Objective: To verify the possibility of detecting N-myc amplification in fine needle aspiration (FNA) cytology from neuroblastomas by the Southern blotting technique.
Study design: Fifteen neuroblastomas diagnosed by FNA in the Department of Pathology, Hospital de S. João, between 1990 and 1998, were studied for N-myc amplification using the Southern blotting technique in cytologic and histologic material.
Results: DNA extraction from the cytologic material was performed in all cases (N = 15). In two cases the quality/quantity of the DNA did not allow the study of N-myc status by the Southern blotting technique. We detected N-myc amplification in 1 of 13 patients (7.6%) from whom material was available for genetic study.
Conclusion: It is possible to use the Southern blotting technique to demonstrate N-myc amplification in material obtained from FNA of neuroblastomas.