American Society for Clinical Pathology (ASCP) Technologist in Cytogenetics certification (ASCP CG) Practice Test

In which situation can a blood sample be used for cytogenetic studies of a malignancy?

1. Only when examining normal cells

2. When dividing leukemic cells are present in circulation

3. When sample is fresh and not cultured

4. Upon initiation of treatment

The correct answer is: When dividing leukemic cells are present in circulation

In cytogenetic studies of a malignancy, blood samples are most valuable when they contain dividing leukemic cells present in circulation. The presence of these actively dividing cells allows for the successful analysis of chromosomal abnormalities commonly associated with malignant conditions, such as various types of leukemia. The analysis is critical in identifying specific mutations or chromosomal translocations that can inform diagnosis, prognosis, and treatment strategies. This scenario is essential because non-dividing cells do not provide the necessary metaphase spreads needed for a thorough cytogenetic assessment. Other scenarios, such as examining only normal cells, would not yield the relevant information regarding malignancies; using samples that are fresh and not cultured might not provide enough cellular material if there are no dividing cells to analyze; and initiating treatment might alter the population of leukemic cells, potentially leading to a sample that is less representative of the disease state at diagnosis. Therefore, the presence of dividing leukemic cells is a critical factor in utilizing blood samples for cytogenetic studies of malignancies.