Low anterior resection syndrome and methods of its assessment (literature review)

Low anterior resection syndrome is a common problem due to the increased incidence of rectal cancer and the high incidence of anorectal dysfunction during sphincter-preserving surgical interventions. The influence of functional disorders on the quality of life of patients and changes in social adaptation makes it possible to attribute the syndrome of low anterior resection to topical and discussed issues.Purpose of the study: to consider the features of the development of anorectal dysfunction in patients with rectal cancer by studying risk factors and pathogenetic aspects of the development of low anterior resection syndrome, as well as to evaluate the role of objective studies in assessing the syndrome according to published literature. The etiology of low anterior resection syndrome is multifactorial. Unmodified and modified predictors are distinguished among the risk factors. Unmodified factors include female gender and age over 65 years. Among the modifiable predictors, radiation therapy, surgical intervention, the type of formed colorectal anastomosis and the development of its insolvency, as well as the elimination of intestinal stoma have a negative effect on anorectal function. Nevertheless, the greatest role in its development is played by organ-preserving surgery with total mesorecumectomy, radiation therapy and the formation of a preventive ileostomy. The complexity of the pathophysiological mechanism of the syndrome necessitates a detailed study of anorectal function and changes in its parameters in patients during treatment for rectal cancer. Functional disorders in low anterior resection syndrome vary in severity. In the study of the severity of clinical manifestations of the syndrome, the use of the LARS scale is important, and in the development of anal incontinence, the use of the Wexner scale is important. However, the most accurate assessment can be carried out by objective research methods, such as high-resolution anorectal manometry. This research method allows to control the function of the rectal obturator apparatus at different stages of combined treatment and unwraps the possibility of searching for new predictors of low anterior resection syndrome.