Case of Syndrome of Inappropriate Antidiuretic Hormone Secretion in a Patient with Esophageal Cancer

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) may be observed in various types of cancer, but is mainly seen in small-cell carcinoma. It can also be caused by several chemotherapeutic agents. However, it is a very rare phenomenon in esophageal cancer or its treatment. We report here on a case of SIADH related to esophageal cancer treatment. A 55-year-old man received chemoradiotherapy (CRT) for esophageal cancer. After receiving CRT for 5 days, he complained of nausea, dizziness, and general weakness, and his sodium level had dropped to 107 mEq/L. His volume status was clinically euvolemic and there were no edema or pigmentation. After hypertonic saline infusion, the sodium level increased and the symptoms improved. There have been several reports of SIADH associated with malignancies or chemotherapy agents. However, to the best of our knowledge, this is the first Korean case of SIADH associated with esophageal cancer that occurred after cisplatin treatment. (Korean J Med 2015;88:231-235)