title: Two Tumors in 1: What Should be the Therapeutic Target? Pediatric Germ Cell Tumor With Somatic Malignant Transformation.
abstract: Germ cell tumors with somatic malignant transformation (GCT with SMT) are rare in children and poorly described. Data are missing to determine if therapies should target the GCT, the SMT compound, or both simultaneously.
  
  
  
  A retrospective national study was conducted in the Société Française des cancers de l'Enfant (SFCE) Centers. Medical records from patients aged 0 to 18 years diagnosed with GCT with SMT between 2000 and 2015 were analyzed. Any stages and primary sites were considered as well as synchronous and metachronous cases.
  
  
  
  Fifteen patients were identified. Thirteen patients had synchronous GCT with SMT. In the latter cases, primaries were ovary (5), mediastinum (3), pineal gland (3), sacrococcyx (1), and parametrium (1). SMT histologies were central primitive neuroectodermal tumor (5), embryonal rhabdomyosarcomas (3) or thyroid papillary adenocarcinoma, leukemia, poorly differentiated carcinoma, mixed sarcomas, and miscellaneous histology (1 case each). Chemotherapy was targeted against the GCT (3), the SMT (6), or both components (3). The last patient received surgery exclusively. Partial or complete response to chemotherapy was observed in 5/10 assessable cases: 2/3 patients treated with GCT-dedicated chemotherapy, 3/6 patients treated with SMT-dedicated therapy, and 0/1 treated with combined therapy. In addition, 2 patients with mediastinal GCT primary had metachronous SMT, with acute myeloid leukemia and thyroid papillary adenocarcinoma, 8 months and 8 years, respectively, after the diagnoses of GCT. Two patients (1 synchronous and 1 metachronous) were cured with surgery exclusively. At the end of follow-up, 6 patients died of their disease including all 4 with postsurgical macroscopic residue.
  
  
  
  GCT with SMT constitutes a very rare entity in children and adolescents. Surgical removal of the tumor is the cornerstone of the treatment and might be sufficient in selected cases. In the remaining cases, the best management is still unknown and should take into account both components and their respective chemosensitivity. Long-term surveillance is advised for patient with unresected teratoma as late transformation can occur.
authors.affiliation: *Institute of Pediatric Hematology and Oncology §Department of Pathology, Women and Children's Hospital, Lyon †Department of Child and Adolescent Cancer, Gustave Roussy Cancer Institute, Villejuif ‡Department of Pediatric Oncology, University Hospital Center of Nantes, Nantes ∥Department of Pediatric Oncology of Timone Children's Hospital, Marseille ¶Department of Pediatric Oncology, University Hospital Center of Rouen, Rouen #Department of Pediatric Oncology, Children's Hospital, Toulouse ††Department of Pediatric, Adolescents, Young Adults, Institut Curie, Paris, France **Department of Pediatric Hematology and Oncology, Lebanese Hospital, University Medical Center, Beirut, Lebanon.
authors.forename: Cecile
authors.initials: C
authors.lastname: Faure Conter
authors.forename: Brice
authors.initials: B
authors.lastname: Fresneau
authors.forename: Estelle
authors.initials: E
authors.lastname: Thebaud
authors.forename: Amandine
authors.initials: A
authors.lastname: Bertrand
authors.forename: Frederique
authors.initials: F
authors.lastname: Dijoud
authors.forename: Angelique
authors.initials: A
authors.lastname: Rome
authors.forename: Cecile
authors.initials: C
authors.lastname: Dumesnil
authors.forename: Marie Pierre
authors.initials: MP
authors.lastname: Castex
authors.forename: Anguella
authors.initials: A
authors.lastname: Ghanem
authors.forename: Daniel
authors.initials: D
authors.lastname: Orbach
mesh_terms: D000293:Adolescent; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005602:France; D006801:Humans; D007223:Infant; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000401:mortality / Q000473:pathology / Q000628:therapy; D012189:Retrospective Studies; D013514:Surgical Procedures, Operative; D015996:Survival Rate; D016896:Treatment Outcome