[A Patient with HER2-Positive Stage IV Advanced Gastric Cancer Who Received Chemotherapy with Trastuzumab plus XP Followed by Conversion Surgery].

A 68-year-old man presented with type 3 advanced gastric cancer(Circ, tub2>por, HER2 score 3)in the antrum, with skip lesions in the duodenum. The tumor was cT4aN2M1(DUO)CY0, cStage IV . An XP plus trastuzumab regimen(1,000mg/m2 capecitabine[Xeloda®]twice a day on days 1-14, 80mg/m2 CDDP on day 1, 8 mg/m2 trastuzumab on day 1[second course- 6mg/m2])was administered every 3 weeks and repeated for 6 courses without severe adverse events. After 6 courses, the primary tumor and metastatic lymph nodes shrank by 31.7%(a PR according to the RECISTcriteria ), and open distal gastrectomy, D3 lymphadenectomy, and Roux-en-Y reconstruction(ante colic)were performed as conversion surgery(R0). During the administration of adjuvant chemotherapy with S-1, para-aortic, mediastinum, left supraclavicular fossa, and cervical lymph node recurrence developed. Four courses of weekly PTX plus trastuzumab as first-line chemotherapy and 11 courses of biweekly CPT-11 plus CDDP as second-line chemotherapy were administered. Because of prolonged adverse events such as Grade 3 diarrhea, the patient refused continuation of chemotherapy. The patient died 24 months after the start of preoperative chemotherapy.