1. Ulmasov FG, Dzhuraev MD, Yusupbekov AA, Egamberdiev DM. Surgical treatment of locally advanced tumors of retroperitoneum. Oncology and Radiology of Kazakhstan. 2017;2(44):62–66. (In Russ.).
2. Vashakmadze LA, Cheremisov VV. Nonorganic retroperitoneal tumors: state‑of‑the‑art. Russian Journal of Oncology. 2008;2:45–48. (In Russ.).
3. Hui JY. Epidemiology and Etiology of Sarcomas. Surg Clin North Am. 2016 Oct;96(5):901–914. https://doi.org/10.1016/j.suc.2016.05.005
4. Kaprin AD, Starinskii VV, Shakhzadova AO. The status of cancer care for the population of Russia in 2021. Мoscow: P. Hertsen Moscow Oncology Research Institute – Branch of the National Medical Research Radiological Centre, Ministry of Health of the Russian Federation, Moscow, Russian Federation, 2022, 239 p. (In Russ.). Available at: https://oncology‑association.ru/wp-content/uploads/2022/05/sostoyanie-onkologicheskoj-pomoshhi-naseleniyu-rossii-v-2021-godu.pdf. Accessed: 15.02.2023
5. Yang BL, Gu YF, Shao WJ, Chen HJ, Sun GD, Jin HY, Zhu X. Retrorectal tumors in adults: magnetic resonance imaging findings. World J Gastroenterol. 2010 Dec 14;16(46):5822–5829. https://doi.org/10.3748/wjg.v16.i46.5822