Mateusz Szczupak ¹ Jacek Kobak ² Anna Wiśniewska ³ Justyna Kosydar-Bochenek ⁴ Sabina Krupa-Nurcek ^5*

• ¹ Department of Anesthesiology and Intensive Care, Copernicus Hospital, Gdańsk, Poland, Gdansk, Poland
• ² Department and Clinic of Otolaryngology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
• ³ Department of Neurology, Copernicus Hospital, Gdańsk, Poland, Gdańsk, Poland
• ⁴ Institute of Health Sciences, Faculty of Medicine, University of Rzeszow, Rzeszow, Podkarpackie Voivodeship, Poland
• ⁵ College of Medical Sciences, University of Rzeszow, Rzeszow, Podkarpackie Voivodeship, Poland

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological inflammatory disease of paraneoplastic, parainfectious or idiopathic origin. It is manifested by the occurrence of opsoclonus, myoclonus, ataxia, as well as behavioral and sleep disorders. The incidence is estimated at 1/5,000,000 people. This syndrome is usually immune-mediated and may be the first manifestation of cancer as a paraneoplastic syndrome, most often occurring in the course of breast, ovarian or lung cancer. Here we show a case of a 20-year-old woman with symptomatic opsoclonus-myoclonus syndrome in the course of teratoma. A brief review of the literature was conducted to determine the diagnostic route and treatment of this rare condition. As a result, it has been shown that the only method of treatment for OMS syndrome is the removal of the neoplastic lesion.• In the available literature, no other way of treating OMS syndrome has been found other than surgical treatment of tumor removal.• Untreated OMS can cause sleep and behavioral disorders, which in turn can contribute to the development of complications from the nervous system and the need for treatment in a psychiatric clinic.