Impact of Hospital Volume on Local Recurrence of Rectal Cancer After Transanal Total Mesorectal Excision: A Nationwide Multicenter Cohort Study in Japan
摘要
Concerns have been raised regarding the risk of local recurrence (LR) following transanal total mesorectal excision (TaTME), particularly during the learning curve. This study aimed to evaluate the impact of hospital case volume on LR after TaTME in Japan.
Patients and MethodsThis multicenter retrospective cohort study included 710 patients who underwent TaTME for rectal cancer at 25 institutions between 2014 and 2019. Hospitals were categorized as low volume (1–38 cases) or high volume (≥ 39 cases). The primary outcome was 5-year local recurrence rate (LRR). Multivariable Cox regression was performed to identify risk factors for LR.
ResultsOf 710 patients, 277 were treated in low-volume hospitals and 433 in high-volume hospitals. The median follow-up was 46 months. Cumulative incidence of LR was significantly different (P = 0.048), and 5-year LRR was higher in the low-volume than in the high-volume groups (12.9% versus 6.8%). Multifocal LR was also more frequent in low-volume centers (4.1% versus 1.2%, P = 0.041). In multivariable analysis, treatment in low-volume hospitals was an independent predictor of LR (hazard ratio 2.15, 95% CI 1.25–3.69; P < 0.01). Subgroup analysis revealed increased LR in low-volume centers for patients undergoing anterior resection with the single stapling technique and for those with pT3/4 disease, nodal metastasis, or pathological lateral lymph node involvement.
ConclusionsHospital case volume was independently associated with LR after TaTME. Although increased recurrence was observed in low-volume centers, particularly among certain subgroups, the volume effect likely reflects multifactorial institutional influences rather than technical aspects alone.