Successful Treatment of a Patient with HER2-Positive Metastatic Gastric Cancer with Third-Line Combination Therapy with Irinotecan, 5-Fluorouracil, Leucovorin and Trastuzumab (FOLFIRI-T)

Background: For patients with HER2-overexpressing gastric cancer, there is an improved prognosis with additional trastuzumab to chemotherapy with a platinum compound and a fluoropyrimidin in first-line therapy. Second-line combinations are currently evaluated in various studies. Case Report: We report the case of a 43-year-old male patient who came to our hospital with recurrent metastatic gastric cancer after curative surgery 18 months before. His disease responded well to several therapeutic regimens. First-line chemotherapy with a combination of epirubicin, oxaliplatin and capecitabine (EOX) and the following therapies - peritonectomy, multi-visceral resection, hyperthermic intraperitoneal chemotherapy (HIPEC), and second-line chemotherapy with oxaliplatin, 5-fluorouracil and leucovorin (FLO) - induced a complete remission. At the time of the subsequent progression, HER2 overexpression was detected. We administered the combination of irinotecan, 5-fluorouracil, leucovorin (FOLFIRI) and trastuzumab, which to our knowledge was used for the first time in a patient with metastatic gastric cancer in third-line therapy. This regimen again induced a complete remission of the disease, which has been sustained now for at least 8 months. Conclusion: This is the first time in the literature that a combination of FOLFIRI and trastuzumab (FOLFIRI-T) was used successfully in a patient with recurrent metastatic gastric cancer.