Incidence of atypical teratoid/rhabdoid tumors in children

Abstract

on behalf of the Austrian Brain Tumor Registry BACKGROUND: Atypical teratoid/rhabdoid tumors are highly malignant embryonal central nervous system (CNS) tumors that were defined as an entity in 1996. As compared with other malignant CNS tumors, their biological behavior is particularly aggressive, but patients may benefit from an intensified treatment. Atypical teratoid/rhabdoid tumors display a complex histomorphology, which renders them prone to misdiagnosis. They occur predominantly in young children, with an estimated prevalence of 1% to 2% among all pediatric CNS tumors. However, populationbased data on the incidence of these tumors are not yet available. METHODS: A nation-wide survey of malignant high-grade CNS tumors (World Health Organization grade III/IV), diagnosed in children (aged birth to 14 years) from 1996 to 2006 was conducted by the Austrian Brain Tumor Registry. A central histopathology review was performed including the assessment of SMARCB1 (INI1) protein status. RESULTS: A total of 311 newly diagnosed, malignant CNS tumors were included. Atypical teratoid/rhabdoid tumors constituted the sixth most common entity (6.1%), referring to an age-standardized incidence rate of 1.38 per 1,000,000 person-years in children. Peak incidence was found in the birth to 2 years age group, where they were as common as CNS primitive neuroectodermal tumors and medulloblastomas. A total of 47.4% of atypical teratoid/rhabdoid tumors were initially diagnosed, whereas 52.6% were retrospectively detected by the central review. The 5-year survival of atypical teratoid/rhabdoid tumor patients was 39.5%, with 66.7% in the correctly diagnosed group versus 15.0% in the not recognized group (P ¼ .0469). CONCLUSIONS: Clinicians and pathologists should be aware of the high incidence of atypical teratoid/rhabdoid tumors in young children to optimize diagnostic and therapeutic management of patients with these tumors. Cancer 2010;116:5725-32. V C 2010 American Cancer Society.KEYWORDS: atypical teratoid/rhabdoid tumor, central nervous system neoplasm, childhood, epidemiology, population-based incidence, survival.Central nervous system (CNS) tumors represent >20% of all childhood malignancies (0-14 years) in developed countries 1,2 and constitute the most common cause of cancer-related death in this age group.

Childhood Brain Tumor Epidemiology: A Brain Tumor Epidemiology Consortium Review

“…Average annual age-adjusted incidence rates range from 0.07–0.14/100,000 persons. (14, 15) Prognosis is generally poor, though survival increases with age. (14–18) Overall, median survival is usually between 6–18 months.…”

“…(14, 15) Prognosis is generally poor, though survival increases with age. (14–18) Overall, median survival is usually between 6–18 months. (16, 19–21) Most analyses show that ATRTs are more common in males (15, 16, 22) and among whites.…”

“…(15, 23) A a systematic diagnostic approach for ATRT was not common until 2005; prior to that these tumors were frequently misclassified, mostly as MBs or PNET. (14)…”

Atypical Teratoid/Rhabdoid Tumor of the Spinal Cord in a Child: Case Report and Comprehensive Review of the Literature

“…Peak incidence of AT/RT is among children younger than 3 years of age [2, 3]. This tumor typically arises from the cerebellum and the cerebral hemispheres, with a very low incidence in the spinal cord [1, 3].…”

NKG2D ligand expression in pediatric brain tumors

“…High-grade pediatric tumors also include rarer or divergent diagnoses, such as primitive neuroectodermal tumor (PNET, WHO grade IV) and atypical teratoid/rhaboid tumor (AT/RT, WHO grade IV), accounting for <5% and 1% of all pediatric CNS tumors, respectively. 4,5 Despite the aggressive nature of high-grade pediatric brain tumors, many of these cancer types respond well to treatment. 6 Following standard of care therapy of tumor resection, chemotherapy, and radiation therapy, 70-80% of children diagnosed with average-risk medulloblastoma are disease-free 5 y after initial diagnosis.…”