Cytogenetic abnormalities in patients with cutaneous T-cell lymphomas.

Cytogenetic studies were conducted in 36 patients with histologically confirmed cutaneous T-cell lymphomas at the National Cancer Institute-Veterans' Administration Medical Oncology Branch. Aneuploidy was observed in 17 (85%) of the 20 lymph nodes, 23 of the 36 peripheral bloods, and five of the 31 bone marros. Aneuploidy was frequently present even when tumor cells were not noted histologically. These findings indicate that cytogenetic studies can be very useful for the early detection of malignant cells even when only a few such neoplastic cells are encountered. In this study, the cytogenetic abnormalities found to be characteristic of the disease included extensive aneuploidy, with both numerical and structural aberrations, a wide range of heteroploidy, and a lack of clone formation until the terminal phase of the disease. The numerical changes most frequently involved chromosomes 8, 15, 11, 17, 21, and 10, and the chromosome most involved in structural aberrations was chromosome 1, followed by chromosomes 7, 14, 16, 6, and 9. Cytogenetic studies demonstrate that neoplasia in the cutaneous T-cell lymphomas commonly involves areas beyond the skin.