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The following is a summary of “Short- and long-term outcomes of neoadjuvant chemotherapy compared with neoadjuvant chemoradiotherapy for locally advanced rectal cancer: an updated meta-analysis,” published in the February 2025 issue of the BMC Gastroenterology by Guo et al.

Neoadjuvant chemoradiotherapy (NACRT) has long been the standard treatment for locally advanced rectal cancer (LARC), offering tumor downstaging benefits but also posing risks of radiation-induced toxicity. With the development of more optimized chemotherapy regimens, neoadjuvant chemotherapy (NAC) has emerged as a potential alternative, aiming to achieve similar oncologic outcomes while reducing radiation-associated side effects. This meta-analysis was conducted to comprehensively compare the short- and long-term outcomes of NAC versus NACRT in patients with LARC.

A systematic literature search was performed across multiple online databases to identify relevant studies published up to June 15, 2023. Data from 10 eligible studies, encompassing a total of 14,807 patients (NAC: 1,714; NACRT: 13,093), were analyzed. Outcomes of interest included short-term measures such as pathological complete response (pCR), tumor regression grade (TRG), sphincter preservation rate, and adverse events, as well as long-term oncologic outcomes including local recurrence, disease-free survival, and overall survival.

The analysis revealed no significant differences between NAC and NACRT in terms of lymphovascular invasion, perineural invasion, R0 resection rates, local recurrence, OS, DFS, or grade 3–4 adverse events, indicating comparable overall oncologic efficacy. However, NAC was associated with a lower pCR rate (OR: 0.61; 95% CI: 0.45–0.82) and reduced tumor regression (OR: 0.42; 95% CI: 0.25–0.70) compared to NACRT. Conversely, NAC demonstrated a higher rate of sphincter preservation (OR: 1.57; 95% CI: 1.14–2.16), suggesting a potential advantage in functional outcomes. Notably, in prospective studies, no statistically significant differences were observed between the two groups regarding pCR (OR: 0.62; 95% CI: 0.35–1.11), TRG (OR: 0.72; 95% CI: 0.52–1.00), or sphincter preservation rate (OR: 1.40; 95% CI: 0.94–2.09), further supporting the feasibility of NAC as an alternative to NACRT.

These findings suggest that NAC may achieve comparable short- and long-term outcomes to NACRT while offering the advantage of reducing radiation exposure and increasing the likelihood of sphincter preservation. However, it is important to note that some prospective studies excluded patients with high-risk features, which could influence the generalizability of the results. Further research, particularly large-scale, prospective clinical trials, is required to clarify the efficacy of NAC in patients with high-risk LARC features and to establish more refined selection criteria for its application in clinical practice.

Source: bmcgastro321`wqenterol.biomedcentral.com/articles/10.1186/s12876-025-03667-8