Practical Consensus Guidelines for the Use of S-1 in GI Malignancies

Purvish M Parikh S-1 (5-fluorouracil prodrug [tegafur] in combination with 5-chloro-2,4-dihydroxypyridine [CDHP] and potassium oxonate [OXO]) was first approved in 1999. In order to make it easy for community oncologists, we decided to put together this expert consensus guideline for its use in gastrointestinal (GI) malignancies. A total of 15 subject matter experts used modified Delphi method to discuss, analyze, and vote on key aspects regarding practical approach to use of S-1 in GI cancers, a process involving 6 months of work. The consensus guidelines specify how S-1 use can be optimized in patients with colorectal, gastric, and pancreatic tumors. The voting for the 17 key points resulted in a majority consensus for all the statements (approval ranging from 13/15 [87%] to 15/15 [100%]). S-1 is a combination of three drugs (tegafur, CDHP, and OXO) specifically designed to reduce toxicity and enhance efficacy; clinical data and meta-analysis confirm both factors; and it is recommended as standard of care for GI cancers. S-1 is approved and one of the standards of care for all lines of therapy in colorectal cancer and pancreatic cancers. S-1 with oxaliplatin is the standard of care for gastric cancers.