Survival benefit with adjuvant chemotherapy in stage III microsatellite-high/deficient mismatch repair colon cancer: a systematic review and meta-analysis

Spatial effects of infiltrating T cells on neighbouring cancer cells and prognosis in stage III CRC patients

Colorectal cancer (CRC) is one of the most frequently occurring cancers, but prognostic biomarkers identifying patients at risk of recurrence are still lacking. In this study, we aimed to investigate in more detail the spatial relationship between intratumoural T cells, cancer cells, and cancer cell hallmarks as prognostic biomarkers in stage III colorectal cancer patients. We conducted multiplexed imaging of 56 protein markers at single-cell resolution on resected fixed tissue from stage III CRC patients who received adjuvant 5-fluorouracil (5FU)-based chemotherapy. Images underwent segmentation for tumour, stroma, and immune cells, and cancer cell 'state' protein marker expression was quantified at a cellular level. We developed a Python package for estimation of spatial proximity, nearest neighbour analysis focusing on cancer cell-T-cell interactions at single-cell level. In our discovery cohort (Memorial Sloan Kettering samples), we processed 462 core samples (total number of cells: 1,669,228) from 221 adjuvant 5FU-treated stage III patients. The validation cohort (Huntsville Clearview Cancer Center samples) consisted of 272 samples (total number of cells: 853,398) from 98 stage III CRC patients. While there were trends for an association between the percentage of cytotoxic T cells (across the whole cancer core), it did not reach significance (discovery cohort: p = 0.07; validation cohort: p = 0.19). We next utilised our region-based nearest neighbour approach to determine the spatial relationships between cytotoxic T cells, helper T cells, and cancer cell clusters. In both cohorts, we found that shorter distance between cytotoxic T cells, T helper cells, and cancer cells was significantly associated with increased disease-free survival. An unsupervised trained model that clustered patients based on the median distance between immune cells and cancer cells, as well as protein expression profiles, successfully classified patients into low-risk and high-risk groups (discovery cohort: p = 0.01; validation cohort: p = 0.003). © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

State of the art: Targeting microsatellite instability in gastrointestinal cancers

DNA mismatch repair (MMR) deficiency and the associated microsatellite instability (MSI) phenotype has become a subject of enormous interest in recent years due to the demonstrated efficacy of immune checkpoint inhibitors (ICI) in advanced tumours. Assessing MSI in patients with gastrointestinal tract (GI) cancers is useful to exclude Lynch syndrome, but also to predict benefit for ICI. Following review of the relevant literature, this review article aims to outline the clinicopathologic spectrum of MSI and mismatch repair deficiency (dMMR) in the GI tract, hepatobiliary system and pancreas and discuss the therapeutic consideration in this disease.

Updates on the Management of Colorectal Cancer in Older Adults

Colorectal cancer (CRC) poses a significant global health challenge. Notably, the risk of CRC escalates with age, with the majority of cases occurring in those over the age of 65. Despite recent progress in tailoring treatments for early and advanced CRC, there is a lack of prospective data to guide the management of older patients, who are frequently underrepresented in clinical trials. This article reviews the contemporary landscape of managing older individuals with CRC, highlighting recent advancements and persisting challenges. The role of comprehensive geriatric assessment is explored. Opportunities for treatment escalation/de-escalation, with consideration of the older adult's fitness level. are reviewed in the neoadjuvant, surgical, adjuvant, and metastatic settings of colon and rectal cancers. Immunotherapy is shown to be an effective treatment option in older adults who have CRC with microsatellite instability. Promising new technologies such as circulating tumor DNA and recent phase III trials adding later-line systemic therapy options are discussed. Clinical recommendations based on the data available are summarized. We conclude that deliberate efforts to include older individuals in future colorectal cancer trials are essential to better guide the management of these patients in this rapidly evolving field.

Spatial Effects of Infiltrating T cells on Neighbouring Cancer Cells and Prognosis in Stage III CRC patients

Colorectal cancer (CRC) is one of the most frequently occurring cancers, but prognostic biomarkers identifying patients at risk of recurrence are still lacking. In this study, we aimed to investigate in more detail the spatial relationship between intratumoural T cells, cancer cells, and cancer cell hallmarks, as prognostic biomarkers in stage III colorectal cancer patients. We conducted multiplexed imaging of 56 protein markers at single cell resolution on resected fixed tissue from stage III CRC patients who received adjuvant 5-fluorouracil-based chemotherapy. Images underwent segmentation for tumour, stroma and immune cells, and cancer cell 'state' protein marker expression was quantified at a cellular level. We developed a Python package for estimation of spatial proximity, nearest neighbour analysis focusing on cancer cell - T cell interactions at single-cell level. In our discovery cohort (MSK), we processed 462 core samples (total number of cells: 1,669,228) from 221 adjuvant 5FU-treated stage III patients. The validation cohort (HV) consisted of 272 samples (total number of cells: 853,398) from 98 stage III CRC patients. While there were trends for an association between percentage of cytotoxic T cells (across the whole cancer core), it did not reach significance (Discovery cohort: p = 0.07, Validation cohort: p = 0.19). We next utilized our region-based nearest neighbourhood approach to determine the spatial relationships between cytotoxic T cells, helper T cells and cancer cell clusters. In the both cohorts, we found that lower distance between cytotoxic T cells, T helper cells and cancer cells was significantly associated with increased disease-free survival. An unsupervised trained model that clustered patients based on the median distance between immune cells and cancer cells, as well as protein expression profiles, successfully classified patients into low-risk and high-risk groups (Discovery cohort: p = 0.01, Validation cohort: p = 0.003).

[Novel Treatment Concepts in Patients with Colorectal Carcinomas and High Microsatellite Instability]

Approximately 15% of patients with colorectal cancer show high microsatellite instability (MSI-high) in their tumour tissue. For one third of these patients, there is a hereditary cause for this finding - that leads to the diagnosis of Lynch Syndrome. In combination with clinical findings such as the Amsterdam or the revised Bethesda criteria, MSI-high status has been used as a tool in identifying patients at risk. Today, MSI-status has gained much more importance, due to its impact on treatment decisions. Patients with UICC II cancers should not receive adjuvant treatment. For patients with distant metastases and MSI-high status, immune checkpoint inhibitors can be given as first line therapy - with tremendous success. Novel data show a deep response for immune checkpoint antibodies in patients with locally advanced colon as well as rectal cancer in a neoadjuvant setting. Especially for patients with MSI-high rectal cancer, there might be a novel therapeutic regimen utilising immune checkpoint inhibitors without neoadjuvant radio-chemotherapy and even without surgery. This could lead to a relevant reduction in morbidity in this patient cohort. In conclusion, universal MSI-testing is essential for identifying patients at risk for Lynch syndrome and for optimal decision making in treatment planning.

Emerging evidence of immunotherapy for colorectal cancer

Since the advent of immune checkpoint inhibitors, which modulate the interplay between the tumor cell and immune system, immunotherapy has become widely recognized as a new standard treatment for cancers including microsatellite instability-high (MSI-H) colorectal cancer. Immune checkpoint inhibitors such as pembrolizumab and nivolumab (anti-PD-1 antibodies) that act in the effector phase of T cells and ipilimumab (anti-CTLA-4 antibody) that acts mainly in the priming phase are now in clinical use. These antibodies have shown therapeutic efficacy in MSI colorectal cancer patients who have failed to respond to existing standard therapies. Pembrolizumab is also strongly recommended as first-line therapy for MSI-H metastatic colorectal cancer. Therefore, the MSI status and tumor mutation burden of the tumor should be clarified before starting treatment. Because many patients do not respond to immune checkpoint inhibitors, combination therapies with immune checkpoint inhibitors, including chemotherapy, radiotherapy, or molecularly targeted agents, are being investigated. Furthermore, treatment methods for preoperative adjuvant therapy for rectal cancer are being developed.

A pilot retrospective study of comprehensive nursing care on psychological disorder in colorectal cancer undergoing chemotherapy

BACKGROUND

This pilot study retrospectively evaluated the effects of comprehensive nursing care (CNC) on psychological disorders in patients with colorectal cancer (CC) undergoing chemotherapy.

METHODS

This study analyzed 70 eligible patients' case records of CC undergoing chemotherapy. These records were allocated to a treatment group (n = 35) or a control group (n = 35). All 70 patients in both groups received routine nursing care. In addition, 35 patients in the treatment group also received CNC. The primary outcomes were anxiety, as measured by Self-rating Anxiety Scale, and depression, as assessed by Self-rating Depression Scale. The secondary outcomes were quality of life, as measured by The 36-Item Short Form Health Survey, and adverse events. All outcome data were analyzed before and 3-month after treatment.

RESULTS

At 3-month after treatment, the patients in the treatment group had better outcomes in the Self-rating Anxiety Scale (P<0.01), Self-rating Depression Scale (P<0.01), and The 36-Item Short Form Health Survey (social function, P = .04; emotional role, P = 0.03) than those in the control group. With regard to safety, no treatment-related adverse events were recorded in either group.

CONCLUSION

The findings of this pilot retrospective study showed promising effects of CNC on psychological disorders and quality of life in patients with CC undergoing chemotherapy. However, more high-quality clinical trials are required to confirm these findings.