Local excision for middle-low rectal cancer after neoadjuvant chemoradiation: A retrospective study from a single tertiary center.

BACKGROUND

Rectal cancer has become one of the leading malignancies threatening people's health. For locally advanced rectal cancer (LARC), the comprehensive strategy combining neoadjuvant chemoradiotherapy (NCRT), total mesorectal excision (TME), and adjuvant chemotherapy has emerged as a standard treatment regimen, leading to favorable local control and long-term survival. However, in recent years, an increasing attention has been paid on the exploration of organ preservation strategies, aiming to enhance quality of life while maintaining optimal oncological treatment outcomes. Local excision (LE), compared with low anterior resection (LAR) or abdominal-perineal resection (APR) was introduced dating back to 1970's. LE has historically been linked to a heightened risk of recurrence compared to TME, potentially due to occult lymph node metastasis and intraluminal recurrence. Recent evidence has demonstrated that LE might be an alternative approach, instead of LAR or APR, in cases with favorable tumor regression after NCRT with potentially better quality of life. Therefore, a retrospective analysis of clinicopathological data from mid-low LARC patients who underwent LE after NCRT was conducted, aiming to evaluate the treatment's efficacy, safety, and oncologic prognosis.

AIM

To explore the safety, efficacy, and long-term prognosis of LE in patients with mid-low rectal cancer who had a good response to NCRT.

METHODS

Patients with LE between 2012 to 2021 were retrospectively collected from the rectal cancer database from Gastro-intestinal Ward III in Peking University Cancer Hospital. The clinicopathological features, postoperative complications, and long-term prognosis of these patients were analyzed. The Kaplan-Meier method was used to create cancer-specific survival curve, and the log-rank test was used to compare the differences regarding outcomes.

RESULTS

A total of 33 patients were included in this study. The median interval between NCRT and surgery was 25.4 (range: 8.7-164.4) weeks. The median operation time was 57 (20.0-137.0) minutes. The initial clinical T staging (cT): 9 (27.3%) patients were cT2, 19 (57.6%) patients were cT3, and 5 (15.2%) patients were cT4; The initial N staging (cN): 8 patients (24.2%) were cN negative, 25 patients (75.8%) were cN positive; The initial M stage (cM): 2 patients (6.1%) had distant metastasis (ycM1), 31 (93.9%) patients had no distant metastasis (cM0). The pathological results: 18 (54.5%) patients were pathological T0 stage (ypT0), 6 (18.2%) patients were ypT1, 7 (21.2%) patients were ypT2, and 2 (6.1%) patients were ypT3. For 9 cT2 patients, 5 (5/9, 55.6%) had a postoperative pathological result of ypT0. For 19 cT3 patients, 11 (57.9%) patients were ypT0, and 2 (40%) were ypT0 in 5 cT4 patients. The most common complication was chronic perineal pain (71.4%, 5/7), followed by bleeding (43%, 3/7), stenosis (14.3%, 1/7), and fecal incontinence (14.3%, 1/7). The median follow-up time was 42.0 (4.0-93.5) months. For 31 patients with cM0, the 5-year disease-free survival (DFS) rate, 5-year local recurrence-free survival (LRFS) rate, and 5-year overall survival (OS) rate were 88.4%, 96.7%, and 92.9%, respectively. There were significant differences between the ycT groups concerning either DFS ( = 0.042) or OS ( = 0.002) in the Kaplan-Meier analysis. The LRFS curve of ycT ≤ T1 patients was better than that of ycT ≥ T2 patients, and the value was very close to 0.05 ( = 0.070). The DFS curve of patients with ypT ≤ T1 was better than that of patients with ypT ≥ T2, but the value was not statistically significant ( = 0.560). There was a significant difference between the ypT groups concerning OS ( = 0.014) in the Kaplan-Meier analysis. The LRFS curve of ypT ≤ T1 patients was better than that of ypT ≥ T2 patients, and the value was very close to 0.05 ( = 0.070). Two patients with initial cM1 were alive at the last follow-up.

CONCLUSION

LE for rectal cancer with significant tumor regression after NCRT can obtain better safety, efficiency, and oncological outcome. Minimally invasive or nonsurgical treatment with patient participation in decision-making can be performed for highly selected patients. Further investigation from multiple centers will bring better understanding of potential advantages regarding local resection.