Importance of the neoadjuvant rectal (NAR) score to the outcome of neoadjuvant chemotherapy alone for locally advanced rectal cancer

Efficacy Analysis of Combining Sintilimab with Neoadjuvant Chemotherapy in Treating Middle and Advanced Rectal Cancer Based on Big Data

Objective

To analyze the efficacy of combining sintilimab with neoadjuvant chemotherapy in treating middle and advanced rectal cancer based on big data.

Methods

According to the inclusion and exclusion criteria, 43 patients with middle and advanced rectal cancer, who were treated with sintilimab and neoadjuvant chemotherapy in General Surgery of the hospitals of Zhangjiakou city from January 2020 to January 2022, were selected for the retrospective study. The patients' short-term efficacy was scientifically evaluated, and the factors affecting efficacy and the correlation were analyzed.

Results

Among the 43 enrolled patients, 30 of them had regional lymphatic metastasis but none had distant metastasis; most patients were at Broders II and TNM III, and all of them had adenocarcinoma; the total response rate was 69.77% (30 cases), with no grade IV and V adverse reactions; the patients were divided into the effective group and the ineffective group after treatment based on the evaluation results of short-term efficacy, and analysis of the relevant factors exposed in both groups revealed significant differences in age, tumor size, CEA, NLR value, PLR value, TNM stage, and presence of combined lymphatic metastasis between the two groups (P < 0.05); univariate analysis showed that tumor size, CEA, TNM stage, and combined lymphatic metastasis were the independent risk factors affecting the efficacy in patients with middle to advanced rectal cancer (P < 0.05); and through the Spearman correlation analysis of the above independent risk factors, it was further confirmed that tumor size, CEA, TNM stage, and combined lymphatic metastasis were negatively correlative with the efficacy of combining sintilimab with neoadjuvant chemotherapy in treating middle to advanced rectal cancer (P < 0.05).

Conclusion

Combining sintilimab with neoadjuvant chemotherapy has good efficacy and safety profile, which is conducive to subsequent surgery; in contrast, larger tumor diameter, higher CEA level, higher TNM stage, and more serious lymphatic metastasis are all independent risk factors affecting treatment sensitivity and can lead to poor efficacy.

Neoadjuvant rectal score is prognostic for survival: A population-based propensity-matched analysis

INTRODUCTION

Neoadjuvant rectal (NAR) score may serve as a surrogate short-term endpoint for overall survival (OS) in clinical trials. This study aims to test the NAR score using a large, national cancer registry.

METHODS

National Cancer Database patients with clinical stage II/III rectal adenocarcinoma (RAC) treated with neoadjuvant chemoradiation (CRT) followed by surgery were selected and divided into low-, intermediate-, and high-NAR subgroups. OS outcomes were analyzed using Kaplan-Meier and logistic regression models.

RESULTS

A total of 12 452 patients were selected, of which 5071 (40.7%) were in clinical stage II and 7381 (59.3%) were in clinical stage III; 15.2% had pathologic complete response. The mean NAR score was 10.01 ± 10.61. Six thousand nine hundred and forty-one (55.7%) did not receive adjuvant chemotherapy (AC) and were propensity-matched across NAR subgroups (966 in each group). A significant difference in 5-year OS between low-, intermediate-, and high-NAR groups was observed (85% vs. 76% vs. 68%; p < 0.001). Five thousand five hundred and eleven (44.3%) received AC and 1045 triplets were propensity-matched per NAR groups. A significant difference was again observed for 5-year OS (93% vs. 88% vs. 75%; p < 0.001). Logistic regression confirmed NAR strata as a significant predictor of 5-year OS.

CONCLUSION

NAR score, as a neoadjuvant response measure, is a strong predictor of 5-year OS, regardless of AC receipt in a heterogenous population of locally advanced RAC patients.

The concept and use of the neoadjuvant rectal score as a composite endpoint in rectal cancer

There is no universally accepted instrument to use as a validated surrogate endpoint for overall survival in phase 2 and phase 3 multimodal rectal cancer trials using chemoradiotherapy. Efforts are hampered by the inaccuracy of clinical TNM staging, the variability of indications for neoadjuvant treatment, and diverse definitions of tumour regression grade. Pathological complete response is commonly used, but fails to capture information from the majority of patients. The neoadjuvant rectal score categorises response and downstaging from the entire trial population to identify whether or not a novel treatment group in a chemoradiation trial is superior by predicting overall survival outcomes. Additionally, the neoadjuvant rectal score assesses the difference between initial clinical and pathological T stage and the presence or absence of nodal involvement after treatment. The neoadjuvant rectal score has been conceptually, but incompletely, statistically validated by two independent trial datasets. However, a fundamental weakness of the score is that no preoperative phase 3 trials in locally advanced rectal cancer in the past 20 years have provided a significant benefit in overall survival to statistically validate the neoadjuvant rectal score as a surrogate endpoint for overall survival. We review the robustness, practical value, applicability, generalisability, advantages, and disadvantages of the neoadjuvant rectal score as a surrogate endpoint for overall survival and recommend how this score could be improved and be acceptable as a standard endpoint in studies investigating neoadjuvant chemotherapy and chemoradiation in patients with rectal cancer.

Neoadjuvant rectal (NAR) score: Value evaluating the efficacy of neoadjuvant therapy and prognostic significance after surgery?

INTRODUCTION

The Neoadjuvant rectal (NAR) score is a new surrogate endpoint to be used in clinical trials for early determination of treatment response to different preoperative therapies. The aim is to further validate the NAR-score, primarily developed using chemoradiotherapy (CRT) with a delay to surgery 6-8 weeks, and explore its value using other schedules.

MATERIALS AND METHODS

The study included all 9978 patients diagnosed with non-metastasized RC in 2007-2015 that had undergone surgery and was registered in the Swedish Colorectal Cancer Registry. The patients of interest had either short-course radiotherapy (scRT)/CRT + delayed surgery, long-course radiotherapy (RT) + delayed surgery, (C)RT + additional chemotherapy, primary surgery, or scRT + immediate surgery. The scRT/CRT + delayed surgery groups were further divided based on time to surgery.

RESULTS

Mean NAR-score differed significantly (p < 0.0001) between different treatments. (C)RT + additional chemotherapy had the lowest mean score of 16.3 and CRT + delayed surgery had 17.7. There was a significant difference (p < 0.05) in overall survival (OS) and time to recurrence (TTR) of patients with a Low NAR-score (<8) compared to those with a High score (>16) for both CRT- and scRT, with a stronger correlation for CRT-patients. C-index for the NAR-score model (0.623) was not superior to when only pathological T- and N-stage was used (0.646).

CONCLUSIONS

The NAR-score is prognostic, but it is not better than pT- and pN-stage. However, the NAR-score can still discriminate between two treatments that have different cell killing effect and may still be of value in clinical trials as an easier method than pT- and N-stage.

Prognostic and Predictive Value of NAR Score in Gastric Cancer

INTRODUCTION

Neoadjuvant treatment is a widely accepted approach for locally advanced rectum cancer. Efforts to explore a surrogate endpoint for clinical trials revealed a new prognostic scoring system which is named as neoadjuvant rectal score (NAR) in patients who received neoadjuvant treatment for rectal cancer.

MATERIAL AND METHODS

88 patients who met inclusion criteria were included in the study. The optimal cutoff value of the NAR score was 17.6 with 71% sensitivity and 63% specificity. Patients with NAR score > 17.6 (n: 48, 54%) were defined as the high-risk group and those with NAR score ≤ 17.6 (n: 40, 56%) as the low-risk group.

RESULT

Survival analysis according to the NAR score group (low-risk vs high-risk) revealed that there was a statistically significant difference between groups regarding OS and DFS. The median OS for high-risk patients was 27.3 months (95% CI, 15.0-39.6); it was 76.6 months (47.3-106.0) for low-risk patients (p < 0.0001). The median DFS was 15.1 months (11.8-18.4) for high-risk patients; it was 44.3 months (95% CI, 4.1-84.6) in the low-risk group (p = 0.002).

DISCUSSION

As a result, we interpreted our findings as supporting data about the utility of NAR score not only as a surrogate endpoint for the clinical trial of rectal cancer but also as a prognostic marker in patients with gastric cancer who received neoadjuvant treatment.