The HER2 positive advanced or metastatic gastric cancer (GC) is recommended with Trastuzumab (Tmab) combined cisplatin (CDDP) and capecitabine (Cap). Otherwise, oxaliplatin (L-OHP) has been replaced in place of CDDP for GC. Furthermore, S-1 is a key oral anticancer drug used in the treatment of gastrointestinal cancer in Asia. A 59- year-old man who received Tmab-SOX therapy for solitary synchronous liver metastasis of GC, because the operated intestinal type GC revealed HER2 score 3+ immunohistochemically. Tmab-SOX: (Tmab: 8 mg/kg for first cycle, 90minutes (mins) and 6 mg/kg for subsequent cycles on day 1, 30 mins, L-OHP: 100 mg/m2, day 1, 120 mins, S-1: 80 mg/m2 twice daily, days 1 to 15, orally, every 3 weeks). The solitary liver metastasis shrunk from 28 mm to 13 mm, 4 cycles later. We performed right lobe hepatectomy which specimens’ revealed pathological complete response. Tmab-SOX therapy proved remarkable response and might be an alternative chemotherapy plan against HER2 positive GC.
Hiroshi Osawa, Kenji Yamada, Yoko Kuroda and Hisako Endo