Pharmacokinetics of TS-1 Administered Through Jejunostomy for Unresectable advanced Remnant Gastric Cancer

Yasuhiro Miyazaki, Hiroshi Imamura, Hiroshi Furukawa, Masayuki Tatsuta, Yukako Yasui¹⁾, Setsuko Anami¹⁾ and Hiroyuki Yasui²⁾

Department of Surgery and Department of Pharmacy¹⁾, Sakai Municipal Hospital
Department of Analytical and Bioinorganic Chemistry, Kyoto Pharmaceutical University²⁾

A 76-year-old man who had undergone proximal gastrectomy and was then diagnosed with severe pyloric ring stenosis from inoperable remnant gastric cancer due to massive local infiltration was treated using gastric and jejunal tubes inserted through a jejunostomy for gastric decompression. On postoperative day (POD) 18, TS-1 was administered as first-line chemotherapy through the jejunal tube. TS-1 pharmacokinetics were then monitored from drug administration on day (DAD) 1. Plasma tegafur (FT), 5-FU, gimeracil (CDHP), and oteracil potassium (Oxo) levels were then measured and adverse effects monitored. The highest plasma FT concentration was 1,920 ng/ml at 30 minutes, of 5-FU 89.2 mg/ml at 2 hours, of CDHP 162.2 mg/ml at 1 hour, and of Oxo 119.6 mg/ml also at 1 hour after TS-1 administration. No grade 3 or 4 adverse events were observed. The primary tumor began shrinking after 2 cycles, and the man has since undergone four regimen cycles. This case suggests that TS-1 administration through a jejunostomy can be continued long-term without adverse events and may be effective in patients unable to ingest oral medication.

Key words
TS-1, administration via jejunostomy, pharmacokinetics

Reprint requests
Yasuhiro Miyazaki Department of Surgery, Sakai Municipal Hospital
1-1-1 Minamiyasui-cho, Sakai, 590-0064 JAPAN

Accepted
June 18, 2009

To read the PDF file you will need Abobe Reader installed on your computer.