Background: An accessory pelvic spleen is rare and may be misdiagnosed as an adnexal tumor.Case Report: An 18-year-old nulliparous woman was referred from a clinic with a finding of left adnexal mass during induced abortion. Transvaginal ultrasonogram demonstrated a left adnexal tumor. Exploratory laparotomy was performed. There were 2 cystic masses in the left pelvic cavity. The masses were excised and their histopathology revealed normal splenic tissue. She was well at discharge and throughout the 4-week of follow-up period.Conclusions: Although accessory pelvic spleen is uncommon, it should be included in the differential diagnosis of adnexal masses. Removal of the accessory pelvic spleen is recommended under all instances.

Keywords: Accessory spleen, pelvic, adnexal mass