Survival of surgical and non-surgical older patients with non-metastatic colorectal cancer: A population-based study in the Netherlands

Abstract

BACKGROUND: Surgery is the primary treatment for non-metastatic colorectal cancer (CRC) but is omitted in a proportion of older patients. Characteristics and prognosis of non-surgical patients are largely unknown. OBJECTIVE: To examine the characteristics and survival of surgical and non-surgical older patients with non-metastatic CRC in the Netherlands. METHODS: All patients aged ≥70 years and diagnosed with non-metastatic CRC between 2014 and 2018 were identified in the Netherlands Cancer Registry. Patients were divided based on whether they underwent surgery or not. Three-year overall survival (OS) and relative survival (RS) were calculated for both groups separately. Relative survival and relative excess risks (RER) of death were used as measures for cancer-related survival. RESULTS: In total, 987/20.423 (5%) colon cancer patients and 1.459/7.335 (20%) rectal cancer patients did not undergo surgery. Non-surgical treatment increased over time from 3.7% in 2014 to 4.8% in 2018 in colon cancer patients (P = 0.01) and from 17.1% to 20.2% in rectal cancer patients (P = 0.03). 3 year RS was 91% and 9% for surgical and non-surgical patients with colon cancer, respectively. For rectal cancer patients this was 93% and 37%, respectively. In surgical patients, advanced age (≥80 years) did not decrease RS (colon; RER 0.9 (0.7-1.0), rectum; RER 0.9 (0.7-1.1)). In non-surgical rectal cancer patients, higher survival rates were observed in patients treated with chemoradiotherapy (OS 56%, RS 65%), or radiotherapy (OS 19%, RS 27%), compared to no treatment (OS 9%, RS 10%). CONCLUSION: Non-surgical treatment in older Dutch CRC patients has increased over time. Because survival of patients with colon cancer is very poor in the absence of surgery, this treatment decision must be carefully weighed. (Chemo-)radiotherapy may be a good alternative for rectal cancer surgery in older frail patients.