A New Prediction Model for Local Recurrence After Curative Rectal Cancer Surgery: Development and Validation as an Asian Collaborative Study

Analysis of Local Recurrence After Robotic-Assisted Total Mesorectal Excision (ALRITE): An International, Multicentre, Retrospective Cohort

BACKGROUND/OBJECTIVES

Rectal cancer is a major global health issue with high morbidity and mortality rates. Local recurrence (LR) significantly impacts patient outcomes, decreasing survival rates and often necessitating extensive secondary treatments. While robot-assisted total mesorectal excision (R-TME) is becoming a preferred method for rectal cancer surgery due to its improved precision and visualisation, long-term data on LR and predictors of recurrence remain limited. This study aims to determine the 3-year LR rate following R-TME and to identify predictors of recurrence to enhance patient selection and the personalisation of treatment.

METHODS

This retrospective international multicentre cohort study included 1039 consecutive rectal cancer patients who underwent R-TME between 2013 and 2020, with a minimum of 3 years of follow-up. Data from tertiary colorectal centres in the United Kingdom, the Netherlands, Spain, France, Italy, and Belgium were analysed. Potential predictors of LR were identified using backward elimination, and four machine learning models were evaluated for predicting LR.

RESULTS

The 3-year LR rate was 3.8%. Significant predictors of LR included advanced clinical M-staging, length of the hospital stay, postoperative ileus, postoperative complications, pathological N-staging, the completeness of resection, and the resection margin distance. The eXtreme Gradient Boosting model performed best for LR prediction, with a final accuracy of 77.1% and an AUC of 0.76.

CONCLUSIONS

R-TME in high-volume centres achieves low 3-year LR rates, suggesting that robot-assisted surgery offers oncological safety and advantages in rectal cancer management. This study underscores the importance of surgical precision, patient selection, and standardised perioperative care, supporting further investment in robotic training to improve long-term patient outcomes.

Predicting extensive metastasis in postoperative oligometastatic colorectal cancer

PURPOSE

Oligometastatic colorectal cancer (OMCRC) patients can achieve long-term disease control with multidisciplinary treatment. However, the development of extensive metastasis worsens prognosis and restricts treatment options. This study aims to develop a predictive model for extensive metastasis in OMCRC to assist in clinical decision-making.

METHODS

Clinical and pathological data for OMCRC patients were collected from the Second Affiliated Hospital of Soochow University. Patients were randomly divided into training and testing cohorts. Risk factors for extensive metastasis were identified through LASSO regression analysis and COX regression analysis. Three predictive models were developed in the training cohort and validated in the testing cohort: COX regression analysis, Extreme Gradient Boosting (XGBoost), and Survival Support Vector Machine (SurvSVM). Finally, the optimal model was visualized with the nomogram.

RESULTS

A total of 214 patients with OMCRC were enrolled in the study. Four independent risk factors were identified: whether surgery has been undertaken following oligometastasis (WST), histological type (HT), carcinoembryonic antigen at the last follow-up (CAE at last-FU), and preoperative albumin to globulin ratio (Preop-AGR). In the testing cohort, the COX model (1-year AUC = 0.82, 3-year AUC = 0.72, 5-year AUC = 0.85, mean AUC = 0.80) performed best. Decision curve analysis (DCA) confirmed the net benefit of the Cox model, and the nomogram provided accurate predictions of metastasis risk.

CONCLUSION

CAE at last-FU, Preop-AGR, HT, and WST are independent risk factors for extensive metastasis in OMCRC. The nomogram model incorporating risk factors can assist clinicians in developing optimal treatment for OMCRC patients.

Prognostic Impact of the Postoperative Carcinoembryonic Antigen Level after Curative Resection of Locally Advanced Rectal Cancer

Objectives

This study was conducted to investigate whether preoperative or postoperative carcinoembryonic antigen (CEA) with a new cut-off value is more optimal for predicting long-term outcomes in patients with Stage II/III rectal cancer, and to investigate the effectiveness of postoperative adjuvant chemotherapy (POAC) based on the CEA values.

Methods

Serum CEA levels were measured preoperatively (pre-CEA) and postoperatively (post-CEA). The area under the receiver operating curve (AUROC) was used to determine a cut-off for CEA. The cut-off for CEA relative to recurrence-free survival (RFS) was established as that giving the highest AUROC. In comparison of superiority between pre- and post- CEA levels, Akaike's information criterion (AIC) was used in the Cox proportional-hazard regression model.

Results

The subjects were 323 patients who underwent curative surgical treatment for Stage II/III rectal cancer. AIC values indicated that RFS was better stratified by a post-CEA level with a cut-off of 2.3 ng/ml compared with other classifications of pre- or post- CEA. In Stage III or high-risk Stage II cases, there was no effect of POAC on RFS in those with post-CEA <2.3 ng/ml (p=0.39), but in those with post-CEA ≥2.3 ng/ml there was a trend for better RFS in patients who received POAC compared to those without POAC (p=0.06).

Conclusions

Patients with post-CEA ≥2.3 ng/ml had worse long-term outcomes compared with those with post-CEA <2.3 ng/ml. Post-CEA with a cut-off of 2.3 ng/ml may be useful in determining the indication for POAC for in Stage III or high-risk Stage II cases.

The Constrained Disorder Principle Overcomes the Challenges of Methods for Assessing Uncertainty in Biological Systems

Different disciplines are developing various methods for determining and dealing with uncertainties in complex systems. The constrained disorder principle (CDP) accounts for the randomness, variability, and uncertainty that characterize biological systems and are essential for their proper function. Per the CDP, intrinsic unpredictability is mandatory for the dynamicity of biological systems under continuously changing internal and external perturbations. The present paper describes some of the parameters and challenges associated with uncertainty and randomness in biological systems and presents methods for quantifying them. Modeling biological systems necessitates accounting for the randomness, variability, and underlying uncertainty of systems in health and disease. The CDP provides a scheme for dealing with uncertainty in biological systems and sets the basis for using them. This paper presents the CDP-based second-generation artificial intelligence system that incorporates variability to improve the effectiveness of medical interventions. It describes the use of the digital pill that comprises algorithm-based personalized treatment regimens regulated by closed-loop systems based on personalized signatures of variability. The CDP provides a method for using uncertainties in complex systems in an outcome-based manner.

Multicenter validation of the PREDICT score for prediction of local recurrence after total mesorectal excision of rectal cancer

BACKGROUND

Total mesorectal excision (TME) is the gold standard treatment for rectal cancer. Although TME has managed to decrease the rates of local recurrence after rectal cancer resection, local recurrence is still recorded at varying rates. The present study aimed to validate the PREDICT score in the prediction of local recurrence of rectal cancer after TME with curative intent.

METHODS

This was a retrospective multicenter study on patients with nonmetastatic low or middle rectal cancer who underwent TME. The total PREDICT score was calculated for every patient and related to the onset of local recurrence. According to the final score, patients were allocated to one of three risk groups: low, moderate, and high, and the rates of local recurrence in each group were calculated and compared.

RESULTS

The present study included 262 patients (50.4% males) with a mean age of 47.1 years. The overall local recurrence rate was 12.6%. 29.4% of patients were in the low-risk group, 63.7% in the moderate-risk group, and 6.9% in the high-risk group. The local recurrence rate was 3.9% (95% confidence interval [CI]: 0.8-10.9) in the low-risk group, 13.2% (95% CI: 8.4-19.3) in the moderate risk group, and 44.4% (95% CI: 21.5-69.2) in the high-risk group (p < 0.0001). The sensitivity of the PREDICT score was 72.7%, the specificity was 88.1%, and the accuracy was 86.3%.

CONCLUSIONS

The PREDICT score had good diagnostic accuracy in the prediction of local recurrence after TME and a good discriminatory ability in the differentiation between patients at different risks to develop local recurrence.

Effect of Tumor Location on Outcome After Laparoscopic Low Rectal Cancer Surgery: A Propensity Score Matching Analysis

BACKGROUND

Dissection of the distal anterolateral aspect of the mesorectum remains a surgical challenge for low rectal cancer, posing a higher risk of residual mesorectum, which might lead to the increased incidence of local recurrence for patients with anterior wall involvement.

OBJECTIVE

This study aimed to assess the effect of tumor location on outcome after laparoscopic low rectal cancer surgery.

DESIGN

This is a single-center, retrospective study.

SETTINGS

The study was conducted at West China Hospital in China.

PATIENTS

Patients with low rectal cancer who underwent laparoscopic total mesorectal excision from 2011 to 2016 were enrolled. Patients were divided into anterior and nonanterior groups according to tumor location. Propensity score matching analysis was used to reduce the selection bias.

MAIN OUTCOME MEASURES

The primary end point was local recurrence. The secondary end points included overall survival, disease-free survival, and the positive rate of circumferential resection margin.

RESULTS

A total of 404 patients were included, and 176 pairs were generated by propensity score matching analysis. Multivariate analysis showed that anterior location was an independent risk factor of local recurrence (HR, 12.6; p = 0.006), overall survival (HR, 3.0; p < 0.001), and disease-free survival (HR, 2.3; p = 0.001). For patients with clinical stage II/III or T3/4, anterior location remained a prognostic factor for higher local recurrence and poorer survival. Local recurrence was rare in patients with clinical stage II/III (1.4%) or T3/4 (1.5%) tumors that were not located anteriorly.

LIMITATIONS

This study was limited by its retrospective nature.

CONCLUSIONS

Anterior location is an independent risk factor of local recurrence, overall survival, and disease-free survival for low rectal cancer. More strict and selective use of neoadjuvant therapy should be considered for patients who have clinical stage II/III or T3/4 tumors that are not located anteriorly. A larger cohort study is warranted to validate the prognostic role of anterior location for low rectal cancer. See Video Abstract at http://links.lww.com/DCR/B622.

IMPACTO DE LA LOCALIZACIN DEL TUMOR EN EL RESULTADO POSTERIOR A CIRUGA LAPAROSCPICA DE CNCER DE RECTO INFERIOR UN PUNTAJE DE PROPENSIN POR ANLISIS DE CONCORDANCIA

ANTECEDENTES:La disección de la cara anterolateral distal del mesorrecto sigue siendo un desafío quirúrgico en el cáncer de recto inferior, constituyendo un alto riesgo de mesorrecto residual, que podría ocasionar una mayor incidencia de recurrencia local en pacientes con compromiso de la pared anterior.OBJETIVO:El objetivo del estudio fue evaluar el efecto de la localización del tumor en el resultado posterior a la cirugía laparoscópica de cáncer de recto inferior.DISEÑO:Estudio restrospectivo de un único centro.ÁMBITO:El estudio se realizó en el West China Hospital en China.PACIENTES:Pacientes con cáncer de recto inferior que se sometieron a excisión mesorrectal total laparoscópica entre 2011 y 2016. Los pacientes se dividieron en grupos, anterior y no anterior, según la localización del tumor. Se utilizó un puntaje de propensión por análisis de concordancia para reducir el sesgo de selección.PRINCIPALES VARIABLES EVALUADAS:El objetivo principal fue la recurrencia local. Los objetivos secundarios incluyeron la sobrevida global, la sobrevida libre de enfermedad y la tasa de positividad del margen de resección circunferencial.RESULTADOS:Se incluyeron un total de 404 pacientes y se generaron 176 pares mediante un puntaje de propensión por análisis de concordancia. El análisis multivariado mostró que la localización anterior era un factor de riesgo independiente de recidiva local (HR = 12,6, p = 0,006), sobrevida global (HR = 3,0, p <0,001) y sobrevida libre de enfermedad (HR = 2,3, p = 0,001). En pacientes con estadio clínico II /III o T3/4, la ubicación anterior continuó como un factor pronóstico para una mayor recurrencia local y una menor sobrevida. La recidiva local fue excepcional en pacientes con tumores en estadio clínico II / III (1,4%) o T3 / 4 (1,5%) que no estaban localizados hacia anterior.LIMITACIONES:Este estudio estuvo limitado por su carácter retrospectivo.CONCLUSIONES:La localización anterior es un factor de riesgo independiente de recidiva local, sobrevida global y sobrevida libre de enfermedad para el cáncer de recto inferior. Se debe considerar un uso más estricto y selectivo de la terapia neoadyuvante para pacientes en estadio clínico II / III o T3 /4 de tumores que no se localizan hacia anterior. Se justifica un estudio de cohorte más grande para validar el impacto pronóstico de una ubicación anterior del cáncer de recto inferior. Consulte Video Resumen en http://links.lww.com/DCR/B622. (Traducción-Dr. Lisbeth Alarcon-Bernes).

Bayesian network structure for predicting local tumor recurrence in rectal cancer patients treated with neoadjuvant chemoradiation followed by surgery

Background and Purpose

Tumor recurrence, a characteristic of malignant tumors, is the biggest concern for rectal cancer survivors. The epidemiology of the disease calls for a pressing need to improve healthcare quality and patient outcomes. Prediction models such as Bayesian networks, which can probabilistically reason under uncertainty, could assist caregivers with patient management. However, some concerns are associated with the standard approaches to developing these structures in medicine. Therefore, this study aims to compare Bayesian network structures that stem from these two techniques.

Patients and Methods

A retrospective analysis was performed on 6754 locally advanced rectal cancer (LARC) patients enrolled in 14 international clinical trials. Local tumor recurrence at 2, 3, and 5-years was defined as the endpoints of interest. Five rectal cancer treating physicians from three countries elicited the expert structure. The algorithmic structure was inferred from the data with the hill-climbing algorithm. Structural performance was assessed with calibration plots and area under the curve values.

Results

The area under the curve for the expert structure on the training and validation data was above 0.9 and 0.8, respectively, for all the time points. However, the algorithmic structure had superior predictive performance over the expert structure for all time points of interest.

Conclusion

We have developed and internally validated a Bayesian networks structure from experts' opinions, which can predict the risk of a LARC patient developing a tumor recurrence at 2, 3, and 5 years. Our result shows that the algorithmic-based structures are more performant and less interpretable than expert-based structures.

Intraoperative adverse events as a risk factor for local recurrence of rectal cancer after resection surgery

AIM

Failure to achieve a radical resection as well as intraoperative rectal perforation are important risk factors for local recurrence after rectal cancer surgery, but the importance of other intraoperative adverse events for the prognosis is unknown. The aim of this study was to assess the occurrence of intraoperative adverse events during rectal cancer surgery, and to determine whether these were associated with an increased risk of local recurrence.

METHODS

A retrospective population-based cohort study was undertaken, including all patients in Region Västra Götaland, Sweden, who had undergone primary resection surgery for rectal cancer diagnosed between 2010 and 2014, registered in the Swedish Colorectal Cancer Registry. Data were retrieved from the registry and through review of the medical records.

RESULTS

In total, 1208 patients were included in the study of whom 78 (6%) developed local recurrence during the follow-up period of at least 5 years. Intraoperative adverse events were common and occurred in 62/78 (79%) of patients with local recurrence compared to 604/1130 (53%) of patients without local recurrence. In multivariate analysis intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer, as were nonradical resection, a high pathological T stage, the presence of lymph node metastases, type of surgery and refraining from rectal washout during anterior resection and Hartmann's procedure.

CONCLUSIONS

Intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer and could possibly be used together with other known risk factors to select patients for intensified postoperative surveillance.

PCR-based quantitative detection of intraperitoneal free cancer cells for predicting locoregional recurrence after rectal cancer resection

INTRODUCTION

Locoregional recurrence after curative resection remains an important issue in the treatment of colorectal cancer (CRC). The aim of the present study was to investigate the clinical significance of quantitative detection of intraperitoneal free cancer cells by a PCR-based method for predicting locoregional recurrence after CRC resection.

METHOD

A total of 114 patients with CRC were enrolled between March 2017 and December 2018, and 95 patients with Stage I-III CRC were analyzed. Peritoneal lavage fluid was collected before and after tumour resection and subjected to cytology and quantitative reverse transcription-PCR (qRT-PCR) with carcinoembryonic antigen (CEA) as a genetic marker.

RESULTS

2.1% of patients had positive cytology after resection, whereas 9.5% had positive CEA qRT-PCR (PCR+) after resection. Eight of nine PCR+ patients after resection had tumours in the rectum. Fifteen (15.8%) patients developed recurrence during the follow-up period, including three with locoregional recurrence. One of 86 (1.2%) PCR- patients and 2 of 9 (22.2%) PCR+ patients after resection developed locoregional recurrence. Overall and in rectal cancer patients, the 3-year cumulative risk of locoregional recurrence was 25.0% and 28.6% for PCR+ patients, which is significantly higher than PCR- patients (1.3% and 0%, P < 0.001 and P = 0.001, respectively).

CONCLUSION

Intraperitoneal free cancer cells can serve as a sensitive predictor of locoregional recurrence after rectal cancer resection. qRT-PCR for CEA can be a suitable method for detecting intraperitoneal free cancer cells in peritoneal lavage fluid.

Diagnostic accuracy of follow-up tests for detecting colorectal cancer recurrences in primary care: A systematic review and meta-analysis

INTRODUCTION

Traditionally, follow-up of colorectal cancer (CRC) is performed in secondary care. In new models of care, the screening part care could be replaced to primary care. We aimed to synthesise evidence on the diagnostic accuracy of commonly used screeners in CRC follow-up applicable in primary care: carcinoembryonic antigen (CEA), ultrasound and physical examination.

METHODS

Medline, EMBASE, Cochrane Trial Register and Web of Science databases were systematically searched. Studies were included if they provided sufficient data for a 2 × 2 contingency tables. QUADAS-2 was used to assess methodological quality. We performed bivariate random effects meta-analysis, generated a hypothetical cohort, and reported sensitivity and specificity.

RESULTS

We included 12 studies (n = 3223, median recurrence rate 19.6%). Pooled estimates showed a sensitivity for CEA (≤ 5 μg/l) of 59% [47%-70%] and a specificity of 89% [80%-95%]. Only few studies reported sensitivities and specificities for ultrasound (36-70% and 97-100%, respectively) and clinical examination (23% and 27%, respectively).

CONCLUSION

In practice, GPs could perform CEA screening. Radiological examination in a hospital setting should remain part of the surveillance strategy. Personalised algorithms accounting for recurrence risk and changes of CEA-values over time might add to the diagnostic value of CEA in primary care.

The development and validation of a predictive model for recurrence in rectal cancer based on radiological and clinicopathological data

OBJECTIVE

To develop a prediction model for recurrence by incorporating radiological and clinicopathological prognostic factors in rectal cancer patients.

METHODS

All radiologic and clinicopathologic data of 489 patients with rectal cancer, retrospectively collected from a single institution between 2009 and 2013, were used to develop a predictive model for recurrence using the Cox regression. The model performance was validated on an independent cohort between 2015 and 2017 (N = 168).

RESULTS

Out of 489 derivative patients, 103 showed recurrence after surgery. The prediction model was constructed with the following four significant predictors: distance from anal verge, MR-based extramural venous invasion, pathologic nodal stage, and perineural invasion (HR: 1.69, 2.09, 2.59, 2.29, respectively). Each factor was assigned a risk score corresponding to HR. The derivation and validation cohort were classified by sum of risk scores into 3 groups: low, intermediate, and high risk. Each of these groups showed significantly different recurrence rates (derivation cohort: 13.4%, 35.3%, 61.5 %; validation cohort: 6.2%, 23.7%, 64.7%). Our new model showed better performance in risk stratification, compared to recurrence rates of tumor node metastasis (TNM) staging in the validation cohort (stage I: 3.6%, II: 12%, III: 30.2%). The area under the receiver operating characteristic curve of the new prediction model was higher than TNM staging at 3-year recurrence in the validation cohort (0.853 vs. 0.731; p = .009).

CONCLUSIONS

The new risk prediction model was strongly correlated with a recurrence rate after rectal cancer surgery and excellent for selection of high-risk group, who needs more active surveillance.

KEY POINTS

• Multivariate analysis revealed four significant risk factors to be MR-based extramural venous invasion, perineural invasion, nodal metastasis, and the short distance from anal verge among the radiologic and clinicopathologic data. • Our new recurrence prediction model including radiologic data as well as clinicopathologic data showed high predictive performance of disease recurrence. • This model can be used as a comprehensive approach to evaluate individual prognosis and helpful for the selection of highly recurrent group who needs more active surveillance.

Factors influencing recurrence of stage I-III rectal cancer in regional Australia

BACKGROUND

As treatments for rectal cancer improve with developments in surgical techniques, radiotherapy and chemotherapy, the nature of recurrences are evolving. We used a comprehensive database of a large Australian population with stage I-III rectal adenocarcinoma to identify timing and prognostic significance of recurrences, and factors associated with risk of developing recurrent disease.

METHODS

All patients with locoregional rectal cancer treated with curative intent in our health district from 2006 to 2017 were included. Multivariate analysis using Cox regression models were used to identify factors associated with recurrence.

RESULTS

A total of 483 patients were included. Recurrence occurred in 117 (24.2%) of 483 patients, being locoregional in 15 (3.1%) patients, distant in 85 patients (17.6%) and both locoregional and distant in 17 (3.5%) patients. Compared to those with locoregional recurrence, those with both locoregional and distant recurrence had worse cancer-specific survival. On univariate analysis, factors associated with recurrence included stage, grade, radiotherapy, chemotherapy, surgery type and distal tumour location. Factors which remained significant on multivariate analysis included higher grade and stage.

CONCLUSION

In the era of multimodality therapy for rectal cancer, recurrences are predominantly distant. Traditional predictors including higher stage, grade and distal tumour location remain independently associated with recurrence, despite current treatment paradigms.

Risk factors and risk prediction models for colorectal cancer metastasis and recurrence: an umbrella review of systematic reviews and meta-analyses of observational studies

BACKGROUND

There is a clear need for systematic appraisal of models/factors predicting colorectal cancer (CRC) metastasis and recurrence because clinical decisions about adjuvant treatment are taken on the basis of such variables.

METHODS

We conducted an umbrella review of all systematic reviews of observational studies (with/without meta-analysis) that evaluated risk factors of CRC metastasis and recurrence. We also generated an updated synthesis of risk prediction models for CRC metastasis and recurrence. We cross-assessed individual risk factors and risk prediction models.

RESULTS

Thirty-four risk factors for CRC metastasis and 17 for recurrence were investigated. Twelve of 34 and 4/17 risk factors with p < 0.05 were estimated to change the odds of the outcome at least 3-fold. Only one risk factor (vascular invasion for lymph node metastasis [LNM] in pT1 CRC) presented convincing evidence. We identified 24 CRC risk prediction models. Across 12 metastasis models, six out of 27 unique predictors were assessed in the umbrella review and four of them changed the odds of the outcome at least 3-fold. Across 12 recurrence models, five out of 25 unique predictors were assessed in the umbrella review and only one changed the odds of the outcome at least 3-fold.

CONCLUSIONS

This study provides an in-depth evaluation and cross-assessment of 51 risk factors and 24 prediction models. Our findings suggest that a minority of influential risk factors are employed in prediction models, which indicates the need for a more rigorous and systematic model construction process following evidence-based methods.

Does A Longer Waiting Period After Neoadjuvant Radio-chemotherapy Improve the Oncological Prognosis of Rectal Cancer?: Three Years' Follow-up Results of the Greccar-6 Randomized Multicenter Trial

OBJECTIVE

The aim of this study was to report the 3-year survival results of the GRECCAR-6 trial.

SUMMARY BACKGROUND DATA

Current data on the effect of an extended interval between radiochemotherapy (RCT) and resection for rectal cancer on the rate of complete pathological response (pCR = ypT0N0) is controversial. Furthermore, its effect on oncological outcomes is unknown.

METHODS

The GRECCAR-6 trial was a phase III, multicenter, randomized, open-label, parallel-group, controlled trial. Patients with cT3/T4 or TxN+ tumors of the mid or lower rectum who had received RCT (45-50 Gy with 5-fluorouracil or capecitabine) were included and randomized into a 7- or 11-week waiting period. Primary endpoint was the pCR rate. Secondary endpoints were 3-year overall (OS), disease-free survival (DFS), and recurrence rates.

RESULTS

A total of 265 patients from 24 participating centers were enrolled. A total of 253 patients underwent a mesorectal excision. Overall pCR rate was 17% (43/253). Mean follow-up from surgical resection was 32 ± 8 months. Twenty-four deaths occurred with an 89% OS at 3 years. DFS was 68.7% at 3 years (75 recurrences). Three-year local and distant recurrences were 7.9% and 23.8%, respectively. The randomization group had no impact on the 3-year OS (P = 0.8868) or DFS (P = 0.9409). Distant (P = 0.7432) and local (P = 0.3944) recurrences were also not influenced by the waiting period. DFS was independently influenced by 3 factors: circumferential radial margin (CRM) ≤1 mm [hazard ratio (HR) = 2.03; 95% confidence interval (CI), 1.17-3.51], ypT3-T4 (HR = 2.69; 95% CI, 1.19-6.08) and positive lymph nodes (HR = 3.62; 95% CI, 1.89-6.91).

CONCLUSION

Extending the waiting period by 4 weeks following RCT has no influence on the oncological outcomes of T3/T4 rectal cancers.

Factors predicting recurrence after curative resection for rectal cancer: a 16-year study

BACKGROUND

The recurrence after curative surgery of the rectal adenocarcinoma is a serious complication, considered as a failure of the therapeutic strategy. The aim of this study was to identify the different prognostic factors affecting the recurrence of adenocarcinoma of the rectum.

METHODS

A retrospective analysis of patients operated for adenocarcinoma of the rectum between January 2000 and December 2015 was conducted. The study of the recurrence rate and prognostic factors was performed through the Kaplan Meier survival curve and the Cox regression analysis.

RESULTS

During the study period, 188 patients underwent curative surgery for rectal adenocarcinoma, among which 53 had a recurrence. The recurrence rate was 44.6% at 5 years. The multivariate analysis identified four parameters independently associated with the risk of recurrence after curative surgery: a distal margin ≤ 2 cm (HR = 6.8, 95% CI 2.7-16.6, 6), extracapsular invasion of lymph node metastasis (HR = 4.4, 95% CI 1.3-14), tumor stenosis (HR = 4.3, 95% CI 1.2-15.2), and parietal invasion (pT3/T4 disease) (HR = 3, 95% CI 1.1-9.4).

CONCLUSION

The determination of the prognostic factors affecting the recurrence of rectal adenocarcinoma after curative surgery allows us to define the high-risk patients for recurrence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03899870 . Registered on 2 February 2019, retrospectively registered.