Is there a role for total neoadjuvant treatment in early-stage rectal cancer?

Current guidelines recommend surgical interventions for stage I rectal cancer (S1RC). Impaired functions and permanent colostomy remain undesirable outcomes, particularly in low-located stage I rectal cancer. Selective use of total neoadjuvant treatment (TNT) in S1RC may be a potential treatment option.

Patients with S1RC who declined total mesorectal excision (TME) and opted for TNT between 2015 and 2023 were retrospectively reviewed. The study included two groups: (1) patients with S1RC who demonstrated a partial response following chemoradiation and chose consolidation chemotherapy, and (2) patients who underwent local excision of rectal lesions that were subsequently confirmed as S1RC but declined the recommended TME. Primary outcomes were complete response and organ preservation rates.

The study included sixteen S1RC patient (69% male) who underwent TNT. Eleven patients received TNT following partial response, while the remaining underwent TNT after transanal full-thickness local excision. In the first group (n = 11), nine patients achieved a complete clinical response. One patient with a near-complete response underwent endoscopic submucosal dissection, which revealed a tubulovillous adenoma. Another patient demonstrated a partial clinical response and subsequently underwent low anterior resection, with the final pathology showing a complete response. In patients who received TNT after local excisions, no local recurrence or distant metastasis was observed, with a median follow-up of 20 months (IQR 12). The overall complete response rate following TNT is 93.7%, and organ preservation rate of the study was 87.5%.

Selective utilization of TNT in S1RC holds the potential to foster organ preservation, particularly for low rectal cancer. Larger prospective studies with longer follow-up and standardized treatment protocols are needed to validate these preliminary findings.