Pediatric nasopharyngeal carcinoma: better prognosis and increased c-Kit expression as compared to adults.
BACKGROUND
Nasopharyngeal carcinoma (NPC) in children is distinguishable from the adult form by its close association with Epstein-Barr virus (EBV) infection, a higher rate of undifferentiated histology, and a greater incidence of advanced locoregional disease.


METHODS
Sixteen NPC patients, < or =20 years of age were identified from our 1976-2001 tumor registry records. Clinical stage, treatment, recurrence, and survival were evaluated. Sections were stained by immunohistochemistry for p53, Bcl-2, Ki67, and c-Kit and by in situ hybridization for EBER. Obtained data were compared to 32 adult patients. All patients had undifferentiated or non-keratinizing NPC.


RESULTS
EBER was positive in 100% of children, compared to 90% of adults. Comparing children to adults, median Ki67 index was 49% and 30%, p53 positive tumors were 69% and 94%, positive Bcl-2 was 63% and 72%, and positive c-Kit was 88% and 28%, respectively.


CONCLUSIONS
No parameter had significant predictive values for survival, although c-Kit expression had a trend for better prognosis in the pediatric group. By univariate analysis of all 48 cases, positive c-Kit was associated with better survival (P = 0.029), largely due to the better survival of the pediatric group. By multivariate analysis, increased stage (P = 0.006) and older age (P = 0.044) correlated with worse prognosis.
Bar-Sela
Gil
G
Department of Oncology, Rambam Medical Center and Technion-Israel Institute of Technology, Haifa 31096, Israel. g_barsela@rambam.health.gov.il
Ben Arush
Myriam Weyl
MW
Sabo
Edmond
E
Kuten
Abraham
A
Minkov
Ira
I
Ben-Izhak
Ofer
O
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002648:Child; D005260:Female; D006801:Humans; D007557:Israel / Q000453:epidemiology; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000401:mortality; D011379:Prognosis; D016016:Proportional Hazards Models; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D015996:Survival Rate; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D019009:Proto-Oncogene Proteins c-kit