NONRANDOM CHROMOSOME-ABERRATIONS AND CLONAL POPULATIONS IN HEAD AND NECK-CANCER

Losses of 3p13-p24, 5q12-q23, 8p22-p23, 9p21-p24, 10p13-pter, 18q22-q2 3, and 21q11.2-q21 (40-60% of tumors), loss of the inactive X and loss (or rearrangement) of Y in 70% of tumors from female and male patient s respectively; and gains of 2 to 5 extra copies of 3q21-qter, 5p14-pt er, 7p13-p22, 8q13-q24.3, and 11q13-q23, (30-40% of tumors) are the mo st common chromosome abnormalities in head and neck squamous cell carc inomas (SCCs). SCCs are monoclonal and cell lines derived from separat e surgeries in the same patient contain closely related subclones. Ana lysis of subclones within tumors provides clues to the sequence of kar yotypic changes. Chromosome hotspots such as loss of distal 18q and ga ins affecting 11q13-11q21 are likely to contain genes important in the development and progression of sec.