Multiple Cranial Neuropathies as the Presenting Sign in a Patient with Metastatic BRAF-Mutated Lung Adenocarcinoma with Leptomeningeal Involvement.

Leptomeningeal carcinomatosis accounts for only 4% of cases of multiple cranial neuropathies. Here, we report the case of a patient who presented with multiple synchronous cranial neuropathies. After treatment for neuroborreliosis and broad infectious workup, endobronchial ultrasound-guided mediastinal lymph node biopsy confirmed a diagnosis of metastatic BRAF-mutated lung adenocarcinoma with leptomeningeal involvement.