OBJECTIVES Transforming growth factor-beta (TGF-β) is a multifunctional regulatory factor. Here we measured serum soluble TGF-β (sTGF-β) levels and evaluated its dynamics and prognostic capabilities during chemotherapy in unresectable pancreatic cancer patients.

METHODS We prospectively enrolled 60 patients treated with FOLFIRINOX as the first-line palliative chemotherapy. We collected blood samples at the time of diagnosis, first response assessment, and disease progression and measured serum sTGF-β using an enzyme-linked immunosorbent assay.

RESULTS The patients' median overall survival (OS) and progression-free survival (PFS) were 10.3 (95% confidence interval [CI], 8.5-12.1) and 6.5 (95% CI, 4.9-8.1) months, respectively. Patients with low sTGF-β at diagnosis (<31.2 ng/mL) had better OS and PFS than patients with high sTGF-β, respectively, (OS, 13.7 vs 9.2 months; hazard ratio [HR], 2.602; P = .004; PFS, 9.0 vs 5.8 months; HR, 2.010; P = .034). At the time of disease progression, sTGF-β was increased compared with that of diagnosis (mean, 26.4 vs 23.9 ng/mL). In particular, sTGF-β was significantly increased at disease progression in patients with a partial response (mean, 25.7 vs 31.0 ng/mL; P = .049).

CONCLUSIONS Pretreatment sTGF-β levels can serve as a prognostic indicator in unresectable pancreatic cancer patients treated with FOLFIRINOX chemotherapy. Likewise, the dynamics of sTGF-β during chemotherapy have prognostic value.