Specificity of 6q- markers and other recurrent deviations in human malignant salivary gland tumors.

The chromosomal banding patterns in 20 human malignant salivary gland tumors are reported. Abnormal stem-and/or sidelines were observed in 14 cases, and abnormal clones and variant cells in the remaining 6 cases. No less than 8 tumors showed clonal rearrangements involving the long arm of chromosome 6, i.e. terminal deletions with breakpoints in the 6q22-25 region. The possible involvement of c-myb or a putative tumor suppressor gene in the 6q deletions is considered. Other recurrent deviations were loss of the Y chromosome, trisomy 8 and 11q- markers. The combined data from this and previous studies show that most of the rearrangements are not restricted to a certain type of malignant salivary gland tumor, but are seen in several tumor types, indicating a close evolutionary relationship between different malignant salivary gland tumors.