Relevance of external beam dose-response relationships to kidney toxicity associated with radionuclide therapy.
The importance of the kidney as a dose-limiting organ is likely to increase as smaller molecular vectors and radiometals become more commonly used in targeted radionuclide therapy. Data derived from kidney irradiation by external-beam therapy (XRT) indicate that the kidney is radiosensitive. The features of radiation nephropathy seen post-treatment appear similar between local XRT, total-body irradiation (TBI), and radionuclide therapy. For uniform kidney irradiation, tolerance doses appear to be approximately 15-17 Gy in 2 Gy fractions for local XRT and probably less than this (approximately 12 Gy in 2 Gy fractions) when radiation is delivered systemically as TBI in the context of bone marrow transplant protocols. Animal studies indicate that the linear quadratic (LQ) model with an alpha/beta parameter of 1.5-3 Gy seems to adequately describe the XRT fractionation sensitivity of kidney for doses per fraction down to approximately 1 Gy, but may underestimate the effectiveness of fraction sizes less than this. Animal studies have also clarified the dose-dependency of the time to expression of radiation nephropathy and have indicated that radiation nephropathy may be alleviated by pharmacological means.
Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA. odonoghj@mskcc.org
Joseph
J
O'Donoghue
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D007674:Kidney Diseases / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D011836:Radiation Tolerance; D011868:Radioisotopes / Q000009:adverse effects* / Q000627:therapeutic use* / Q000633:toxicity; D013997:Time Factors
D011868:Radioisotopes