TABLE 2

Radiation Dose of 90Y-Ibritumomab (mGy/MBq) Before Rituximab Treatment and Dosimetric Impact of Rituximab Treatment

Radiation dose before rituximab treatment (n = 17)Difference in radiation dose before and after rituximab treatment (n = 16)Statistical significance of comparison (significant if P < 0.05)
TissueMedianRangeMedianRange
Total body0.480.24−0.860.007−0.100−0.065No (P = 0.68)
Liver3.662.11−11.62−0.14−1.24−2.55No (P = 0.27)
Spleen*6.141.82−17.76
Spleen (residence time)3.86 h1.59−10.47 h−0.92 h−7.96−0.08 hYes, decrease (P = 0.0005)
Kidneys3.311.95−4.65−0.31−1.21−1.08No (P = 0.10)
Heart wall2.431.27−3.730.38−0.37−3.24Yes, increase (P = 0.002)
Lungs1.100.41−2.31−0.17−1.22−0.70No (P = 0.24)
Red marrow0.790.32−1.220.046 (n = 15)−0.300−0.430No (P = 0.37)
Tumor*18.1 (n = 28)4.7−98.9
Tumor (residence time)0.87 h0.08−17.9 h−0.24 h (n = 27)−4.93−0.10 hYes, decrease (P = 0.005)
  • * Percentage decrease in dosimetry estimates for spleen and tumor would be identical to percentage decrease in residence time if there were no volume changes after rituximab treatment. However, volume changes were noticed.