Transanal TME Proves Noninferior to Laparoscopic Approach in 3-Year Disease-Free Survival for Rectal Cancer: TaLaR Trial

Previous studies have highlighted the benefits of transanal total mesorectal excision over laparoscopic TME, particularly in terms of short-term histopathological outcomes and complications. However, the long-term oncological efficacy of transanal TME remains uncertain. Addressing this gap, Ziwei Zeng, Sun Yat-sen University, Guangzhou, Guangdong, China, and colleagues aimed to evaluate and compare the 3-year disease-free survival rates between transanal TME and laparoscopic TME in patients with rectal cancer.

For this purpose, the researchers conducted a randomized, open-label, noninferiority phase 3 clinical trial across 16 centers in China. Between April 2016 and June 2021, they enrolled 1,115 patients with clinical stage I to III mid-low rectal cancer. Participants were randomly assigned in a 1:1 ratio to undergo either transanal TME (n = 558) or laparoscopic TME (n = 557) before their surgical procedures.

The study's primary endpoint was 3-year disease-free survival, with a noninferiority margin set at −10% for comparing transanal TME to laparoscopic TME. Secondary outcomes included 3-year overall survival and local recurrence rates. The final participant follow-up was completed in June 2024.

The following were the key findings of the study:

• The median age of patients in the primary analysis set was 60 years, with 692 males and 397 females included.
• The 3-year disease-free survival was 82.1% for the transanal TME group and 79.4% for the laparoscopic TME group, showing a difference of 2.7%.
• The lower limit of the 97.5% confidence interval for the group difference in 3-year disease-free survival was above the noninferiority margin of −10 percentage points.
• The 3-year local recurrence rate was 3.6% for transanal TME and 4.4% for laparoscopic TME.
• The 3-year overall survival was 92.6% for transanal TME and 90.7% for laparoscopic TME.

In conclusion, the study assessed the 3-year disease-free survival in patients with rectal cancer who underwent either transanal TME or laparoscopic TME.

"The findings suggest that transanal TME offers noninferior 3-year disease-free survival compared to laparoscopic TME. Additionally, the trial demonstrated comparable 3-year overall survival and local recurrence rates between patients treated with transanal TME and those treated with laparoscopic TME. These results emphasize the viability of transanal TME as an effective alternative to laparoscopic TME in rectal cancer treatment," the researchers wrote.

Reference:

Zeng Z, Luo S, Zhang H, et al. Transanal vs Laparoscopic Total Mesorectal Excision and 3-Year Disease-Free Survival in Rectal Cancer: The TaLaR Randomized Clinical Trial. JAMA. Published online January 23, 2025. doi:10.1001/jama.2024.24276