ESTRO 2025 - Abstract Book

S1870

Clinical – Upper GI

ESTRO 2025

Conclusion: Omitting surgery in patients achieving cCR does not compromise survival compared to patients who underwent surgery. In patients under the age of 70 with scc histology, there might be an advantage to surgery compared to surveillance alone.

Keywords: Esophageal cancer, surgery, chemoradiation

4592

Poster Discussion Neoadjuvant chemoradiotherapy in operable gastric cancer: 20-year results of the phase II trial. Jerzy Wydmański, Aleksander Zajusz Radiation Therapy, Maria Sklodowska-Curie National Research Institute of Oncology, Gliwice Branch, Gliwice, Gliwice, Poland Purpose/Objective: At the beginning of this century, neoadjuvant chemoradiotherapy (NCHRT) in the treatment of gastric cancer was researched in several oncological centers. Despite promising results that include good tolerance to treatment, high resection rate (79% - 100%) and 5% - 35% complete histological regressions, it was not introduced as standard treatment to clinical practice. There are insufficient publications that analyze long-term survival after NCHRT. Therefore, after 20 years of the completion of the phase II trial, we reassessed the preoperative chemoradiotherapy of the treatment results of 40 patients. The analysis provided the failure pattern of treatment and the rate of complications. Material/Methods: A total of 40 patients with operable gastric cancer were investigated, 14 women (35%) and 26 men (65%), with a median age of 58 years (range, 38-78 years). Treatment consisted of preoperative chemoradiotherapy, followed by surgery and adjuvant chemotherapy. A total dose of 45 Gy was administered in 25 fractions to the stomach and regional lymph nodes. Concomitant chemotherapy regimens were based on a combination of 5FU with LV. After 6 weeks, gastrectomy and D2 lymphadenectomy were performed. The patient then received 4 cycles of 5-FU/LV. Complete pathological regression or partial regression was observed in 7 (17.5%) and 8 (20%) patients, respectively. Among 30 pts. after R0 surgery, 10 pts. (33.3%) had recurrences of the diseases. Distant metastases were observed in 8 cases (26,7%), in 3 cases (10%) concurrently with locoregional recurrences. A single locoregional recurrence was observed in 2 cases (6.6%). The median time to recurrence was 2.8 years (range, 0.7 – 19.7 years). The overall survival (OS) of 10, 15 and 20 years and cancer specific survival (CSS) were; 56%, 45%, 30% (med 9.6 years) and 59%, 57%, 45% (med 20 years), respectively. Multivariate analysis demonstrated that two prognostic factors before treatment: weight loss greater than 10% (HR=3.364, 95% CI 1.478-7.655, P = 0.004) and pretreatment hemoglobin concentration less than 13 g% (HR = 0.316, 95% CI 0.143-0.707, P=0.005) were negatively significant for OS. Conclusion: Our results suggest that preoperative chemoradiotherapy is a promising strategy as a neoadjuvant therapy in patients with locally advanced operable gastric cancer. The high rate of pathological response and R0 resection, low rate of local recurrence, and high percent of 20-year survival rate afterward may suggest that chemoradiotherapy is effective in treating gastric cancer. Results: Of 40 patients, 37 patients underwent surgery. The resectability rate was 87%, and the R0 resection rate was 81%.

Keywords: gastric cancer, preoperative chemoradiotherapy