Cytogenetic study of cancer cells in effusions.

A cytogenetic study of 71 malignant effusions caused by different histopathologic types of cancer was performed by a direct technique. Abnormal metaphases were present in 50 effusions (70.4%); a detailed analysis of banded karyotypes was possible in 20 of these. Trisomies and monosomies were present in 18 of 20 cases. The most common trisomies were +19, +3, +5, +8, +9, +10, +16 and +22; the most frequent monosomies were -X, -2, -5, -7, and -21. Clonal structural abnormalities were identified in 18 of 20 cases. In most instances, they were extensive, and some chromosomes were involved in a nonrandom fashion. Chromosomes #1, #13, and #6 were the most frequently involved in these rearrangements. A common marker chromosome, t(7;9)(p11;q12), was observed in two patients with cancer of the endometrium. Double minutes (DMs) were present in two patients, and there was a homogeneously stained region (HSR) in one.