New chromosome techniques in the study of human neoplasia.

Amethopterin synchronization of bone marrow and lymph node cells makes it possible to obtain well banded and elongated metaphases and prometaphases in the majority of patients with leukemia and lymphoma. Chromosomal analysis of most neoplasias is also possible through the use of mild tumor cell disaggregation methods, short term culture on feeder layers, and special media that help in the preferential proliferation of cancer cells. In the past, only about half of all patients with acute leukemia and lymphoma could be shown to have a chromosomal defect, and only a small proportion of solid tumors could be analyzed. With the new technology, abnormal tissue from the majority of cancer patients can be successfully studied and chromosomal abnormalities detected.