CHROMOSOME-ABERRATIONS INDUCED IN HUMAN-LYMPHOCYTES AFTER PARTIAL-BODY IRRADIATION

Chromosomal aberrations in peripheral blood lymphocytes obtained from two patients before and after they received one fraction of partial-bo dy irradiation for palliative treatment were analyzed. Blood samples w ere taken 30 min and 24 h after radiation treatment. The yield of dice ntrics obtained from case A 30 min after a partial-body (about 21%) tr eatment with 8 Gy was 0.066/cell, while the yield obtained 24 h after radiation treatment was 0.071/cell. The fraction of irradiated lymphoc ytes that reached metaphase at 52 h was 0.08 as evaluated by mixing cu ltures of in vitro irradiated and unirradiated blood. The yield of dic entrics for blood from case B 30 min after 6 Gy partial-body (about 24 %) irradiation was 0.655/cell, while the yield 24 h after irradiation was 0.605/cell. The fraction of irradiated cells was 0.29. Estimation of doses and irradiated fractions for the two cases using the method p roposed by Dolphin and the Qdr method is discussed. Although there was no significant difference between the mean yields of dicentrics per c ell obtained 30 min and 24 h after radiation treatment, the data obtai ned at 24 h seemed more useful for the purpose of dose estimation. Whe n a higher dose (8 Gy) was delivered to a smaller percentage of the bo dy, underestimation of the dose was encountered. (C) 1995 by Radiation Research Society