Residual chromosomal aberrations in female cancer patients after irradiation therapy

Therapeutic irradiation produced chromosomal aberrations in peripheral circulating lymphocytes which were assessed by analysis of cells from serial, spaced peripheral blood cultures obtained during and after therapy. The initial and most immediate effeets were quantitative, and affected the frequency of cells with chromosome complements deviating from the normal complement of 46. This increase in the number of ancuploid cells rises to a plateau during therapy, and by one year after the conclusion of therapy the number of cells with 46 chromosomes began a slow rise to pretreatment levels. Although the chromosomal complement may have reached the preirradiation modality, persisting structural aberrations of the chromosomes were seen long after radiation therapy.