Overall survival of patients with colon cancer and a prolonged time to surgery

The effect of time before diagnosis and treatment on colorectal cancer outcomes: systematic review and dose-response meta-analysis

BACKGROUND

This systematic review and meta-analysis aimed to evaluate existing evidence on the relationship between diagnostic and treatment intervals and outcomes for colorectal cancer.

METHODS

Four databases were searched for English language articles assessing the role of time before initial treatment in colorectal cancer on any outcome, including stage and survival. Two reviewers independently screened articles for inclusion and data were synthesised narratively. A dose-response meta-analysis was performed to examine the association between treatment interval and survival.

RESULTS

One hundred and thirty papers were included in the systematic review, eight were included in the meta-analysis. Forty-five different intervals were considered in the time from first symptom to treatment. The most common finding was of no association between the length of intervals on any outcome. The dose-response meta-analysis showed a U-shaped association between the treatment interval and overall survival with the nadir at 45 days.

CONCLUSION

The review found inconsistent, but mostly a lack of, association between interval length and colorectal cancer outcomes, but study design and quality were heterogeneous. Meta-analysis suggests survival becomes increasingly poorer for those commencing treatment more than 45 days after diagnosis.

REGISTRATION

This review was registered, and the protocol is available, in PROSPERO, the international database of systematic reviews, with the registration ID CRD42021255864.

The impact of time to surgery on oncological outcomes in stage I-III dMMR colon cancer - A nationwide cohort study

INTRODUCTION

One of the considerations when investigating neoadjuvant interventions is the prolonging of time from diagnosis to curative surgery (i.e. the treatment interval [TI]). The aim of this study was to investigate the association between the length of TI and overall survival and disease-free survival in patients with deficient mismatch repair (dMMR) colon cancer.

MATERIALS AND METHODS

This retrospective propensity score-adjusted study included all patients of ≥18 years of age undergoing elective curative surgery for stage I-III, dMMR colon cancer. Data were extracted from four Danish patient databases. Outcomes were investigated in groups with TIs of ≤14 days versus >14 days. Propensity scores were computed using all demographics, diagnoses and measurements. Matching was done in a 1:1 ratio.

RESULTS

A total of 4130 patients were included in the study with a mean age of 73.8 years and a median follow-up time of 43.9 months. After matching, 2794 patients were included in the analysis of overall survival. No significant difference in overall survival was seen between patients with TIs of ≤14 days versus >14 days (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.81-1.17; p = 0.78). In the analysis of disease-free survival, 1798 patients were included after matching. This showed no significant difference between patients with TIs of ≤14 days versus >14 days (HR, 0.85; 95% CI, 0.69-1.06; p = 0.14).

CONCLUSION

No associations were found between TI and overall survival and disease-free survival in patients with stage I-III, dMMR colon cancer undergoing elective curative surgery.

A systematic review of methodological considerations in time to diagnosis and treatment in colorectal cancer research

Research focusing on timely diagnosis and treatment of colorectal cancer is necessary to improve outcomes for people with cancer. Previous attempts to consolidate research on time to diagnosis and treatment have noted varied methodological approaches and quality, limiting the comparability of findings. This systematic review was conducted to comprehensively assess the scope of methodological issues in this field and provide recommendations for future research. Eligible articles had to assess the role of any interval up to treatment, on any outcome in colorectal cancer, in English, with no limits on publication time. Four databases were searched (Ovid Medline, EMBASE, EMCARE and PsycInfo). Papers were screened by two independent reviewers using a two-stage process of title and abstract followed by full text review. In total, 130 papers were included and had data extracted on specific methodological and statistical features. Several methodological problems were identified across the evidence base. Common issues included arbitrary categorisation of intervals (n = 107, 83%), no adjustment for potential confounders (n = 65, 50%), and lack of justification for included covariates where there was adjustment (n = 40 of 65 papers that performed an adjusted analysis, 62%). Many articles introduced epidemiological biases such as immortal time bias (n = 37 of 80 papers that used survival as an outcome, 46%) and confounding by indication (n = 73, 56%), as well as other biases arising from inclusion of factors outside of their temporal sequence. However, determination of the full extent of these problems was hampered by insufficient reporting. Recommendations include avoiding artificial categorisation of intervals, ensuring bias has not been introduced due to out-of-sequence use of key events and increased use of theoretical frameworks to detect and reduce bias. The development of reporting guidelines and domain-specific risk of bias tools may aid in ensuring future research can reliably contribute to recommendations regarding optimal timing and strengthen the evidence base.

The Impact of Surgical Delays on Short- and Long-Term Survival Among Colon Cancer Patients

BACKGROUND

The purpose of this study was to assess the impact of surgical delays on short- and long-term survival among colon cancer patients.

METHODS

Adult patients undergoing surgery for stage I, II, or III colon cancer were identified from the National Cancer Database (2010-2016). After categorization by wait times from diagnosis to surgery (<1 week, 1-3 weeks, 3-6 weeks, 6-9 weeks, 9-12 weeks, and >12 weeks), 30-day mortality, 90-day mortality, and 5-year overall survival were compared between patients both overall and after stratification by pathological disease stage.

RESULTS

Among 187 394 colon cancer patients, 24.2% waited <1 week, 30.5% waited 1-3 weeks, 29.0% waited 3-6 weeks, 9.7% waited 6-9 weeks, 3.3% waited 9-12 weeks, and 3.3% waited >12 weeks for surgery. Patients undergoing surgery 3-6 weeks after colon cancer diagnosis exhibited the best 30-day mortality (1.3%), 90-day mortality (2.3%), and 5-year overall survival (71.8%) (P < .001 for all). After risk-adjusting for confounders, all wait times beyond 6 weeks were associated with worse 5-year overall survival (6-9 weeks: HR 1.10, 95% CI 1.06-1.15; 9-12 weeks: HR 1.25, 95% CI 1.18-1.33; >12 weeks: HR 1.43, 95% CI 1.35-1.52; P < .001 for all). Subgroup analysis after stratification by disease stage demonstrated that patients with stage III colon cancer were able to wait up to 9 weeks before exhibiting worse 5-year overall survival, compared to 6 weeks for patients with stage I or II disease.

CONCLUSIONS

Colon cancer patients should undergo surgery 3-6 weeks after diagnosis, as all surgical delays beyond 6 weeks were associated with worse 30-day mortality, 90-day mortality, and 5-year overall survival.

The Association Between Treatment Interval and Survival in Patients With Colon or Rectal Cancer: A Systematic Review

BACKGROUND

Surgery for colon or rectal cancer is associated with a high incidence of complications, especially in patients with a low aerobic fitness. Those patients might benefit from a comprehensive preoperative workup including prehabilitation. However, time between diagnosis and treatment is often limited due to current treatment guidelines. To date, it is unclear whether the treatment interval can be extended without compromising survival.

METHODS

A systematic review concerning the association between treatment intervals and survival in patients who underwent elective curative surgery for colon or rectal cancer was performed. A search up to December 2020 was conducted in PubMed, Cinahl and Embase. Original research articles were eligible. Quality assessment was performed using the Downs and Black checklist.

RESULTS

Eleven observational studies were included (897 947 patients). In colon cancer, treatment intervals that were statistically significant associated with reduced overall survival or cancer-specific survival ranged between > 30 and > 84 days. In rectal cancer, only one out of four studies showed that treatment intervals > 49 days was associated with reduced cancer-specific survival.

CONCLUSIONS

This systematic review identified that studies investigating the association between treatment intervals and survival are heterogeneous with regard to treatment interval definitions, treatment interval time intervals and used outcome measures. These aspects need standardization before a reliable estimate of an optimal treatment interval can be made. In addition, further research should focus on establishing optimal treatment intervals in patients at high risk for postoperative complications, as particularly these patients might benefit from extended diagnosis to treatment intervals permitting comprehensive preoperative preparation.

Verticillin A inhibits colon cancer cell migration and invasion by targeting c-Met

Verticillin A is a diketopiperazine compound which was previously isolated from Amanita flavorubescens Alk (containing parasitic fungi Hypomyces hyalines (Schw.) Tul.). Here, we initially found, by wound healing assay and Transwell assay in vitro, that verticillin A possesses an inhibitory effect against the migration and invasion of the human colon cancer cell. Subsequently, c-mesenchymal-epithelial transition factor (c-Met) was identified as a molecular target of verticillin A by screening key genes related to cell migration. Verticillin A-mediated c-Met suppression is at the transcriptional level. Further study demonstrated that verticillin A suppressed c-MET phosphorylation and decreased c-MET protein level. In addition, verticillin A inhibited the phosphorylation of c-MET downstream molecules including rat sarcoma (Ras)-associated factor (Raf), extracellular signal-regulated kinase (ERK), and protein kinase B (AKT). Overexpression of Erk partially reversed the verticillin A-mediated anti-metastasis action in the human colon cancer cell. More importantly, verticillin A also inhibited cancer cell metastasis in vivo. Thus, verticillin A can significantly inhibit the migration and invasion of colon cancer cells by targeting c-Met and inhibiting Ras/Raf/mitogen-activated extracellular signal-regulated kinase (MEK)/ERK signaling pathways. Therefore, we determined that verticillin A is a natural compound that can be further developed as an anti-metastatic drug in human cancers.

BVES-AS1 inhibits the malignant behaviors of colon adenocarcinoma cells via regulating BVES

The underexpression of the long noncoding RNA blood vessel epicardial substance antisense RNA 1 (BVES-AS1) has been shown in colon adenocarcinoma (COAD) patients. However, its role in COAD remains to be explored. This study aimed to investigate the function and potential mechanism of BVES-AS1 in COAD. Colony formation, Cell Counting Kit-8, JC-1 mitochondrial membrane potential assay, wound healing, transwell, and western blot analyses were used to measure cell proliferation, apoptosis, migration, invasion, and epithelial-mesenchymal transition (EMT) in COAD cells. RNA pull-down, luciferase reporter, and RNA binding protein immunoprecipitation assays were used to detect the interaction of BVES-AS1 and downstream genes. BVES-AS1 was expressed at low levels in COAD cells. Overexpressed BVES-AS1 inhibited COAD cell proliferation, migration, invasion, and EMT while elevating cell apoptosis. Mechanistically, BVES-AS1 functioned as a competing endogenous RNA sponging miR-522-3p to regulate the expression of nearby gene blood vessel epicardial substance (BVES). Besides this, BVES-AS1 recruited TATA-box binding protein associated factor 15 (TAF15) to promote BVES messenger RNA stability. Taken together, our study confirmed that BVES-AS1 inhibited COAD progression via interacting with miR-522-3p and TAF15 to regulate BVES expression, which might offer a perspective for COAD treatment.

Conflicting Guidelines: A Systematic Review on the Proper Interval for Colorectal Cancer Treatment

BACKGROUND

Timely treatment for colorectal cancer (CRC) is a quality indicator in oncological care. However, patients with CRC might benefit more from preoperative optimization rather than rapid treatment initiation. The objectives of this study are (1) to determine the definition of the CRC treatment interval, (2) to study international recommendations regarding this interval and (3) to study whether length of the interval is associated with outcome.

METHODS

We performed a systematic search of the literature in June 2020 through MEDLINE, EMBASE and Cochrane databases, complemented with a web search and a survey among colorectal surgeons worldwide. Full-text papers including subjects with CRC and a description of the treatment interval were included.

RESULTS

Definition of the treatment interval varies widely in published studies, especially due to different starting points of the interval. Date of diagnosis is often used as start of the interval, determined with date of pathological confirmation. The end of the interval is rather consistently determined with date of initiation of any primary treatment. Recommendations on the timeline of the treatment interval range between and within countries from two weeks between decision to treat and surgery, to treatment within seven weeks after pathological diagnosis. Finally, there is no decisive evidence that a longer treatment interval is associated with worse outcome.

CONCLUSIONS

The interval from diagnosis to treatment for CRC treatment could be used for prehabilitation to benefit patient recovery. It may be that this strategy is more beneficial than urgently proceeding with treatment.

Gastrointestinal Malignancies and the COVID-19 Pandemic: Evidence-Based Triage to Surgery

BACKGROUND

The COVID-19 pandemic has led to widespread cancelation of electively scheduled surgeries, including for colorectal, pancreatic, and gastric cancer. The American College of Surgeons and the Society of Surgical Oncology have released guidelines for triage of these procedures. We seek to synthesize available evidence on delayed resection and oncologic outcomes, while also providing a critical assessment of the released guidelines.

METHODS

A systematic review was conducted to identify literature between 2005 and 2020 investigating the impact of time to surgery on oncologic outcomes in colorectal, pancreatic, and gastric cancer.

RESULTS

For colorectal cancer, 1066 abstracts were screened and 43 papers were included. In primarily resected colon cancer, delay over 30 to 40 days is associated with lower survival. In rectal cancer, time to surgery over 7 to 8 weeks following neoadjuvant therapy is associated with decreased survival. Three hundred ninety-four abstracts were screened for pancreatic cancer and nine studies were included. Two studies demonstrate increased unexpected progression with delayed surgery over 30 days. Out of 633 abstracts screened for gastric cancer, six studies were included. No identified study demonstrated worse survival with increased time to surgery.

CONCLUSION

Moderate evidence suggests that delayed resection of colorectal cancer worsens survival; the impact of time to surgery on gastric and pancreatic cancer outcomes is uncertain. Early resection of gastrointestinal malignancies provides the best chance for curative therapy. During the COVID-19 pandemic, prioritization of procedures should account for available evidence on time to surgery and oncologic outcomes.