Outcome and prognostic factors in 593 non-metastatic rectal cancer patients: a mono-institutional survey

Predictors and survival outcomes of having less than 12 harvested lymph nodes in proctectomy for rectal cancer

BACKGROUND

Current recommendations suggest that a minimum of 12 lymph nodes (LNs) should be harvested during curative rectal cancer resection. We aimed to assess predictors and survival outcomes of harvesting < 12 lymph nodes in rectal cancer surgery.

METHODS

A retrospective case-control analysis of factors associated with harvesting < 12 LNs in rectal cancer surgery was conducted. Data were derived from the National Cancer Database 2010-2019. Univariate and multivariate binary logistic regression analyses were performed to determine predictors of harvesting < 12 LNs. Association between harvesting < 12 LNs and 5-year overall survival (OS) was assessed using Cox regression and Kaplan Meier statistics.

RESULTS

67,529 patients (60.8% male; mean age: 61.2 ± 12.5 years) were included. Median number of harvested LNs was 15 (IQR: 11-20); 27.1% of patients had < 12 harvested LNs. Independent predictors of harvesting < 12 LNs were older age (OR: 1.016;p < 0.001), neoadjuvant systemic treatment (OR: 1.522;p < 0.001), neoadjuvant radiation treatment (OR: 1.367;p < 0.001), longer duration of radiation therapy (OR: 1.003;p < 0.001) and abdominoperineal resection (OR: 1.071;p = 0.017). Higher clinical TNM stage and tumor grade, pull-through coloanal anastomosis, and minimally invasive surgery were independently associated with ≥ 12 harvested LNs. < 12 harvested LNs was independently associated with lower 5-year OS (HR: 1.24;p < 0.001) and shorter mean OS (96.7 vs 102.8 months;p < 0.001) than ≥ 12 harvested LNs.

CONCLUSIONS

Older age, open resection, and neoadjuvant therapy were independent predictors of < 12 harvested LNs. Conversely, higher clinical TNM stage and tumor grade, coloanal anastomosis, and minimally invasive surgery were predictive of ≥ 12 harvested LNs. < 12 LNs harvested was associated with lower OS.

An investigation into tumor regression grade as a parameter for locally advanced rectal cancer and 5-year overall survival rate

PURPOSE

The standard treatment for locally advanced rectal cancer (LARC) is neoadjuvant chemoradiation (nCRT) followed by surgery. Several parameters are associated with patient survival in LARC. One of these parameters is tumor regression grade (TRG); however, the significance of TRG remains controversial. In this study, we aimed to examine the correlations of TRG with 5-year overall (OS) and relapse-free survival (RFS) and identify other factors that influence the survival rates in LARC after nCRT followed by surgery.

METHODS

This retrospective study included 104 patients diagnosed with LARC who underwent nCRT followed by surgery at Songklanagarind Hospital from January 2010 to December 2015. All patients received fluoropyrimidine-based chemotherapy at a total dose of 45.0 to 50.4 Gy in 25 daily fractions. Tumor response was evaluated using the 5-tier Mandard TRG classification. TRG was categorized into good (TRG 1-2) and poor (TRG 3-5) responses.

RESULTS

TRG (classified by either the 5-tier classification system or the 2-group classification system) was not correlated with 5-year OS or RFS. The 5-year OS rates were 80.0%, 54.5%, 80.8%, and 67.4% in patients with TRG 1, 2, 3, and 4, respectively (P=0.22). Poorly differentiated rectal cancer and systemic metastasis were associated with poor 5-year OS. Intraoperative tumor perforation, poor differentiation, and perineural invasion were correlated with inferior 5-year RFS.

CONCLUSION

TRG was probably not associated with either 5-year OS or RFS; however, poor differentiation and systemic metastasis were strongly associated with poor 5-year OS.

Construction of a predictive model for clinical survival in male patients with non-metastatic rectal adenocarcinoma

BACKGROUND

No clinical prediction model is available for non-metastatic rectal adenocarcinoma in males. Based on demographic and clinicopathological characteristics, we constructed a survival prediction model for the study population.

METHODS

At a ratio of 7:3, 3450 eligible patients were divided into training and validation sets. Optimal cutoff values were calculated using X-tile software. Cox proportional hazards regression was used to find prognostic factors for cancer-specific survival (CSS) and overall survival (OS). Corresponding nomogram prognostic models were also constructed based on predictors.The validity, discriminative ability, predictability, and clinical usefulness of the model were analyzed and assessed.

RESULTS

We identified predictors of survival in the target population and successfully constructed nomograms. In the nomogram prediction model for OS and CSS, the C-index was 0.724 and 0.735, respectively, for the training group and 0.754 and 0.760, respectively, for the validation group. In the validation group, the area under the curve (AUC) of the receiver operating characteristic curve for OS and CSS nomograms was 0.768 and 0.769, respectively, for the 3-year survival rate and 0.755 and 0.747, respectively, for the 5-year survival rate. Kaplan-Meier Survival Curves showed excellent risk discrimination performance of the nomogram (P < 0.05) Calibration curves, time-dependent AUC and decision curve analysis showed that the prediction model constructed in this study had excellent clinical prediction and decision ability and performed better than the TNM staging system.

CONCLUSION

Our nomogram is helpful to evaluate the prognosis of non-metastatic male patients with rectal adenocarcinoma and has guiding significance for clinical treatment.

Factors Associated with Mortality among Patients with Colorectal Cancer at the Secondary Care Hospital in Southern Thailand: Hospital-Based Retrospective Cohort Study

Background

Globally and in Thailand, the incidence of colorectal cancer (CRC) is third-ranked behind lung and breast cancer, respectively. This hospital-based retrospective cohort study aimed to determine factors associated with mortality among patients with CRC.

Methods

This study was performed by using the secondary data of the cancer registry among patients with CRC registered in Phatthalung Hospital. Two hundred twenty-eight patients with CRC were diagnosed and followed up from January 2014 to December 2018. Multiple logistic regression analysis was used to analyze factors associated with mortality among subjects with CRC.

Results

The results revealed that the proportion of mortality among subjects with CRC was 50.44% (115 cases) at six months of following up. Subjects who had an increasing age every ten years (adjusted odds ratio [OR_adj] = 1.40, 95 percent confidence interval [95% CI]: 1.09-1.80) were diagnosed with CRC at stage 3 (2.64, 1.19-5.84) and at stage 4 (11.63, 2.69-50.15) more likely to die. Also, subjects who received a combination of chemotherapy and radiotherapy treatment (3.44, 1.20-9.85), combination treatment of surgery, and postoperative care (2.46, 1.22-4.94) were more likely to die. Subjects who had not had surgery treatment were more likely to die (35.00, 7.44-168.27).

Conclusions

In conclusion, factors such as the age of patients, stage of CRC, and treatment were associated with mortality among patients with CRC. Hence, medical and health professionals should consider these factors according to the treatment and optimization in patients with CRC.

Pre-Treatment Computed Tomography Radiomics for Predicting the Response to Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer: A Retrospective Study

Background and Purpose

Computerized tomography (CT) scans are commonly performed to assist in diagnosis and treatment of locally advanced rectal cancer (LARC). This study assessed the usefulness of pretreatment CT-based radiomics for predicting pathological complete response (pCR) of LARC to neoadjuvant chemoradiotherapy (nCRT).

Materials and Methods

Patients with LARC who underwent nCRT followed by total mesorectal excision surgery from July 2010 to December 2018 were enrolled in this retrospective study. A total of 340 radiomic features were extracted from pretreatment contrast-enhanced CT images. The most relevant features to pCR were selected using the least absolute shrinkage and selection operator (LASSO) method and a radiomic signature was generated. Predictive models were built with radiomic features and clinico-pathological variables. Model performance was assessed with decision curve analysis and was validated in an independent cohort.

Results

The pCR was achieved in 44 of the 216 consecutive patients (20.4%) in this study. The model with the best performance used both radiomics and clinical variables including radiomic signatures, distance to anal verge, lymphocyte-to-monocyte ratio, and carcinoembryonic antigen. This combined model discriminated between patients with and without pCR with an area under the curve of 0.926 and 0.872 in the training and the validation cohorts, respectively. The combined model also showed better performance than models built with radiomic or clinical variables alone.

Conclusion

Our combined predictive model was robust in differentiating patients with and without response to nCRT.

Structured and shared MRI staging lexicon and report of rectal cancer: A consensus proposal by the French Radiology Group (GRERCAR) and Surgical Group (GRECCAR) for rectal cancer

PURPOSE

To develop French guidelines by experts to standardize data acquisition, image interpretation, and reporting in rectal cancer staging with magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Evidence-based data and opinions of experts of GRERCAR (Groupe de REcherche en Radiologie sur le CAncer du Rectum [i.e., Rectal Cancer Imaging Research Group]) and GRECCAR (Groupe de REcherche en Chirurgie sur le CAncer du Rectum [i.e., Rectal Cancer Surgery Research Group]) were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of reporting template and protocol for data acquisition were collected; responses were analyzed and classified as "Recommended" versus "Not recommended" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts).

RESULTS

Consensus regarding patient preparation, MRI sequences, staging and reporting was attained using the RAND-UCLA Appropriateness Method. A consensus was reached for each reporting template item among the experts. Tailored MRI protocol and standardized report were proposed.

CONCLUSION

These consensus recommendations should be used as a guide for rectal cancer staging with MRI.

Prediction of cancer-specific survival and overall survival in middle-aged and older patients with rectal adenocarcinoma using a nomogram model

•

Summarise the established knowledge on this subject.1

Middle-aged and older patients are at high risk of rectal adenocarcinoma; however, studies comprehensively analysing its predictors and the construction of visual nomogram models are limited.

2

Most studies that reported on the prediction of colorectal cancer-related survival models had limited samples and included data from a single centre. The included predictors were limited, or the evaluation indicators were not easy to obtain, greatly limiting clinical application.

3

With the advancement of medical care, the clinical outcomes of patients with rectal adenocarcinoma have changed. Therefore, new, more comprehensive, and practical indicators are required for constructing clinical prediction models to effectively determine the prognosis of patients.

•

What are the significant and/or new findings of this study?1

We included demographic and clinicopathological data from thousands of middle-aged and elderly patients with rectal adenocarcinoma to find relevant prognostic factors. New cut-offs were developed and used for the construction of nomograms.

2

The nomogram constructed this time has excellent predictive ability and clinical decision-making ability, and has good clinical practicability.

3

The nomogram survival prediction model constructed this time can effectively help evaluate the prognosis of middle-aged and elderly patients with rectal adenocarcinoma and guide the selection of clinical treatment measures.

Objective

To develop a new nomogram tool for predicting survival in middle-aged and elderly patients with rectal adenocarcinoma.

Methods

A total of 6,116 patients were randomly assigned in a 7:3 ratio to training and validation cohorts. Univariate and multivariate Cox proportional hazards regression analyses were used to identify independent prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS) in the training set, and two nomogram prognostic models were constructed. The validity, accuracy, discrimination, predictive ability, and clinical utility of the models were assessed based on the concordance index (C-index), area under the receiver operating characteristics (ROC) curve, time-dependent area under the ROC curve (AUC), Kaplan-Meier survival curve, and decision curve analyses.

Results

Predictors of OS and CSS were identified, and nomograms were successfully constructed. The calibration discrimination for both the OS and CSS nomogram prediction models was good (C-index: 0.763 and 0.787, respectively). The AUC showed excellent predictive performance, and the calibration curve exhibited significant predictive power for both nomograms. The time-dependent AUC showed that the predictive ability of the predictor-based nomogram was better than that of the TNM stage. The nomograms successfully discriminated high-, medium-, and low-risk patients for all-cause and cancer-specific mortality. The decision curve demonstrated that the nomograms are useful with respect to good decision power.

Conclusion

Our nomogram survival prediction models may aid in evaluating the prognosis of middle-aged and older patients with rectal adenocarcinoma and guiding the selection of the clinical treatment measures.

Real-world clinical significance of nonbiological factors with staging, prognosis and clinical management in rectal cancer

BACKGROUND

The clinical guidance of the American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) staging system is established only in biological factors and does not include nonbiological factors (NBFs). We assessed the clinical value of incorporating NBFs into the TNM staging system in point of the clinical management and prognostic prediction accuracy of rectal cancer.

METHODS

We used the Surveillance, Epidemiology and End Results (SEER) database and identified 12,515 patients with rectal cancer who were diagnosed between 1 January 2011 and 31 December 2015. Multivariate Cox proportional hazards regression analysis and Kaplan-Meier curves were used to determine the probabilities of cancer-specific survival (CSS) according to different TNM-NBF stages.

RESULTS

Multivariate Cox regression analysis showed that county percentage with a bachelor's degree, insurance status, unemployment status, and marital status were all significant prognostic NBFs (p < 0.05). The concordance index of TNM-NBF stages was 0.815 (95% confidence interval (CI) 0.8072-0.8228). Multivariate Cox analyses showed that, compared with NBF0-stage, NBF1-stage was contacted with a 54.5% increased risk of cancer-specific mortality in rectal cancer, which increased to 68.3% in non-metastatic rectal cancer (all p < 0.001). NBF0-stage showed a CSS benefit as compared with NBF1-stage (p < 0.001).

CONCLUSIONS

We found that NBF-stage was an independent prognostic factor for survival in rectal cancer. The influence of NBFs on survival in rectal cancer warrants greater clinical attention. Furthermore, the consolidation of NBF-stage into the TNM staging system is crucial to better prognostic prediction accuracy and individualized risk-adaptive therapies.