The impact of delayed commencement of adjuvant chemotherapy (eight or more weeks) on survival in stage II and III colon cancer: a national population-based cohort study

Abstract

BackgroundTo examine the impact of chemotherapy delay on survival in patients with stage II or III colon cancer and the factors associated with the delay (≥8 weeks) of adjuvant chemotherapy.MethodsPatients undergoing curative resection and adjuvant chemotherapy in a national population-based cohort were included.ResultsAmong 5355 patients, 154 (2.9%) received chemotherapy more than 8 weeks after surgery. Based on a multivariate analysis, the risk factors associated with chemotherapy delay ≥8 weeks were older age [65 to 74 years (hazard ratio [HR]=1.48) and ≥75 years (HR=1.69), p=0.0354], medical aid status in the health security system (HR=1.76, p=0.0345), and emergency surgery (HR=2.43, p=0.0002). Using an 8-week cutoff, the 3-year overall survival rate was 89.62% and 80.98% in the <8 weeks and ≥8 weeks groups, respectively (p=0.008). Independent prognostic factors for inferior overall survival included chemotherapy delay ≥8 weeks (HR=1.49, p=0.0365), older age [65 to 74 years (HR=1.94) and ≥75 years (HR=3.41), p<0.0001], TNM stage III (HR=2.46, p<0.0001), emergency surgery (HR=1.89, p<0.0001), American Society of Anesthesiologists score of 3 or higher (HR=1.50, p<0.0001), and higher transfusion amounts (HR=1.09, p=0.0392).ConclusionsThis study shows that delayed commencement of adjuvant chemotherapy, defined as ≥ 8 weeks, is associated with inferior overall survival in colon cancer patients with stage II or III disease. The delay to initiation of adjuvant chemotherapy is influenced by several multidimensional factors, including patient factors (older age), insurance status (medical aid), and treatment-related factors (emergency surgery).

Analysis of Prognostic Factors for Resected Synchronous and Metachronous Liver Metastases from Colorectal Cancer

“…Previously published papers reported improved outcomes after adjuvant chemotherapy without an increase in OS [ 10 , 31 ] confirming also that elderly patients are often oncologically undertreated [ 32 ]. Nevertheless, initiation of chemotherapy within 6–8 weeks is a recognized prognostic factor for OS [ 33 , 34 ]. Unfortunately, the small sample of patients receiving chemotherapy after surgery in this series precluded a subgroup analysis of the impact of the different chemotherapy regimens and use of molecular targeted therapies.…”

Localised colon cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

“…86 This observation has been confirmed by other groups. 87,88 However, population-based studies have shown that adjuvant chemotherapy might still provide some benefit, even with delays up to 5e6 months, 89,90 but it seems that the benefit of adjuvant chemotherapy is minimal or completely lost if treatment is started >6 months after surgery. pathological risk characteristics, patient comorbidity and risk assessment.…”

Management of cancer patients during COVID-19 pandemic at developing countries

“…Additionally, delaying some therapies with a curative intent may lead to adverse outcomes in cancer patients. A decrease in overall survival has been reported among patients with locally advanced breast cancer who had a delayed adjuvant or neoadjuvant chemotherapy[ 94 - 96 ], In stage II-III colon cancer, delaying adjuvant chemotherapy was also found to have a worse overall survival[ 97 , 98 ]. Similarly, delayed radiotherapy also has deleterious effects.…”