[A case of renal salt-wasting syndrome during chemotherapy for advanced gastric cancer].

A 66-year-old woman was admitted to our hospital with heartburn and liver dysfunction. She was diagnosed with advanced gastric cancer. After the initiation of chemotherapy with trastuzumab, capecitabine, and cisplatin, she developed hyponatremia and renal failure with renal salt-wasting syndrome (RSWS). She recovered from these conditions after infusion of hypertonic saline. A diagnosis of RSWS should be considered in patients with hyponatremia who receive cisplatin-based chemotherapy.