AQP4 and myeloid sarcoma: Only 3 out of 57 patients (5.3%) who had no supratentorial lesions at first examination, and 5 out of 34 (14.7%) patients who had non-MS specific supratentorial lesions developed lesions classified as "compatible with the diagnosis of MS" later in the disease course; AQP4-Ab were positive in all of these cases.