Adjuvant TRastuzumab Deruxtecan for HER2-positive Gastroesophageal Cancer With Persistence of miNImal Residual Disease

6 cycles of: T-DXd at the dose of 6.4 mg/kg intravenous every 3 weeks plus capecitabine 1000 mg/sqm BID orally on days 1-14 every 3 weeks or 5-fluorouracil 600 mg/m2/day continuous intravenous infusion on days 1-5 every 3 weeks as per Investigator's choice

4 cycles of: 5-fluorouracil 2600 mg/m2 continuous intravenous infusion day 1 for 24 hours every 2 weeks, leucovorin 200 mg/m2 intravenous infusion on day 1 every 2 weeks, oxaliplatin 85 mg/m2 intravenous infusion on day 1 every 2 weeks, and docetaxel 50 mg/m2 intravenous infusion on day 1 every 2 weeks.