Tumor-forming acute myeloid leukemia with facial paralysis.

A 55-year-old male with acute myeloid leukemia, which had been well controlled for 2 years, developed a sudden onset of facial palsy. Otologic examinations proved the right mastoid bone to be infiltrated by leukemic cells, which formed a nonchloroma to occlude the right external auditory canal. The precise site for the right facial paralysis by tumor formation was found in the intrastapedial region of peripheral portion of the right facial nerve. Regarding the tumor formation in myeloid leukemia, its frequency (particularly among Japanese subjects), complications (particularly in otologic field), possible pathogeneses, and treatments were discussed.