Exploring immune status in peripheral blood and tumor tissue in association with survival in patients with multi-organ metastatic colorectal cancer.

Colorectal cancer (CRC) raises considerable clinical challenges, including a high mortality rate once the tumor spreads to distant sites. At this advanced stage, more accurate prediction of prognosis and treatment outcome is urgently needed. The role of cancer immunity in metastatic CRC (mCRC) is poorly understood. Here, we explore cellular immune cell status in patients with multi-organ mCRC. We analyzed T cell infiltration in primary tumor sections, surveyed the lymphocytic landscape of liver metastases, and assessed circulating mononuclear immune cells. Besides asking whether immune cells are associated with survival at this stage of the disease, we investigated correlations between the different tissue types; as this could indicate a dominant immune phenotype. Taken together, our analyses corroborate previous observations that higher levels of CD8+ T lymphocytes link to better survival outcomes. Our findings therefore extend evidence from earlier stages of CRC to indicate an important role for cancer immunity in disease control even after metastatic spreading to multiple organs. This finding may help to improve predicting outcome of patients with mCRC and suggests a future role for immunotherapeutic strategies.

Health-Related Quality of Life in Patients With Metastatic Colorectal Cancer Undergoing Systemic Therapy With or Without Maximal Tumor Debulking.

BACKGROUND: Maintaining a sufficient health-related quality of life (HRQoL) is important in the palliative treatment of patients with metastatic colorectal cancer (mCRC). The ORCHESTRA trial (ClinicalTrials.gov identifier: NCT01792934) is designed to prospectively evaluate overall survival benefit and impact on HRQoL of tumor debulking when added to first-line palliative systemic therapy in patients with multiorgan mCRC. In the present study, we report the HRQoL associated with this combination treatment compared with standard systemic therapy. METHODS: Patients included in the ORCHESTRA trial with clinical benefit after 3 or 4 cycles of first-line palliative systemic therapy with fluoropyrimidines and oxaliplatin with or without bevacizumab were randomly assigned to maximal tumor debulking followed by systemic therapy versus systemic therapy alone. Patients completed the EORTC Quality of Life Questionnaire-Core 30 and the Multidimensional Fatigue Inventory questionnaire at prespecified time points during treatment. Between-group differences in HRQoL over time were evaluated with linear mixed model analyses. A pattern mixture approach was applied to correct for missing questionnaires due to progressive disease. RESULTS: A total of 300 patients were randomized to the intervention arm (n=148) or the standard arm (n=152). No statistically significant or clinically relevant differences in HRQoL and fatigue were observed when tumor debulking was added to systemic therapy. In patients of both study arms, HRQoL after 1 year of treatment was not significantly different from HRQoL at the time of randomization. Patients in the intervention arm experienced serious adverse events (SAEs) twice as often as patients in the standard arm (P≤.001). CONCLUSIONS: Maximal tumor debulking in combination with palliative systemic therapy in patients with multiorgan mCRC was significantly associated with more SAEs resulting from local therapy but no difference in HRQoL compared with palliative systemic therapy alone. There is a remarkable lack of association between the occurrence of SAEs and impact on HRQoL.

Dendritic cell phenotype and function in a 3D co-culture model of patient-derived metastatic colorectal cancer organoids.

Colorectal cancer (CRC) remains one of the most aggressive and lethal cancers, with metastasis accounting for most deaths. As such, there is an unmet need for improved therapies for metastatic CRC (mCRC). Currently, the research focus is shifting towards the reciprocal interactions within the tumor microenvironment (TME), which prevent tumor clearance by the immune system. Dendritic cells (DCs) play a key role in the initiation and amplification of anti-tumor immune responses and in driving the clinical success of immunotherapies. Dissecting the interactions between DCs and CRC cells may open doors to identifying key mediators in tumor progression, and possible therapeutic targets. This requires representative, robust and versatile models and tools. Currently, there is a shortage of such in vitro systems to model the CRC TME and its tumor-immune cell interactions. Here we develop and establish a dynamic organotypic 3D co-culture system to recapitulate and untangle the interactions between DCs and patient-derived mCRC tumor organoids. To our knowledge, this is the first study investigating human DCs in co-culture with tumor organoids in a 3D, organotypic setting. This system reveals how mCRC organoids modulate and shape monocyte-derived DCs (MoDCs) behavior, phenotype, and function, within a collagen matrix, using techniques such as brightfield and fluorescence microscopy, flow cytometry, and fluorescence-activated cell sorting. Our 3D co-culture model shows high viability and extensive interaction between DCs and tumor organoids, and its structure resembles patient tissue sections. Furthermore, it is possible to retrieve DCs from the co-cultures and characterize their phenotypic and functional profile. In our study, the expression of activation markers in both mature and immature DCs and their ability to activate T cells were impacted by co-culture with tumor organoids. In the future, this direct co-culture platform can be adapted and exploited to study the CRC-DC interplay in more detail, enabling novel and broader insights into CRC-driven DC (dys)function.

A specific microRNA profile as predictive biomarker for systemic treatment in patients with metastatic colorectal cancer.

BACKGROUND: Palliative systemic therapy is currently standard of care for patients with extensive metastatic colorectal cancer (mCRC). A biomarker predicting chemotherapy benefit which prevents toxicity from ineffective treatment is urgently needed. Therefore, a previously developed tissue-derived microRNA profile to predict clinical benefit from chemotherapy was evaluated in tissue biopsies and serum from patients with mCRC. METHODS: Samples were prospectively collected from patients (N = 132) who were treated with capecitabine or 5-FU/LV with oxaliplatin ± bevacizumab. Response evaluation was performed according to RECIST 1.1 after three or four cycles, respectively. Baseline tissue and serum miRNAs expression levels of miR-17-5p, miR-20a-5p, miR-30a-5p, miR-92a-3p, miR-92b-3p, and miR-98-5p were quantified with RT-qPCR and droplet digital PCR, respectively. Combined predictive performance of selected variables was tested using logistic regression analysis. RESULTS: From 132 patients, 81 fresh frozen tissue biopsies from metastases and 93 serum samples were available. Based on expression levels of miRNAs in tissue, progressive disease could be predicted with an AUC of 0.85 (95% CI:0.72-0.91) and response could be predicted with an AUC of 0.70 (95% CI:0.56-0.80). This did not outperform clinical parameters alone (respectively P = .14 and P = .27). Expression levels of miR-92a-3p and miR-98-5p in serum significantly improved the predictive value of clinical parameters for response to chemotherapy (AUC 0.74, 95% CI:0.64-0.84, P = .003) in this cohort. CONCLUSIONS: The additive predictive value to clinical parameters of the tissue-derived six miRNA profile for clinical benefit could not be validated in patients with mCRC treated with first-line systemic therapy. Although miR-92a-3p and miR-98-5p serum levels improved the predictive value of clinical parameters, it remained insufficient for clinical decision-making.

Safety and Feasibility of Additional Tumor Debulking to First-Line Palliative Combination Chemotherapy for Patients with Multiorgan Metastatic Colorectal Cancer.

INTRODUCTION: Local treatment of metastases is frequently performed in patients with multiorgan metastatic colorectal carcinoma (mCRC) analogous to selected patients with oligometastatic disease for whom this is standard of care. The ORCHESTRA trial (NCT01792934) was designed to prospectively evaluate overall survival benefit from tumor debulking in addition to chemotherapy in patients with multiorgan mCRC. Here, we report the preplanned safety and feasibility evaluation after inclusion of the first 100 patients. METHODS: Patients were eligible if at least 80% tumor debulking was deemed feasible by resection, radiotherapy and/or thermal ablative therapy. In case of clinical benefit after three or four cycles of respectively 5-fluorouracil/leucovorin or capecitabine and oxaliplatin ± bevacizumab patients were randomized to tumor debulking followed by chemotherapy in the intervention arm, or standard treatment with chemotherapy. RESULTS: Twelve patients dropped out prior to randomization for various reasons. Eighty-eight patients were randomized to the standard (n = 43) or intervention arm (n = 45). No patients withdrew after randomization. Debulking was performed in 82% (n = 37). Two patients had no lesions left to treat, five had progressive disease, and one patient died prior to local treatment. In 15 patients (40%) 21 serious adverse events related to debulking were reported. Postoperative mortality was 2.7% (n = 1). After debulking chemotherapy was resumed in 89% of patients. CONCLUSION: Tumor debulking is feasible and does not prohibit administration of palliative chemotherapy in the majority of patients with multiorgan mCRC, despite the occurrence of serious adverse events related to local treatment. IMPLICATIONS FOR PRACTICE: This first prospective randomized trial on tumor debulking in addition to chemotherapy shows that local treatment of metastases is feasible in patients with multiorgan metastatic colorectal cancer and does not prohibit administration of palliative systemic therapy, despite the occurrence of serious adverse events related to local treatment. The trial continues accrual, and overall survival (OS) data and quality of life assessment are collected to determine whether the primary aim of >6 months OS benefit with preserved quality of life will be met. This will support evidence-based decision making in multidisciplinary colorectal cancer care and can be readily implemented in daily practice.

CD276-Positive Circulating Endothelial Cells Do Not Predict Response to Systemic Therapy in Advanced Colorectal Cancer.

CD276 can discriminate between tumor derived and normal CECs (circulating endothelial cells). We evaluated whether CD276+CEC is a clinically relevant biomarker to predict response to palliative systemic therapy in patients with metastatic colorectal cancer (mCRC). Samples were prospectively collected from patients with mCRC enrolled in the ORCHESTRA trial (NCT01792934). At baseline and after three cycles of 5-fluorouracil/leucovorin and oxaliplatin ± bevacizumab, CECs were measured by flowcytometry (CD34+CD45negCD146+DNA+; and CD276+). A clinically relevant cut-off value of (CD276+)CECs was determined as 100% sensitivity (and 80% specificity in 95% confidence interval) identifying patients with progressive disease within 6 months. There were 182 baseline samples and 133 follow up samples available for analysis. CEC and CD276+CEC counts significantly increased during treatment from 48 to 90 CEC/4 mL (p = 0.00) and from 14 to 33 CD276+CEC/4 mL (p = 0.00) at baseline and at first evaluation, respectively. CEC and CD276+CEC counts were not predictive for poor response (area under the curve (AUC) 0.53 for CEC and AUC 0.52 for CD276+CEC). Despite numerical changes during therapy, CEC and CD276+CEC counts do not adequately predict poor response to first line palliative systemic therapy in patients with mCRC.

The value of tumour debulking for patients with extensive multi-organ metastatic colorectal cancer.

Local treatment of metastases by surgical resection or other ablative therapies is technically feasible in an increasing number of patients with multi-organ metastatic cancer. This results in a growing debate on whether patients with extensive disease, that is traditionally deemed unresectable, may benefit from local treatment of metastases when added to standard palliative systemic therapy. For selected patients with oligometastatic colorectal cancer, local treatment of metastases has become the standard of care based on retrospective reports showing long-term survival rates. In addition to systemic therapy, preliminary evidence suggests that patients with extensive metastatic colorectal cancer may also benefit from local treatment. Here, we present the future perspectives based on the available literature on local treatment approaches in colorectal cancer.