Combination of primary tumor location and mismatch repair status guides adjuvant chemotherapy in stage II colon cancer

Identification of Comprehensive Biomarkers in Patients With Mismatch Repair-Deficient Colon Adenocarcinoma Based on Parallel Multiomics

Immunocheckpoint inhibitors have shown impressive efficacy in patients with colon cancer and other types of solid tumor that are mismatch repair-deficient (dMMR). Currently, PCR-capillary electrophoresis is one of the mainstream detection methods for dMMR, but its accuracy is still limited by germline mismatch repair (MMR) mutations, the functional redundancy of the MMR system, and abnormal methylation of MutL Homolog 1 promoter. Therefore, this study aimed to develop new biomarkers for dMMR based on artificial intelligence (AI) and pathologic images, which may help to improve the detection accuracy. To screen for the differential expression genes (DEGs) in dMMR patients and validate their diagnostic and prognostic efficiency, we used the expression profile data from the Cancer Genome Atlas (TCGA). The results showed that the expression of Immunoglobulin Lambda Joining 3 in dMMR patients was significantly downregulated and negatively correlated with the prognosis. Meanwhile, our diagnostic models based on pathologic image features showed good performance with area under the curves (AUCs) of 0.73, 0.86, and 0.81 in the training, test, and external validation sets (Jiangsu Traditional Chinese Medicine Hospital cohort). Based on gene expression and pathologic characteristics, we developed an effective prognosis model for dMMR patients through multiple Cox regression analysis (with AUC values of 0.88, 0.89, and 0.88 at 1-, 3-, and 5-year intervals, respectively). In conclusion, our results showed that Immunoglobulin Lambda Joining 3 and nucleus shape-related parameters (such as nuclear texture, nuclear eccentricity, nuclear size, and nuclear pixel intensity) were independent diagnostic and prognostic factors, suggesting that they could be used as new biomarkers for dMMR patients.

Adjuvant Therapy for Stage II Colon Cancer: ASCO Guideline Update

PURPOSE

To develop recommendations for adjuvant therapy for patients with resected stage II colon cancer.

METHODS

ASCO convened an Expert Panel to conduct a systematic review of relevant studies and develop recommendations for clinical practice.

RESULTS

Twenty-one observational studies and six randomized controlled trials met the systematic review inclusion criteria.

RECOMMENDATIONS

Adjuvant chemotherapy (ACT) is not routinely recommended for patients with stage II colon cancer who are not in a high-risk subgroup. Patients with T4 tumors are at higher risk of recurrence and should be offered ACT, whereas patients with other high-risk factors, including sampling of fewer than 12 lymph nodes in the surgical specimen, perineural or lymphatic invasion, poorly or undifferentiated tumor grade, intestinal obstruction, tumor perforation, or grade BD3 tumor budding, may be offered ACT. The addition of oxaliplatin to fluoropyrimidine-based ACT is not routinely recommended, but may be offered as a result of shared decision making. Patients with mismatch repair deficiency/microsatellite instability tumors should not be routinely offered ACT; if the combination of mismatch repair deficiency/microsatellite instability and high-risk factors results in a decision to offer ACT, oxaliplatin-containing chemotherapy is recommended. Duration of oxaliplatin-containing chemotherapy is also addressed, with recommendations for 3 or 6 months of treatment with capecitabine and oxaliplatin or fluorouracil, leucovorin, and oxaliplatin, with decision making informed by key evidence of 5-year disease-free survival in each treatment subgroup and the rate of adverse events, including peripheral neuropathy.Additional information is available at www.asco.org/gastrointestinal-cancer-guidelines.

Extracellular Vesicles Reflect the Efficacy of Wheatgrass Juice Supplement in Colon Cancer Patients During Adjuvant Chemotherapy

Introduction

Colorectal cancer (CC) is the third most common type of cancer, accounting for 10% of all cancer cases. Adjuvant chemotherapy is recommended in stages II–III CC. Wheatgrass juice (WGJ) from wheat seeds has high nutritional values, may induce synergistic benefits to chemotherapy and may attenuate chemotherapy-related side effects. Extracellular vesicles (EVs) are subcellular membrane blebs. EVs include exosomes (generated in the endosome, in size <150 nm) and microvesicles (shed from the plasma cell membrane) provide information on their parental cells and play a role in intercellular communication. We aimed to elucidate the effects of chemotherapy administration with supportive treatment of WGJ on CC patients’ EVs characteristics.

Methods

EVs were isolated from the blood samples of 15 healthy controls (HCs) and 50 CC patients post-surgery, treated by chemotherapy, with or without additional daily WGJ. Blood samples were taken before, during, and at the end of chemotherapy. EVs were characterized by size, concentration, membrane antigens and cytokine content using nanoparticle-tracking analysis, western blot, flow cytometry, and protein array methods.

Results

EVs were found to be similar by size and concentration with reduced levels of exosome markers (CD81) on samples at the end of combined treatment (chemotherapy and WGJ). Higher levels of endothelial EVs, which may indicate impairment of the vascular endothelial cells during treatment, were found in CC patients treated by chemotherapy only compared to those with chemotherapy and daily WGJ. Also, EVs thrombogenicity was lower in patients added WGJ compared to patients who had only chemotherapy (levels of tissue factor p = 0.029 and endothelial protein C receptor p = 0.005). Following treatments, levels of vascular endothelial growth factor receptors (VEGFR-1) and the majority of growth-factors/pro-inflammatory cytokines were higher in EVs of patients treated by chemotherapy only than in EVs obtained from patients with the combined treatment.

Conclusion

Daily consumption of WGJ during chemotherapy may reduce vascular damage and chemotherapy-related thrombogenicity, growth factors and cytokines, as reflected by the characteristics of patient’s EVs.

Mismatch repair status predicts survival after adjuvant treatment in stage II colon cancer patients

BACKGROUND AND OBJECTIVES

Stage II colon cancer is primarily a surgical disease. Only a still not well-defined subset of patients may benefit from postoperative adjuvant chemotherapy. The relationship between adjuvant chemotherapy and survival after relapse is furthermore still not definitely explored in this group of patients. A number of reports suggest some association between defective mismatch repair (dMMR) and colorectal cancer stage II prognosis, but due to contradictory results from existing studies, the exact predictive role is still not fully understood.

METHODS

Retrospective multicenter study including 451 stage II colon cancer patients. The proficiency or deficiency of mismatch repair was tested using immunohistochemistry and analyzed in relationship to two survival outcomes: overall survival (OS) and postrelapse survival.

RESULTS

Patients with dMMR (20.4%) derived no OS benefit from adjuvant chemotherapy (hazard ratio [HR], 1.05; 95% confidence interval [CI], 0.47-2.38; P = .897). Patients with proficient mismatch repair (pMMR) tumors receiving adjuvant chemotherapy had the significantly better OS in comparison to those not receiving chemotherapy (HR, 0.54; 95% CI, 0.35-0.82; P = .004). This relationship remained significant in multivariable analysis (HR, 0.42; 95% CI, 0.22-0.78; P = .007). Patients with pMMR relapsing after adjuvant treatment lived significantly longer than those relapsing without previous adjuvant treatment (HR, 0.55; 95% CI, 0.32-0.96; P = .033) and this result remained significant in the multivariable model (HR, 0.49; 95% CI, 0.26-0.93; P = .030).

CONCLUSION

In stage II CC patients, adjuvant chemotherapy improves therapeutic outcomes only in patients with pMMR tumors. Survival after relapse in patients having received adjuvant chemotherapy is significantly longer for patients with pMMR. No survival benefit from adjuvant chemotherapy was seen among patients with dMMR tumors.