ALLELOTYPE OF HEAD AND NECK SQUAMOUS-CELL CARCINOMA

To gain a better understanding of the molecular changes in head and ne ck squamous cell carcinoma, we tested every autosomal arm of 29 primar y head and neck tumors for allelic loss. Fifty-eight microsatellite ma rkers were used with at least two-thirds of patients informative for e ach chromosomal arm tested. A high frequency of allelic loss was found on chromosome 9p where 21 of 29 (72%) tumors had loss of heterozygosi ty for at least one polymorphic marker on this arm. Chromosomes 3, 11q , 13q, and 17p exhibited loss in over 50% of all informative cases, wh ile chromosomes 4, 6p, 8, 14q, and 19q displayed loss in greater than 35% of all cases tested. Additionally, several other chromosomal arms exhibited loss of heterozygosity in 20 to 30% of tumors tested. This h igh frequency of allelic loss in these advanced stage neoplasms sugges ts multiple genetic steps in the progression of head and neck cancer a nd identifies several putative tumor suppressor loci on affected chrom osomes.