Tumor regression and nodal status to neoadjuvant chemotherapy as a prognostic marker in patients with locally advanced gastric and gastroesophageal cancer

Gastric cancer is one of the most common malignancies with a poor prognosis. In the western population, it is diagnosed mainly as a locally advanced disease. Surgical treatment alone is associated with a high risk of disease recurrence, therefore the current standard of care is multimodality treatment based on perioperative chemotherapy and surgery. Currently, there are no biomarkers which would enable clinical practitioners to predict early response to the induction treatment.

This retrospective study was aimed at demonstrating that the pathological response to neoadjuvant chemotherapy is a reliable predictive factor of survival in patients with locally advanced gastric and gastroesophageal cancer. It was an academic, nonrandomized, retrospective study, conducted in MSCNRIO. Between January 2018 and December 2021 we analysed 220 patients aged 30-77 (median 63 years, 62.5% male and 37.5% female) with histologically confirmed GC or GEJ cancer. The patients were qualified by MDT for perioperative treatment (FLOT regimen). Pathological response of the primary tumor to neoadjuvant chemotherapy was evaluated according to Becker classification.

In the postoperative histopathological specimen, negative lymph nodes (ypN0) were reported in 51.8% (114) patients and positive lymph nodes (ypN+) were reported in 44.0%(97) patients. Median overall survival (mOS) was 51.7 months in ypN0 group (CI 95%; 48.6-54.8) and 33.6 months in ypN+ group (95% CI; 29.2-37.9), which was statistically significant (p < 0.001). According to the Becker classification, TRG1a – 12% (27), TRG1b – 14% (31), TRG2 - 31% (69) and TRG3 - 38% (84) patients were reported, and median overall survival (mOS) was 53.7 (CI 95%; 48.0-59.3), 51.9 (CI 95%; 45.9-57.9), 42.7 (CI 95%; 36.2-49.2), 28.3 (CI 95%; 37.7-44.7), respectively (p < 0.001).

Pathological response could be considered as a reliable predictive factor of survival in this setting and could be considered as a valuable surrogate end point of clinical trial apart from OS.

The authors.

Has not received any funding.

All authors have declared no conflicts of interest.