A phase II study of S-1 and oxaliplatin (SOx) combination chemotherapy as a first-line therapy for patients with advanced gastric cancer.
BACKGROUND
Palliative chemotherapy has been shown to have a survival benefit for patients with recurrent or metastatic gastric cancer. 5-fluorouracil (5-FU) and cisplatin have been widely used in a variety of combinations. We conducted a phase II study of combination chemotherapy with new agents, S-1 and oxaliplatin (SOx), in advanced gastric cancer patients in an effort to evaluate the efficacy and toxicity of this regimen.


METHODS
Histologically confirmed recurrent or metastatic gastric cancer were treated by the oral administration of S-1 80 mg/m(2)/day on days 1-28, and oxaliplatin 85 mg/m(2) administered as a 90-min intravenous infusion on days 1, 15, and 29. Treatment courses were repeated every 6 weeks. Patients received a maximum of four cycles.


RESULTS
From Feb 2006 to May 2008, 41 patients were enrolled in this study. The ratio of males to females was 28 to 13. The median patient age was 61 years (range, 36-74 years), and 85.4% (35/41) of the patients had a performance status (ECOG) of 1. The median number of chemotherapy cycles administered was 3 (range, 1-4). According to the results of our Intent-to-Treat analysis, 22 patients (53.7%) achieved a partial response (95% CI, 38-70%). 15 patients (36.6%) evidenced a stable disease, and 1 patient (2.4%) progressed during the course of the treatment. 3 patients were lost to follow-up prior to evaluation. The median time to progression and overall survival time were 4.6 months (95% CI, 3.4-5.8 months) and 7.8 months (95% CI, 6.9-8.7 months) from the start of the chemotherapy, respectively. A total of 114 cycles were assessed for toxicity. The major hematologic toxicities included grade 2 anemia (41.2%), grade 1-2 neutropenia (28.1%), and grade 1 thrombocytopenia (23.7%). Only 1 cycle of neutropenic fever occurred. The non-hematological toxicities observed were grade 3 vomiting (12.2%) and grade 3 diarrhea (4.9%). No treatment-related deaths occurred in our patient population during the study period.


CONCLUSIONS
The SOx regimen evidenced a relatively high response rate and was well tolerated as a first-line therapy for advanced gastric cancer.
Oh
Sung Yong
SY
Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea.
Kwon
Hyuk-Chan
HC
Jeong
Sang-Ho
SH
Joo
Young-Tae
YT
Lee
Young-Joon
YJ
Cho
Su hee
Sh
Kang
Myoung Hee
MH
Go
Se-il
SI
Lee
Gyeong-won
GW
Kim
Hoon gu
Hg
Kang
Jung Hun
JH
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D004334:Drug Administration Schedule; D004338:Drug Combinations; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D000077150:Oxaliplatin; D010094:Oxonic Acid / Q000008:administration & dosage; D011446:Prospective Studies; D056910:Republic of Korea; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D005641:Tegafur / Q000008:administration & dosage; D013997:Time Factors; D016896:Treatment Outcome
D004338:Drug Combinations; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid