Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with metastatic colorectal cancer

Targeted Therapy and Immunotherapy in Elderly Patients with Metastatic Colorectal Cancer

OPINION STATEMENT

At initial diagnosis, over half of the patients with metastatic colorectal cancer (mCRC) are aged 65 years or older. In this population, age-related declines in organ reserve and the presence of comorbidities can significantly weaken drug tolerance and affect treatment outcomes. However, existing clinical guidelines, largely based on clinical trials involving younger, fitter adults, may not be fully applicable to older patients, particularly those are vulnerable. Moreover, chronologic age and commonly used performance assessment tools, such as the Eastern Cooperative Oncology Group and Karnofsky Performance Status scores, are insufficient for accurate evaluation of physiological fitness in older adults. To provide evidence-based references for clinicians, this review summarizes advances in targeted therapy and immunotherapy for elderly patients with mCRC over the past five years, with a focus on vascular endothelial growth factor (VEGF) targeting agents, epidermal growth factor receptor (EGFR) inhibitors, multi-targeted tyrosine kinase inhibitors (TKIs) and single-agent immunotherapy. Overall, for elderly patients assessed as fit, first-line treatment may include dose-reduced doublet chemotherapy combined with VEGF targeting agents, or alternatively, single-agent chemotherapy plus VEGF targeting agents. For vulnerable elderly patients with mCRC, single-agent chemotherapy with VEGF targeting agents remains the preferred first-line strategy, while RAS wild-type left-sided tumors may benefit from single-agent chemotherapy plus EGFR inhibitors. Although multi-targeted TKIs have shown positive outcomes in elderly patients who are intolerant to other therapies. There is currently no evidence supporting their use in first-line treatment or combination therapy. In terms of immunotherapy, similar to the general mCRC population, single-agent immunotherapy is recommended as a first-line option for elderly microsatellite instability-high/mismatch repair-deficient patients. Notably, integrating comprehensive geriatric assessment into clinical practice can facilitate personalized treatment strategies, particularly for vulnerable and frail patients.

Personalized prognostic model for colorectal cancer in the era of precision medicine: a dynamic approach based on real-world data

BACKGROUND

Predicting individual prognosis is required for patients with colorectal cancer in the era of precision medicine. However, this may be challenging for the conventional survival analysis such as the Cox proportional hazards model. This study aims to develop a personalized prognostic prediction that incorporates longitudinal data to improve predictions for colorectal cancer patients.

METHODS

Patients with advanced or recurrent colorectal cancer, who received treatment at Kyoto University Hospital between April 2015 and December 2021, were retrospectively analyzed. The Joint model is one of the dynamic prediction models. Using longitudinal clinical data, a carcinoembryonic antigen (CEA) prediction equation was developed for each patient. Additionally, a personalized prognostic prediction model was created using the Joint model. The prediction accuracy of the Joint model was compared with one of the Cox proportional hazards model.

RESULTS

Among the 1010 patients, 614 patients were enrolled. The median frequency of tumor marker measurement (per patient) was 20 times (range: 3-117 times). CEA values could be predicted accurately and the Pearson's correlation coefficient between measured CEA and predicted CEA was 0.931. In the Joint model, the significant prognostic factors were baseline age (HR, 1.039; 95% CI, 1.025-1.054), poor-differentiated tumor (HR, 2.600; 95% CI 1.446-4.675) and log2 (predicted CEA) (HR, 1.551; 95% CI 1.488-1.617). The areas under the curve at 2, 3, 4, and 5 were significantly higher for the Joint model than for the Cox proportional hazards model, respectively.

CONCLUSION

The Joint model may accurately predict personalized prognosis that reflects changes in longitudinal tumor marker values.

Hereditary Colorectal Cancer: Clinical Implications of Genomic Medicine and Precision Oncology

Approximately 10% of colorectal cancer (CRC) cases occur in the context of hereditary cancer-predisposing conditions caused by germline pathogenic variants (PVs) in cancer predisposition genes, with Lynch syndrome and familial adenomatous polyposis at the top of the list. Although the identification of hereditary CRC has traditionally relied on clinical characteristics, including familial accumulation, multiple and early onset of CRC and other related cancers, and the presence of gastrointestinal polyposis, more comprehensive approaches, such as universal tumor screening and universal germline testing, have recently been employed. From a technical standpoint, next-generation sequencing has enabled genome-wide analysis of genetic alterations in germline and somatic settings. Taking advantage of this technology, germline multigene panel testing has been utilized in genetic testing, which leads to the identification of PVs, not only in well-known hereditary CRC genes but also in rare causal genes, moderate-risk genes, and high-risk genes previously not linked to CRC predisposition. In addition, comprehensive genomic profiling and companion diagnostics for solid tumors occasionally yield unexpected hereditary CRC diagnoses. Thus, more hereditary CRCs have been identified not based on clinical phenotypes but rather by comprehensive approaches or as secondary findings of treatment drug testing. In this review, we discuss the impact of recent advances in genomic medicine on the clinical aspects of hereditary CRC, which has promoted an understanding of the entire landscape of genetic predisposition to CRC.

Surgical Resection Versus Microwave Ablation for Colorectal Liver Oligometastases: A Multicenter Cohort Study of 1027 Patients

BACKGROUND

The choice between surgical resection (SR) and microwave ablation (MWA) as first-line treatments that prolong survival duration for colorectal liver oligometastases (CRLOM) remains controversial.

OBJECTIVE

This study aimed to compare survival outcomes, therapeutic parameters, and safety between SR and MWA in patients with CRLOM.

METHODS

From January 2012 to December 2022, we identified 1027 eligible patients with CRLOM who underwent either SR (n = 464) or MWA (n = 563) as hepatic local-region treatment. The cumulative 1-, 3-, 5-, and 8-year overall survival (OS) and progression-free survival (PFS) rates between the two modalities were compared using the Kaplan-Meier method with the log-rank test. The propensity score matching (PSM) method was used to improve the selective bias. Univariate and multivariate analyses of clinicopathological variables were conducted to identify risk factors affecting long-term survival.

RESULTS

After PSM, all baseline variables were balanced between the SR (n = 393) and MWA groups (n = 393). After a median follow-up of 39.8 months, no significant differences in the long-term survival outcomes were observed between the two groups (median OS time, MWA: 70.6 months vs. SR: 83.2 months; P = 0.124; median PFS time, MWA: 18.5 months vs. SR: 22.3 months; P = 0.680). PSM-adjusted analyses revealed similar results. The presence of 3-5 intrahepatic nodules (hazards ratio [HR] 1.65; 95% CI 1.31-2.06; P < 0.001) and SR (HR 1.28; 95% CI 1.11-1.69; P = 0.028) were independent prognostic risk factors for OS. A significant interaction effect of therapeutic modality and age, pathological differentiation, diameter, and number was observed (P = 0.039, 0.004, 0.031, and 0.032).

CONCLUSIONS

MWA offers comparable long-term survival benefits to SR for patients with CRLOM.

Short-term outcomes of KangDuo surgical robot- versus Da Vinci surgical robot-assisted radical resection of colorectal cancer: a prospective cohort study

BACKGROUND AND PURPOSE

The KangDuo Surgical Robot-01 (KD-SR-01) system is a recently introduced robot-assisted endoscopic surgical device originally designed in China. The purpose of this prospective cohort study was to ascertain whether the KD-SR-01 system was substantially equivalent to a comparable robotic device in terms of safety, efficacy and treatment costs during colorectal cancer resection, and evaluate the learning curve of KangDuo robotic surgery.

METHOD

From October 2022 to May 2023, 50 patients (aged 18-80 years) with colorectal cancer were enrolled and randomly assigned to either the KangDuo group (KD-SR group; 26 patients) or the Da Vinci group (DV group; 24 patients). The primary endpoints were surgical success and conversion rates. In addition, cumulative summation (CUSUM) was used to plot the learning curve of KangDuo robot-assisted colorectal surgery and identify turning point (TP) case.

RESULTS

The two cohorts both successfully completed the procedure without any conversion to open or laparoscopic surgery. Time to first flatus and incidence of perioperative adverse events were equivalent between the KD-SR and DV groups. Additionally, no disparities were observed in pathological outcomes. Duration of operation and console time of the KD-SR group were significantly longer than those of the DV group. However, DV group had higher total hospitalization costs. With CUSUM analysis, TP for docking time, console time and duration of operation of KD-SR group were seen at the 11th case.

CONCLUSION

Considering the complexity of the procedure, KangDuo robot-assisted colorectal cancer surgery is safe and reproducible for the surgical management of colorectal cancer. In addition, 11 procedures seem to be the number required to reach the learning curve plateau in terms of operative time by the experienced surgeon.

TRIAL REGISTRATION

The study was registered at www.chictr.org.cn (Registration number: ChiCTR2200063172, Data of Registration: 2022-09-01).

Overall survival with frontline vs subsequent anti-epidermal growth factor receptor therapies in unresectable, RAS/BRAF wild-type, left-sided metastatic colorectal cancer

BACKGROUND

The combination of anti-epidermal growth factor receptor (EGFR) therapy and chemotherapy is currently a preferred first-line treatment for patients with unresectable, RAS and BRAF wild-type, left-sided metastatic colorectal cancer (mCRC). Several studies have also demonstrated the benefit of anti-EGFR therapy in subsequent line settings for this patient population. However, direct evidence comparing the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited, leaving a crucial gap in guiding optimal treatment strategies.

AIM

To compare overall survival (OS) between frontline and subsequent anti-EGFR treatment in patients with unresectable, RAS and BRAF wild-type, left-sided mCRC.

METHODS

We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital, Thailand, between January 2013 and April 2023. Patients were classified into two groups based on the sequence of their anti-EGFR treatment. The primary endpoint was OS.

RESULTS

Among 222 patients with a median follow-up of 29 months, no significant difference in OS was observed between the frontline and subsequent-line groups (HR 1.03, 95%CI: 0.73-1.46, P = 0.878). The median OS was 35.53 months (95%CI: 26.59-44.47) for the frontline group and 31.60 months (95%CI: 27.83-35.37) for the subsequent-line group. In the subsequent-line group, 71 patients (32.4%) who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months (95%CI: 12.87-26.53).

CONCLUSION

Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable, RAS/BRAF wild-type, left-sided mCRC patients, but early exposure is vital for those unlikely to receive subsequent therapy.

The Role of Chemotherapy in Patients with Synchronous Colorectal Liver Metastases: A Nationwide Study

BACKGROUND/OBJECTIVES

There is still no consensus as to whether patients with upfront resectable synchronous colorectal liver metastases (sCRLM) should receive neoadjuvant treatment prior to liver surgery. Two randomized controlled trials have assessed the role of peri-operative chemotherapy in sCRLM; neither have shown a survival benefit in the neoadjuvant group. The aim of this population-based study was to examine overall survival in patients treated with neoadjuvant chemotherapy and hepatectomy compared to patients who had upfront surgery.

METHODS

This is a retrospective observational study between 2009 and 2017 containing data extracted from two Swedish national registries. Descriptive statistics and Cox regression analyses were employed.

RESULTS

In total, 2072 patients with sCRLM were treated with liver surgery between 2009 and 2017. A majority (n = 1238, 60%) were treated with neoadjuvant chemotherapy, and 834 patients (40%) had upfront surgery. Patients in the upfront surgery group were older (median age 70 compared to 65 years, p ≤ 0.001). Median overall survival in the upfront surgery group was 26 months (95% CI 23-29 months) compared to 57 months (95% CI 42-48 months) in the neoadjuvant group, log rank p ≤ 0.001. In the multivariable Cox regression analysis, age ≥ 70 years (HR 1.46, 95% CI 1.25-1.70), T category of primary cancer (HR 1.41, 95% CI 1.09-1.84), lymphatic spread of primary cancer (HR 1.68, 95% CI 1.41-1.99), and number of liver metastases (six or more metastases resulted in HR 2.05, 95% CI 1.38-3.01) negatively influenced overall survival. By contrast, adjuvant therapy was protective (HR 0.80, 95% CI 0-69-0.94), whereas neoadjuvant treatment compared to upfront surgery did not influence overall survival (HR 1.04, 95% CI 0.86-1.26).

CONCLUSIONS

Neoadjuvant treatment in sCRLM did not confer a survival benefit compared to upfront surgery.

A novel nebulized drug delivery system based on an innovative high-pressure peristaltic pump availably applied to pressurized intraperitoneal aerosol chemotherapy

Background

Management of peritoneal carcinomatosis (PC) remains a significant clinical challenge due to a lack of effective therapies. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been identified as a safe and efficacious treatment for PC. However, despite the observed high potential for PIPAC in treating numerous PC cases, the technology is still limited in China. To address this deficit, we developed a novel nebulized drug delivery system (NDDS) and evaluated it in this study.

Methods

The NDDS was developed and was systematically assessed through tests of mechanical properties, granulometric analyses, sprayed distribution tests, and gravimetric analyses; moreover, drug penetration and distribution were examined in vitro and in a porcine model (female Tibetan pig).

Results

The NDDS, which included a high-pressure peristaltic pump, demonstrated a pressure initiation time of 5 s and a spray angle of 70°. Nebulization was consistent from the fifth second onward, with a median droplet diameter of 25.0-26.5 µm. The diameters of the sprayed intensive and expanded area were 26.1±1.4 and 48.5±1.0 cm at the vertical distance of 15 cm, and the stress generated was ≤3.790 Pa. Intraluminal drug distribution was extensive but heterogeneity, with 100- to 400-µm drug penetration depth (PD), and the optimal drug PD was observed in locations directly opposite to or adjacent surrounding the nozzle.

Conclusions

The developed NDDS demonstrated promising mechanical properties, effective granulometric characteristics, extensive spray coverage, and satisfactory drug penetration and distribution. It offers a practicable solution for the application of PIPAC and will hopefully improve the current dilemma in PC therapy.

Expert consensus on the optimal management of BRAFV600E-mutant metastatic colorectal cancer in the Asia-Pacific region

The burden of colorectal cancer (CRC) is high in the Asia-Pacific region, and several countries in this region have among the highest and/or fastest growing rates of CRC in the world. A significant proportion of patients will present with or develop metastatic CRC (mCRC), and BRAFV600E-mutant mCRC represents a particularly aggressive phenotype that is less responsive to standard chemotherapies. In light of recent therapeutic advances, an Asia-Pacific expert consensus panel was convened to develop evidence-based recommendations for the diagnosis, treatment, and management of patients with BRAFV600E-mutant mCRC. The expert panel comprised nine medical oncologists from Australia, Hong Kong, Singapore, and Taiwan (the authors), who met to review current literature and develop eight consensus statements that describe the optimal management of BRAFV600E-mutant mCRC in the Asia-Pacific region. As agreed by the expert panel, the consensus statements recommend molecular testing at diagnosis to guide individualized treatment decisions, propose optimal treatment pathways according to microsatellite stability status, advocate for more frequent monitoring of BRAFV600E-mutant mCRC, and discuss local treatment strategies for oligometastatic disease. Together, these expert consensus statements are intended to optimize treatment and improve outcomes for patients with BRAFV600E-mutant mCRC in the Asia-Pacific region.

Trifluridine/Tipiracil (FTD/TPI) in Metastatic Colorectal Cancer in Hong Kong: A Territory-Wide Cohort Study

INTRODUCTION

Randomized phase III trials showed that using trifluridine/tipiracil (FTD/TPI) in patients with pre-treated metastatic colorectal cancer (mCRC) conferred survival benefit versus placebo. Here, we investigated the effectiveness and safety of FTD/TPI and sought to identify prognostic factors among the mCRC population in Hong Kong.

METHODS

A non-interventional, retrospective, multicenter cohort study enrolled patients with mCRC who received FTD/TPI in seven public hospitals in Hong Kong between 2016 and 2020. Overall survival (OS) was the primary endpoint; treatment duration and occurrence of neutropenia were secondary endpoints. We also performed a post hoc analysis to identify factors influencing OS and treatment duration.

RESULTS

Overall, 456 patients were included (median age, 64.0 years; 57.5% men). Approximately half (225/456; 49.3%) had RAS wild-type tumors; the median treatment duration was 12.4 weeks (95% confidence interval [CI] 11.1-13.1). Median OS was 7.59 months (95% CI 7.00-8.21). Overall, 289 (63.4%) patients developed neutropenia of any grade and 159 (34.9%) developed grade ≥ 3 neutropenia. Neutropenia at 1 month occurred in 193 (43.1%) patients. The use of granulocyte colony-stimulating factor for neutropenia was reported for 42 (9.2%) patients. The development of neutropenia, absolute neutrophil count decrease of ≥ 2 grades in 1 month, absence of liver metastasis, and RAS wild-type status were associated with significantly longer OS and, except for RAS wild-type status (not analyzed), longer treatment duration (p < 0.05 for all comparisons).

CONCLUSION

Our data show that treatment with FTD/TPI offers survival benefits in patients with refractory mCRC in Hong Kong consistent with randomized controlled trials and other real-world studies. Furthermore, the prognosis in patients receiving FTD/TPI appears to be significantly better in those who develop neutropenia, with RAS wild-type status, or those without liver metastases, despite a higher rate of dose reduction in the real-world setting.

Late-line options for patients with metastatic colorectal cancer: a review and evidence-based algorithm

Over the past few years, several novel systemic treatments have emerged for patients with treatment-refractory metastatic colorectal cancer, thus making selection of the most effective later-line therapy a challenge for medical oncologists. Over the past decade, regorafenib and trifluridine-tipiracil were the only available drugs and often provided limited clinical benefit compared to best supportive care. Results from subsequent practice-changing trials opened several novel therapeutic avenues, both for unselected patients (such as trifluridine-tipiracil plus bevacizumab or fruquintinib) and for subgroups defined by the presence of actionable alterations in their tumours (such as HER2-targeted therapies or KRASG12C inhibitors) or with no acquired mechanisms of resistance to the previously received targeted agents in circulating tumour DNA (such as retreatment with anti-EGFR antibodies). In this Review, we provide a comprehensive overview of advances in the field over the past few years and offer a practical perspective on translation of the most relevant results into the daily management of patients with metastatic colorectal cancer using an evidence-based algorithm. Finally, we discuss some of the most appealing ongoing areas of research and highlight approaches with the potential to further expand the therapeutic armamentarium.

Unraveling the complexities of colorectal cancer and its promising therapies - An updated review

Colorectal cancer (CRC) continues to be a global health concern, necessitating further research into its complex biology and innovative treatment approaches. The etiology, pathogenesis, diagnosis, and treatment of colorectal cancer are summarized in this thorough review along with recent developments. The multifactorial nature of colorectal cancer is examined, including genetic predispositions, environmental factors, and lifestyle decisions. The focus is on deciphering the complex interactions between signaling pathways such as Wnt/β-catenin, MAPK, TGF-β as well as PI3K/AKT that participate in the onset, growth, and metastasis of CRC. There is a discussion of various diagnostic modalities that span from traditional colonoscopy to sophisticated molecular techniques like liquid biopsy and radiomics, emphasizing their functions in early identification, prognostication, and treatment stratification. The potential of artificial intelligence as well as machine learning algorithms in improving accuracy as well as efficiency in colorectal cancer diagnosis and management is also explored. Regarding therapy, the review provides a thorough overview of well-known treatments like radiation, chemotherapy, and surgery as well as delves into the newly-emerging areas of targeted therapies as well as immunotherapies. Immune checkpoint inhibitors as well as other molecularly targeted treatments, such as anti-epidermal growth factor receptor (anti-EGFR) as well as anti-vascular endothelial growth factor (anti-VEGF) monoclonal antibodies, show promise in improving the prognosis of colorectal cancer patients, in particular, those suffering from metastatic disease. This review focuses on giving readers a thorough understanding of colorectal cancer by considering its complexities, the present status of treatment, and potential future paths for therapeutic interventions. Through unraveling the intricate web of this disease, we can develop a more tailored and effective approach to treating CRC.

A multicenter, prospective, phase II trial of second-line aflibercept plus FOLFIRI in patients with metastatic colorectal cancer refractory to an anti-EGFR antibody: HGCSG1801

Aflibercept (AFL) plus FOLFIRI prolongs overall survival (OS) in patients with metastatic colorectal cancer (mCRC). However, there is limited evidence on the efficacy and safety of AFL plus FOLFIRI previously treated with anti-epidermal growth factor receptor (EGFR) agents. Therefore, we conducted a prospective open-label phase II trial evaluating the efficacy and safety of AFL plus FOLFIRI in Japanese patients with mCRC failing a prior oxaliplatin-based chemotherapy plus an anti-EGFR agent. AFL (4 mg/kg iv) followed by FOLFIRI (irinotecan 180 mg/m2, leucovorin 200 mg/m2 iv, bolus 5-fluorouracil [5-FU] 400 mg/m2, and infusional 5-FU 2400 mg/m2/46 h) was given every 2 weeks until progression or unacceptable toxicities. The primary endpoint was progression-free survival (PFS) rate at 6 months. Forty three patients were enrolled between November 2019 and October 2022. The primary endpoint was met: 6-month PFS rate was 58.8% (90% confidence interval [CI], 45.7%-72.0%). Median PFS and OS were 7.3 months (95% CI, 5.5-11.0 months) and 18.8 months (95% CI, 12.9-26.6 months), respectively. The overall response rate was 20.9% (95% CI, 10.0-36.0%) and disease control rate was 88.4% (95% CI, 74.9-96.1%). The main grade ≥3 adverse events included hypertension (62.8%), neutropenia (55.8%), leukopenia (25.6%), febrile neutropenia (11.6%), fatigue (9.3%), anorexia (9.3%), proteinuria (9.3%), and diarrhea (7.0%). No deaths and no new safety signals with a causal relation to the study treatment were observed. This study suggests that AFL plus FOLFIRI shows a high response rate and a manageable safety profile in Japanese patients with mCRC who failed prior oxaliplatin-based chemotherapy plus an anti-EGFR agent.

Continuing anti-EGFR monoclonal antibody after secondary resection significantly prolongs overall survival for patients with metastatic colorectal cancer who were responsive to first-line anti-EGFR monoclonal antibody plus chemotherapy doublet

The combination of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAb) and doublet chemotherapy is the standard first-line treatment for patients with wild-type RAS/BRAF metastatic colorectal cancer (mCRC). Some patients may require secondary resection after first-line treatment. However, it remains unclear whether targeted therapy should be continued after liver resection. To investigate whether targeted therapy can be spared after secondary resection, we retrospectively analyzed data from the Taiwan National Health Insurance Research Database for patients with wild-type KRAS mCRC who received first-line anti-EGFR mAb plus doublet chemotherapy. Between 2013 and 2018, 5694 mCRC patients were screened, with 174 meeting the eligibility criteria and being enrolled in this study. Among them, 153 patients continued anti-EGFR mAb after secondary resection. These patients demonstrated a significant improvement in overall survival (OS) but not in time to treatment failure. Postresection anti-EGFR mAb conferred OS benefits compared to no anti-EGFR mAb (43.17 vs. 31.41 months; P = 0.0064). When stratified by assessment period, OS was longer in patients assessed between 2016 and 2018 than in those assessed between 2012 and 2015 (not reached vs. 39.87 months; P = 0.1819). However, no significant difference was observed in time to treatment failure when stratified by assessment period or primary tumor location. A multivariate analysis revealed that postresection anti-EGFR mAb was an independent predictor of prolonged OS. In conclusion, for mCRC patients who have undergone secondary resection after first-line anti-EGFR mAb plus doublet chemotherapy, continuing anti-EGFR mAb may significantly extend OS, regardless of the primary tumor location.

Evidence-based clinical recommendations for hypofractionated radiotherapy: exploring efficacy and safety - Part 4: Liver and locally recurrent rectal cancer

In this paper, we review the use of hypofractionated radiotherapy for gastrointestinal malignancies, focusing on primary and metastatic liver cancer, and recurrent rectal cancer. Technological advancements in radiotherapy have facilitated the direct delivery of high-dose radiation to tumors, while limiting normal tissue exposure, supporting the use of hypofractionation. Hypofractionated radiotherapy is particularly effective for primary and metastatic liver cancer where high-dose irradiation is crucial to achieve effective local control. For recurrent rectal cancer, the use of stereotactic body radiotherapy offers a promising approach for re-irradiation, balancing efficacy and safety in patients who have been administered previous pelvic radiotherapy and in whom salvage surgery is not applicable. Nevertheless, the potential for radiation-induced liver disease and gastrointestinal complications presents challenges when applying hypofractionation to gastrointestinal organs. Given the lack of universal consensus on hypofractionation regimens and the dose constraints for primary and metastatic liver cancer, as well as for recurrent rectal cancer, this review aims to facilitate clinical decision-making by pointing to potential regimens and dose constraints, underpinned by a comprehensive review of existing clinical studies and guidelines.

Modified FOLFOXIRI plus cetuximab versus bevacizumab in RAS wild-type metastatic colorectal cancer: a randomized phase II DEEPER trial

The clinical significance of FOLFOXIRI (5-FU, leucovorin, oxaliplatin, and irinotecan) plus anti-EGFR monoclonal antibody using cetuximab for metastatic colorectal cancer (mCRC) remains controversial. We report results from a randomized phase 2 DEEPER trial (UMIN000018217, jRCTs061180022) to test the superiority of modified (m)-FOLFOXIRI plus weekly cetuximab over bevacizumab in patients with RAS wild-type (wt) mCRC. Primary endpoint was depth of response (DpR). Secondary endpoints included objective response rate (ORR), early tumor shrinkage (ETS) at week 8, progression-free survival (PFS), overall survival (OS), time to tumor growth (TTG), time to treatment failure (TTF), association between tumor shrinkage and prognosis, association between TTG and prognosis, R0 resection rate, and safety. In 359 enrolled patients with RAS wt mCRC, median DpR was significantly better in cetuximab (57.3% vs 46.0%, p = 0.0029); however, ORR, ETS, R0 resection rate, TTG, TTF, PFS and OS were similar between 2 treatments. There was a weak association between DpR and survival time in both treatments. The correlation between TTG and OS was slightly stronger in cetuximab. The post-hoc exploratory analysis showed that cetuximab produced greater PFS (15.3 vs 11.7 months; HR 0.68) and OS (53.6 vs 40.2 months; HR 0.54) in patients with left-sided and RAS/BRAF wt tumors. m-FOLFOXIRI plus cetuximab has clinical benefit for tumor shrinkage in RAS wt mCRC. The survival benefit for RAS/BRAF wt and left-sided mCRC needs further investigation.

Durable response to pembrolizumab in hepatic metastasis from colonic carcinoma with Lynch syndrome: a case report

Pembrolizumab and other immunotherapies have become central in treating metastatic colon cancer, particularly effective in patients with mismatch repair deficiencies. We report a case involving a man who initially underwent radical surgery for sigmoid colon cancer on April 27, 2011, followed by hepatic tumor resection on September 21, 2017. Post-surgery, he received eight cycles of adjuvant chemotherapy with the CAPEOX regimen and was regularly monitored through CT and MRI scans. On August 24, 2022, liver metastases were detected, and he was diagnosed with Lynch syndrome (LS) due to germline mutation in the MSH2 and EPCAM genes. He commenced treatment with 200mg of pembrolizumab intravenously every three weeks on September 2, 2022, and demonstrated a sustained response. However, after 17 cycles, he developed a treatment related adverse event (TRAE) of pancreatic endocrine dysfunction, leading to type 1 diabetes, managed with subcutaneous insulin injections. After 30 cycles of treatment, no evidence of disease was observed. This case underscores the significant clinical benefits of first-line pembrolizumab in managing hepatic metastasis in colonic carcinoma associated with LS, despite the occurrence of TRAEs. It raises critical questions regarding the optimal duration of immunotherapy following a complete or partial response and whether treatment should be discontinued upon the emergency of TRAEs. Continued research and forthcoming clinical trials with checkpoint inhibitors are expected to refine treatment protocols for LS-associated carcinoma.

An SNP Marker Predicts Colorectal Cancer Outcomes with 5-Fluorouracil-Based Adjuvant Chemotherapy Post-Resection

Colorectal cancer (CRC) is a global health concern, necessitating adjuvant chemotherapy post-curative surgery to mitigate recurrence and enhance survival, particularly in intermediate-stage patients. However, existing therapeutic disparities highlight the need for biomarker-guided adjuvant chemotherapy to achieve better CRC inhibition. This study explores the molecular mechanisms underlying the inhibition of CRC through a genome-wide association study (GWAS) focused on 5-fluorouracil (5-FU)-based adjuvant therapy in intermediate-stage CRC patients, a domain previously unexplored. We retrospectively included 226 intermediate-stage CRC patients undergoing surgical resection followed by 5-FU-based adjuvant chemotherapy. The exploration cohort comprised 31 patients, and the validation cohort included 195 individuals. Genotyping was carried out using either Axiom Genome-Wide TWB 2.0 Array Plate-based or polymerase chain reaction-based methods on genomic DNA derived from collected tissue samples. Statistical analyses involved descriptive statistics, Kaplan-Meier analyses, and Cox proportional hazard analyses. From the GWAS, potential genetic predictors, GALNT14-rs62139523 and DNMBP-rs10786578 genotypes, of 5-FU-based adjuvant therapy following surgery in intermediate-stage CRC patients were identified. Validation in a larger cohort of 195 patients emphasized the predictive significance of GALNT14-rs62139523 genotypes, especially the "A/G" genotype, for improved overall and progression-free survival. This predictive association remained robust across various subgroups, with exceptions for specific demographic and clinical parameters such as age < 58 years old, CEA ≤ 2.5 ng/mL, tumor diameter > 44.0 mm, and tumor-free margin ≥ 50 mm. This study identifies that the GALNT14-rs62139523 "A/G" genotype modulates therapeutic outcomes, establishing it as a promising biomarker for predicting favorable responses to 5-FU-based adjuvant chemotherapy in intermediate-stage CRC patients, although further investigations are needed to detail these mechanisms.

Plasma Angiogenic Factors as Predictors of the Efficacy of Second-line Chemotherapy Combined with Angiogenesis Inhibitors in Metastatic Colorectal Cancer: Results From the GI-SCREEN CRC-Ukit Study

BACKGROUND

The significance of angiogenic factors as predictors of second-line (2L) chemotherapy efficacy when combined with angiogenesis inhibitors for metastatic colorectal cancer (mCRC) remains unestablished.

PATIENTS AND METHODS

In this multicenter prospective observational study, 17 angiogenic factors were analyzed in plasma samples collected at pretreatment and progression stages using a Luminex multiplex assay. Patients who received chemotherapy plus bevacizumab (BEV group), FOLFIRI plus ramucirumab (RAM group), or FOLFIRI plus aflibercept (AFL group) as the 2L treatment were included. Interactions between pretreatment and treatment groups for progression-free survival (PFS), overall survival (OS), and response rate (RR) were assessed using the propensity-score weighted Cox proportional hazards model.

RESULTS

From February 2018 to September 2020, 283 patients were analyzed in the 2L cohort. A strong interaction was observed for PFS between BEV and RAM with HGF, sNeuropilin-1, sVEGFR-1, and sVEGFR-3. Interactions for RR between the BEV and RAM groups were observed for sNeuropilin-1 and sVEGFR-1. Contrarily, OS, PlGF, sVEGFR-1, and sVEGFR-3 differentiated the treatment effect between BEV and AFL. Plasma samples were evaluable for dynamic analysis in 203 patients. At progression, VEGF-A levels significantly decreased in the BEV group and increased in the RAM and AFL groups.

CONCLUSION

The pretreatment plasma sVEGFR-1 and sVEGFR-3 levels could be predictive biomarkers for distinguishing BEV and RAM when combined with chemotherapy in 2L mCRC treatment. Based on the VEGF-A dynamics at progression, selecting RAM or AFL for patients with significantly elevated VEGF-A levels may be a 2L treatment strategy, with BEV considered for the third-line treatment.

CLINICAL TRIAL NUMBER

UMIN000028616.

Temporal dynamics of RAS mutations in circulating tumor DNA in metastatic colorectal cancer: clinical significance of mutation loss during treatment

PURPOSE

In metastatic colorectal cancer (mCRC), RAS mutation loss may occur during the standard-of-care regimen. In this study, we aimed to investigate the temporal dynamics of the RAS gene and its clinical significance.

METHODS

This was a retrospective, single-center study that included 82 patients with tissue RAS-mutant (RAS-MT) mCRC who underwent circulating tumor DNA (ctDNA) RAS monitoring between January, 2013-April, 2023. Patients were analyzed for the rate of change over time to acquired RAS mutation loss (aRAS-ML) and clinicopathological factors. The prognostic relevance of mutation loss was assessed.

RESULTS

aRAS-ML was detected in 33 (40.2%) patients, 32 of whom had a mutation loss in the first ctDNA RAS assay. Patients with a RAS mutation detected in the first assay had a median time of 8 months until the second ctDNA RAS assay, with 4.5% cases newly converted to aRAS-ML; no new conversions were detected at the third assay. The aRAS-ML group exhibited more single-organ metastases in the target organ during ctDNA measurement (aRAS-ML: 84.8% vs. RAS-MT: 59.2%, p = 0.02). Of the 33 patients with aRAS-ML, seven (21.2%) received anti-epidermal growth factor receptor (EGFR) therapy, with a median progression-free survival of 8 months. Multivariate analysis revealed that persistent ctDNA RAS mutation was an independent prognostic factor for overall survival (hazard ratio: 2.7, 95% confidence interval: 1.1-6.3, p = 0.02).

CONCLUSION

The rate of ctDNA mutation loss in patients with RAS-MT mCRC decreases over time. Therefore, using a ctDNA RAS assay early in treatment will assist in challenging the use of EGFR regimens.

Monitoring ctDNA RAS Mutational Status in Metastatic Colorectal Cancer: A Trial Protocol of RAS-trace and RAS-trace-2 Studies

Background

Spatial and temporal heterogeneities of RAS and other molecular genes should be considered in the treatment of metastatic colorectal cancer (mCRC) treated with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs); acquired RAS mutation is sometimes observed at disease progression of treatment with the anti-EGFR mAb. At the same time, discrepancy of RAS status from tissues and circulating tumor DNA (ctDNA) in the same patient is sometimes observed. Based on this, we commenced two observational studies to clarify these heterogeneities of RAS and BRAF in mCRC, using next generation sequencing from liquid biopsy.

Methods/Design

RAS-trace study is an observational study to monitor ctDNA RAS/BRAF/PIK3CA status every 4-12 weeks using the Plasma-SeqSensei™ CRC RUO Kit (Sysmex Inostics GmbH) in mCRC with RAS/BRAF wild-type (wt) on tumor tissue. The primary endpoint was the time to the acquired RAS mutations. A total of 42 patients has been accrued. RAS-trace-2 study is also an observational study aimed at comparing the efficacy of the anti-EGFR mAb in ctDNA RAS/BRAF wt with ctDNA RAS or BRAF mutant mCRC patients, whose RAS/BRAF are wt in tumor tissue. The primary endpoint was progression-free survival in patients with ctDNA RAS/BRAF wt and RAS or BRAF mutant. A total of 240 patients will be accrued over 2 years.

Discussion

These trials will help us understanding the clinical significance of spatial and temporal heterogeneities of RAS, BRAF and other genes, while optimizing the anti-EGFR mAb treatment strategies in mCRC.

Drug-eluting beads transcatheter arterial chemoembolization combined with systemic therapy versus systemic therapy alone as first-line treatment for unresectable colorectal liver metastases

Purpose

The purpose of this retrospective study was to compare the therapeutic efficacy and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE) combined with systemic therapy to systemic therapy alone as first-line treatment for unresectable patients with colorectal liver metastases (CRLM).

Methods

From December 2017 to December 2022, patients with unresectable CRLM who received systemic therapy with or without DEB-TACE as first-line treatment were included in the study. The primary endpoint was progression-free survival (PFS). Secondary endpoints were tumor response, conversion rate and adverse events.

Results

Ninety-eight patients were enrolled in this study, including 46 patients who received systemic therapy combined with DEB-TACE (DEB-TACE group) and 52 patients who received systemic therapy alone (control group). The median PFS was elevated in the DEB-TACE group compared with the control group (12.1 months vs 8.4 months, p = 0.008). The disease control rate was increased in the DEB-TACE group compared with the control group (87.0% vs 67.3%, p = 0.022). Overall response rates (39.1% vs 25.0%; p = 0.133) and conversion rate to liver resection (33.8% vs 25.0%; p = 0.290) were no different between the two groups. The multivariate analysis showed that treatment options, size of liver metastasis, number of liver metastasis, synchronous metastases, and extrahepatic metastases were independent prognostic factor of PFS. Further subgroup analyses illustrated that PFS was beneficial with the DEB-TACE group in patients with age ≥ 60, male, left colon, synchronous metastases, bilobar, number of liver metastasis > 5, extrahepatic metastases, non-extrahepatic metastases, CEA level < 5 (ng/ml), and KRAS wild-type. No grade 4 or 5 toxicities related to DEB-TACE procedures were observed.

Conclusion

In patients with unresectable CRLM, systemic chemotherapy with DEB-TACE as first-line treatment may improve progression-free survival and disease control rate outcomes over systemic chemotherapy alone with manageable safety profile.

Baseline ctDNA gene alterations as a biomarker of survival after panitumumab and chemotherapy in metastatic colorectal cancer

Certain genetic alterations and right-sided primary tumor location are associated with resistance to anti-epidermal growth factor (EGFR) treatment in metastatic colorectal cancer (mCRC). The phase 3 PARADIGM trial (n = 802) demonstrated longer overall survival with first-line anti-EGFR (panitumumab) versus antivascular endothelial growth factor (bevacizumab) plus modified FOLFOX6 in patients with RAS wild-type mCRC with left-sided primary tumors. This prespecified exploratory biomarker analysis of PARADIGM (n = 733) evaluated the association between circulating tumor DNA (ctDNA) gene alterations and efficacy outcomes, focusing on a broad panel of gene alterations associated with resistance to EGFR inhibition, including KRAS, NRAS, PTEN and extracellular domain EGFR mutations, HER2 and MET amplifications, and ALK, RET and NTRK1 fusions. Overall survival was prolonged with panitumumab plus modified FOLFOX6 versus bevacizumab plus modified FOLFOX6 in patients with ctDNA that lacked gene alterations in the panel (that is, negative hyperselected; median in the overall population: 40.7 versus 34.4 months; hazard ratio, 0.76; 95% confidence interval, 0.62-0.92) but was similar or inferior with panitumumab in patients with ctDNA that contained any gene alteration in the panel (19.2 versus 22.2 months; hazard ratio, 1.13; 95% confidence interval, 0.83-1.53), regardless of tumor sidedness. Negative hyperselection using ctDNA may guide optimal treatment selection in patients with mCRC. ClinicalTrials.gov registrations: NCT02394834 and NCT02394795 .

Impact of KRASG12 mutations on survival with trifluridine/tipiracil plus bevacizumab in patients with refractory metastatic colorectal cancer: post hoc analysis of the phase III SUNLIGHT trial

BACKGROUND

In metastatic colorectal cancer (mCRC), KRAS mutations are often associated with poorer survival; however, the prognostic impact of specific point mutations is unclear. In the phase III SUNLIGHT trial, trifluridine/tipiracil (FTD/TPI) plus bevacizumab significantly improved overall survival (OS) versus FTD/TPI alone. We assessed the impact of KRASG12 mutational status on OS in SUNLIGHT.

PATIENTS AND METHODS

In the global, open-label, randomized, phase III SUNLIGHT trial, adults with mCRC who had received no more than two prior chemotherapy regimens were randomized 1 : 1 to receive FTD/TPI alone or FTD/TPI plus bevacizumab. In this post hoc analysis, OS was assessed according to the presence or absence of a KRASG12 mutation in the overall population and in patients with RAS-mutated tumors.

RESULTS

Overall, 450 patients were analyzed, including 302 patients in the RAS mutation subgroup (214 with a KRASG12 mutation and 88 with a non-KRASG12RAS mutation). In the overall population, similar OS outcomes were observed in patients with and without a KRASG12 mutation [median 8.3 and 9.2 months, respectively; hazard ratio (HR) 1.09, 95% confidence interval (CI) 0.87-1.4]. Similar OS outcomes were also observed in the subgroup analysis of patients with a KRASG12 mutation versus those with a non-KRASG12RAS mutation (HR 1.03, 95% CI 0.76-1.4). FTD/TPI plus bevacizumab improved OS compared with FTD/TPI alone irrespective of KRASG12 mutational status. Among patients with a KRASG12 mutation, the median OS was 9.4 months with FTD/TPI plus bevacizumab versus 7.2 months with FTD/TPI alone (HR 0.67, 95% CI 0.48-0.93), and in patients without a KRASG12 mutation, the median OS was 11.3 versus 7.1 months, respectively (HR 0.59, 95% CI 0.43-0.81).

CONCLUSIONS

The presence of a KRASG12 mutation had no detrimental effect on OS among patients treated in SUNLIGHT. The benefit of FTD/TPI plus bevacizumab over FTD/TPI alone was confirmed independently of KRASG12 status.

Optimizing Treatment Strategy for Oligometastases/Oligo-Recurrence of Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer, and nearly half of CRC patients experience metastases. Oligometastatic CRC represents a distinct clinical state characterized by limited metastatic involvement, demonstrating a less aggressive nature and potentially improved survival with multidisciplinary treatment. However, the varied clinical scenarios giving rise to oligometastases necessitate a precise definition, considering primary tumor status and oncological factors, to optimize treatment strategies. This review delineates the concepts of oligometastatic CRC, encompassing oligo-recurrence, where the primary tumor is under control, resulting in a more favorable prognosis. A comprehensive examination of multidisciplinary treatment with local treatments and systemic therapy is provided. The overarching objective in managing oligometastatic CRC is the complete eradication of metastases, offering prospects of a cure. Essential to this management approach are local treatments, with surgical resection serving as the standard of care. Percutaneous ablation and stereotactic body radiotherapy present less invasive alternatives for lesions unsuitable for surgery, demonstrating efficacy in select cases. Perioperative systemic therapy, aiming to control micrometastatic disease and enhance local treatment effectiveness, has shown improvements in progression-free survival through clinical trials. However, the extension of overall survival remains variable. The review emphasizes the need for further prospective trials to establish a cohesive definition and an optimized treatment strategy for oligometastatic CRC.

Management of brain metastasis from rectal cancer using whole‑brain radiation therapy followed by bevacizumab and chemotherapy: A case report

Brain metastases in colorectal cancer are uncommon, which has resulted in a shortage of data concerning their screening and management. Multiple therapeutic modalities with chemotherapy, chemoradiation and targeted therapy, including bevacizumab and cetuximab regimens, have shown promising results. The present study describes the case of a 47-year-old male, diagnosed with T4N2M1 rectal cancer who underwent systemic therapy with modified FOLFOXIRI and cetuximab. The patient achieved a complete clinical response after 12 cycles. Following the discontinuation of cetuximab, the patient was given capecitabine as a maintenance therapy and subsequently developed brain metastasis. The patient received whole-brain radiation therapy (WBRT) followed by a bevacizumab plus FOLFIRI regimen. The patient showed a good response as revealed by cranial magnetic resonance imaging, with a reduction in lesion size and no sign of cerebral edema. In addition, the patient maintained a stable neurological condition for >10 months. These findings suggest that the early detection of brain metastases requires the close monitoring of neurological symptoms. In addition, WBRT followed by bevacizumab and chemotherapy is a potential management plan for brain metastasis from rectal cancer.

Real-World Study to Assess Patterns of Treatment Practices and Clinical Outcomes in Metastatic Colorectal Cancer Patients with RAS Wild-Type Left-Sided Tumours in Canada

Minimal Canadian data are available on the RAS testing rates, treatment patterns, and corresponding overall survival (OS) in metastatic colorectal cancer (mCRC) patients. We conducted a population-based cohort study of left-sided RAS wild-type (WT) mCRC patients diagnosed between 1 January 2014 and 31 December 2019, and who were treated with first-line (1L) chemotherapy plus the epidermal growth factor receptor inhibitor panitumumab, chemotherapy plus bevacizumab, or chemotherapy alone, in Alberta, Canada, using electronic medical records and administrative health system data. Of the 2721 patients identified with left-sided mCRC, 320 patients with RAS WT mCRC were treated with 1L systemic therapy: chemotherapy plus panitumumab (n = 64), chemotherapy plus bevacizumab (n = 52), or chemotherapy alone (n = 204). Only 65% and 39% of the 320 1L-treated patients initiated second- and third-line therapy, respectively. A total of 71% of individuals with treated left-sided mCRC underwent RAS testing. The median OS for mCRC patients with RAS WT left-sided tumours was higher for patients treated with 1L panitumumab plus chemotherapy (34.3 months; 95% CI: 23.8-39.6) than for patients who received 1L chemotherapy alone (30.0 months; 95% CI: 24.9-34.1) or 1L bevacizumab plus chemotherapy (25.6 months; 95% CI: 21.2-35.7). These findings highlight an unmet need in left-sided RAS WT mCRC, with relatively few individuals receiving a biologic agent in combination with chemotherapy in the 1L setting, a high rate of attrition between lines, and a need for increased RAS testing before treatment initiation.

Real-world evidence of trifluridine/tipiracil plus bevacizumab in metastatic colorectal cancer using an administrative claims database in Japan

BACKGROUND

Trifluridine/tipiracil (FTD/TPI) and regorafenib (REG) are standard therapies for refractory metastatic colorectal cancer (mCRC). No results of large real-world data directly comparing FTD/TPI + bevacizumab (BEV) with FTD/TPI or REG monotherapy have been reported. We evaluated the efficacy and safety of FTD/TPI + BEV in a real-world setting.

MATERIALS AND METHODS

This retrospective study used a Japanese claims database provided by Medical Data Vision Co., Ltd. (Tokyo, Japan). Eligible patients were aged 20 years and over with a diagnosis of mCRC, and received their first dose of FTD/TPI or REG from 2014 to 2021. The primary endpoint was overall survival (OS) in a propensity score matching (PSM) population in which PSM was carried out by matching using a 1 : 1 ratio for the FTD/TPI + BEV group and the control group (FTD/TPI or REG) by propensity score. To enhance robustness, sensitivity analyses of OS were carried out using the inverse probability treatment weighted (IPTW) approach and the analysis in the all eligible population. Secondary endpoints included time to treatment discontinuation (TTD), incidence of adverse events, and post-treatment.

RESULTS

Eligible population was 2369 for the FTD/TPI + BEV group and 9318 for the control group. The PSM population was 1787 for each group. Median OS (mOS) was longer in the FTD/TPI + BEV group compared to the control group [17.0 versus 11.6 months, hazard ratio (HR) = 0.70, P < 0.001] in the PSM population. Similarly, mOS was longer for the FTD/TPI + BEV group compared to that for the control group in IPTW analyses and in the all eligible population (both HRs = 0.68). Median TTD was 3.3 months for the FTD/TPI + BEV group and 1.8 months for the control group in the PSM population (P < 0.001).

CONCLUSIONS

Real-world data showed that FTD/TPI + BEV was significantly associated with OS and TTD compared to FTD/TPI or REG. In clinical practice, FTD/TPI + BEV can be a favorable regimen for refractory mCRC.