Re-HEDP : pharmacokinetic characterization, clinical and dosimetric evaluation in osseous metastatic patients with two levels of radiopharmaceutical dose
1 Cátedra de Radioquímica, Facultad de Química, Uruguay
2 Centro de Medicina Nuclear, Hospital de Clínicas, Facultad de Medicina, Uruguay
3 Centro de Investigaciones Nucleares, Facultad de Ciencias, Uruguay
4 Laboratorio de Oncologia Básica y Biología Molecular, Facultad de Medicina Universidad de la República, Montevideo, Uruguay
5 Oak Ridge National Laboratory, Nuclear Medicine Group, USA
BMC Nuclear Medicine 2001, 1:2 doi:10.1186/1471-2385-1-2Published: 21 November 2001
A study for pain relief therapy with 188Re-HEDP was done in patients with bone metastases secondary to breast and prostate cancer.
Materials and Methods
Patients received 1.3 or 2.2 GBq, in single or multiple doses. Platelets, white and red cells were evaluated during 11 weeks. Pharmacokinetic characterization was done from blood and urine samples for 5 patients along 24 hours. Urinary excretion was evaluated in other 16 patients during 6 hours. Bone uptake was estimated as remaining activity in whole body. Scintigraphic images were acquired at 2 and 24 hs post-administration. Absorbed dose in bone marrow was estimated with Mirdose3. Analgesics intake and pain score were daily recorded. Tumour markers (PSA, and Tn-structure) were monitored in 9 patients during 4 to 6 months. Single doses of low activity (1.3 GBq) were given to twelve patients. Nine patients received multiple doses.
All except one patient had normal levels of platelets, white and red cells. Remaining dose in blood at 2 hours was 9%. Urinary elimination was 58%. Bone uptake at 24 hours was 43% (mean value; n = 5). No changes of the haematological parameters were detected along follow-up period. Pain relief was evidenced by decrease or supression of opioid analgesic and by subjective index. PSA showed a decrease in prostate cancer patients (n = 4). Tn-structure showed a significant increase after 4 to 8 months.
Single or multiple dose scheme could be safely used, with administered activity of 188Re-HEDP up to 60 mCi, with low bone marrow absorbed doses.