In a Dutch nationwide cross-sectional cohort study reported in JAMA Oncology, Hazen et al found that a reduced use of neoadjuvant radiotherapy as part of chemoradiotherapy was not associated with poorer outcomes in patients with non–locally advanced rectal cancer.
As stated by the investigators, “Neoadjuvant short-course radiotherapy was routinely applied for non–locally advanced rectal cancer (cT1-3N0-1M0 with > 1 mm distance to the mesorectal fascia) in the Netherlands following the Dutch total mesorectal excision trial. This policy has shifted toward selective application after guideline revision in 2014.”
Study Details
The study involved data from two cohorts of patients with surgically treated rectal cancer: one contained patients treated in 2011, with follow-up through 2015; the other contained patients treated in 2016, with follow-up through 2021. From these cohorts, all patients with cT1-3N0-1M0 disease and radiologically unthreatened mesorectal fascia were included in the current analysis, including 1,199 eligible patients in the 2011 cohort and 1,576 in the 2016 cohort. The main outcome measures were 4-year local recurrence and overall survival.
Key Findings
The use of neoadjuvant radiotherapy decreased from 87% in the 2011 cohort to 37% in the 2016 cohort. Local recurrence rates at 4 years were 5.8% in the 2011 cohort vs 5.5% in the 2016 cohort (P = .99); distant recurrence rates were 19.5% vs 16.8% (P = .11)
Overall survival rates at 4 years were 79.6% in the 2011 cohort vs 86.4% in the 2016 cohort (P < .001). Cancer-related mortality rates were 7.6% vs 8.0% (P = .74), non–cancer-related mortality rates were 13.8% vs 6.3% (P < .001). Disease-free survival rates at 4 years were 67.5% vs 75.7% (P < .001).
The investigators concluded, “The results of this cross-sectional study suggest that an absolute 50% reduction in radiotherapy use for non–locally advanced rectal cancer did not compromise cancer-related outcomes at a national level. Optimizing clinical staging and surgery following the Dutch total mesorectal excision trial has potentially enabled safe deintensification of treatment.”
Miranda Kusters, MD, PhD, of Amsterdam UMC Vrije Universiteit Amsterdam, is the corresponding author for the JAMA Oncology article.
Disclosure: The study was supported by the Dutch Cancer Society. For full disclosures of the study authors, visit jamanetwork.com.
