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Diseases of the Colon and Rectum Jun 2024In April 2023, the National Comprehensive Cancer Network endorsed neoadjuvant immunotherapy for select patients with nonmetastatic mismatch repair deficient colon...
BACKGROUND
In April 2023, the National Comprehensive Cancer Network endorsed neoadjuvant immunotherapy for select patients with nonmetastatic mismatch repair deficient colon cancer. Approximately 15% of incident colon cancers are mismatch repair deficient, resulting in a distinct molecular subtype with high microsatellite instability that is responsive to immune checkpoint inhibition.
OBJECTIVE
To describe the existing evidence supporting neoadjuvant immunotherapy for mismatch repair deficient, microsatellite unstable nonmetastatic colon cancer.
DATA SOURCES
A medical librarian performed PubMed, Embase, and Web of Science searches most recently on April 24, 2023. The PubMed search was re-run on September 26, 2023, to identify any additional studies published between April 24 and September 26, 2023.
STUDY SELECTION
Two authors screened titles and abstracts in the published studies. The inclusion criteria were 1) English language, 2) adults with primary cancer of the colon, 3) nonmetastatic disease, 4) neoadjuvant immunotherapy, and 5) reporting on 10 or more cases.
INTERVENTION
Neoadjuvant immunotherapy.
MAIN OUTCOME MEASURES
Safety (grade 3+ treatment-related adverse events) and efficacy (complete pathologic responses).
RESULTS
From 7691 studies identified, 6370 were screened and 8 were included. Various agents, dosing regimens, and treatment durations were used, with durations of immunotherapy ranging from 1 to 16 cycles. Complete R0 resections were consistently achieved in 98% to 100% of resections. Of patients who received neoadjuvant immunotherapy and underwent resection, 50% to 91% had ypT0N0 pathology. The safety profiles were generally favorable, with grade 1 to 2 treatment-related adverse events (mostly immune-related) during immunotherapy reported in 22.2% to 70% of patients. Postoperative complications after neoadjuvant immunotherapy were reassuring, with no severe complications reported.
LIMITATIONS
Small number of heterogeneous and uncontrolled studies precluding a meta-analysis.
CONCLUSIONS
Neoadjuvant immune checkpoint inhibition is associated with high rates of pathologic complete responses in locally advanced colon cancer. The literature is limited, particularly for postoperative outcomes, and more studies are needed to understand the safety and positioning of these regimens in the neoadjuvant context.
Topics: Humans; Neoadjuvant Therapy; Colonic Neoplasms; Immunotherapy; DNA Mismatch Repair; Immune Checkpoint Inhibitors; Microsatellite Instability
PubMed: 38479009
DOI: 10.1097/DCR.0000000000003263 -
Diagnostics (Basel, Switzerland) May 2024Microsatellite Instability (MSI-H) occurs in approximately 15% of non-metastatic colon cancers, influencing patient outcomes positively compared to microsatellite stable... (Review)
Review
Microsatellite Instability (MSI-H) occurs in approximately 15% of non-metastatic colon cancers, influencing patient outcomes positively compared to microsatellite stable (MSS) cancers. This systematic review focuses on the prognostic significance of KRAS, NRAS, and BRAF mutations within MSI-H colon cancer. Through comprehensive searches in databases like MEDLINE, EMBASE, and others until 1 January 2024, we selected 8 pertinent studies from an initial pool of 1918. These studies, encompassing nine trials and five observational studies involving 13,273 patients, provided insights into disease-free survival (DFS), survival after recurrence, and overall survival. The pooled data suggest that while KRAS and BRAF mutations typically predict poorer outcomes in MSS colorectal cancer, their impact is less pronounced in MSI contexts, with implications varying across different stages of cancer and treatment responses. In particular, adverse effects of these mutations manifest significantly upon recurrence rather than affecting immediate DFS. Our findings confirm the complex interplay between genetic mutations and MSI status, emphasizing the nuanced role of MSI in modifying the prognostic implications of KRAS, NRAS, and BRAF mutations in colon cancer. This review underscores the importance of considering MSI alongside mutational status in the clinical decision-making process, aiming to tailor therapeutic strategies more effectively for colon cancer patients.
PubMed: 38786299
DOI: 10.3390/diagnostics14101001 -
Cancer Treatment Reviews Jun 2024Gastric cancer (GC), known for its unfavorable prognosis, has been classified in four distinct molecular subtypes. These subtypes not only exhibit differences in their... (Review)
Review
BACKGROUND
Gastric cancer (GC), known for its unfavorable prognosis, has been classified in four distinct molecular subtypes. These subtypes not only exhibit differences in their genome and transcriptome but also in the composition of their tumor immune microenvironment. The microsatellite instable (MSI) and Epstein-Barr virus (EBV) positive GC subtypes show clear clinical benefits from immune checkpoint blockade, likely due to a neoantigen-driven and virus-driven antitumor immune response and high expression of immune checkpoint molecule PD-L1. However, even within these subtypes response to checkpoint inhibition is variable, which is potentially related to heterogeneity in the tumor immune microenvironment (TIME) and expression of co-inhibitory molecules. We conducted a systematic review to outline the current knowledge about the immunological features on the TIME of MSI and EBV + GCs.
METHODS
A systematic search was performed in PubMed, EMBASE and Cochrane Library. All articles from the year 1990 and onwards addressing immune features of gastric adenocarcinoma were reviewed and included based on predefined in- and exclusion criteria.
RESULTS
In total 5962 records were screened, of which 139 were included that reported immunological data on molecular GC subtypes. MSI and EBV + GCs were reported to have a more inflamed TIME compared to non-MSI and EBV- GC subtypes. Compared to microsatellite stable (MSS) tumors, MSI tumors were characterized by higher numbers of CD8 + and FoxP3 + T cells, and tumor infiltrating pro- and anti-inflammatory macrophages. HLA-deficiency was most common in MSI tumors compared to other molecular GC subtypes and associated with lower T and B cell infiltrates compared to HLA-proficient tumors. EBV + was associated with a high number of CD8 + T cells, Tregs, NK cells and macrophages. Expression of PD-L1, CTLA-4, Granzyme A and B, Perforin and interferon-gamma was enriched in EBV + tumors. Overall, MSI tumors harbored a more heterogeneous TIME in terms of immune cell composition and immune checkpoints compared to the EBV + tumors.
DISCUSSION AND CONCLUSION
MSI and EBV + GCs are highly Handbook for Conducting a Literature-Based Health Assessment Using OHAT Approach for Systematic Review and Evidence Integration.; 2019pro-inflammatory immune cell populations. Although studies on the direct comparison of EBV + and MSI tumors are limited, EBV + tumors show less intra-subgroup heterogeneity compared to MSI tumors. More studies are needed to identify how Intra-subgroup heterogeneity impacts response to immunotherapy efficacy.
Topics: Humans; Stomach Neoplasms; Tumor Microenvironment; Epstein-Barr Virus Infections; DNA Mismatch Repair; Herpesvirus 4, Human; Microsatellite Instability
PubMed: 38669788
DOI: 10.1016/j.ctrv.2024.102737 -
Journal of Cancer Research and Clinical... Mar 2024The clinical significance of tertiary lymphoid structure (TLS) in gastric cancer (GC) was uncertain. (Meta-Analysis)
Meta-Analysis
Analyzing the associations between tertiary lymphoid structures and postoperative prognosis, along with immunotherapy response in gastric cancer: findings from pooled cohort studies.
BACKGROUND
The clinical significance of tertiary lymphoid structure (TLS) in gastric cancer (GC) was uncertain.
METHODS
A systematic search was performed in public databases for eligible studies as of April 2, 2023. Meta-analyses were performed to interrogate the associations between TLS levels and prognosis and immunotherapy response of GC. Bioinformatic analyses based on the nine-gene signature of TLS were further conducted to capture the biological underpinnings.
RESULTS
Eleven studies containing 4224 GC cases were enrolled in the meta-analysis. TLS levels positively correlated with smaller tumor size, earlier T stage and N stage. Moreover, higher TLS levels were detected in diffuse and mix subtypes of GC (P < 0.001). Higher TLS levels strongly predicted favorable postoperative overall survival of GC, with HR of 0.36 (95%CI 0.26-0.50, P < 0.001) and 0.55 (95%CI 0.45-0.68, P < 0.001) of univariate and multivariate Cox analysis, respectively. Higher TLS levels were also in favor of the treatment response of anti-PD-1 inhibitors as later-line therapy of GC. TLS levels positively correlated with immune effector cells infiltration, diversity and richness of T cell receptor and B cell receptor repertoire, immune checkpoint genes expression, and immune-related genes mutation of GC in the TCGA-STAD cohort, representing higher immunogenicity and immunoactivity. Moreover, moderate accuracy of TLS levels in predicting benefit from anti-PD-1 inhibitors in the PRJEB25780 cohort was also validated (AUC 0.758, 95%CI 0.583-0.933), higher than the microsatellite instability-score and Epstein-Barr virus status.
CONCLUSIONS
TLS levels demonstrated potential in predicting the postoperative prognosis and immunotherapy response of GC.
Topics: Humans; Cohort Studies; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Immune Checkpoint Inhibitors; Immunotherapy; Prognosis; Stomach Neoplasms; Tertiary Lymphoid Structures; Tumor Microenvironment
PubMed: 38519621
DOI: 10.1007/s00432-024-05672-y -
The Oncologist May 2024The use of immune checkpoint inhibitors (ICIs) has revolutionized cancer care, particularly in immune-inflamed tumors and tumors with a high mutational burden, like...
The use of immune checkpoint inhibitors (ICIs) has revolutionized cancer care, particularly in immune-inflamed tumors and tumors with a high mutational burden, like microsatellite instable colorectal cancer (CRC). However, their effectiveness in microsatellite stable (MSS) CRC is limited. This systematic review aims to evaluate the efficacy of ICIs in MSS CRC and explore promising combination strategies. A comprehensive search from the Web of Science, Medline, and Embase databases, for studies published until 14 November 2022, identified 53 clinical trials included in the review. ICI monotherapy or ICI-ICI combinations demonstrated limited clinical activity for patients with MSS CRC, with overall response rates below (ORR) 10% in most studies. The ICI and tyrosine kinase inhibitor (TKI) garnered ORRs ranging from 10% to 40% and indicated a higher benefit for patients, particularly those without active liver metastases. The combination of ICIs with anti-VEGF agents showed modest ORRs, especially in the earlier treatment lines and in combination with chemotherapy. While these combinations could lead to modest improvements, well-defined biomarkers for long-term benefit are yet to be delineated. Combinations involving BRAF inhibitors with ICIs were studied, showing promising responses with combination approaches in molecularly defined subgroups. In conclusion, while ICI monotherapy has limited efficacy in MSS CRC, combination strategies hold promise to enhance survival outcomes. Further research is necessary to identify optimal combination approaches, predictive biomarkers for treatment response, as well as enrollment according to tumor molecular characteristics.
Topics: Humans; Immune Checkpoint Inhibitors; Colorectal Neoplasms; Microsatellite Instability
PubMed: 38309719
DOI: 10.1093/oncolo/oyae013 -
Cancer Causes & Control : CCC Feb 2024African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced...
PURPOSE
African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced stage at diagnosis. Recent evidence indicates that differences in tumor characteristics may also underlie disparities in mortality. To highlight recent findings and areas for investigation, we completed the first systematic review of racial disparities in CRC tumor prognostic markers, including clinicopathological markers, microsatellite instability (MSI), oncogene mutations, and novel markers, including cancer stem cells and immune markers.
METHODS
Relevant studies were identified via PubMed, limited to original research published within the last 10 years. Ninety-six articles were identified that compared the prevalence of mortality-related CRC tumor characteristics in African Americans (or other African ancestry populations) to White cases.
RESULTS
Tumors from African ancestry cases are approximately 10% more likely to contain mutations in KRAS, which confer elevated mortality and resistance to epidermal growth factor receptor inhibition. Conversely, African Americans have approximately 50% lower odds for BRAF-mutant tumors, which occur less frequently but have similar effects on mortality and therapeutic resistance. There is less consistent evidence supporting disparities in mutations for other oncogenes, including PIK3CA, TP53, APC, NRAS, HER2, and PTEN, although higher rates of PIK3CA mutations and lower prevalence of MSI status for African ancestry cases are supported by recent evidence. Although emerging evidence suggests that immune markers reflecting anti-tumor immunity in the tumor microenvironment may be lower for African American cases, there is insufficient evidence to evaluate disparities in other novel markers, cancer stem cells, microRNAs, and the consensus molecular subtypes.
CONCLUSION
Higher rates of KRAS-mutant tumors in in African Americans may contribute to disparities in CRC mortality. Additional work is required to understand whether emerging markers, including immune cells, underlie the elevated CRC mortality observed for African Americans.
Topics: Humans; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins p21(ras); Racial Groups; Colorectal Neoplasms; Mutation; Microsatellite Instability; Biomarkers; Tumor Microenvironment
PubMed: 37688643
DOI: 10.1007/s10552-023-01783-y -
Heliyon May 2024Endometrial carcinoma is the most widespread gynecological cancer, with increasing morbidity and mortality. Pembrolizumab, a monoclonal antibody that targets PD1...
OBJECTIVE
Endometrial carcinoma is the most widespread gynecological cancer, with increasing morbidity and mortality. Pembrolizumab, a monoclonal antibody that targets PD1 receptor tumors, is approved for patients with microsatellite instability-high (MSI-H) solid tumors. Many clinical trials and observational studies have been conducted to assess the safety and efficacy of Lenvatinib and Pembrolizumab combination therapy in the setting of endometrial cancer. However, results have been inconsistent, and current data is based on a heterogeneous population. The primary objective was to assess the safety and efficacy of Lenvatinib plus Pembrolizumab for endometrial cancer.
DATA SOURCES
The search was conducted from inception from four databases; PubMed, Google Scholar, the Cochrane Library, and ClinicalTrials.gov. The electronic database search was conducted from inception to August 20, 2023.
STUDY ELIGIBILITY CRITERIA
We considered randomized controlled trials and single-arm observational studies, i.e. cohort, case-control and cross-sectional studies.
METHODOLOGY
We performed a single-arm meta-analysis, involving 7 studies having a total of 495 patients with endometrial cancer were eventually included which had the following outcomes: Complete response, Partial response, Progression-free survival, stable disease, progressive disease, safety outcomes, Adverse events, and the total number of deaths.
RESULTS
Our results showed that 88.6 % of the patients were positive for non-MSI-H/pMMR tumors (95 % CI = 0.825-0.927) whereas 6.5 % (95 % CI = 3.8-9.8 %) of the patients for MSI-H/dMMR tumors. The pooled objective response of endometrial cancer patients treated with Lenvatinib and Pembrolizumab was 36.5 % (95 % CI = 0.258-0.471), the pooled estimate of complete and partial response was 47 % (95 % CI = 0.024-0.070) and 31.3 % (95 % CI = 0.230-0.396). 38.2 % patients had stable disease (95 % CI = 0.329-0.435) and 24.0 % patients had progressive disease (95 % CI = 0.103-0.378). The pooled median progression-free survival was 5.97 (95 % CI 5.43-7.63) months and, whereas the median overall survival was 17.19 months (95 % CI 15.34-19.31). All grade adverse events occurred in 85 % and Grade 3 or worse adverse events occurred in 39 % of patients during the therapy whereas death occurred in 23.8 % during the treatment.
CONCLUSION
The results of this meta-analysis concludes that although the combined treatment of a Lenvatinib and Pembrolizumab had a PFS and OS that was inferior to the standard therapy used to treat advanced and recurrent endometrial cancer, it is still a novel treatment and shows potential for further research with a greater sample size.
PubMed: 38720703
DOI: 10.1016/j.heliyon.2024.e30257 -
Asia-Pacific Journal of Clinical... Feb 2024Gastric epithelial tumors exhibit morphological heterogeneity, diverse biological behaviors, and different oncopathological pathways. The Cancer Genome Atlas (TCGA)... (Meta-Analysis)
Meta-Analysis
Molecular profile of gastric adenocarcinoma, relevant epidemiological factors - Systematic review and meta-analysis relating sex with Epstein-Barr virus and unstable microsatellites subtypes.
INTRODUCTION
Gastric epithelial tumors exhibit morphological heterogeneity, diverse biological behaviors, and different oncopathological pathways. The Cancer Genome Atlas (TCGA) proposed a molecular classification of gastric adenocarcinomas based on genetic and molecular findings, which shows particular characteristics of diagnosis, prognosis, and indirectly, therapeutic alternatives. Within this classification, Epstein-Barr virus-positive (EBV+) and high microsatellite instability (MSI-H) subtypes stand out as subtypes that present a less aggressive biological behavior and a highly mutilated phenotype. This study conducted a systematic review with an emphasis on epidemiological and prognostic factors based on the molecular classification proposed by TCGA.
METHODS
A broad, comprehensive, and reproducible search with methodological rigor was conducted for study selection using the ROBINS-I and GRADEpro protocols and appropriate combinations of keywords.
RESULTS
A total of 25 studies were selected: six with a complete classification similar to TCGA and 19 with a distinction between MSI-H and EBV+. The application of meta-analysis calculations reinforces the prevalence of positive Epstein-Barr adenocarcinomas in males and high microsatellite instability in females, with a high level of certainty of evidence and low risk of bias in the analyzed studies due to the rigorous methods used.
CONCLUSION
The molecular classification proposed by TCGA shows limited dissemination, with MSI-H and EBV+ subtypes being the most researched, probably due to the benefit of the association with immunotherapies. However, the subclassification cannot be restricted to less than a quarter of the cases, and improvements in this aspect are urgent for the construction of knowledge on this important topic of global health.
Topics: Male; Female; Humans; Herpesvirus 4, Human; Epstein-Barr Virus Infections; Microsatellite Instability; Microsatellite Repeats; Stomach Neoplasms; Adenocarcinoma
PubMed: 37932908
DOI: 10.1111/ajco.14032 -
Archives of Gynecology and Obstetrics Nov 2023
Meta-Analysis
Topics: Female; Humans; Microsatellite Instability; Carcinoma, Endometrioid; Endometrial Neoplasms
PubMed: 36374348
DOI: 10.1007/s00404-022-06777-w -
Therapeutic Advances in Medical Oncology 2024Perioperative chemotherapy (CT) is an established therapeutic approach for patients diagnosed with stage IB-III gastric cancer (GC).
BACKGROUND
Perioperative chemotherapy (CT) is an established therapeutic approach for patients diagnosed with stage IB-III gastric cancer (GC).
OBJECTIVES
This study aimed to investigate the efficacy of this approach in individuals with GC exhibiting high microsatellite instability (MSI-H).
DESIGN
A systematic review was conducted, including studies that provided data on (neo)adjuvant CT outcomes in patients with MSI-H GC.
METHODS
Systematic searches were conducted in PubMed, Cochrane Central of Controlled Trials, and Embase databases. Data were aggregated using hazard ratios (HRs) to compare overall survival between CT and surgery.
RESULTS
Data analysis from 23 studies, including 22,011 patients, revealed that the prevalence of MSI-H is 9.8%. Administration of adjuvant or perioperative CT did not significantly reduce the risk of death or relapse in patients with MSI-H GC (HR = 0.8, 95% CI 0.54-1.16; = 0.24 and HR = 0.84, 95% CI 0.59-1.18; = 0.31, respectively).
CONCLUSION
Chemotherapy did not benefit patients diagnosed with MSI-H nonmetastatic GC but rather will be integrated with immune checkpoint inhibitors in the near future.
PubMed: 38435432
DOI: 10.1177/17588359241231259