Mature Cystic Teratoma Combined With Autoimmune Limbic Encephalitis Mimicking Functional Ovarian Cyst

Autoimmune limbic encephalitis (ALE) associated with an anti-N-methyl-D-aspartate receptor (NMDAR) is a rare but occasionally fatal condition that could be accompanied by ovarian teratoma. We report a case of a 27-year-old woman with ALE combined with a mature cystic teratoma that looks like a functional cyst in imaging studies. A single port access laparoscopic left oophorectomy was performed. On the 154th postoperative day, symptoms were fully recovered. Teratoma detection and tumor removal are critical for the management of patients diagnosed with or suspected of ALE.