[Paraneoplastic opsoclonus-myoclonus syndrome revealing T-cell lymphoma].

BACKGROUND: Nonrhythmic involuntary ocular oscillations and axial and segmentary myoclonia are associated in the opsoclonus-myoclonus syndrome. In adults, a paraneoplastic origin is generally found. We report the first of opsoclonus-myoclonus associated with non-Hodgkin's lymphoma.

CASE REPORT: A 66-year-old woman rapidly developed a typical opsoclonus-myoclonus syndrome within a few hours, presenting vertigo, cerebellous ataxia, multidirectional involuntary ocular movements and non-rhythmic axial and segmentary myoclonia. Brain computed tomography and magnetic resonance imaging demonstrated discrete diffuse anomalies of the white substance predominating in the pons. The cerebrospinal fluid showed discrete lymphocytosis. Antineuron antibodies were negative. No cause could be identified until the development 11 months later of pleomorphic T-cell mediastino-cervical lymphoma. The patient responded moderately to a CHOP regimen which had no effect on the opsoclonus-myoclonus syndrome. Death occurred after a 16-month course due to pulmonary complications.

DISCUSSION: Neuroblastoma and infectious causes predominate in opsoclonus-myoclonus syndromes observed in children; in adults, the predominant cause is cancer. Antineuron, anti-Ri and anti-Hu antibodies can be evidenced in some cases, arguing in favor of a paraneoplastic mechanism. Recent reports have evidenced MRI anomalies in the pons and the cerebellum, anatomically well correlated with the opsoclonus-myoclonus syndrome. Besides small-cell bronchogenic anaplastic cancer, the possibility of cancer of the breast and uterus, and both non-Hodgkin and Hodgkin lymphoma should be explored, knowing the cancer develops several month after the opsoclonus-myoclonus syndrome.