The assessment of risk factors for long-term survival outcome in ypN0 patients with rectal cancer after neoadjuvant therapy and radical anterior resection

Development and validation of a nomogram to predict the risk factors of major complications after radical rectal cancer surgery

Purpose

The aim of this study was to establish a validated nomogram to predict risk factors for major post-operative complications in patients with rectal cancer (RC) by analyzing the factors contributing to major post-operative complications in RC patients.

Methods

We retrospectively collected baseline and surgical information on patients who underwent RC surgery between December 2012 and December 2022 at a single-center teaching hospital. The entire cohort was randomly divided into two subsets (60% of the data for development, 40% for validation). Independent risk factors for major post-operative complications were identified using multivariate logistic regression analyses, and predictive models were developed. Area under the curve (AUC) was calculated using receiver operating characteristic curve (ROC) to assess predictive probability, calibration curves were plotted to compare the predicted probability of the nomogram with the actual probability, and the clinical efficacy of the nomogram was assessed using decision curve analysis (DCA).

Results

Our study included 3151 patients who underwent radical surgery for RC, including 1892 in the development set and 1259 in the validation set. Forty (2.1%) patients in the development set and 26 (2.1%) patients in the validation set experienced major post-operative complications. Through multivariate logistic regression analysis, age (p<0.01, OR=1.044, 95% CI=1.016-1.074), pre-operative albumin (p<0.01, OR=0.913, 95% CI=0.866-0.964), and open surgery (p<0.01, OR=2.461, 95% CI=1.284-4.761) were identified as independent risk factors for major post-operative complications in RC, and a nomogram prediction model was established. The AUC of the ROC plot for the development set was 0.7161 (95% Cl=0.6397-0.7924), and the AUC of the ROC plot for the validation set was 0.7191 (95% CI=0.6182-0.8199). The predicted probabilities in the calibration curves were highly consistent with the actual probabilities, which indicated that the prediction model had good predictive ability. The DCA also confirmed the good clinical performance of the nomogram.

Conclusion

In this study, a validated nomogram containing three predictors was created to identify risk factors for major complications after radical RC surgery. Due to its accuracy and convenience, it could contribute to personalized management of patients in the perioperative period.

Comparison of complications and bowel function among different reconstruction techniques after low anterior resection for rectal cancer: a systematic review and network meta-analysis

BACKGROUND

Anastomosis for gastrointestinal reconstruction has been contentious after low anterior resection of rectal cancer for the past 30 years. Despite the abundance of randomized controlled trials (RCTs) on colon J-pouch (CJP), straight colorectal anastomosis (SCA), transverse coloplast (TCP), and side-to-end anastomosis (SEA), most studies are small and lack reliable clinical evidence. We conducted a systematic review and network meta-analysis to evaluate the effects of the four anastomoses on postoperative complications, bowel function, and quality of life in rectal cancer.

METHODS

We assessed the safety and efficacy of CJP, SCA, TCP, and SEA in adult patients with rectal cancer after surgery by searching the Cochrane Library, Embase, and PubMed databases to collect RCTs from the date of establishment to May 20, 2022. Anastomotic leakage and defecation frequency were the main outcome indicators. We pooled data through a random effects model in a Bayesian framework and assessed model inconsistency using the deviance information criterion (DIC) and node-splitting method and inter-study heterogeneity using the I-squared statistics (I²). The interventions were ranked according to the surface under the cumulative ranking curve (SUCRA) to compare each outcome indicator.

RESULTS

Of the 474 studies initially evaluated, 29 were eligible RCTs comprising 2631 patients. Among the four anastomoses, the SEA group had the lowest incidence of anastomotic leakage, ranking first (SUCRA_SEA = 0.982), followed by the CJP group (SUCRA_CJP = 0.628). The defecation frequency in the SEA group was comparable to those in the CJP and TCP groups at 3, 6, 12, and 24 months postoperatively. In comparison, the defecation frequency in the SCA group 12 months after surgery all ranked fourth. No statistically significant differences were found among the four anastomoses in terms of anastomotic stricture, reoperation, postoperative mortality within 30 days, fecal urgency, incomplete defecation, use of antidiarrheal medication, or quality of life.

CONCLUSIONS

This study demonstrated that SEA had the lowest risk of complications, comparable bowel function, and quality of life compared to the CJP and TCP, but further research is required to determine its long-term consequences. Furthermore, we should be aware that SCA is associated with a high defecation frequency.

Robotic versus Laparoscopic Total Mesorectal Excision Surgery in Rectal Cancer: Analysis of Medium-Term Oncological Outcomes

Background. Robotic systems can overcome some limitations of laparoscopic total mesorectal excision (L-TME), thus improving the quality of the surgery. So far, many studies have reported the technical feasibility and short-term oncological results of robotic total mesorectal excision (R-TME) in treating rectal cancer (RC); however, only a few evaluated the survival and long-term oncological outcomes. The following study compared the medium-term oncological data, 3-year overall survival (OS), and disease-free survival (DFS) of L-TME and R-TME in patients with rectal cancer. Methods. In this retrospective study, records of patients (patients with stage I-III rectal cancer) who underwent surgery (127 cases of L-TME and 148 cases of R-TME) at the Gansu Provincial Hospital between June 2016 and March 2018 were included in the analysis. Kaplan-Meier analysis evaluated the 3-year OS and DFS for all patients treated with curative intent. Results. The conversion rate was significantly higher, and the postoperative hospital stay was significantly longer in the L-TME group than in the R-TME group (all P<.05). Major complications were significantly lower in the robotic group (P<.05). The 3-year DFS rate (for all stages) was 74.8% for L-TME and 85.8% for R-TME (P = .021). For disease stage III, the 3-year DFS and OS were significantly higher in the R-TME group (P<.05). Conclusion. R-TME can achieve better oncological outcomes and is more beneficial for RC patients compared with L-TME, especially for those with stage III rectal cancers. Nevertheless, further randomized controlled trials and a longer follow-up period are needed to confirm these findings.

Correlation of Presacral Tumour Recurrence with Tumour Metastasis and Long-Term Tumour Recurrence Risk in Patients with Rectal Cancer

Objective

To explore the risk factors that affect long-term presacral tumour recurrence in patients with rectal cancer (RC) after radical rectal cancer resection.

Methods

In our study, a total of 50 patients with presacral tumour recurrence after radical resection of RC in our hospital between May 2017 and May 2018 were enrolled in the observation group, and the other 50 patients without presacral tumour recurrence after the resection over the same span were enrolled in the control group. The two groups were compared in distant metastatic rate and long-term recurrence, and corresponding K-M curves were drawn. Additionally, the quality of life of the two groups was also compared. Patients in both groups were assigned to a long-term recurrence group or a non-long-term recurrence group based on their long-term recurrence, and a multivariate logistic regression analysis was carried out for analysis of risk factors of long-term recurrence.

Results

The two groups were not greatly different in clinical data (P > 0.05). The observation group was higher than the control group in terms of distant metastasis and long-term recurrence (P < 0.05). In addition, the MOS 36-Item Short-Form Health Survey (SF-36) scores of the observation group were all lower than those of the control group in the eight dimensions (P < 0.05). Moreover, tumour diameter (OR: 0.315, 95% CI: 0.118–0.835), differentiation (OR: 2.652, 95% CI: 1.086–6.852), and presacral recurrence (OR: 2.370, 95% CI: 1.263–4.447) were all independent risk factors for long-term recurrence of patients undergoing radical resection of RC.

Conclusions

Patients undergoing radical resection of RC face greatly higher risks of presacral tumour distant metastasis and long-term tumour recurrence, and tumour diameter ≥ 5 cm, low-differentiation degree, and presacral recurrence are independent risk factors for long-term recurrence of patients undergoing radical resection of RC. In the future, when performing radical resection of rectal cancer, it is necessary to pay attention to the changes in the above indicators in patients so as to prevent tumour recurrence.