A phase II study of gemcitabine-based chemoradiotherapy (CCRT) after triplet induction chemotherapy (ICT) for locally advanced pancreatic cancer (LAPC): A Taiwan Cooperative Oncology Group (TCOG) study

Abstract

e15562 The optimal management of LAPC remains controversial. The efficacy of CCRT is hampered by early systemic dissemination. To treat undetectable metastases and to select patients who are likely to benefit from CCRT, ICT followed by CCRT has recently been extensively evaluated in LAPC. Recently, we showed that triplet chemotherapy consisting of gemcitabine 800 mg/m2 (10 mg/m2/min) followed by oxaliplatin 85 mg/m2 and 48-hour infusion of 5-FU/LV 3,000 and 150 mg/m2 Q 2 weeks, the GOFL regimen, is feasible and active for pts with APC. Chemo-naïve pts with histo- /cytologically proven unresectable LAPC, and bi-dimensionally measurable diseases were eligible. Patients who did not experience disease progression (PD) after 6 cycles of GOFL would had CCRT consisting of weekly gemcitabine 400mg/m2 plus 50.4Gy/28 fractions of radiation 4–6 weeks later. After CCRT, pts were re-evaluated for surgical intervention and those with unresectable disease would continue GOFL until PD, unacceptable toxicity, patient's refusal or death. Among the 50 enrolled pts (24F/26M, median age 58.5 years), 48 had definitively unresectable diseases. After induction GOFL, 16 (32%) pts were off-studied because of PD in 12 (24%) and ICT-related toxicity in 4 (8%, PD/UE group). Among the 34 (68%) with objective response or stable disease after 6 cycles of ICT, 27 (54%) who completed the assigned multimodality treatment are categorized as CCRT group; whiles 7 (14%) who either declined CCRT (in 5) or still on ICT (in 2) are categorized as non-CCRT group. The median PFS and OS for the ITT population were 9.1 and 14.5 months, respectively. The median PFS for PD/UE, non-CCRT and CCRT groups were 2.1, 8.2 and 12.8 months, respectively; whiles the OS were 8.5, 15.0 and 18.3 months, respectively. The most common grade 3–4 toxicities were neutropenia (40%), anemia (14%), infection (16%), nausea (26%), vomiting (20%). Grade 2–3 peripheral neuropathy was observed in 7 of 29 who received post-CCRT GOFL. Conclusion: Three months of triplet ICT followed by gemcitabine-based CCRT is feasible and likely to prolong the survival of selected LAPC pts. Prospective, randomization study is warranted to validate the findings. No significant financial relationships to disclose.