Comparison of Efficacy Between Full-dose GEM CCRT and 5FU CCRT in Locally Advanced Pancreatic Cancer = Comparison of Efficacy Between Full-dose GEM CCRT and 5FU CCRT in Locally Advanced Pancreatic Cancer

다국어 초록 (Multilingual Abstract)

Background: Concurrent chemoradiotherapy (CCRT) is a standard therapeutic option for managing locally advanced pancreatic cancer (LAPC). Although 5-Fluorouracil (5-FU) or gemcitabine are recommended as the reference chemotherapeutic agent for CCRT, the optimal dosage for CCRT is still controversial. Aim: To compare the therapeutic efficacy and tolerability of full-dose gemcitabine based CCRT (FG-CCRT) and low dose 5-FU based CCRT (5FU-CCRT) for LAPC. Methods & Materials: From January 2006 to March 2013, 110 patients with LAPC who received FG-CCRT (n=90) or 5FU-CCRT (n=20) were included for retrospective analysis. FG-CCRT included full-dose weekly gemcitabine monotherapy (1000 mg/m2) or combination therapy with cisplatin (70 mg/m2). 5FU-CCRT treated with radiosensitizing low dose of bolus 5-FU (500mg/m2, weekly) plus leucovorin (20mg/m2). Concurrent radiotherapy targeted the primary tumor with 5 to 10 mm margin without regional lymph node irradiation. One month after completion of CCRT, response evaluation was conducted by computed tomography scan. Results: FG-CCRT had more advanced T-stage at the time of diagnosis (T4-86.7% versus 60.0%; p=0.005). Objective response rate (ORR) and disease control rate (DCR) was significantly higher for FG-CCRT than 5FU-CCRT (ORR-32.6% versus 5%; p=0.013; DCR-79.8% versus 50.0%; p=0.006). Both groups showed similar loco-regional control rate (92.2% versus 85.0%; p=0.362) but distant metastasis rate was higher in 5FU-CCRT (17.8% versus 45.0%; p=0.017). Grade 3 or higher neutropenia (34.4% versus 10%; p=0.031) and thrombocytopenia (21.1% versus 0%; p=0.021) was more frequent in FG-CCRT. The subgroup of FG-CCRT patients who received gemcitabine monotherapy showed no significant differences in toxicity rate compared with 5FU-CCRT (all p>0.05). Conclusion: Full-dose gemcitabine based CCRT seems more effective on initial local and distant control of LAPC than bolus 5-FU based CCRT. With cautious monitoring on hematologic toxicities, FG-CCRT can be tolerably conducted. Considering that distant metastasis is one of treatment failure pattern in CCRT of LAPC, full-dose gemcitabine CCRT should be considered as the first line treatment.