Speaker
Dr
Valentina Dini
(Departement of Technology and Health, Istituto Superiore di Sanita', Rome, Italy; INFN, Sez. Roma1- Gruppo Collegato Sanità, Rome, Italy)
Description
The therapeutic application of I-131 is a widespread clinical practice for the treatment of thyroid cancer and hyperthyroidism. Although it has almost no side effects in adults, it is desirable to optimize the applied dose to each patient to maximize the clinical result with acceptable damage to healthy tissues. A previous study showed the occurrence of an adaptive response (AR) in peripheral blood lymphocytes (PBL) in a considerable fraction of patients who received this treatment, although a large inter-individual difference was observed. The aim of the present study was to assess the existence of an AR, in terms of DNA and chromosome damage, in PBL of patients undergoing I-131 therapy in view of developing personalized treatments.
The study considered 18 patients (together with 10 healthy donors matched for age and gender) treated with I-131 for hyperthyroidism at the Dept. of Nuclear Medicine of Policlinico Gemelli (Rome). A combination of in vivo and ex-vivo approaches was used as follows: a) extraction of lymphocytes from patients immediately before and 1 week after I-131 administration; b) in vitro irradiation of these cells with acute doses of gamma rays (challenging doses) c) measurement of radiation-induced damage in terms of H2AX histone phosphorylation and of micronuclei (MN) induction (indicative of DNA and chromosome damage, respectively), d) evaluation, for each patient, of the occurrence of AR or sensitization by comparing the effect of the challenging dose on the samples taken before and 1 week after I-131 administration. The results obtained have shown:
- a large inter-individual variability of PBL response to the challenging dose both in terms of -H2AX assay and MN induction, in contrast to more uniform responses in healthy donors;
- no significant dependence of this response on age or gender;
- an AR after treatment in 36% of patients, and a sensitization in 29% as evaluated by -H2AX assay, and in 39% and 22%, respectively, in terms of MN induction.
- a scarce correlation between the responses in terms of DNA and chromosome damage, likely related to a large individual variability of repair capability in these patients.
These findings indicate that besides the proposed “protective effect” of the radio-metabolic therapy there could be a sensitization effect, and support the need of properly assessing the individual patient’s response in developing any individually tailored treatment.
Primary author
Dr
Valentina Dini
(Departement of Technology and Health, Istituto Superiore di Sanita', Rome, Italy; INFN, Sez. Roma1- Gruppo Collegato Sanità, Rome, Italy)
Co-authors
Dr
Alessandro Giordano
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Donatella D'Ambra
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Ilaria Pecchia
(Departement of Technology and Health, Istituto Superiore di Sanita', Rome, Italy)
Dr
Luisa Lo Conte
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Mariaelena Lago
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Massimo Salvatori
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Mauro Belli
(Departement of Technology and Health, Istituto Superiore di Sanita', Rome, Italy; INFN, Sez. Roma1- Gruppo Collegato Sanità, Rome, Italy)
Dr
Nosdeo Alessandra
(Departement of Nuclear Medecine, Hospital A. Gemelli, Rome, Italy)
Dr
Simone Giustina
(Departement of Technology and Health, Istituto Superiore di Sanita', Rome, Italy; INFN, Sez. Roma1- Gruppo Collegato Sanità, Rome, Italy)
