Seasonal variation in incidence of pediatric medulloblastoma in the United States, 1995-2001.
OBJECTIVE
Brain tumors are the second most common pediatric malignancy. The literature suggests that one of the most common subtypes of malignant childhood brain tumor, medulloblastoma, has some seasonal variation in incidence by month of birth.


METHODS
Data from cases in the Central Brain Tumor Registry of the United States, including primary brain tumor cases diagnosed in children (0-19 years) between the years 1995 and 2001 from 13 state cancer registries, were analyzed to determine whether there was seasonal variation. Analyses were performed using Edwards' test for sinusoidal variation, which uses case frequencies per month, and tests whether frequencies follow a sine function over 12 months.


RESULTS
Seasonal variation in incidence by month of birth was highly statistically significant for medulloblastoma, not otherwise specified (NOS) (p = 0.016), with the peak occurring in October. Medulloblastoma, NOS also demonstrated seasonal variation in incidence by month of birth in children aged 5-19 (p = 0.041), especially females aged 5-19 (p = 0.034), with the peak in October. There were no significant results for brain tumors overall, or for the other most common pediatric tumor subtypes (pilocytic astrocytoma, other astrocytoma, and ependymoma).


CONCLUSIONS
These preliminary results indicate seasonal variation unique to medulloblastoma incidence by month of birth and may provide evidence for an environmental exposure etiology, though further studies are needed to explore specific hypotheses.
Hoffman
Sara
S
Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, IL 60612, USA.
Schellinger
Kate A
KA
Propp
Jennifer M
JM
McCarthy
Bridget J
BJ
Campbell
Richard T
RT
Davis
Faith G
FG
D000293:Adolescent; D000328:Adult; D001723:Birth Rate; D002528:Cerebellar Neoplasms / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008527:Medulloblastoma / Q000453:epidemiology*; D036801:Parturition; D012042:Registries; D012621:Seasons; D014481:United States / Q000453:epidemiology