Anterior tumour location as a risk factor for local recurrence after laparoscopic surgery for stage I ultra-low rectal cancers: exploratory analysis of the Ultimate trial
In brief
Anterior tumors had 12% three-year local recurrence after laparoscopic surgery
In an exploratory analysis of 297 patients with stage I ultra-low rectal cancer, local recurrence by three years was 11.9% for anterior tumors versus 3.0% for other locations. The difference was concentrated in cT2 tumors, while overall and recurrence-free survival were similar; whether a different treatment or closer monitoring improves outcomes remains unknown.
- Journal
- BJS open (Q1)
- Published
- 4 September 2026
- Study design
- Non-randomized / quasi-experimental trial
- Evidence level
- Level 2, Moderate (CEBM 2b)
- Authors
- Atsushi Kohyama, Shinobu Ohnuma, Yuichiro Tsukada, Michiaki Unno, Jun Watanabe, Yosuke Fukunaga, et al.
- PMID
- 42814593
- DOI
- 10.1093/bjsopen/zrag128
Why clinicians should know about it
- Picked for Gastrointestinal and Colorectal Surgery (paper of the day, 4 October 2026): Anterior tumour location linked to higher local recurrence
Abstract
BACKGROUND: Anterior tumour location is an established risk factor for local recurrence (LR) in advanced rectal cancer, but its significance in stage I ultra-low rectal cancer remains unclear. METHODS: This exploratory supplemental analysis used data from Ultimate trial, a multicentre prospective phase II study across 47 Japanese institutions (2014-2017). Patients with cT1-2 N0 M0 ultra-low rectal cancer (≤ 5 cm from the anal verge) underwent laparoscopic resection. Tumour location was categorized as anterior (10-2 o'clock) or non-anterior (2-10 o'clock). The primary endpoint was LR; secondary endpoints included recurrence-free survival, overall survival, and stoma-free survival. RESULTS: Of 300 enrolled patients, 297 were analysed (median follow-up 37.2 months); 93 tumours (31.3%) were anterior. Baseline characteristics, operative outcomes, and pathological findings were similar between the two groups. The 3-year cumulative LR rate was 11.9% for anterior tumours and 3.0% for non-anterior tumours (hazard ratio (HR) 4.46; 95% confidence interval (c.i.) 1.67 to 11.89; P = 0.001). Multivariable analysis showed an independent association between anterior location and LR (HR 4.68; 95% c.i. 1.72 to 12.74); subgroup analysis revealed no difference in clinical (c) T1 patients, but a significantly higher LR rate for anterior tumours in cT2 patients (25.3% versus 4.7%; P < 0.001). Three-year recurrence-free survival (83.9% for anterior tumours versus 88.9% for non-anterior tumours; P = 0.222), overall survival (> 95%), and stoma-free survival were comparable between the two groups. CONCLUSION: Anterior tumour location in the ultra-low rectum was associated with an increased risk of LR, particularly in cT2 patients, highlighting the need for a more refined treatment strategy and vigilant monitoring.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.