Kenya Kamimura,1 Yoko Shinagawa-Kobayashi,1 Ryo Goto,1 Kohei Ogawa,1 Takeshi Yokoo,1 Akira Sakamaki,1 Satoshi Abe,1 Hiroteru Kamimura,1 Takeshi Suda,2 Hiroshi Baba,3 Takayuki Tanaka,4 Yoshizu Nozawa,5 Naoto Koyama,6 Masaaki Takamura,1 Hirokazu Kawai,1 Satoshi Yamagiwa,1 Yutaka Aoyagi,1 Shuji Terai1 1Division of Gastroenterology and Hepatology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata, Japan; 2Department of Gastroenterology and Hepatology, Uonuma Institute of Community Medicine, Niigata Medical and Dental Hospital, Minami-Uonuma, Niigata, Japan; 3Division of Anesthesiology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata, Japan; 4Uonuma Eye Clinic, Uonuma, Niigata, Japan; 5Institute of Food Sciences and Technologies, Ajinomoto Co., Inc., Kawasaki, Kanagawa, Japan; 6Institute for Innovation, Ajinomoto Co., Inc., Kawasaki, Kanagawa, Japan Background: Sorafenib (SOR) is a molecular medicine that prolongs the survival of patients with hepatocellular carcinoma (HCC). Therefore, the management of side effects is essential for the longer period of continuous medication. Among the various side effects, hand–foot syndrome (HFS) is the most common, occurring in 30%–50% of patients, and often results in discontinuation of the SOR medication. However, its mechanism has not been clarified, and no effective prevention method has been reported for the symptoms. Therefore, this study aimed to analyze its mechanism and to develop an effective prevention regimen for the symptoms. Materials and methods: To assess the mechanism of SOR-induced HFS, the peripheral blood flow in the hand and foot was carefully monitored by Doppler ultrasound, thermography, and laser speckle flowgraphy in the cases treated with SOR and its contribution was assessed. Then, the effect of dried-bonito broth (DBB), which was reported to improve peripheral blood flow, on the prevention of the symptom was examined by monitoring its occurrence and the peripheral blood flow. Results: A total of 25 patients were enrolled in this study. In all, eight patients developed HFS, and all cases showed a significant decrease in the peripheral blood flow. DBB contributed to an increase in the flow (p = 0.009) and significantly decreased occurrence of HFS (p = 0.005) than control. Multivariable analysis showed that the ingestion of DBB is a significant independent contributor to HFS-free survival period (p = 0.035). Conclusion: The mechanism of SOR-induced HFS involves a decrease in the peripheral blood flow, and the ingestion of DBB effectively prevents the development of the syndrome by maintaining the flow. Keywords: sorafenib, hepatocellular carcinoma, hand–foot syndrome, blood flow, bonito broth
