title: Retroperitoneal mass with ischiorectal fossa extension: diagnosis, clinical features and surgical approach. A literature review starting from a rare clinical case of primary retroperitoneal dermoid cyst.
abstract: BACKGROUND
  Primary retroperitoneal teratomas are rare and occur mostly in the sacrococcygeal area of children. They constitute less than 4% of all extragonadal teratomas with less than 120 cases having been reported, and only partly described in the retroperitoneum of adults. We describe an unusual case of a paravescical teratoma with ischio-rectal extension and its successful surgical management.
  
  
  METHODS
  A 24-year-old female was referred to our hospital with a history of pelvic pain, pressure and evidence of a pelvic-perineal tumor. Serial work-up disclosed a mass in the left paravesical fossa that bulged out through the levator-ani muscle, in the left ischial-rectal fossa, altering the symmetry of the gluteal/perineal region. At surgery a cystic tumor, consistent with a dermoid, was completely excised from the left paravesical fossa by means of a laparotomic approach. Pathological examination revealed a mature cystic teratoma. The postoperative course was smooth and the patient was doing well at two-year followup.
  
  
  CONCLUSIONS
  This is the second reported case of paravesical dermoid cyst with ischio-rectal extension through the levator-ani muscle. Retroperitoneal teratomas are rare and difficult to early diagnose because of non specific signs and symptoms and should be considered in the differential diagnosis of a pelvic mass in adults. Solid and cystic morphology, fat signal and areas of calcification are some of the helpful features in diagnosing this neoplasia. Once the diagnosis is made, surgical removal is indispensable because of the indeterminate course of the disease. Prognosis depends on the histologic nature of teratoma. Patients with complete resection of benign teratoma have an excellent prognosis. Malignant teratomas, either with germ cell elements or with somatic elements, have a poor outcome.
authors.affiliation: Department of Obstetrics and Gynecology, University of Ljubljana, Ljubljana, Slovenia.
authors.forename: A
authors.initials: A
authors.lastname: Lukanovic
authors.forename: T S
authors.initials: TS
authors.lastname: Patrelli
mesh_terms: D000328:Adult; D003884:Dermoid Cyst / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006801:Humans; D007512:Ischium; D011859:Radiography; D035583:Rare Diseases; D012186:Retroperitoneal Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D012187:Retroperitoneal Space / Q000000981:diagnostic imaging* / Q000601:surgery; D013724:Teratoma / Q000000981:diagnostic imaging* / Q000601:surgery