Int J Clin Oncol. 2025 Apr 26. doi: 10.1007/s10147-025-02742-0. Online ahead of print.
ABSTRACT
BACKGROUND: The standard adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC) in Japan is S-1; however, the impact of dose reduction on prognosis remains unclear. We have reported that total dose intensity (TDI) ≥ 62.5% indicates good prognosis. This multicenter retrospective study evaluated the prognostic impact of TDI ≥ 62.5% and reduced dosing in patients who underwent radical resection for PDAC across three institutions.
METHOD: Patients were grouped into high-TDI (≥ 62.5%) and low-TDI (< 62.5%) based on this cutoff. We performed an inverse probability of treatment weighting (IPTW)-adjusted analysis and calculated relapse-free survival (RFS) and overall survival (OS). OS was also calculated for high TDI with TDI < 100% and TDI = 100%.
RESULT: Among 487 patients, 274 were included: 152 in the low-TDI and 122 in high-TDI groups. Patient background was adjusted using IPTW based on factors that might influence TDI. The median RFS for low- and high-TDI was 8 and 18 months, respectively (p = 0.004). The median OS of low- and high-TDI groups was 20 and 50 months, respectively (p < 0.001). Among patients with high TDI, OS did not differ between those with TDI < 100% and those with TDI = 100% (median, 47 vs. 72 months, p = 0.208).
CONCLUSION: It has been suggested that a partial dose reduction of S-1 as adjuvant chemotherapy for PDAC does not significantly impact prognosis.
PMID:40287608 | DOI:10.1007/s10147-025-02742-0
