What happened, in summary

A 63-year-old woman was repeatedly hospitalized in late 2019 with severe hyponatremia caused by SIADH. Further investigation found a right upper-lung lesion, and biopsy diagnosed limited-disease small cell lung cancer. She received cisplatin and etoposide with radiation from January through April 2020. The cancer showed a good partial remission, and her sodium levels also improved for several months. Later in 2020, severe hyponatremia returned. Imaging then showed new lung nodules, multiple liver lesions, and a pancreatic lesion; a liver biopsy confirmed metastatic small cell lung cancer. She received palliative atezolizumab with carboplatin and etoposide. Her SIADH became increasingly difficult to control and required repeated hospital care, including tolvaptan and other supportive measures. Serial scans showed further progression of the metastatic cancer, especially in the liver. She died from disseminated liver metastases and liver failure in February 2021.