title: [Clinicopathologic and prognostic study of pediatric immature teratoma].
abstract: OBJECTIVE
  To study the clinicopathologic features and biologic behavior of pediatric immature teratoma.
  
  
  METHODS
  The clinical data, pathologic features, immunohistochemical findings (for cyclin D1, P27 and Ki-67) and follow-up information of 39 cases of pediatric immature teratoma were analyzed.
  
  
  RESULTS
  Amongst the 39 cases studied, 12 arose in the sacrococcygeal region, 12 in testis, 5 in retroperitoneum, 4 in ovary, 4 in abdomen and 2 in mediastinum. Histologically, 16 cases were of grade 1, 8 cases of grade 2 and 15 cases of grade 3. Seven of the cases contained foci of yolk sac tumor. Immature neuroepithelial features used in histologic grading included the presence of primitive neural tubules, immature rosettes, undifferentiated neuroblastoma cells and primitive neuroectodermal structures. Immunohistochemical study showed that cyclin D1 was positive in 3 cases of grade 1 tumors, 4 cases of grade 2 tumors and 9 cases of grade 3 tumors. The positivity rates for p27 were 8, 3 and 6 cases respectively, while those for Ki-67 were 3, 4 and 13 cases respectively. Follow-up data were available in 30 cases. Three of them, including 2 cases with histologic grade 3 (with or without yolk sac tumor component), recurred after operation.
  
  
  CONCLUSIONS
  The expression of cyclin D1 and Ki-67 is a useful adjunct in histologic grading. On the other hand, p27 overexpression shows little correlation with tumor grade. The prognosis of immature teratoma in children is different from that in adults. Sacrococcygeal immature teratoma occurring in patients younger than 1 year old and with low histologic grade do not require postoperative chemotherapy if the tumor is completely excised. Similarly, for testicular immature teratoma occurring in patients below 1 year of age, regardless of tumor grading, need no adjunctive therapy. On the other hand, ovarian immature teratoma with high histologic grade requires postoperative chemotherapy, regardless of age of the patients. The presence of microscopic foci of yolk sac tumor is a useful predictor of recurrence in pediatric immature teratoma.
authors.affiliation: Department of Pathology, the Children's Hospital of Jiangxi Province, Nanchang 330006, China.
authors.forename: Wen-ping
authors.initials: WP
authors.lastname: Yang
authors.forename: Yin
authors.initials: Y
authors.lastname: Zou
authors.forename: Chuan-sheng
authors.initials: CS
authors.lastname: Huang
authors.forename: Shu-zheng
authors.initials: SZ
authors.lastname: Zhang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xiao
authors.forename: Kang-lin
authors.initials: KL
authors.lastname: Dai
authors.forename: Hua-sheng
authors.initials: HS
authors.lastname: Zhong
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Xiong
mesh_terms: D000293:Adolescent; D019938:Cyclin D1 / Q000378:metabolism; D018240:Endodermal Sinus Tumor / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008479:Mediastinal Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012186:Retroperitoneal Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D012445:Sacrococcygeal Region; D015996:Survival Rate; D013724:Teratoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D013736:Testicular Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D000509:alpha-Fetoproteins / Q000378:metabolism
chemical_list: D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen; D000509:alpha-Fetoproteins; C413374:p27 antigen; D019938:Cyclin D1