Phase II study of oral S-1 and concurrent radiotherapy in patients with unresectable locally advanced pancreatic cancer

Int J Radiat Oncol Biol Phys. 2011 May 1;80(1):119-25. doi: 10.1016/j.ijrobp.2010.01.027. Epub 2010 Jun 3.

Abstract

Purpose: S-1 is an oral fluoropyrimidine derivative that has demonstrated favorable antitumor activity in patients with metastatic pancreatic cancer. The aim of this study was to evaluate safety and efficacy of S-1 and concurrent radiotherapy in patients with unresectable locally advanced pancreatic cancer.

Methods and materials: Patients with histopathologically proven, unresectable, locally advanced pancreatic cancer were eligible. Radiotherapy was delivered in 1.8 Gy daily fractions to a total dose of 50.4 Gy over 5.5 weeks. S-1 was administered orally twice a day at a dose of 80 mg/m(2)/day from day 1 to 14 and 22 to 35. Two weeks after the completion of chemoradiotherapy, maintenance chemotherapy with S-1 was administered for 28 days every 6 weeks until progression.

Results: Thirty-four patients were enrolled in this study. The most common Grade 3 toxicities during chemoradiotherapy were anorexia (24%) and nausea (12%). The overall response rate was 41% (95% confidence interval, 25%-58%) and overall disease control rate (partial response plus stable disease) was 97%. More than 50% decrease in serum CA 19-9 was seen in 27 of 29 evaluable patients (93%). The median progression-free survival was 8.7 months. The median overall survival and 1-year survival rate were 16.8 months and 70.6%, respectively.

Conclusions: Oral S-1 and concurrent radiotherapy exerted a promising antitumor activity with acceptable toxicity in patients with locally advanced pancreatic cancer. This combination therapy seems to be an attractive alternative to conventional chemoradiotherapy using 5-fluorouracil infusion.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Anorexia / etiology
  • Antimetabolites, Antineoplastic / adverse effects
  • Antimetabolites, Antineoplastic / therapeutic use*
  • CA-19-9 Antigen / blood
  • Combined Modality Therapy / adverse effects
  • Combined Modality Therapy / methods
  • Deoxycytidine / analogs & derivatives
  • Deoxycytidine / therapeutic use
  • Disease Progression
  • Drug Administration Schedule
  • Drug Combinations
  • Female
  • Gemcitabine
  • Humans
  • Male
  • Middle Aged
  • Nausea / etiology
  • Oxonic Acid / adverse effects
  • Oxonic Acid / therapeutic use*
  • Pancreatic Neoplasms / drug therapy*
  • Pancreatic Neoplasms / mortality
  • Pancreatic Neoplasms / pathology
  • Pancreatic Neoplasms / radiotherapy*
  • Prospective Studies
  • Radiotherapy Dosage
  • Tegafur / adverse effects
  • Tegafur / therapeutic use*

Substances

  • Antimetabolites, Antineoplastic
  • CA-19-9 Antigen
  • Drug Combinations
  • Deoxycytidine
  • S 1 (combination)
  • Tegafur
  • Oxonic Acid
  • Gemcitabine