Do we have enough Foreknowledge to predict the low anterior resection syndrome (LARS) score preoperatively?

Machine learning model for prediction of low anterior resection syndrome following laparoscopic anterior resection of rectal cancer: A multicenter study

BACKGROUND

Low anterior resection syndrome (LARS) severely impairs patient postoperative quality of life, especially major LARS. However, there are few tools that can accurately predict major LARS in clinical practice.

AIM

To develop a machine learning model using preoperative and intraoperative factors for predicting major LARS following laparoscopic surgery of rectal cancer in Chinese populations.

METHODS

Clinical data and follow-up information of patients who received laparoscopic anterior resection for rectal cancer from two medical centers (one discovery cohort and one external validation cohort) were included in this retrospective study. For the discovery cohort, the machine learning prediction algorithms were developed and internally validated. In the external validation cohort, we evaluated the trained model using various performance metrics. Further, the clinical utility of the model was tested by decision curve analysis.

RESULTS

Overall, 1651 patients were included in the present study. Anastomotic height, neoadjuvant therapy, diverting stoma, body mass index, clinical stage, specimen length, tumor size, and age were the risk factors associated with major LARS. They were used to construct the machine learning model to predict major LARS. The trained random forest (RF) model performed with an area under the curve of 0.852 and a sensitivity of 0.795 (95%CI: 0.681-0.877), a specificity of 0.758 (95%CI: 0.671-0.828), and Brier score of 0.166 in the external validation set. Compared to the previous preoperative LARS score model, the current model exhibited superior predictive performance in predicting major LARS in our cohort (accuracy of 0.772 for the RF model vs 0.355 for the preoperative LARS score model).

CONCLUSION

We developed and validated a robust tool for predicting major LARS. This model could potentially be used in the clinic to identify patients with a high risk of developing major LARS and then improve the quality of life.

Transcultural adaptation and validation of the Moroccan Arabic dialect version of the Wexner incontinence score in patients with low anterior resection syndrome after rectal surgery

BACKGROUND

Bowel dysfunction symptoms such as stool clustering, urgency, incomplete voiding, and fecal incontinence are frequent after colorectal surgery and known as the low anterior resection syndrome. The Wexner score is the most widely used tool for fecal incontinence assessment. We aimed to translate and test the psychometric properties of the Moroccan Arabic dialect version of the Wexner questionnaire in patients with low anterior resection syndrome after rectal surgery.

METHODS

The Wexner questionnaire was translated to Moroccan Arabic and administered to a group of 158 patients, among which a subgroup of 43 patients took the test for a second time to examine test-retest reliability. Cronbach alpha coefficient was used to determine internal consistency and correlation, and the European Organisation for the Research and Treatment of Cancer Quality of Life C30 and the low anterior resection syndrome questionnaires were assessed for convergent validity. Discriminant validity was demonstrated through the Wexner score ability to detect differences based on the patients' different clinical and pathological characteristics.

RESULTS

One hundred and fifty-eight patients completed the Moroccan Arabic dialect version of the Wexner score, which showed an excellent internal consistency with a Cronbach alpha score of 0.91. Test-retest reliability was established by a Bland-Altman plot with 95% limits of agreement. The score showed positive correlation to the low anterior resection syndrome score (r = 0.748; P < .001) and the European Organisation for the Research and Treatment of Cancer Quality of Life C30 diarrhea symptom scale (r = 0.519; P < .001). A negative correlation was also demonstrated for each one of the 5 European Organisation for the Research and Treatment of Cancer quality of life C30 functional scales, namely physical functioning (r = -0.217 ; P = .006), role functioning (r = -0.267; P = .001), emotional functioning (r = -0.266; P = .001), cognitive functioning (r = -0.283; P < .001), and social functioning (r = -0,283; P < .001). The Wexner score differed between patients according to tumor location, chemoradiotherapy, type of mesorectal excision, and anastomosis.

CONCLUSION

The Moroccan Arabic dialect version of the Wexner score shows good psychometric properties and can be used for fecal incontinence assessment, particularly in colorectal cancer patients.

Validation of the Moroccan arabic version of the low anterior resection syndrome score

Background

Sphincter sparing surgery is oftentimes associated with bowel dysfunction complaints, namely the low anterior resection syndrome (LARS). The LARS questionnaire is widely used to assess this syndrome. The aim of this observational study is to translate this tool into arabic and test its psychometric properties in rectal cancer patients, in order to ease its use in clinical practice and future research.

Methods

The LARS questionnaire was translated to arabic and administered to a total of 143 patients. A subgroup of 42 patients took the test twice for test-retest reliability. Internal consistency was examined through cronbach’s alpha. The score results were correlated to the EORTC QLQ-C30 questionnaire for convergent validity assessment, while discriminant validity was established through the ability of the LARS score to differentiate patients with different clinical and pathological criteria.

Results

The Moroccan Arabic version of the LARS score was completed by 143 patients. The internal consistency was demonstrated through a cronbach alpha score of 0.66. The agreement between the test and retest was established by a Bland Altman plot with 95% limits of agreement. 85.6% of patients remained in the same LARS category. The LARS score showed negative correlation with all five of the QLQ-C30 functional scales as well as positive correlation to the diarrhea symptom scale. The questionnaire score differed between patients according to their tumor location, chemoradiotherapy, type of mesorectal excision and anastomosis.

Conclusion

The Moroccan Arabic version of the LARS score shows good psychometric properties and can be used for bowel dysfunction assessment in clinical and research settings.