Paraneoplastic opsoclonus myoclonus syndrome is most commonly associated with which malignancy in children?: (A) Hepatoblastoma, (B) Hepatocellular carcinoma, (C) Lymphoma, (D) Neuroblastoma
Answer is D. Opsoclonus is a disorder of eye movement characterized by involuntary, chaotic saccades that occur in all directions of gaze; it is frequently associated with myoclonus and ataxia. Opsoclonus-myoclonus may be cancer-related or idiopathic. When the cause is paraneoplastic, the tumors involved are usually cancer of the lung and breast in adults and neuroblastoma in children. Ref: Harrison's principle of internal medicine 17th edition, chapter 97.