Frequent chromosomal gains in recurrent juvenile nasopharyngeal angiofibroma

Juvenile nasopharyngeal angiofibroma (JNA) is a rare benign tumor, mostly affecting adolescent males. Some patients develop recurrences after surgery independently of completeness of removal. Only very limited data concerning underlying chromosomal changes are available. We therefore analyzed samples of 22 JNAs, including six recurrences, with comparative genomic hybridization (CGH). Additionally, quantitative image cytometry was used for measurement of DNA aneuploidy in representative samples. Of the 13 primary JNAs without later recurrence, DNA gains were identified on autosomes in only two samples. Four patients with one or two recurrences were included in the study; for one of these, no material of the primary tumor was available for analysis. Looking at autosomes, two of the three available primaries displayed multiple gains; in one of those, two additional losses were observed. Multiple gains were detected in two of the four first recurrences, but none in the two second recurrences. Across all 22 samples, gains occurred in more than one sample on chromosomes arms 1p, 9q, 10q, 12q, 16p, 16q, 17q, 19p, 19q, 20q, and 22q. Losses were found in a single case exclusively on chromosome 4. Sex chromosomes were frequently affected in both primary tumors and recurrences. There was no correlation among tumor staging, age, and DNA amplification. No DNA aneuploidy was detected, a finding in accordance with the generally benign characteristics of JNAs. Our observations suggest that in JNA the activation of oncogenes is more likely than the inactivation of tumor suppressor genes. Autosomal gains in the primary tumor should be further evaluated as markers for a potentially increased risk of recurrence after surgical removal in this entity.