title: Mature and immature teratoma: A report from the second Italian pediatric study.
abstract: BACKGROUND
  Teratomas demonstrate a benign clinical behavior, however they may recur with malignant components or as teratoma, and in a small group of patients prognosis could be fatal. After the first Italian study, we collected cases of teratoma, alongside the protocol for malignant germ cell tumors.
  
  
  METHODS
  Patients with teratoma were collected from 2004 to 2014. Teratomas were classified according to the WHO classifications, as mature and immature. Patients with pathological aFP and/or bHCG, and those with a malignant germ cell component were not included.
  
  
  RESULTS
  The study enrolled 219 patients (150 mature, 69 immature teratomas) with a median age at diagnosis of 42 months. The primary sites involved were: 118 gonadal and 101 extragonadal teratomas. Two females with ovarian teratoma had a positive family history. Complete and incomplete surgeries were performed in 85% and 9% of cases. Seventeen events occurred: six females had a second metachronous tumor (5 contralateral ovarian teratoma, 1 adrenal neuroblastoma) and 11 teratomas relapsed/progressed (3 mature, 8 immature teratomas). Two patients died, one of progressive immature teratoma and one of surgical complications. At a median follow up of 68 months, the event-free, relapse-free, and overall survival rates were 90.6%, 94.3%, 98.6%, respectively.
  
  
  CONCLUSIONS
  Teratomas show a good prognosis, especially the mature ones: surgery and follow-up remain the standard approach. Incomplete surgery in immature teratoma is the group at greatest risk of relapse. Bilateral ovarian tumors are a possibility, and the rare family predisposition to ovarian mature teratoma warrants further analyses.
authors: Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: Monica
authors: M
authors: Terenziani
authors: ARNAS Civico, Ospedale Di Cristina e Benfratelli, Palermo, Italy.
authors: Paolo
authors: P
authors: D'Angelo
authors: Ospedale Pediatrico IRCCS Bambino Gesù, Roma, Italy.
authors: Alessandro
authors: A
authors: Inserra
authors: Ospedale Pediatrico IRCCS Bambino Gesù, Roma, Italy.
authors: Renata
authors: R
authors: Boldrini
authors: University Hospital, Padova, Italy.
authors: Gianni
authors: G
authors: Bisogno
authors: Azienda Ospedaliera, Padova, Italy.
authors: Gian Luca
authors: GL
authors: Babbo
authors: Ospedale Giannina Gaslini, Genova, Italy.
authors: Massimo
authors: M
authors: Conte
authors: University Hospital, Padova, Italy.
authors: Patrizia
authors: P
authors: Dall' Igna
authors: Ospedale Pediatrico IRCCS Bambino Gesù, Roma, Italy.
authors: Maria Debora
authors: MD
authors: De Pasquale
authors: Seconda Università, Napoli, Italy.
authors: Paolo
authors: P
authors: Indolfi
authors: Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: Luigi
authors: L
authors: Piva
authors: Ospedale dei Bambini V. Buzzi, Milano, Italy.
authors: Giovanna
authors: G
authors: Riccipetitoni
authors: Policlinico Universitario P. Giaccone, Palermo, Italy.
authors: Fortunato
authors: F
authors: Siracusa
authors: Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy.
authors: Filippo
authors: F
authors: Spreafico
authors: Istituto IRCCS Burlo Garofalo, Trieste, Italy.
authors: Paolo
authors: P
authors: Tamaro
authors: University Hospital, Padova, Italy.
authors: Giovanni
authors: G
authors: Cecchetto
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007558:Italy / Q000453:epidemiology; D008297:Male; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D009447:Neuroblastoma / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D010051:Ovarian Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate; D013724:Teratoma / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D013736:Testicular Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology; D055815:Young Adult
keywords: childhood; germ cell tumors; immature teratoma; mature teratoma