Watch-and-wait approach feasible for rectal cancer patients responding to neoadjuvant therapy

Survival outcomes do not differ between patients with locally advanced rectal cancer treated with mandatory total mesorectal excision (TME) and those on selective watch-and-wait (WW) strategies following total neoadjuvant therapy (TNT), reports a study.

Researchers performed a pooled analysis of the CAO/ARO/AIO-12 (n=304) and OPRA (n=324) trials, which randomized patients with stage II/III rectal cancer to receive either induction or consolidation chemotherapy as part of TNT.

Participants in the CAO/ARO/AIO-12 trial underwent TME within 6 weeks of TNT completion. In the OPRA trial, patients with complete or near-complete response were allowed to enter WW, while those with an incomplete response proceeded to TME.

Disease-free survival (DFS) was the primary endpoint of the pooled analysis. Other outcomes assessed were distant recurrence-free survival (DRFS), local recurrence-free survival (LRFS), and overall survival (OS). Median follow-up was 3.6 years for CAO/ARO/AIO-12 and 5.1 years for OPRA.

Patients in the CAO/ARO/AIO-12 trial were more likely to present with cT3/4 and cN-positive disease, while those in the OPRA trial had tumours closer to the anal verge. Compliance to TNT and the rate of grade 3+ adverse events did not significantly differ between the two studies.

The pooled analysis revealed no difference in survival outcomes (ie, DFS, DRF, LRFS, or OS) based on treatment strategy or TNT treatment arm.

“These results strengthen available evidence indicating that WW is a safe treatment option for patients with an excellent response to neoadjuvant therapy,” the researchers said.