Basic surgical principles for locally advanced rectal cancer in complex therapy

Background . Compliance with principles of surgical oncology is necessary to choose effective treatment options for locally advanced rectal cancer (LARC). Objective : to show the basic surgical principles for LARC using a new option of complex therapy. Material and Methods . The basic surgical principles for LARC using a new option of complex therapy with polyradiomodifcation (local microwave hyperthermia + intrarectal administration of a polymer composition with Metronidazole) in combination with polychemotherapy (oral administration of Capecitabine + intravenous administration of Oxaliplatin) with concurrent prolonged hypofractionated radiation therapy were presented. Results . The treatment outcomes of the new option of complex neoadjuvant therapy with the compliance of surgical oncology principles were studied in 46 patients with LARC (T3cd-T4a N1c-2ab M0, CRM+, EMVI+). An analysis of the immediate outcomes showed that postoperative complications were diagnosed in only 4 (8.7 %) of 46 patients and no deaths were recorded. The local control was achieved: cancer recurrence was diagnosed in only 1 (2.2 %) and distant metastases in 4 (8.7 %) of patients. The 5-year recurrence-free survival rate in these patients was signifcantly higher than that observed in patients who received conventionally fractionated radiotherapy in combination with Capecitabine (81.0 vs 56.8 %, p=0.02). The improvement of results was achieved both by adhering to the principles of surgical oncology and increasing the radiosensitivity of the tumor: pathologic complete response was achieved in 35 (76.1 %) patients. This made it possible to perform sphincter-preserving surgeries in 71.7 % (33 out of 46) patients and in 66.7 % (18 out of 27) with lower-ampullary cancer. Conclusion . The use of a new method of complex therapy for LARC and compliance with the basic principles of surgical oncology allowed the improvement of long-term treatment outcomes by achieving local control of the tumor, contributing to the expansion of indications for performing sphincter-preservingsurgeries.