Cerebral venous sinus thrombosis concomitant with leptomeningeal carcinomatosis, in a patient with epidermal growth factor receptor-mutated lung cancer

A 64-year-old woman presented with dizziness, after two weeks of experiencing symptoms. Chest computed tomography revealed a peripheral nodule in her left upper lobe, and brain magnetic resonance imaging (MRI) demonstrated the presence of multiple brain masses. The patient underwent whole-brain radiotherapy based on a tentative diagnosis of lung cancer with multiple brain metastases. The diagnosis was confirmed by endobronchial biopsy as T4N3M1b, stage IV lung adenocarcinoma with an epidermal growth factor receptor mutation. On the 31st day of hospitalization, the patient developed severe headache. Subsequent magnetic resonance venography revealed defects in the superior sagittal, right sigmoid, and right transverse venous sinuses and the right internal jugular vein. Anticoagulation therapy with unfractionated heparin and warfarin was immediately administered following diagnosis of cerebral venous sinus thrombosis (CVST). Brain MRI demonstrated leptomeningeal gadolinium enhancement in front of the pons and medulla. Positive cerebrospinal fluid tumor cytology confirmed the diagnosis of leptomeningeal carcinomatosis. Following four weeks of antithrombotic therapy, complete thrombolysis was confirmed by magnetic resonance venography. Effective treatment with gefitinib was administered, and the patient survived for 10 months after the diagnosis of CVST and leptomeningeal carcinomatosis. Adequate early diagnosis and treatment of CVST enabled an excellent survival rate for the patient, despite leptomeningeal carcinomatosis. Following the development of headaches in patients with lung cancer, CVST, although rare, should be considered. Furthermore, following a diagnosis of CVST, leptomeningeal carcinomatosis should be investigated as an underlying cause.