Acute mastoiditis with facial paralysis as initial symptom of acute myeloid leukemia relapse: a rare case report

Extramedullary involvement of leukemia usually occurs in the skin and central nervous system. Isolated leukemic involvement of the temporal bone is a very uncommon situation, and it is seen frequently concomitant to hematologic or molecular relapse. An 8-year-old male with acute myeloid leukemia (AML) M2 with t (8,21) (FAB classification) in remission for 2 years was referred to our clinic with severe ear pain, persistent ear discharge, and hearing loss with left facial paralysis for 4 days. Physical examination revealed purulent ear discharge with severe edema of the left ear canal. The temporal computed tomography revealed otomastoiditis. However, temporal magnetic resonance imaging demonstrated a 9 × 6 × 5 mm contrast-enhancing lesion in the internal acoustic canal and thickening in VIIth and VIIIth cranial nerves. Mastoidectomy was performed for exploration and biopsy. The histopathological results of the mastoid bone and soft tissue samples revealed a relapse of AML. One month after the first chemotherapy regime, ear discharge stopped and facial palsy recovered totally. However, the patient died 9 months after the diagnosis of relapse. Temporal bone relapse should be suspected in AML patients with symptoms of otomastoiditis and facial palsy. Further investigations including radiological examinations, surgery, and biopsy for avoiding misdiagnosis and delay in treatment are needed.