NEOADJUVANT CHEMORADIOTHERAPY IN THE MULTIMODALITY TREATMENT OF STAGE IIIA(N2) NON-SMALL CELL LUNG CANCER (NSCLC)

Abstract

Summary. The choice of optimal treatment for stage IIIA(N2) non-small cell lung cancer (NSCLC) remains controversial, since the five-year survival rate of this category of patients cannot meet modern medical requirements and patient expectations even after radical surgery and chemotherapy (CT). Accordingly, the analysis of available clinical data and the search for the most effective multimodal treatment option are constantly ongoing. The main treatment strategy for stage IIIA(N2) NSCLC is surgery with induction CT. As part of a comprehensive clinical approach, neoadjuvant CT (NCT) is used to eliminate distant micrometastases, leading to increased survival in an independent operation. Meanwhile, induction with concurrent chemoradiotherapy (CRT) followed by surgery resulted in a 30% to 40% improvement in 5-year survival. Aim: to evaluate the results of treatment of patients with stage IIIA(N2) NSCLC after the use of various methods of neoadjuvant and adjuvant therapy in case of surgical intervention. Object and methods: the effect of NCRT was performed in 37 patients with stage IIIA(N2) NSCLC in selected tumors of the lungs and the middle of the National Cancer Institute. This group of patients was planned for multimodal treatment, which included 3 or 4 cycles of chemotherapy with platinum-based drugs following the regimens of cisplatin + docetaxel or carboplatin + paclitaxel with one-hour radiotherapy (RT), consisting of sessions in the or classical fractionation with a single dose of 2 Gy, SOD up to 50 Gy with subsequent surgery. The number of CT cycles (3 or 4) depended on the result of the control observation of the dynamics of regression of the tumor process. In the core of the vicoristan group, there was the first control group of stage IIIA(N2) NSCLC patients with NCT (n = 194). This group of patients was given 3 or 4 courses of CT using a regimen similar to the main group: cisplatin / carboplatin + docetaxel / paclitaxel, and in the second control group – similar to the number of courses and drugs, neoadjuvant CT and RT in SOD 50 Gy in adjuvant regimen (n = 60) with further surgical treatments. All patients, depending on the prevalence of the tumor process, underwent radical surgery in the form of lobectomy, bilobectomy or pneumonectomy with mediastinal lymphodissection. Results: median survival in the main group was 30.12 months, in the first control group (NCT) – 23.68 months and the second control group (NCT + adjuvant RT) – 23.23 months, respectively. In the main group, 5 (14.7%) patients were diagnosed with a complete morphological response of the primary tumor and a complete morphological response of the tumor tissue in the regional lymph nodes. In addition to the complete morphological response of the primary tumor and metastatic mediastinal lymph nodes (tumor cells were not detected in histological preparations), in 5 (14.7%) cases, a pronounced morphological response of a highly differentiated tumor was detected (residual viability of tumor tissue to 12±5%). These patients had a higher median survival (45 and 39 months, respectively) compared to controls. Conclusion: the treatment regimen with NCRT is more promising for increasing patient survival.