641P - Phase II multi-institutional prospective randomized trial comparing S-1 + paclitaxel with paclitaxel alone as second-line chemotherapy in patients...

Date 29 September 2014
Event ESMO 2014
Session Poster Display session
Topics Anti-Cancer Agents & Biologic Therapy
Gastric Cancer
Presenter Kouki Nakanishi
Citation Annals of Oncology (2014) 25 (suppl_4): iv210-iv253. 10.1093/annonc/mdu334
Authors K. Nakanishi1, D. Kobayashi2, Y. Mochizuki3, K. Ishigure4, S. Ito5, H. Kojima6, A. Ishiyama7, S. Fujitake8, T. Shikano9, Y. Kodera10
  • 1Surgery, Komaki Municipal Hospital, 4858520 - Komaki/JP
  • 2Gastroenterological Surgery, Nagoya University Graduate School of Medicine, 4668550 - Nagoya/JP
  • 3Surgery, Komaki Municipal Hospital, Komaki/JP
  • 4Department Of Surgery, Konan Kosei Hospital, Konan/JP
  • 5Gastroenterological Surgery, Aichi Cancer Center, 4648681 - Nagoya Aichi/JP
  • 6Gastroenterological Surgery, Aichi Cancer Center Aichi Hospital, Okazaki Aichi/JP
  • 7Department Of Surgery, Okazaki City Hospital, Okazaki/JP
  • 8Surgery, Nishio Municipal Hospital, Nishio/JP
  • 9Surgery, Yokkaichi Municipal Hospital, Yokkaichi/JP
  • 10Gastroenterological Surgery, Nagoya University Graduate School of Medicine, Nagoya/JP



In Japan, S-1 has been the key drug in the first-line treatment for gastric cancer. However, there has been no evidence in support of continuation of S-1 in combination with another anticancer drug in the second-line setting. A multicenter randomized phase II trial was conducted to explore whether continuation of S-1 in addition to paclitaxel, a drug often used alone in the second-line setting, offers any benefit to the patients.


Gastric cancer patients who showed progression during the S-1-based first-line chemotherapy or has recurrence during the postoperative adjuvant treatment by S-1 were randomly assigned to the second-line treatment either by weekly administration of paclitaxel (PTX) at 80 mg/m2 three times every 4 weeks or daily oral S-1 (80 mg/m2) for 2 weeks plus paclitaxel (50 mg/m2) given on days 1 and 8, every 3 weeks (S-1 + PTX). Primary end points were the progression-free survival (PFS) at 4 months and the incidence of adverse effects. Secondary end points included response rate and overall survival (OS).


A total of 79 patients were eligible for efficacy analyses, 38 of whom were randomized to the S-1 + PTX group and 41 to the PTX group. PFS at 4 months was similar between the groups (45% for S-1 + PTX vs 49% for PTX, P = 0.71). The incidences of grade 3 or more haematological and non-haematological toxicities were also equivalent between the groups (21% vs 22% and 24% vs 27%, respectively). Although there were no statistically significant differences, the median OS was longer in the S-1 + PTX group (463 days vs 312 days, P = 0.46). Response rate was similar between the groups (22% for S-1 + PTX vs 29% for PTX, P = 0.75). The proportion of patients who remain progression-free for more than 300 days was higher among the S-1 + PTX group in a subset of patients who had relapse during the postoperative adjuvant chemotherapy (31% vs 7%).


Neither benefit nor shortcomings of S-1 administration beyond progression was proven when paclitaxel was selected as a second-line chemotherapy. S-1 + paclitaxel could be considered for patients who relapsed during postoperative adjuvant therapy by S-1.


All authors have declared no conflicts of interest.