Dramatic Response to Alectinib in a Critically Ill Elderly Patient with Lung Adenocarcinoma Due to Trousseau Syndrome and Disseminated Intravascular Coagulation.

Lung cancer complicated with Trousseau syndrome (TS) or disseminated intravascular coagulation (DIC) has a severe prognosis. We herein report an elderly lung cancer patient who presented with a critically ill condition due to concomitant TS and DIC and responded dramatically to alectinib. There are no rules regarding treatment indications based on the age or severity of critically ill patients. If the patient's cancer cells are positive for anaplastic lymphoma kinase rearrangement, alectinib is worthwhile to administer, even in a critically ill condition. In our patient, anticoagulation failed to suppress the TS complications. We also report how to prevent the recurrence of TS.