Author contribution: Egiazaryan KA — statement of the problem of managing the patients, manuscript editing; Ratyev AP — study concept, literature review, interpretation of the treatment outcomes; Miroshnikova EA — developing the study concept, theoretical justification of treatment, surgical treatment and monitoring of patients, data acquisition and analysis; Zhavoronkov EA — treatment of patients, postoperative management, assessment of medium-term treatment outcomes; Abilemets AS — surgical treatment, monitoring of patients, data acquisition and analysis, assessment of midterm treatment outcomes, manuscript editing.

Compliance with ethical standards: the study was approved by the Ethics Committee of Pirogov Russian National Research Medical University (protocol No. 181 of 28 January 2018). All patients submitted the informed consent to study participation.