Relationship between cytogenetic aberrations by CGH coupled with tissue microdissection and DNA ploidy by laser scanning cytometry in head and neck squamous cell carcinoma

Background: The relationship between DNA sequence copy number aberrations ( DSCNAs) and DNA ploidy in head and neck squamous cell carcinomas (HNSCCs) i s still controversial. Materials and Methods: We analyzed DSCNAs by com parative genomic hybridiza tion (CGH) combined with microdissection and DNA ploidy by laser scanning c ytometry (LSC) in 18 surgically removed HNSCCs and compared the data. Results: Copy number increases were most frequently observed on chromosomes 3q (16 cases), 8q (13 cases) and 12p (11 cases). Copy number decreases wer e observed on chromosome Sp (14 cases). LSC revealed DNA aneuploidy in 10 o f the 18 cases. All DNA aneuploid tumors exhibited gain or amplification of DNA copy num ber at 12p11-12.1, whereas gain of DNA copy number was found in only 1 of 8 diploid tumors. DSCNAs were more frequent in DNA aneuploid t umors than in diploid tumors (P < 0.005). Conclusions: The present observations indicate a close relationship between DSCNAs and DNA ploidy in HNSCCs. Cytometry 40:161-166, 2000. (C) 2000 Wile y-Liss, Inc.