Randomized phase III study of S-1 alone versus S-1 plus lentinan for unresectable or recurrent gastric cancer

Authors: Shigefumi Yoshino, Kazuhiro Nishikawa, Satoshi Morita, Tsuyoshi Takahashi, Koichiro Sakata, Jiro Nagao, Hiroshi Nemoto, Nozomu Murakami, Takeru Matsuda, Hiroyasu Hasegawa, Ryoichi Shimizu, Takaki Yoshikawa, Hiroyuki Osanai, Motohiro Imano, Hiroshi Naitoh, Akiyoshi Tanaka, Takashi Tajiri, Akira Gochi, Michinari Suzuki, Junichi Sakamoto, Shigetoyo Saji, Masaaki Oka

Journal: European Journal of Cancer

Study Design: Prospective, multicentre, randomised, open-label phase III clinical trial

Participants: 309 patients with histologically proven, unresectable or recurrent gastric cancer

Intervention: The patients were randomly assigned to two groups:

• S-1 alone group (n=154)
• S-1 plus LNT group (n=155): Received S-1 plus lentinan (LNT) as an intravenous infusion of 2 mg/body every week.

Outcome Measures:

• Primary endpoint: Overall survival (OS)
• Secondary endpoints: Time-to-treatment failure (TTF), overall response rate (ORR), safety, quality of life (QOL), and biomarker.

Summary: The study investigated the efficacy of LNT in combination with S-1 as a first-line treatment for unresectable or recurrent gastric cancer. The results showed that the addition of LNT to S-1 did not improve overall survival and was associated with a significantly worse time-to-treatment failure. The overall response rates and safety profiles were similar between the two groups. The study concluded that LNT did not provide additional benefit when combined with S-1 in this patient population. Additionally, in a subpopulation of patients with LNT-binding monocytes ≥2%, those who received more than two cycles of chemotherapy showed a longer survival time in the S-1 plus LNT group compared to the S-1 group, suggesting a potential predictive biomarker for LNT efficacy.