Loco-regional extensions of central nervous system germ cell tumors: a retrospective radiological analysis of 100 patients.

PURPOSE: The current staging system of central nervous system (CNS) germ cell tumors (GCT) includes a binary classification in "localized" or "metastatic" disease based on the absence or presence of leptomeningeal dissemination. Loco-regional tumor dissemination has been barely described whereas its accurate definition might be useful in terms of prognosis and treatment, especially for radiation therapy planning. Our purpose was therefore to describe MR patterns and prevalence of loco-regional extensions of these tumors. METHODS: One hundred consecutive patients (median age 16.3 years, range 7-41 years, sex ratio 7:1) with a histologically or biologically proven CNS GCT were retrospectively included. Brain and spinal MRI at diagnosis were reviewed by two neuroradiologists focusing on MR patterns of primaries and loco-regional extensions. When available, follow-up MR exams were analyzed. RESULTS: Pure germinoma represented 84/100 cases. Primaries were unifocal pineal (n = 49/100), bifocal pineal and supra-sellar (n = 27/100), isolated supra-sellar (n = 21/100), isolated basal ganglia (n = 2/100) or trifocal pineal, supra-sellar, and basal ganglia (n = 1/100). Metastatic disease occurred in 6/100 patients (depicted by MRI in two and CSF cytology in four). Loco-regional extensions were observed in all patients and classified as follows: third ventricle (n = 88/100), thalamus (n = 47/100), midbrain (n = 42/100), distant sub-ependymal areas (n = 19/100), optic pathways (n = 19/100), lateral ventricles (n = 7/100), cavernous sinus (n = 6/100), corpus callosum (n = 4/100), and fourth ventricle (n = 3/100). CONCLUSION: CNS GCT present with specific loco-regional extensions at diagnosis. Improving their recognition will be helpful to further understand their prognostic value and potentially to optimize the treatment.

Bone Scintigraphy After a Negative Radiological Skeletal Survey Improves the Detection Rate of Inflicted Skeletal Injury in Children.

Background: Timely diagnosis of child physical abuse is of paramount importance. The added value of bone scintigraphy (BS) after a negative radiological skeletal survey (RSS) in children with suspected physical abuse has never been evaluated. Objective: The objective of this study was to assess the extent to which BS could improve the detection rate of skeletal injury in children with suspected physical abuse with an initial negative RSS. Methods: We used discharge codes to retrospectively identify children evaluated for suspected physical abuse in a university hospital (Nantes, France). We included all consecutive children younger than 3 years old who underwent both RSS and BS, with an interval of ≤96 h between tests, from 2013 to 2019. BS and RSS results were interpreted independently during the study period. We specifically analyzed BS results for children with a negative RSS to assess the value of BS as an add-on test. Results: Among the 268 children ≤3 years old with suspected physical abuse who underwent RSS, 140 (52%) also underwent BS within 96 h and were included in the analysis. The median age was 6 months old (interquartile range: 3-8). The detection rate of ≥1 skeletal injury with RSS alone was 49% (n = 69/140, 95% CI: 41-58%) vs. 58% (n = 81/140, 50-66%) with RSS followed by add-on BS, for an absolute increase in the detection rate of 9% points (95% CI: 4-14%). The number of children with a negative RSS who would need to undergo BS to detect one additional child with ≥1 skeletal injury was 6 (95% CI: 4-11). Conclusion: In young children with suspected physical abuse with a negative RSS, add-on BS would allow for a clinically significant improvement in the detection rate of skeletal injuries for a limited number of BS procedures required. Prospective multicenter studies are needed to confirm these findings.