Modified gemcitabine, S-1, and leucovorin combination for patients with newly diagnosed locally advanced or metastatic pancreatic adenocarcinoma: A multi-center retrospective study in Taiwan

[[abstract]]BACKGROUND: In pancreatic cancer, toxicities associated with current chemotherapeutic regimens remain concerning. A modified combination of gemcitabine, S-1, and leucovorin (GSL) was used as the first-line treatment for newly diagnosed locally advanced or metastatic pancreatic adenocarcinoma patients. METHODS: GSL was administered every 2 weeks-intravenous gemcitabine 800 mg/m2 at a fixed-dose rate of 10 mg/m2/min on day 1 and oral S-1 (80-120 mg/day) plus leucovorin 30 mg twice daily on days 1-7. We retrospectively analyzed the feasibility of GSL and patient outcomes in three medical centers in Taiwan. RESULTS: Overall, 49 patients received GSL with a median follow-up of 24.9 months from May 2015 to March 2019. The median patient age was 68 years (range, 47-83 years), with a marginally higher number of females (57.1%). Among the 44 patients who underwent image evaluation, 13 demonstrated a partial response (29.5%) and 17 presented with stable disease (38.6%). The partial response rate and stable disease rate was 26.5% and 34.7%, respectively, in the intent-to-treat analysis. The median time-to-treatment failure was 5.79 months (95% C.I., 2.63-8.94), progression-free survival was 6.94 months (95% C.I., 5.55-8.33), and overall survival time was 11.53 months (95% C.I., 9.94-13.13). For GSL treatment, the most common grade 3 or worse toxicities were anemia (18.3%), neutropenia (6.1%), nausea (4.1%), and mucositis (4.1%). Treatment discontinuation was mostly due to disease progression (65.3%). CONCLUSIONS: The modified GSL therapy can be a promising and affordable treatment for patients with advanced and metastatic pancreatic cancer in Taiwan. A prospective trial of modified GSL for elderly patients is currently ongoing in Taiwan