Microsatellite stable metastatic colorectal cancer without liver metastasis may be preferred population for regorafenib or fruquintinib plus sintilimab as third-line or above therapy:A real-world study

Inflammation and Immunity in Liver Neoplasms: Implications for Future Therapeutic Strategies

Over the past two decades, the "hallmarks of cancer" have revolutionized cancer research and highlighted the crucial roles of inflammation and immunity. Protumorigenic inflammation promotes cancer development along with inhibition of antitumor immunity, shaping the tumor microenvironment (TME) toward a tumor-permissive state and further enhancing the malignant potential of cancer cells. This immunosuppressive TME allows tumors to evade immunosurveillance. Thus, understanding the complex interplay between tumors and the immune system within the TME has become pivotal, especially with the advent of immunotherapy. Although immunotherapy has achieved notable success in many malignancies, primary liver cancer, particularly hepatocellular carcinoma, presents unique challenges. The hepatic immunosuppressive environment poses obstacles to the effectiveness of immunotherapy, along with high mortality rates and limited treatment options for patients with liver cancer. In this review, we discuss current understanding of the complex immune-mediated mechanisms underlying liver neoplasms, focusing on hepatocellular carcinoma and liver metastases. We describe the molecular and cellular heterogeneity within the TME, highlighting how this presents unique challenges and opportunities for immunotherapy in liver cancers. By unraveling the immune landscape of liver neoplasms, this review aims to contribute to the development of more effective therapeutic interventions, ultimately improving clinical outcomes for patients with liver cancer.

Fruquintinib Combined With PD-1 Inhibitors for the Treatment of the Patients With Microsatellite Stability Metastatic Colorectal Cancer: Real-World Data

AIMS

Programmed death-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitors have shown limited effectiveness in patients with microsatellite stable (MSS) metastatic colorectal cancer (mCRC). Combining anti-angiogenesis inhibitors with PD-1 inhibitors has the potential to reverse the immunosuppressive tumour microenvironment, synergistically enhancing the anti-tumour immune response in MSS mCRC. The goal is to present real-world data that prove the clinical efficacy and safety of fruquintinib combined with PD-1 inhibitors in MSS mCRC.

MATERIALS AND METHODS

We conducted a real-world retrospective study in patients with MSS mCRC who received treatment with fruquintinib combined with PD-1 inhibitors between May 2019 and March 2023 in our centre.

RESULTS

Seventy seven patients with MSS mCRC received fruquintinib combined with PD-1 inhibitors. In total, 5.2% of patients (4/77) achieved a partial response (PR), while 50.6% (39/77) had a stable disease (SD). Notably, three lesions achieving PR were all lung metastases and the overall disease control rate (DCR) reached 55.8% (43/77). Median progression-free survival (PFS) and overall survival (OS) reached 5.1 months (95% CI: 3.6-6.7) and 14.6 months (95% CI: 9.6-15.6), respectively. Multivariate Cox analysis showed that prior treatment without vascular endothelial growth factor (VEGF) inhibitors was significantly associated with PFS and OS (p < 0.05). Further analysis indicated that total- or polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) significantly decreased after treatment (P = 0.039), especially in the PR/SD group (P = 0.003). Most adverse events included abdominal pain, rash, oedema, diarrhoea, and immunotherapy-associated hypothyroidism, yet symptoms were controllable.

CONCLUSION

Our results provided additional evidence that patients with MSS mCRC could benefit from the combination of fruquintinib and PD-1 inhibitors, especially those with lung metastases or without prior treatment with VEGF inhibitors. The detection of MDSCs may be an immune indicator for predicting of the combined therapy.

Efficacy of Combined PD-1 Inhibitor and Bevacizumab in Unresectable Liver Metastasis of MSI-H Colorectal Cancer: A Case Report

BACKGROUND Programmed death 1 (PD-1) inhibitors have demonstrated limited effectiveness in patients with microsatellite instability-high (MSI-H) colorectal cancer (CRC). Recent studies suggest that their efficacy can be enhanced when combined with anti-angiogenic agents. CASE REPORT We present a case of a 25-year-old woman with CRC harboring a KRAS mutation and MSI-H status, along with initially unresectable liver metastases. Despite receiving first-line chemotherapy combined with bevacizumab, her disease progressed. Subsequently, she was treated with a combination of a PD-1 inhibitor and bevacizumab as second-line therapy. This approach resulted in a partial response, ultimately leading to a pathological complete response after resection of the liver metastases. The patient continued with the combination therapy for over a year and showed no serious treatment-related adverse events. Postoperative follow-up imaging confirmed the absence of tumor recurrence or metastasis, and the patient remained in remission. CONCLUSIONS This case highlights the potential of combining immune checkpoint inhibitors with anti-angiogenic agents in treating patients with MSI-H metastatic CRC, particularly those with initially unresectable liver metastases. Although further research is warranted to validate this therapeutic strategy, our findings support the use of this combination as a viable option for achieving pathological complete response and improving outcomes in this patient population. Comprehensive clinical studies are needed to optimize conversion therapy regimens and enhance the likelihood of success in treating patients with MSI-H CRC with advanced disease.

Synergistic Effects of Fruquintinib Combined with Immune Checkpoint Inhibitors on Metastatic Colorectal Cancer

BACKGROUND

Fruquintinib has received approval for the management of patients with chemotherapy-resistant metastatic colorectal cancer (mCRC). However, combination of fruquintinib with immune checkpoint inhibitors (ICIs) is yet to be extensively studied. This study aims to assess the clinical efficacy, safety, and prognostic indicators of treatment regimen combining fruquintinib with ICIs in mCRC patients.

METHODS

We analyzed data from mCRC patients who were administered fruquintinib either as a monotherapy or in conjunction with ICIs following conventional chemotherapy. Parameters such as the objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and incidence of adverse events were meticulously evaluated. Furthermore, the relationship between blood markers and patient prognosis was examined.

RESULTS

A total of 72 mCRC patients were included in this study, with a median observation period of 48 months, 19 were treated with fruquintinib alone, while 53 received a combination therapy involving fruquintinib and ICIs. The combined therapy group exhibited superior ORR and DCR compared to the fruquintinib monotherapy group. Additionally, significant improvements in OS and PFS were observed in the combined treatment group. The occurrence of adverse events was generally manageable and well-tolerated across both groups, with no significant difference in incidence rates. Notably, albumin levels were identified as a prognostic marker for PFS and OS in the univariate Cox regression analysis.

CONCLUSIONS

The combination of fruquintinib with ICIs demonstrated enhanced clinical efficacy and improved survival outcomes compared to fruquintinib monotherapy in mCRC patients. The safety of the combination regimen was deemed manageable and acceptable.

Fruquintinib in refractory metastatic colorectal cancer: a multicenter real-world study

BACKGROUND

Fruquintinib has been approved by the Food and Drug Administration for refractory metastatic colorectal cancer (mCRC). In clinical practice, fruquintinib is sometimes used in combination with other drugs, but its efficacy and safety are still unknown. In this study, we present a comprehensive analysis of the real-world treatment modalities involving fruquintinib in late-line settings for mCRC across six centers in China.

PATIENTS AND METHODS

Patients with refractory mCRC who received fruquintinib treatment in six centers in China between 1 January 2021 and 31 June 2022 were included in this study. Patients were categorized into two cohorts: the monotherapy group (treated solely with fruquintinib) and the combined group (received fruquintinib combined with chemotherapy and/or anti-programmed cell death protein 1 antibodies). Demographic, clinical, survival, and safety data were retrospectively analyzed. The study was registered at clinicaltrials.gov as NCT06202417.

RESULTS

A total of 520 patients were included in this study. The median follow-up time was 9.7 months. The disease control rate was 64.8%. The median progression-free survival was 5.0 months and the median overall survival was 11.4 months. Of them, 387 (74.4%) were treated with fruquintinib alone, while 133 (25.6%) were administered fruquintinib plus chemotherapy and/or anti-programmed cell death protein 1 antibodies, respectively. Adverse events were reported by 91.3% (457/520) of patients. The rate of grade 3 or 4 toxicity was 42.4% (237/520). No treatment-related death occurred.

CONCLUSION

Fruquintinib, either as a standalone treatment or in combination with other medications, demonstrates substantial efficacy and favorable tolerability in refractory mCRC patients.

Biomarkers to predict efficacy of immune checkpoint inhibitors in colorectal cancer patients: a systematic review and meta-analysis

Immune checkpoint inhibitors (ICIs) are approved to treat colorectal cancer (CRC) with mismatch-repair gene deficiency, but the response rate remains low. Value of current biomarkers to predict CRC patients' response to ICIs is unclear due to heterogeneous study designs and small sample sizes. Here, we aim to assess and quantify the magnitude of multiple biomarkers for predicting the efficacy of ICIs in CRC patients. We systematically searched MEDLINE, Embase, the Cochrane Library, and Web of Science databases (to June 2023) for clinical studies examining biomarkers for efficacy of ICIs in CRC patients. Random-effect models were performed for meta-analysis. We pooled odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) for biomarkers predicting response rate and survival. 36 studies with 1867 patients were included in systematic review. We found that a lower pre-treatment blood neutrophil-to-lymphocyte ratio (n=4, HR 0.37, 95%CI 0.21-0.67) predicts good prognosis, higher tumor mutation burden (n=10, OR 4.83, 95%CI 2.16-10.78) predicts response to ICIs, and liver metastasis (n=16, OR 0.32, 95%CI 0.16-0.63) indicates resistance to ICIs, especially when combined with VEGFR inhibitors. But the predictive value of tumor PD-L1 expression (n=9, OR 1.01, 95%CI 0.48-2.14) was insignificant in CRC. Blood neutrophil-to-lymphocyte ratio, tumor mutation burden, and liver metastasis, but not tumor PD-L1 expression, function as significant biomarkers to predict efficacy of ICIs in CRC patients. These findings help stratify CRC patients suitable for ICI treatments, improving efficacy of immunotherapy through precise patient management. (PROSPERO, CRD42022346716).

Efficacy, safety, and predictors of fruquintinib plus anti-programmed death receptor-1 (PD-1) antibody in refractory microsatellite stable metastatic colorectal cancer in a real-world setting: a retrospective cohort study

BACKGROUND

Patients with microsatellite stable (MSS) advanced colorectal cancer (CRC) have few alternatives for salvage therapy and a large unmet clinical need. Preclinical studies demonstrate that fruquintinib combined with anti-programmed death protein 1 (PD-1) has a synergistic anti-tumor effect. But a few phase 2 clinical studies show inconsistent efficacy of this combination therapy in CRC. The aim of this study was to investigate the efficacy, safety, and predictors of fruquintinib plus PD-1 antibodies in refractory MSS metastatic CRC (mCRC) in a real-world setting.

METHODS

We performed a retrospective single-center analysis to assess the outcomes of patients with MSS mCRC who were treated with fruquintinib plus anti-PD-1 antibodies subsequent to the failure of standard therapies at the Hunan Cancer Hospital. The overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and toxicity were reviewed and evaluated. The primary endpoint was OS. The impact on OS and PFS was examined using the Cox regression model.

RESULTS

Between 1 January 2019 and 30 June 2022, we enrolled 70 eligible patients. The median follow-up was 17.2 months (range, 5.3-32.9 months). The median OS (mOS) and median PFS (mPFS) were 19.48 and 5.5 months respectively. The ORR was 11.43% and the DCR was 84.29%. Multivariate Cox regression analysis reveals liver metastasis (LM) without local treatment was a risk factor for OS [hazard ratio (HR) =5.31, P=0.0184], whereas that with local treatment (HR =2.19, P=0.263) was not. The most common adverse events were hand-foot syndrome (37.14%), hypertension (34.29%), mucositis oral (32.86%). No serious adverse effects or adverse effect-related deaths were reported. There were no instances of severe adverse effects or deaths related to adverse effects reported.

CONCLUSIONS

Our study indicates that the combination of fruquintinib and anti-PD-1 antibodies can improve the OS and PFS with a tolerable toxicity profile for Chinese patients with refractory MSS mCRC. LM without local therapy is a negative prognostic factor for OS, but those with local treatment can significantly prolong survival. We require additional well-structured, prospective, and extensive studies to confirm and validate these findings.

Significant response from fruquintinib plus anti-PD-1 immunotherapy for microsatellite stable metastatic colorectal cancer with liver and lung metastasis in the third line: case report

Background

There are limited treatment options available for patients with metastatic colorectal cancer (mCRC). About 95% of CRC patients have mismatch repair proficient/microsatellite stable (pMMR/MSS) tumors are virtually unresponsive to programmed cell death protein 1 (PD-1) antibody treatment. This report shows that a patient with pMMR/MSS mCRC achieved significant response and the longest progression-free survival (PFS) of 28 months currently reported from tyrosine kinase inhibitors (TKIs) targeting vascular endothelial growth factor receptor (VEGFR) family (VEGFR-1,2,3) (fruquintinib) plus anti-PD-1 immunotherapy in the third line, providing a new and promising treatment option for some MSS mCRC patients.

Case Description

This case details a 65-year-old male with CRC who was diagnosed with pT4aN2bM0, IIIC, and pMMR/MSS after curative surgery in August 2018. Subsequently, he received adjuvant chemotherapy [FOLFOX (folinic acid, fluorouracil, and oxaliplatin) for 5 cycles], first-line treatment (pelvic radiation plus capecitabine), and second-line treatment [TOMIRI (raltitrexed and irinotecan) plus cetuximab for 2 cycles]. Lung, liver, and pelvic cavity metastases worsened in October 2019. He began receiving the fruquintinib plus PD-1 inhibitor (FP) regimen as third-line treatment and after 3 cycles, the size of the lung lesions was significantly reduced and evaluated as partial response (PR), whereas the liver and pelvic cavity lesions remained stable. As of December 2021, he had received a total of 33 courses of FP regimen. In February 2022, liver metastases progressed. In brief, he achieved a long PFS of 28 months and an overall survival (OS) of 40 months from the third-line treatment. Additionally, the patient only experienced mild proteinuria after the combined treatment and tolerated well.

Conclusions

Fruquintinib combined with immunotherapy could exert good therapeutic effects with safety in MSS mCRC patients. And patients with lung metastasis may be the principal beneficiaries.

The next bastion to be conquered in immunotherapy: microsatellite stable colorectal cancer

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide, and its incidence continues to rise, particularly in developing countries. The advent of immune checkpoint inhibitors (ICIs) has represented a significant advancement in CRC treatment. Deficient mismatch repair (dMMR) or high microsatellite instability (MSI-H) serves as a biomarker for immunotherapy, with dMMR/MSI-H CRC exhibiting significantly better response rates to immunotherapy compared to proficient mismatch repair (pMMR)or microsatellite stable (MSS) CRC. While some progress has been made in the treatment of pMMR/MSS CRC in recent years, it remains a challenging issue in clinical practice. The tumor microenvironment (TME) plays a crucial role not only in the development and progression of CRC but also in determining the response to immunotherapy. Understanding the characteristics of the TME in pMMR/MSS CRC could offer new insights to enhance the efficacy of immunotherapy. In this review, we provide an overview of the current research progress on the TME characteristics and advancements in immunotherapy for pMMR/MSS CRC.

Liver Metastases and Immune Checkpoint Inhibitor Efficacy in Patients With Refractory Metastatic Colorectal Cancer: A Secondary Analysis of a Randomized Clinical Trial

Importance

Immune checkpoint inhibitors (ICIs) have limited activity in microsatellite-stable (MSS) or mismatch repair-proficient (pMMR) colorectal cancer. Recent findings suggest the efficacy of ICIs may be modulated by the presence of liver metastases (LM).

Objective

To investigate the association between the presence of LM and ICI activity in advanced MSS colorectal cancer.

Design, Setting, and Participants

In this secondary analysis of the Canadian Cancer Trials Group CO26 (CCTG CO.26) randomized clinical trial, patients with treatment-refractory colorectal cancer were randomized in a 2:1 fashion to durvalumab plus tremelimumab or best supportive care alone between August 10, 2016, and June 15, 2017. The primary end point was overall survival (OS) with 80% power and 2-sided α = .10. The median follow-up was 15.2 (0.2-22.0) months. In this post hoc analysis performed from February 11 to 14, 2022, subgroups were defined based on the presence or absence of LM and study treatments.

Intervention

Durvalumab plus tremelimumab or best supportive care.

Main Outcomes and Measures

Hazard ratios (HRs) and 90% CIs were calculated based on a stratified Cox proportional hazards regression model. Plasma tumor mutation burden at study entry was determined using a circulating tumor DNA assay. The primary end point of the study was OS, defined as the time from randomization to death due to any cause; secondary end points included progression-free survival (PFS) and disease control rate (DCR).

Results

Of 180 patients enrolled (median age, 65 [IQR, 36-87] years; 121 [67.2%] men; 19 [10.6%] Asian, 151 [83.9%] White, and 10 [5.6%] other race or ethnicity), LM were present in 127 (70.6%). For patients with LM, there was a higher proportion of male patients (94 of 127 [74.0%] vs 27 of 53 [50.9%]; P = .005), and the time from initial cancer diagnosis to study entry was shorter (median, 40 [range, 8-153] vs 56 [range, 14-181] months; P = .001). Plasma tumor mutation burden was significantly higher in patients with LM. Patients without LM had significantly improved PFS with durvalumab plus tremelimumab (HR, 0.54 [90% CI, 0.35-0.96]; P = .08; P = .02 for interaction). Disease control rate was 49% (90% CI, 36%-62%) in patients without LM treated with durvalumab plus tremelimumab, compared with 14% (90% CI, 6%-38%) in those with LM (odds ratio, 5.70 [90% CI, 1.46-22.25]; P = .03). On multivariable analysis, patients without LM had significantly improved OS and PFS compared with patients with LM.

Conclusions and Relevance

In this secondary analysis of the CCTG CO.26 study, the presence of LM was associated with worse outcomes for patients with advanced colorectal cancer. Patients without LM had improved PFS and higher DCR with durvalumab plus tremelimumab. Liver metastases may be associated with poor outcomes of ICI treatment in advanced colorectal cancer and should be considered in the design and interpretation of future clinical studies evaluating this therapy.

Fruquintinib in combination with sintilimab or TAS-102 as third-line or above treatment in patients with metastatic colorectal cancer: a real-world study

Background

For metastatic colorectal cancer (mCRC), the efficacy of third-line or above treatments is not ideal. Combining targeted vascular endothelial growth factor (VEGF) or vascular endothelial growth factor receptor (VEGFR) biological agents with chemotherapy or anti-programmed death receptor 1 (PD-1) treatment can bring longer survival benefits to patients with mCRC compared with the application of a single drug. In this study, fruquintinib was used as the research drug, and the main purpose was to compare the efficacy and safety of fruquintinib in combination with sintilimab (FS) or trifluridine and tipiracil (TAS-102) (FT) in the third-line or above treatment in mCRC patients.

Methods

Based on real-world clinical practice, mCRC patients who progressed after second-line or higher-line chemotherapy regimens and received FS or FT as third-line or above treatment from December 2020 to November 2022 were analyzed. Progression-free survival (PFS) was the primary endpoint. Safety, disease control rate (DCR) and objective response rate (ORR) were secondary end points.

Results

In the FS group, 47 patients received FS, and in the FT group, 45 patients received FT. The DCR values in the FS and FT groups were 80.9% (38/47) and 55.6% (25/45), respectively (P<0.05). The median PFS (mPFS) in the FS group was 6.0 months, and the mPFS in the FT group was 3.5 months (P<0.05). Most adverse events (AEs) were grade 1-2 in severity.

Conclusions

As a third-line or above regimen in mCRC patients, compared to FT, treatment with FS provides a higher DCR and longer mPFS and is better tolerated. The combination of fruquintinib and sintilimab may become a new treatment option for mCRC patients.

Effect of liver metastasis on the efficacy of immune checkpoint inhibitors in cancer patients: a systemic review and meta-analysis

Liver metastasis is a frequent phenomenon in advanced tumor disease. Immune checkpoint inhibitors (ICIs) are a new class of therapeutics that can improve the prognosis of cancer patients. The purpose of this study is to elucidate the relationship between liver metastasis and survival outcomes of patients receiving ICIs treatment. We searched four main databases, including PubMed, EMBASE, Cochrane Library, and Web of Science. Overall survival (OS) and progression-free survival (PFS) were the survival outcomes of our concern. Hazard ratio (HR) with 95% confidence interval (CI) were used to evaluate the relationship between liver metastasis and OS/ PFS. Finally, 163 articles were included in the study. The pooled results showed that patients with liver metastasis receiving ICIs treatment had worse OS (HR=1.82, 95%CI:1.59-2.08) and PFS (HR=1.68, 95%CI:1.49-1.89) than patients without liver metastasis. The effect of liver metastasis on ICIs efficacy differed in different tumor types, and patients with urinary system tumors (renal cell carcinoma OS: HR=2.47, 95%CI:1.76-3.45; urothelial carcinoma OS: HR=2.37, 95%CI:2.03-2.76) had the worst prognosis, followed by patients with melanoma (OS: HR=2.04, 95%CI:1.68-2.49) or non-small cell lung cancer (OS: HR=1.81, 95%CI:1.72-1.91). ICIs efficacy in digestive system tumors (colorectal cancer OS: HR=1.35, 95%CI:1.07-1.71; gastric cancer/ esophagogastric cancer OS: HR=1.17, 95%CI:0.90-1.52) was less affected, and peritoneal metastasis and the number of metastases have a greater clinical significance than liver metastasis based on univariate data. For cancer patients receiving ICIs treatment, the occurrence of liver metastasis is associated with poor prognosis. Different cancer types and metastatic sites may hold a different prognostic effect on the efficacy of ICIs treatment in cancer patients.

Case report: Bullous pemphigoid associated with sintilimab therapy for pMMR/MSS colorectal cancer

Immunotherapy has become a very effective treatment for many cancers. It has a unique set of immune system-related adverse effects, collectively known as immune-related adverse events (irAEs). Skin toxicities are the most common irAEs, of which bullous pemphigoid, although rare, is potentially life-threatening and affects patients’ survival. In this article, we report the treatment of bullous pemphigoid caused by programmed cell death protein-1 (PD-1) in a case of proficient mismatch repair (pMMR)/microsatellite stable (MSS) colorectal cancer. No significant adverse effects were observed in the patient after methylprednisone was tapered to 4 mg twice a day. No new skin lesions occurred recently in the patient and the original skin lesions healed. In particular, the patient’s immunotherapy was not stopped and the best outcome was a partial remission of the disease, lasting for more than 8 months.

Current Landscape and Potential Challenges of Immune Checkpoint Inhibitors in Microsatellite Stable Metastatic Colorectal Carcinoma

Colorectal cancer (CRC) is the third most frequent cancer and the second most common cause of cancer-related death in Europe. High microsatellite instability (MSI-H) due to a deficient DNA mismatch repair (dMMR) system can be found in 5% of metastatic CRC (mCRC) and has been established as a biomarker of response to immunotherapy in these tumors. Therefore, immune checkpoint inhibitors (ICIs) in mCRC with these characteristics were evaluated with results showing remarkable response rates and durations of response. The majority of mCRC cases have high levels of DNA mismatch repair proteins (pMMR) with consequent microsatellite stability or low instability (MSS or MSI-low), associated with an inherent resistance to ICIs. This review aims to provide a comprehensive analysis of the possible approaches to overcome the mechanisms of resistance and evaluates potential biomarkers to establish the role of ICIs in pMMR/MSS/MSI-L (MSS) mCRC.