Ovarian dermoid cyst, also known as benign mature teratoma, originate from germ cells in the ovary, and is the most common benign ovarian tumor (44-70%). Several reports documented a secretion of NMDA receptor antibodies from dermoid cyst. This receptor is found in different areas in the central nerves system (CNS) and the presence of plasma antibodies has been shown as a rare cause of neurologic presentation term paraneoplastic neurologic syndrome, which can be characterized by mood disorder, psychiatric and neurologic symptoms. In several case reports on young women, first presented with nonspecific neurologic symptoms, then followed by rapid deterioration of conscious, seizures and the need for ventilation support, ovarian teratoma was diagnosed. In 2007 an association between N-Methyl-D-Aspartic acid (NMDA) receptor antibody and encephalitis was first described. More than 50% of paraneoplastic encephalitis were related to teratomas, most often from an ovarian origin. Therapy includes tumor resection, steroids, plasmapheresis and immunosuppressive drugs. The investigators recently published a retrospective cohort study analyzing 233 patients who were operated in their institution with pathology proven dermoid. In this study 2 patients presented with paraneoplastic syndrome (0.85%). No prospective study has been published to date to examine the association between antibody titer and dermoid cyst characteristics and the paraneoplastic phenomenon. The investigators wish to conduct a prospective study in which plasma samples will be obtained from patients asymptomatic for neurologic or psychiatric symptoms, undergoing surgery for ovarian dermoid cyst, due to gynecology indication (e.g size, symptoms) in order to identify antibodies against CNS NMDA-R in their plasma prior to cyst removal. If NMDA receptor antibodies will be discovered in asymptomatic patients it may be prudent to examine all serums of women who are diagnosed with ovarian mature teratoma, and offer a surgical removal in order to prevent a possible neurologic sequela in the presence of these antibodies.

The data is collected by examining women's serum for the presence of NMDA-R antibodies, using special ELISA (enzyme-linked immunoabsorbent assay) kits. The analysis will be made by Dyn diagnostics labs. The investigators will obtain a blood sample prior to the operation for cystectomy or oophorectomy and after a written informed consent by the patient. All specimen are sent to pathology examination and only proven dermoid cyst will eventually be enrolled.

Inclusion Criteria:

1. Women admitted for surgery for removal of suspected dermoid cysts
2. No neurologic symptoms

Exclusion Criteria:

1. No surgical specimen available
2. The cyst pathology does not show dermoid cyst characteristics

women in reproductive years

women in reproductive years undergoing cystectomy or oopherectomy due to suspected ovarian dermoid cyst