Chromosome 9 anomalies as the primary clonal alteration in a case of squamous cell carcinoma of the epiglottis.

We present the cytogenetic characterization of a short-term culture of a primary squamous cell carcinoma of the epiglottis from a 67-year-old male patient who was admitted to this hospital for treatment. This patient had a history of chronic exposure to tobacco and alcohol, environmental carcinogens known to be related to the etiology of the disease. The tumor karyotype showed three distinct clones: 1) cells with chromosome 9 anomalies; 2) cells with chromosome 9 and other clonal structural anomalies involving chromosomes 1, 11, 14, and 17; and 3) cells whose chromosomes were partially or totally pulverized. The anomalies on chromosome 9 were homozygous inversion (p12q13), deletions at regions q22, q34.1, and p13, and i(9q) formation. Structural clonal anomalies on other chromosomes included translocations, deletions, and isochromosome formation. The presence of a chromosome 9 anomaly alone or in conjunction with other anomalies suggests that this aberration may be a nonrandom primary event in the progression of squamous cell carcinoma of the head and neck.