[A case of small-cell lung carcinoma accompanied by the syndrome of inappropriate secretion of antidiuretic hormone and Lambert-Eaton myasthenic syndrome].

Although the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and Lambert-Eaton myasthenic syndrome (LEMS) are often individually accompanied by small-cell lung carcinoma, simultaneous occurrence of the 2 syndromes is rare. A 61-year-old man was admitted to our hospital because of fatigue and myasthenia in the extremities, and small-cell lung carcinoma with pulmonary metastasis was diagnosed, together with SIADH and LEMS. These syndromes markedly ameliorated following tumor shrinkage, with 4 cycles of chemotherapy consisting of carboplatin and etoposide. On progression of the tumor thereafter, neither syndrome recurred. A literature review disclosed that these syndromes frequently resolve with tumor shrinkage.