1164P - The influence of neoadjuvant radiotherapy on surgical management and prognostic outcomes in locally advanced rectal neuroendocrine carcinoma

Background

The standard approach for managing locally advanced rectal cancer includes preoperative neoadjuvant chemoradiotherapy followed by curative surgery, a regimen acknowledged for substantially enhancing local control rates. Nevertheless, the benefits of perioperative radiotherapy in treating rectal neuroendocrine carcinoma merit further investigation. This study explores the impact of preoperative neoadjuvant radiotherapy on the feasibility of sphincter-preserving surgery and on the overall survival rates in patients with locally advanced rectal neuroendocrine carcinoma.

Methods

Data from patients diagnosed with locally advanced (T3/T4 or N+) neuroendocrine carcinoma who underwent curative surgery from 2004 to 2019 were collected using the SEER database. We assessed clinical characteristics, treatment information, and overall survival rates. Statistical comparisons of categorical variables were performed using the Chi-square test or Fisher's exact test. Survival outcomes were analyzed using the Kaplan-Meier method.

Results

Of the 44 patients identified, 14 underwent preoperative neoadjuvant radiotherapy. Patients with a T-stage above T3 (42.9% vs. 12.5%, P = 0.049) and those without lymph node metastasis (87.5% vs. 19.4%, P < 0.001) were more likely to receive perioperative radiotherapy. The probability of performing sphincter-preserving surgery was notably lower in patients treated with neoadjuvant radiotherapy (57.1% vs. 93.3%, P = 0.008). Additionally, survival analysis indicated no significant relationship between neoadjuvant radiotherapy and overall survival (HR 1.298,95% CI:0.519-3. 244, P =0. 577).

Conclusions

Neoadjuvant radiotherapy prior to surgery did not improve the likelihood of performing sphincter-preserving procedures in patients with locally advanced rectal neuroendocrine carcinoma, nor did it significantly impact overall survival. Further research involving larger sample sizes is required to confirm these findings.

Clinical trial identification

Editorial acknowledgement

During the preparation of this work, the author(s) used ChatGPT for editorial assistance in order to optimize content expression. After using this tool, the author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the publication.

Legal entity responsible for the study

W. Xu.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.