Single centre experience with conversion surgery for advanced and metastatic gastric cancer in Slovakia

Abstract

Conversion surgery (CS) following systemic chemotherapy (SCT) has been suggested as a promising strategy for improving prognosis of patients with advanced gastric carcinoma (GC). The evidence, however, comes mostly from small-scale studies. Moreover, controversy exists over the criteria for selecting patients for SCT. We retrospectively analyzed 123 patients treated between 2007 and 2023. Thirty-one underwent CS, 44 received primary radical surgery (R0) with adjuvant chemotherapy (ACT), and 48 received surgical or palliative treatment. Survival rates and predictors of successful conversion were assessed. Median survival for R0 + ACT (30.4 months, 95%CI: 20.9-45.0) was non-significantly higher than SCT + R0 (19.4 months, 95%CI: 10.3-40.1; P = 0.2353). Successful downstaging after SCT was observed in 54.8% of CS patients. This group of SCT responders had significantly lower laboratory markers CEA, NLR and PLR (P-value of 0.019; 0.036 and 0.029, respectively). Both successful and failed conversion groups had significantly longer survival than group with palliative treatment (16.0 months, 95%CI: 8.4-19.1 vs. 7.4 months, 95%CI: 5.3-9.9; P = 0.0003). Multivariable analysis confirmed significantly lowered hazard and prolonged overall survival in CS vs. palliative treatments after adjusting for age and stage differences (P = 0.0014). Conversion therapy improves short-term survival and offers potential for long-term survival in select stage IV GC patients.

Keywords: Advanced cancer; Conversion surgery; Gastric cancer; Systemic chemotherapy.

Fig. 1

Kaplan-Meier curves for overall survival in patients with gastric cancer grouped by type of surgical treatment modality (the overall log rank test: P << 0.001). “דmark indicating events (deaths) and “+” mark indicating censored patients (survivors at the time point).

Fig. 2

Pairwise comparisons of the overall survival rates of patients who underwent successful conversion therapy (SCT + R0) with (1) patients in whom conversion failed (left: the log-rank test P = 0.0535 and generalized Wilcoxon test P = 0.1480) and (2) with patients having received ACT after radical surgery (right: the log rank test P = 0.1113 and generalized Wilcoxon test P = 0.1253). A remark: the Prentice modified Wilcoxon test is more sensitive than the log-rank test when the ratio of hazards is higher at early survival times than at late ones. In contrast, the log-rank test gives equal weight to death to all time points.