Doubling Recruitment of Pediatric Low-grade Glioma within Two Decades does not change Outcome – Report from the German LGG Studies

Abstract

Background Successive multicenter studies for pediatric low-grade glioma (LGG) in Germany were accompanied by a doubling of annual recruitment over 2 decades. We investigated whether this increase conveyed a change of epidemiologic characteristics or survival. Methods and results Participating centers reported 4634 patients with the radiologic/histologic diagnosis of LGG (1996–2018), rising from 109 to 278/year. Relating these numbers to all pediatric CNS tumors registered at the German Childhood Cancer Registry, the LGG fraction and annual crude incidence rates increased (32% to 51%; 0.94 to 2.12/100,000 children/adolescents<15 years). The consecutive LGG studies recruited 899 (HIT-LGG 1996), 1592 (SIOP-LGG 2004), and 1836 (LGG-registry) patients with similar distribution of tumor-sites, histology, and dissemination. 5-year overall survival was 96%-98% at median observation time of 8.1 years. Acknowledging unequal follow-up periods, 589/899 (66%), 1089/1582 (69%), and 1387/1836 (76%) patients remained under observation, while 1252/4317 received adjuvant treatment with decreasing frequency of front-line radiotherapy from 16% to 5%. Conclusion Pediatric LGG incidence rates in Germany are now comparable to other European countries. The rise in patient numbers followed implementation of standard-of-care treatment protocols, but did not result in relevant changes of epidemiologic or clinical parameters or survival. Shifts in patient distribution between treatment arms reflect growing acceptance of the LGG therapy algorithm.

Neurosurgical morbidity in pediatric supratentorial midline low‐grade glioma: Results from the German LGG studies

“…The German low‐grade glioma studies offered a nationwide frame for patient care in our noncentralized healthcare system 2 . Participation was encouraged for all pediatric oncological units, yet our data indicate a higher rate of postoperative complications for neurosurgical departments performing less than median reported (3 or less) tumor resections and/or less than median reported (4 or less) tumor‐related procedures during the observation period.…”

“…[1][2][3] They are a heterogeneous biologic group characterized by slow growth, in which molecular diagnostics identified an increasing number of distinctive mutations. [4][5][6] Pediatric LGG (pLGG) are associated with excellent long-term survival, 2,7 but with an often significant morbidity, as well. Over the past decades management of pLGG patients has changed toward integrating surgical and nonsurgical therapies in comprehensive treatment algorithms with the aim of disease control by minimizing long-term toxicity.…”

“…1 Low-grade gliomas (LGG) account for up to half of all pediatric CNS tumors. [1][2][3] They are a heterogeneous biologic group characterized by slow growth, in which molecular diagnostics identified an increasing number of distinctive mutations. [4][5][6] Pediatric LGG (pLGG) are associated with excellent long-term survival, 2,7 but with an often significant morbidity, as well.…”

“…9,[26][27][28][29][30] Therefore, we analyzed data from patients treated within the comprehensive therapy algorithm of the successive German pediatric LGG multicenter studies for the frequency of neurosurgical morbidity. 2,13,14 We investigated the association to patient and tumor characteristics as well as to basic surgical data to identify risk factors.…”

Temporal patterns of childhood cancer survival 1991 to 2016: A nationwide register‐study based on data from the German Childhood Cancer Registry

“…26,65 As it did in Germany, the registration of CNS tumours in other European countries may have improved unevenly over time, which is likely to have influenced both incidence and survivalespecially for nonmalignant CNS tumours. 67 Thus, survival estimates should be compared with caution.…”