[Harlequin syndrome (unilateral flushing and sweating attack) due to a spinal invasion of the left apical lung cancer].

A 54-year-old man was admitted to our hospital because of a persistent pain of the left cervix and scapular region of three-month duration and an abnormal shadow in the chest roentgenograms. Neurological examinations, chest roentgenograms, chest CT scanning, vertebral tomograms and myelogram revealed Pancoast's syndrome concomitant with Horner's syndrome. Four months later, the patient complained of a sudden onset of unilateral flushing and sweating appearing on the right face, cervix and upper chest. Eye drop tests with cocaine, epinephrine and tyramine indicated the lesion of ciliospinal centers between the 8th cervical and 2nd thoracic spines. The unilateral flushing and sweating attack appearing on the intact side without Horner's syndrome seemed to be an excessive response by an intact sympathetic pathway, the other side failing to respond because of a sympathetic deficit.