm in molecular residual disease detection via whole genome sequencing-based circulating tumor DNA assay

Circulating tumor DNA (ctDNA) is the fraction of cell-free DNA in patient blood that originates from a tumor. Advances in DNA sequencing technologies and our understanding of the molecular biology of tumors have increased interest in exploiting ctDNA to facilitate detection of molecular residual disease (MRD). Analysis of ctDNA as a promising MRD biomarker of solid malignancies has a central role in precision medicine initiatives exemplified by our CIRCULATE-Japan project involving patients with resectable colorectal cancer. Notably, the project underscores the prognostic significance of the ctDNA status at 4 weeks post-surgery and its correlation to adjuvant therapy efficacy at interim analysis. This substantiates the hypothesis that MRD is a critical prognostic indicator of relapse in patients with colorectal cancer. Despite remarkable advancements, challenges endure, primarily attributable to the exceedingly low ctDNA concentration in peripheral blood, particularly in scenarios involving low tumor shedding and the intrinsic error rates of current sequencing technologies. These complications necessitate more sensitive and sophisticated assays to verify the clinical utility of MRD across all solid tumors. Whole genome sequencing (WGS)-based tumor-informed MRD assays have recently demonstrated the ability to detect ctDNA in the parts-per-million range. This review delineates the current landscape of MRD assays, highlighting WGS-based approaches as the forefront technique in ctDNA analysis. Additionally, it introduces our upcoming endeavor, WGS-based pan-cancer MRD detection via ctDNA, in our forthcoming project, SCRUM-Japan MONSTAR-SCREEN-3.

Multimodal Treatment of Metastatic Rectal Cancer in a Young Patient: Case Report and Literature Review

Metastatic colorectal cancer requires a multidisciplinary and individualized approach. Herein, we reported the case of a young woman diagnosed with metastatic rectal cancer who received an individualized multimodal treatment strategy that resulted in a remarkable survival. There were several particular aspects of this case, such as the early onset of the disease, the successful use of conversion therapy, the application of liquid biopsy to guide treatment, and the specific nature of the bone metastasis. To offer more insights for navigating such challenges in patients with metastatic colorectal cancer, we have conducted a literature review to find more data related to the particularities of this case. The incidence of early onset colorectal cancer is on the rise. Data suggests that it differs from older-onset colorectal cancer in terms of its pathological, epidemiological, anatomical, metabolic, and biological characteristics. Conversion therapy and surgical intervention provide an opportunity for cure and improve outcomes in metastatic colorectal cancer. It is important to approach each case individually, as every patient with limited liver disease should be considered as a candidate for secondary resection. Moreover, liquid biopsy has an important role in the individualized management of metastatic colorectal cancer patients, as it offers additional information for treatment decisions.

Analytical validation of NeXT Personal®, an ultra-sensitive personalized circulating tumor DNA assay

We describe the analytical validation of NeXT Personal®, an ultra-sensitive, tumor-informed circulating tumor DNA (ctDNA) assay for detecting residual disease, monitoring therapy response, and detecting recurrence in patients diagnosed with solid tumor cancers. NeXT Personal uses whole genome sequencing of tumor and matched normal samples combined with advanced analytics to accurately identify up to ~1,800 somatic variants specific to the patient's tumor. A personalized panel is created, targeting these variants and then used to sequence cell-free DNA extracted from patient plasma samples for ultra-sensitive detection of ctDNA. The NeXT Personal analytical validation is based on panels designed from tumor and matched normal samples from two cell lines, and from 123 patients across nine cancer types. Analytical measurements demonstrated a detection threshold of 1.67 parts per million (PPM) with a limit of detection at 95% (LOD95) of 3.45 PPM. NeXT Personal showed linearity over a range of 0.8 to 300,000 PPM (Pearson correlation coefficient = 0.9998). Precision varied from a coefficient of variation of 12.8% to 3.6% over a range of 25 to 25,000 PPM. The assay targets 99.9% specificity, with this validation study measuring 100% specificity and in silico methods giving us a confidence interval of 99.92 to 100%. In summary, this study demonstrates NeXT Personal as an ultra-sensitive, highly quantitative and robust ctDNA assay that can be used to detect residual disease, monitor treatment response, and detect recurrence in patients.

Role of Circulating Tumor DNA Among Patients with Colorectal Peritoneal Metastases

PURPOSE

This was a review of circulating tumor DNA (ctDNA) in patients with peritoneal metastases from colorectal cancer.

METHODS

We searched the PubMed database for studies reporting detection of ctDNA in patients with colorectal cancer (CRC) and with peritoneal metastases (PM) from colorectal cancer (CRPM). We extracted data on the population included, number of subjects, study design, type of ctDNA assay used and schedule, and the major findings from these publications.

RESULTS

We identified 13 studies for review investigating ctDNA, using a variety of ctDNA assays, among 1787 patients with CRC without PM, as well as four eligible published and one unpublished (in press) studies, which included 255 patients with PM from any primary site and 61 patients with CRPM. Among the 13 studies investigating ctDNA among CRC without PM, posttreatment surveillance ctDNA was associated with recurrence and was generally more sensitive than imaging or tumor markers. Among the five studies including patients with PM, ctDNA was not universally able to detect the presence of PM, but when present, ctDNA predicted worse outcomes.

CONCLUSION

Circulating-tumor DNA is a potentially useful surveillance tool for patients with CRC. However, the sensitivity of ctDNA to detect CRPM is variable and warrants further inquiry.

Methylated ctDNA predicts early recurrence risk in patients undergoing resection of initially unresectable colorectal cancer liver metastases

Background

Patients with initially unresectable colorectal cancer liver metastases (IU-CRLM) might benefit from using an effective systemic treatment followed by resection of liver metastases but the curative success rate is quite low. Indeed, nearly one-third of patients exhibit early recurrence within the first 6 months after surgery, and these individuals often have poor overall survival.

Objectives

This study aims to clarify the application value of serial circulating tumor DNA (ctDNA) analysis in predicting the clinical outcome of IU-CRLM patients following liver metastasectomy.

Design

A retrospective study was conducted on a cohort of patients with IU-CRLM between February 2018 and April 2021.

Methods

Plasma samples at different time points during CRLM treatment [baseline (BL), preoperation (PRE), postoperation (POST), end-of-treatment (EOT), and progressive disease (PD)] were retrospectively collected from patients with initially unresectable CRLM enrolled at the Sun Yat-sen University Cancer Center. Dynamic changes of SEPTIN 9 (SEPT9) and Neuropeptide Y (NPY) methylated circulating tumor DNA (MetctDNA) levels in serial plasma samples were detected using droplet-digital PCR (ddPCR).

Results

SEPT9 and NPY genes were hypermethylated in colon cancer cell lines and tissues while no difference was observed between primary and metastatic tumors. Patients with MetctDNA positive at POST or EOT had significantly lower recurrence-free survival (RFS) compared to patients with MetctDNA negative at these time points [POST: Hazard ratio (HR) 9.44, 95% confidence interval (CI) 5.15-17.30, p < 0.001; EOT: HR 11.48, 95% CI 3.27-40.31, p < 0.001]. Multivariate analysis demonstrated that POST (OR 33.96, 95% CI 4.03-286.10, p = 0.001) and EOT (OR 18.36, 95% CI 1.14-295.71, p = 0.04) MetctDNA was an independent risk factor for early recurrence. Time-dependent receiver operating characteristic curve (T-ROC) analysis revealed that area under the curve (AUC) value was greatest at the relapse time point of 6 months post-intervention, with POST-AUC and EOT-AUC values of 0.74 (95% CI 0.66-0.81) and 0.73 (95% CI 0.53-0.94), respectively. Serial MetctDNA analysis showed that RFS was significantly lower in patients with no MetctDNA clearance compared with those with MetctDNA clearance (HR 26.05, 95% CI 4.92-137.81, p < 0.001).

Conclusion

Our study confirmed that serial ctDNA analysis of NPY and SEPT9 gene methylation could effectively predict early recurrence in IU-CRLM patients, especially at POST and EOT.

Sensitive and Specific Analyses of Colorectal Cancer Recurrence through Multiplex superRCA Mutation Detection in Blood Plasma

Mutation analysis of circulating tumor DNA (ctDNA) has applications in monitoring of colorectal cancer (CRC) patients for recurrence. Considering the low tumor fraction of ctDNA in cell-free DNA (cfDNA) isolated from blood plasma, the sensitivity of the detection method is important. Here, plasma DNA collected at diagnosis and follow-up from 25 CRC patients was analyzed using a multiplex superRCA mutation detection assay. The assay was also performed on genomic DNA (gDNA) from tumor and normal tissue from 20 of these patients. The lower limit of detection for most sequence variants was in the range of 10-5, while when analyzing cfDNA from plasma with a typical input of 33 ng, the practical detection limit was ~10-4 or 0.01% mutant allele frequency (MAF). In 17 of 19 patients with identified hotspot mutations in tumor gDNA, at least one hotspot mutation could be detected in plasma DNA at the time of diagnosis. The MAF increased at subsequent time points in four of the patients who experienced a clinical relapse. Multiplex superRCA analysis of the remaining six patients did not reveal any hotspot mutations. In conclusion, multiplex superRCA assays proved suitable for monitoring CRC patients by analyzing hotspot mutations in cfDNA, and dynamic changes in MAF were observed in patients with clinical relapse.

Circulating tumor DNA analysis predicts recurrence and avoids unnecessary adjuvant chemotherapy in I-IV colorectal cancer

Background

Circulating tumor DNA (ctDNA) has emerged as a biomarker that can define the risk of recurrence after curative-intent surgery for patients with colorectal cancer (CRC). However, beyond the predictive power of postoperative ctDNA detection, the efficacy and potential limitations of ctDNA detection urgently need to be fully elucidated in a large cohort of CRC.

Objectives

To define potentially cured CRC patients through ctDNA monitoring following surgery.

Design

A prospective, multicenter, observational study.

Methods

We enrolled 309 patients with stages I-IV CRC who underwent definitive surgery. Tumor tissues were sequenced by a custom-designed next-generation sequencing panel to identify somatic mutations. Plasma was analyzed using a ctDNA-based molecular residual disease (MRD) assay which integrated tumor-genotype-informed and tumor-genotype-naïve ctDNA analysis. The turnaround time of the assay was 10-14 days.

Results

Postoperative ctDNA was detected in 5.4%, 13.8%, 15%, and 30% of patients with stage I, II, III, and IV disease, respectively, and in 17.5% of all longitudinal samples. Patients with positive postsurgery MRD had a higher recurrence rate than those with negative postsurgery MRD [hazard ratio (HR), 13.17; p < 0.0001], producing a sensitivity of 64.6%, a specificity of 94.8%, a positive predictive value (PPV) of 75.6%, and a negative predictive value (NPV) of 91.5%. Furthermore, patients with positive longitudinal MRD also had a significantly higher recurrence rate (HR, 14.44; p < 0.0001), with increased sensitivity (75.0%), specificity (94.9%), PPV (79.6%), and NPV (93.4%). Subgroup analyses revealed that adjuvant therapy did not confer superior survival for patients with undetectable or detectable MRD. In addition, MRD detection was less effective in identifying lung-only and peritoneal metastases.

Conclusion

Postoperative ctDNA status is a strong predictor of recurrence independent of stage and microsatellite instability status. Longitudinal undetectable MRD could be used to define the potentially cured population in CRC patients undergoing curative-intent surgery.

Analysis of circulating tumor DNA identifies distinct therapeutic response to intraperitoneal and intravenous paclitaxel plus S-1 in gastric cancer patients with peritoneal metastasis

BACKGROUND

Circulating tumor DNA (ctDNA) is a promising technique for predicting curative effects and monitoring tumor recurrence. The utility of ctDNA for gastric cancer with peritoneal dissemination remains elusive.

OBJECTIVES

To assess the feasibility of ctDNA in predicting tumor response to chemotherapy in gastric cancer with peritoneal dissemination.

DESIGN

This was a prospective study.

METHODS

We enrolled 30 patients with gastric cancer peritoneal metastasis, treated with intraperitoneal and intravenous paclitaxel plus S-1. Peripheral blood samples of patients were prospectively collected at baseline, after treatment initiation accompanied by computed tomography scan and disease progression. Mutational profiles from ctDNA were analyzed to evaluate its association with chemotherapeutic response.

RESULTS

Tumor protein 53 (TP53) was the most frequently altered gene at baseline blood samples. Although baseline TP53 mutation was not related to therapeutic response, patients with TP53 mutation had worse progression-free survival (PFS) and overall survival (OS). Additionally, baseline ctDNA content fraction (CCF) was found to be significantly lower in responders than non-responders. Meanwhile, patients with high CCF had a trend of worse PFS and OS. Combining TP53 alteration and CCF, the prognosis of TP53-wt patients could be further stratified. Patients with CCF-low_TP53-wt had markedly longer survival than those with CCF-high_TP53-wt.

CONCLUSION

Our study highlighted the significance of ctDNA in predicting potential clinical outcomes in gastric cancer patients during chemotherapy.

TRIAL REGISTRATION

ChiCTR-IIR-16009802 (Chinese Clinical Trial Registry).

Exploring Potential Epigenetic Biomarkers for Colorectal Cancer Metastasis

Metastatic progression is a complex, multistep process and the leading cause of cancer mortality. There is growing evidence that emphasises the significance of epigenetic modification, specifically DNA methylation and histone modifications, in influencing colorectal (CRC) metastasis. Epigenetic modifications influence the expression of genes involved in various cellular processes, including the pathways associated with metastasis. These modifications could contribute to metastatic progression by enhancing oncogenes and silencing tumour suppressor genes. Moreover, specific epigenetic alterations enable cancer cells to acquire invasive and metastatic characteristics by altering cell adhesion, migration, and invasion-related pathways. Exploring the involvement of DNA methylation and histone modification is crucial for identifying biomarkers that impact cancer prediction for metastasis in CRC. This review provides a summary of the potential epigenetic biomarkers associated with metastasis in CRC, particularly DNA methylation and histone modifications, and examines the pathways associated with these biomarkers.

Personalizing adjuvant therapy for patients with colorectal cancer

The current standard-of-care adjuvant treatment for patients with colorectal cancer (CRC) comprises a fluoropyrimidine (5-fluorouracil or capecitabine) as a single agent or in combination with oxaliplatin, for either 3 or 6 months. Selection of therapy depends on conventional histopathological staging procedures, which constitute a blunt tool for patient stratification. Given the relatively marginal survival benefits that patients can derive from adjuvant treatment, improving the safety of chemotherapy regimens and identifying patients most likely to benefit from them is an area of unmet need. Patient stratification should enable distinguishing those at low risk of recurrence and a high chance of cure by surgery from those at higher risk of recurrence who would derive greater absolute benefits from chemotherapy. To this end, genetic analyses have led to the discovery of germline determinants of toxicity from fluoropyrimidines, the identification of patients at high risk of life-threatening toxicity, and enabling dose modulation to improve safety. Thus far, results from analyses of resected tissue to identify mutational or transcriptomic signatures with value as prognostic biomarkers have been rather disappointing. In the past few years, the application of artificial intelligence-driven models to digital images of resected tissue has identified potentially useful algorithms that stratify patients into distinct prognostic groups. Similarly, liquid biopsy approaches involving measurements of circulating tumour DNA after surgery are additionally useful tools to identify patients at high and low risk of tumour recurrence. In this Perspective, we provide an overview of the current landscape of adjuvant therapy for patients with CRC and discuss how new technologies will enable better personalization of therapy in this setting.

Plasma Assay of Cell-Free Methylated DNA Markers of Colorectal Cancer: A Tumor-Agnostic Approach to Monitor Recurrence and Response to Anticancer Therapies

BACKGROUND

Radiographic surveillance of colorectal cancer (CRC) after curative-intent therapy is costly and unreliable. Methylated DNA markers (MDMs) detected primary CRC and metastatic recurrence with high sensitivity and specificity in cross-sectional studies. This study evaluated using serial MDMs to detect recurrence and monitor the treatment response to anti-cancer therapies.

METHODS

A nested case-control study was drawn from a prospective cohort of patients with CRC who completed curative-intent therapy for CRC of all stages. Plasma MDMs were assayed vis target enrichment long-probe quantitative-amplified signal assays, normalized to B3GALT6, and analyzed in combination with serum carcinoembryonic antigen to yield an MDM score. Clinical information, including treatment and radiographic measurements of the tumor burden, were longitudinally collected.

RESULTS

Of the 35 patients, 18 had recurrence and 17 had no evidence of disease during the study period. The MDM score was positive in 16 out of 18 patients who recurred and only 2 of the 17 patients without recurrence. The MDM score detected recurrence in 12 patients preceding clinical or radiographic detection of recurrent CRC by a median of 106 days (range 90-232 days).

CONCLUSIONS

Plasma MDMs can detect recurrent CRC prior to radiographic detection; this tumor-agnostic liquid biopsy approach may assist cancer surveillance and monitoring.

Circulating Tumor DNA Is a Variant of Liquid Biopsy with Predictive and Prognostic Clinical Value in Breast Cancer Patients

This paper introduces the reader to the field of liquid biopsies and cell-free nucleic acids, focusing on circulating tumor DNA (ctDNA) in breast cancer (BC). BC is the most common type of cancer in women, and progress with regard to treatment has been made in recent years. Despite this, there remain a number of unresolved issues in the treatment of BC; in particular, early detection and diagnosis, reliable markers of response to treatment and for the prediction of recurrence and metastasis, especially for unfavorable subtypes, are needed. It is also important to identify biomarkers for the assessment of drug resistance and for disease monitoring. Our work is devoted to ctDNA, which may be such a marker. Here, we describe its main characteristics and potential applications in clinical oncology. This review considers the results of studies devoted to the analysis of the prognostic and predictive roles of various methods for the determination of ctDNA in BC patients. Currently known epigenetic changes in ctDNA with clinical significance are reviewed. The possibility of using ctDNA as a predictive and prognostic marker for monitoring BC and predicting the recurrence and metastasis of cancer is also discussed, which may become an important part of a precision approach to the treatment of BC.

ctDNA-guided adjuvant treatment after radical-intent treatment of metastatic spread from colorectal cancer-the first interim results from the OPTIMISE study

BACKGROUND

Patients with detectable ctDNA after radical-intent treatment of metastatic spread from colorectal cancer (mCRC) have a very high risk of recurrence, which may be prevented with intensified adjuvant chemotherapy (aCTh). In the OPTIMISE study, we investigate ctDNA-guided aCTh after radical-intent treatment of mCRC. Here we present results from the preplanned interim analysis.

MATERIAL AND METHODS

The study is an open-label 1:1 randomized clinical trial comparing ctDNA-guided aCTh against standard of care (SOC), with a run-in phase investigating feasibility measures. Key inclusion criteria; radical-intent treatment for mCRC and clinically eligible for triple-agent chemotherapy. Patients underwent a PET-CT scan before randomization. ctDNA analyses of plasma samples were done by ddPCR, detecting CRC-specific mutations and methylation of the NPY gene. In the ctDNA-guided arm, ctDNA positivity led to an escalation strategy with triple-agent chemotherapy, and conversely ctDNA negativity led to a de-escalation strategy by shared-decision making. Patients randomized to the standard arm were treated according to SOC. Feasibility measures for the run-in phase were; the inclusion of 30 patients over 12 months in two Danish hospitals, compliance with randomization >80%, rate of PET-CT-positive findings <20%, and eligibility for triple-agent chemotherapy >80%.

RESULTS

Thirty-two patients were included. The rate of PET-CT-positive cases was 22% (n = 7/32). Ninety-seven percent of the patients were randomized. Fourteen patients were randomly assigned to SOC and sixteen to ctDNA-guided adjuvant treatment and follow-up. All analyses of baseline plasma samples in the ctDNA-guided arm passed the quality control, and 19% were ctDNA positive. The median time to result was three working days. All ctDNA-positive patients were eligible for triple-agent chemotherapy.

CONCLUSION

The study was proven to be feasible and continues in the planned large-scale phase II trial. Results from the OPTIMISE study will potentially optimize the adjuvant treatment of patients undergoing radical-intent treatment of mCRC, thereby improving survival and reducing chemotherapy-related toxicity.