Treatment interval in curative treatment of colon cancer, does it impact (cancer free) survival? A non-inferiority analysis.

BACKGROUND: In treatment of colon cancer, strict waiting-time targets are enforced, leaving professionals no room to lengthen treatment intervals when advisable, for instance to optimise a patient's health status by means of prehabilitation. Good quality studies supporting these targets are lacking. With this study we aim to establish whether a prolonged treatment interval is associated with a clinically relevant deterioration in overall and cancer free survival. METHODS: This retrospective multicenter non-inferiority study includes all consecutive patients who underwent elective oncological resection of a biopsy-proven primary non-metastatic colon carcinoma between 2010 and 2016 in six hospitals in the Southern Netherlands. Treatment interval was defined as time between diagnosis and surgical treatment. Cut-off points for treatment interval were ≤35 days and ≤49 days. FINDINGS: 3376 patients were included. Cancer recurred in 505 patients (15.0%) For cancer free survival, a treatment interval >35 days and >49 days was non-inferior to a treatment interval ≤35 days. Results for overall survival were inconclusive, but no association was found. CONCLUSION: For cancer free survival, a prolonged treatment interval, even over 49 days, is non-inferior to the currently set waiting-time target of ≤35 days. Therefore, the waiting-time targets set as fundamental objective in current treatment guidelines should become directional instead of strict targets.

Node-negative colon cancer: histological, molecular, and stromal features predicting disease recurrence.

BACKGROUND: Within the group of node-negative colon cancer patients, presumed to have a good prognosis, a significant percentage of patients develops cancer-recurrence. Current high-risk features prove inadequate to select these particular high-risk patients. In the process of tailor-made care and shared decision-making the need to identify these patients grows. In this study we investigate the value of adding molecular markers and the tumour-stroma ratio (TSR) to conventional histological tumour staging methods to improve the selection of high risk patients. METHODS: We retrospectively analysed 201 patients diagnosed with TNM-stage I-II colon cancer and treated by complete oncological resection between November 1st 2002 and December 31st 2012 at the Jeroen Bosch Hospital. Conventional histological tumour staging, BRAF mutations, KRAS mutations, MSI status and TSR were determined. Differences between groups based on TSR and mutation status, in disease free survival were analysed using Cox-Regression analyses. RESULTS: Poorly differentiated histology (p = 0.002), high-TSR (p = 0.033), BRAF-mutation (p = 0.008) and MSI (p = 0.011) were identified as significant risk factors for cancer recurrence. The risk of recurrence increased in the presence of both a BRAF-mutation and high-TSR compared to the absence of both factors or presence of only one factor (HR = 3.66 BRAF-mt/TSR-low (p = 0.006), HR 2.82 BRAF-wt/TSR-high (p = 0.015), HR = 4.39 BRAF-mt/TSR-high (p = 0.023)). This was also seen in tumours with MSI and high-TSR (HR = 2.46 MSS/TSR-high (p = 0.041), HR = 3.31 MSI/TSR-high (p = 0.045). CONCLUSION: Judging by the higher HR for the combination of the prognostic factors TSR and BRAF compared to the HRs of these prognostic factors individually, the prognostication for disease free survival can be improved by determining both TSR and BRAF instead of BRAF alone, as is done in current daily practise. In this study MSI also shows additional value to TSR in the prognostication of disease free survival. Adopting TSR into daily diagnostics will be of additional value next to currently used molecular markers in risk stratification of patients with node negative colon cancer and is therefore advised.

Association of Heart Rate Variability with Pulmonary Function Impairment and Symptomatology Post-COVID-19 Hospitalization.

The persistence of symptoms beyond three months after COVID-19 infection, often referred to as post-COVID-19 condition (PCC), is commonly experienced. It is hypothesized that PCC results from autonomic dysfunction with decreased vagal nerve activity, which can be indexed by low heart rate variability (HRV). The aim of this study was to assess the association of HRV upon admission with pulmonary function impairment and the number of reported symptoms beyond three months after initial hospitalization for COVID-19 between February and December 2020. Follow-up took place three to five months after discharge and included pulmonary function tests and the assessment of persistent symptoms. HRV analysis was performed on one 10 s electrocardiogram obtained upon admission. Analyses were performed using multivariable and multinomial logistic regression models. Among 171 patients who received follow-up, and with an electrocardiogram at admission, decreased diffusion capacity of the lung for carbon monoxide (DLCO) (41%) was most frequently found. After a median of 119 days (IQR 101-141), 81% of the participants reported at least one symptom. HRV was not associated with pulmonary function impairment or persistent symptoms three to five months after hospitalization for COVID-19.

A high tumour-stroma ratio (TSR) in colon tumours and its metastatic lymph nodes predicts poor cancer-free survival and chemo resistance

PurposeDespite known high-risk features, accurate identification of patients at high risk of cancer recurrence in colon cancer remains a challenge. As tumour stroma plays an important role in tumour invasion and metastasis, the easy, low-cost and highly reproducible tumour-stroma ratio (TSR) could be a valuable prognostic marker, which is also believed to predict chemo resistance.MethodsTwo independent series of patients with colon cancer were selected. TSR was estimated by microscopic analysis of 4 µm haematoxylin and eosin (H&E) stained tissue sections of the primary tumour and the corresponding metastatic lymph nodes. Patients were categorized as TSR-low (≤ 50%) or TSR-high (> 50%). Differences in overall survival and cancer-free survival were analysed by Kaplan–Meier curves and cox-regression analyses. Analyses were conducted for TNM-stage I–II, TNM-stage III and patients with an indication for chemotherapy separately.ResultsWe found that high TSR was associated with poor cancer-free survival in TNM-stage I–II colon cancer in two independent series, independent of other known high-risk features. This association was also found in TNM-stage III tumours, with an additional prognostic value of TSR in lymph node metastasis to TSR in the primary tumour alone. In addition, high TSR was found to predict chemo resistance in patients receiving adjuvant chemotherapy after surgical resection of a TNM-stage II–III colon tumour.ConclusionIn colon cancer, the TSR of both primary tumour and lymph node metastasis adds significant prognostic value to current pathologic and clinical features used for the identification of patients at high risk of cancer recurrence, and also predicts chemo resistance.

Heart-rate-variability (HRV), predicts outcomes in COVID-19.

BACKGROUND: Patients with COVID-19 present with a variety of clinical manifestations, ranging from mild or asymptomatic disease to severe illness and death. Whilst previous studies have clarified these and several other aspects of COVID-19, one of the ongoing challenges regarding COVID-19 is to determine which patients are at risk of adverse outcomes of COVID-19 infection. It is hypothesized that this is the result of insufficient inhibition of the immune response, with the vagus nerve being an important neuro-immuno-modulator of inflammation. Vagus nerve activity can be non-invasively indexed by heart-rate-variability (HRV). Therefore, we aimed to assess the prognostic value of HRV, as a surrogate marker for vagus nerve activity, in predicting mortality and intensive care unit (ICU) referral, in patients hospitalized with COVID-19. METHODS: A retrospective cohort study including all consecutive patients (n = 271) diagnosed and hospitalized with COVID-19 between March 2020 and May 2020, without a history of cardiac arrhythmias (including atrial and ventricular premature contractions), pacemaker, or current bradycardia (heart rate <50 bpm) or tachycardia (heart rate >110 bpm). HRV was based on one 10s ECG recorded at admission. 3-week survival and ICU referral were examined. RESULTS: HRV indexed as standard deviation of normal to normal heartbeat intervals (SDNN) predicted survival (H.R. = 0.53 95%CI: 0.31-0.92). This protective role was observed only in patients aged 70 years and older, not in younger patients. HRV below median value also predicted ICU referral within the first week of hospitalization (H.R = 0.51, 95%CI: 0.29-0.90, P = 0.021). CONCLUSION: Higher HRV predicts greater chances of survival, especially in patients aged 70 years and older with COVID-19, independent of major prognostic factors. Low HRV predicts ICU indication and admission in the first week after hospitalization.

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.

Impact of therapeutic delay in colorectal cancer on overall survival and cancer recurrence - is there a safe timeframe for prehabilitation?

INTRODUCTION: Interest in adoption of a prehabilitation programme in management of colorectal cancer is increasing, but current waiting time targets leave no opening for intervention. Prompt treatment following diagnosis is demanded but defending evidence is lacking. We aimed to investigate the impact of prolonged therapeutic delay on overall and cancer-free survival in patients with primary colorectal cancer. METHODS: Retrospective analysis was performed in a detailed dataset of patients with primary colorectal cancer who underwent curative surgical treatment between January 2010 and December 2016. Groups were made according to therapeutic delay ≤35 days or >35 days. Endpoints were overall and cancer-free survival, assessed with Kaplan-Meier survival curves, log-rank tests and Cox proportional hazard analyses. RESULTS: A total of 790 patients were included of whom 559 had a colonic tumour and 231 a rectal tumour. Median therapeutic delay was 32 days (IQR 26-43 days). Multivariate analysis showed therapeutic delay >35 days was not associated with poorer overall survival (HR = 1.202, p = 0.249) or earlier cancer recurrence (HR = 1.256, p = 0.212). Similar results were found when stratifying analyses for colonic and rectal cancer, and when defining prolonged delay as >49 days. CONCLUSION: Prolonged treatment delay does not lead to poorer overall or cancer-free survival in patients with primary colorectal cancer who underwent curative surgical treatment. This allows professionals to push current national waiting time targets in order to adopt a prehabilitation programme without jeopardizing outcomes.