The association of postoperative morbidity and age on 5-year survival after colorectal surgery in the elderly population: a nationwide cohort study.

AIM: This study aimed to evaluate the association of age and postoperative morbidity on 5-year overall survival (OS) after elective surgery for colorectal cancer. METHOD: Patients undergoing elective, curatively intended surgery for colorectal cancer Union for International Cancer Control Stages I-III between January 2014 and December 2019 were selected from four Danish nationwide healthcare databases. Patients were divided into four groups: group I 65-69 years old; group II 70-74 years old; group III 75-79 years old; and group IV ≥80 years old. Propensity score matching was used to reduce potential confounding bias. The primary outcome was the association of age and postoperative morbidity with 5-year OS. The secondary outcome was conditional survival, given that the patient had already survived the first 90 days after surgery. RESULTS: After propensity score matching with a 1:1 ratio, group II contained 2221 patients; group III 952 patients; and group IV 320 patients. There was no significant difference in 5-year OS between group I (reference) and groups II and III (P = 0.4 and P = 0.9, respectively). Patients with severe postoperative complications within 30 days after surgery had a significantly decreased OS (P < 0.01); however, when patients who died within the first 90 days were excluded from the analysis, the differences in 5-year OS were less pronounced across all age groups. CONCLUSION: Postoperative morbidity, and not patient age, was associated with a lower 5-year OS. Long-term survival for patients who experience a complication is similar to patients who did not have a complication when conditioning on 90 days of survival.

Endoscopic calcium electroporation for colorectal cancer: a phase I study.

Background and study aims Colorectal cancer is one of the most common malignancies, with approximately 20 % of patients having metastatic disease. Local symptoms from the tumor remain a common issue and affect quality of life. Electroporation is a method to permeabilize cell membranes with high-voltage pulses, allowing increased passage of otherwise poorly permeating substances such as calcium. The aim of this study was to determine the safety of calcium electroporation for advanced colorectal cancer. Patients and methods Six patients with inoperable rectal and sigmoid colon cancer were included, all presenting with local symptoms. Patients were offered endoscopic calcium electroporation and were followed up with endoscopy and computed tomography/magnetic resonance scans. Biopsies and blood samples were collected at baseline and at follow-up, 4, 8, and 12 weeks after treatment. Biopsies were examined for histological changes and immunohistochemically with CD3/CD8 and PD-L1. In addition, blood samples were examined for circulating cell-free DNA (cfDNA). Results A total of 10 procedures were performed and no serious adverse events occurred. Prior to inclusion, patients reported local symptoms, such as bleeding (N = 3), pain (N = 2), and stenosis (N = 5). Five of six patients reported symptom relief. In one patient, also receiving systemic chemotherapy, clinical complete response of primary tumor was seen. Immunohistochemistry found no significant changes in CD3 /CD8 levels or cfDNA levels after treatment. Conclusions This first study of calcium electroporation for colorectal tumors shows that calcium electroporation is a safe and feasible treatment modality for colorectal cancer. It can be performed as an outpatient treatment and may potentially be of great value for fragile patients with limited treatment options.

Risk factors for lymph node metastasis in patients with pT2 colon cancer in Denmark from 2016 to 2019-A nationwide cohort study.

AIM: The majority of patients with pT2 colon cancer have no lymph node metastasis (LNM). Knowledge of risk factors for LNM in pT2 colon cancer could identify patients at low risk and thereby potential candidates for local tumour excision. The aim of this work was to identify risk factors for LNM in pT2 colon cancer and describe a subgroup of low-risk patients. METHOD: This is a retrospective cohort study of patients with pT2 colon cancer from a nationwide Danish colorectal cancer database. Age, tumour size, location, histological type, mismatch repair protein status and venous, lymphatic and perineural invasion were included as potential risk factors in multivariate analysis. The primary outcome was LNM. RESULTS: We identified 1306 patients with pT2 colon cancer. LNM was present in 244 (19%). Demographic data were comparable in patients with and without LNM, and 864 patients who had complete histological data were included for multivariate analysis. Lymphatic (OR = 3.60, 95% CI 2.14-5.9), venous (OR = 1.70, 95% CI 1.03-2.74) and perineural (OR = 4.61, 95% CI 1.60-13.5) invasion were independent risk factors for LNM. Patients with deficient mismatch repair protein tumours had a decreased risk of LNM (OR = 0.55, 95% CI 0.31-0.95). Patients with clinical Stage I colon cancer and without risk factors had a 10.5% (47/443) risk of LNM. For patients with tumours with deficient mismatch repair protein status and no risk factors, the risk was 7.9%. CONCLUSION: Lymphatic, venous and perineural invasion are significant risk factors for LNM, and we identified a subgroup of patients with a low risk of LNM.

Preoperative prediction of lymph node status in patients with colorectal cancer. Developing a predictive model using machine learning.

PURPOSE: Develop a prediction model to determine the probability of no lymph node metastasis (pN0) in patients with colorectal cancer. METHODS: We used data from four Danish health databases on patients with colorectal cancer diagnosed between 2001 and 2019. The registries were harmonized into one common data model (CDM). Patients with clinical T4 tumors, undergoing palliative or acute surgery, and patients undergoing neoadjuvant therapy were excluded. Preoperative data was used to train the model. A postoperative model including tumor-specific variables potentially available after local tumor resection was also developed. Additionally, both models were compared with a model based on age, sex, and clinical N stage to resemble current standards. A Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression analysis for prediction was used. RESULTS: In total, 35,812 patients with 16,802 variables were identified in the CDM, and 194 variables affected the probability of pN0 preoperative. The area under the receiver operating characteristic curve (AUROC) was 0.64 (95% CI 0.63-0.66), and the area under the precision-recall curve (AUPRC) was 0.75 (95% CI 0.74-0.76). The mean predicted risk was 0.649, observed risk was 0.650, and calibration-in-large was 0.998. Adding histopathological data from the tumor improved the model slightly by increasing AUROC to 0.69. In comparison, the AUROC of the current standard clinical staging model was 0.57. CONCLUSION: Using Danish National Patient Registry data in a machine learning-based predictive model showed acceptable results and outperforms current tools for clinical staging in predicting pN0 status in patients scheduled for CRC surgery.

Tumor-Infiltrating Lymphocytes as Biomarkers of Treatment Response and Long-Term Survival in Patients with Rectal Cancer: A Systematic Review and Meta-Analysis.

Neoadjuvant chemoradiotherapy (NCRT) is indicated in locally advanced rectal cancer (LARC) to downstage tumors before surgery. Watchful waiting may be a treatment option to avoid surgery in patients, obtaining a complete clinical response. However, biomarkers predictive of treatment response and long-term prognosis are lacking. Here we investigated tumor-infiltrating lymphocytes (TILs) in pretherapeutic biopsies as predictive and prognostic biomarkers. A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. In total, 429 articles were identified, of which 19 studies were included in the systematic review and 14 studies in the meta-analysis. Patients with high pretherapeutic CD8+ TILs density had an increased likelihood of achieving a pathological complete response (RR = 2.71; 95% CI: 1.58-4.66) or a complete or near-complete pathological treatment response (RR = 1.86; 95% CI: 1.50-2.29). Furthermore, high CD8+ TILs density was a favorable prognostic factor for disease-free survival (HR = 0.57; 95% CI: 0.38-0.86) and overall survival (HR = 0.43; 95% CI: 0.27-0.69). CD3+, CD4+, and FOXP3+ TILs were not identified as predictive or prognostic biomarkers. Thus, assessing pretherapeutic CD8+ TILs density may assist in identifying patients with increased sensitivity to NCRT and favorable long-term prognosis.

Long-term oncological outcomes in patients undergoing laparoscopic versus open surgery for colon cancer: A nationwide cohort study.

AIM: To estimate the effect of laparoscopy versus laparotomy on recurrence status in patients undergoing intended curative resection for stage I-III colon cancer using nationwide data. METHOD: A retrospective cohort study using prospectively collected nationwide quality assurance data on all patients undergoing elective, intended curative surgery for UICC stage I-III colon cancer in Denmark from 1 January 2010, through 31 December 2013. The association between laparoscopic versus open surgery and recurrence status was investigated using cause-specific hazard and subdistribution hazard models with death from any cause as a competing event. RESULTS: In total, 4369 patients undergoing elective intended curative surgery for colon cancer were included in the analysis. Overall, 3243 (74.2%) patients underwent laparoscopic surgery. During a median follow-up time of 84 months, 1191 (27.2%) patients experienced recurrence, and 1304 (29.8%) patients died. The cause-specific hazard of recurrence following laparoscopic versus open surgery was HRCS  = 1.08, 95% CI: 0.90-1.28, p = 0.422. The subdistribution hazard of recurrence following laparoscopic versus open surgery was HRSD =0.99, 95% CI: 0.84-1.16, p = 0.880. CONCLUSION: Elective laparoscopic resection for UICC stage I-III colon cancer is oncologically safe and comparable with open resection. These results confirm the external validity of previous RCTs in everyday clinical settings.

The specificity of the malarial VAR2CSA protein for chondroitin sulfate depends on 4-O-sulfation and ligand accessibility.

Placental malaria infection is mediated by the binding of the malarial VAR2CSA protein to the placental glycosaminoglycan, chondroitin sulfate. Recombinant subfragments of VAR2CSA (rVAR2) have also been shown to bind specifically and with high affinity to cancer cells and tissues, suggesting the presence of a shared type of oncofetal chondroitin sulfate (ofCS) in the placenta and in tumors. However, the exact structure of ofCS and what determines the selective tropism of VAR2CSA remains poorly understood. In this study, ofCS was purified by affinity chromatography using rVAR2 and subjected to detailed structural analysis. We found high levels of N-acetylgalactosamine 4-O-sulfation (∼80-85%) in placenta- and tumor-derived ofCS. This level of 4-O-sulfation was also found in other tissues that do not support parasite sequestration, suggesting that VAR2CSA tropism is not exclusively determined by placenta- and tumor-specific sulfation. Here, we show that both placenta and tumors contain significantly more chondroitin sulfate moieties of higher molecular weight than other tissues. In line with this, CHPF and CHPF2, which encode proteins required for chondroitin polymerization, are significantly upregulated in most cancer types. CRISPR/Cas9 targeting of CHPF and CHPF2 in tumor cells reduced the average molecular weight of cell-surface chondroitin sulfate and resulted in a marked reduction of rVAR2 binding. Finally, utilizing a cell-based glycocalyx model, we showed that rVAR2 binding correlates with the length of the chondroitin sulfate chains in the cellular glycocalyx. These data demonstrate that the total amount and cellular accessibility of chondroitin sulfate chains impact rVAR2 binding and thus malaria infection.

The dynamic effects of preoperative intravenous iron in anaemic patients undergoing surgery for colorectal cancer.

AIM: The aim of this study was to describe the dynamic changes in blood work following individual adjusted dosage of intravenously administered iron(III) isomaltoside in a 4-week period prior to surgery in patients with colorectal cancer. METHODS: This was a single-centre, observational cohort study with prospectively collected data, including patients with colorectal cancer receiving preoperative treatment with iron(III) isomaltoside. Blood samples were taken at baseline, 1 week, 2 weeks and 4 weeks after initial treatment. Sixty-two patients were included in the study. RESULTS: Sixty-two patients were included for final analysis. The mean increase in haemoglobin was 0.77 g/dl (95% CI 0.52-1.03 g/dl, P < 0.0001) at week 1, 1.5 g/dl (95% CI 1.21-1.80 g/dl, P < 0.0001) at week 2 and 2.13 g/dl (95% CI 1.71-2.55 g/dl, P < 0.0001) at week 4. Patients with severe anaemia (<9.02 g/dl) showed the largest increase in haemoglobin during the treatment course (2.92 g/dl, 95% CI 2.27-3.58 g/dl, P < 0.0001). Patients with mild anaemia (>10.31 g/dl) did not show a significant increase (0.66 g/dl, 95% CI -0.29-1.61 g/dl, P = 0.17). The mean of transferrin saturation after 4 weeks was 8% (95% CI 6%-10%, P < 0.0001). CONCLUSIONS: After intravenously administered iron, patients with severe anaemia had the most substantial increase in haemoglobin, and the increase was largest after 4 weeks. Patients with mild anaemia did not have an increase in haemoglobin during the treatment course. The vast majority of patients still had iron deficiency at surgery 4 weeks after the initial treatment.