Introduction. Pelvic side wall could be involved by tumor or desmoplastic reaction in patients with gynaecological pelvic malignancies and rectal cancer. Up until recently surgery was considered to have no prospects due to high frequency of palliative procedures and low survival rate. Aim. To conduct a retrospective analysis of short-and long-term results in patients after laterally extended endopelvic resection. Materials and methods. This study included consecutive patients between 2013 and 2023, who undergone laterally extended endopelvic resection at the Leningrad Regional Oncology Center named by L.D. Roman. Principal data were collected and classified. G. Vizzielli and R. Naik classification formed the grounds for surgery type selection. Procedure was considered to be radical with no signs of macro-and microscopic tumor presence in surgical margins. Results. Over the 2013 to 2023 period 54 laterally extended endopelvic resections were performed. Of these, 50 (92.6 %) were woman and 4 (7.4 %) men. An R0 resection was performed in 44 (81 %) of 54 cases, postoperative morbidity was 67 % with 5,6 % mortality, and 5-year overall survival of 23 %. 5-year overall survival was reached only in patients with colorectal cancer (44 %) and uterus tumors (40 %). In case of palliative procedures (R1/R2 resection) overall survival was less than 3 years. Conclusion. Clear resection margin was considered to be the crucial prognostic factor. An improvement of surgical techniques, an exploration of pelvic side wall structures, and sensible patient selection could improve short-and long-term outcomes in this complex group of patients.