An automated synthesis of 177Lu-EDTMP as an efficient bone-seeking therapeutic radiopharmaceutical.

OBJECTIVE: Radiolabeled bisphosphonates have found wide clinical use in nuclear medicine for palliative therapy of bone metastases. 177Lu-EDTMP was used to relieve metastatic bone pain in patients with breast or prostate cancer. The therapeutic efficacy of 177Lu-EDTMP at 1-, 3-, 6-, and 8-weeks post-therapy was evaluated using Standard Pain Scoring Assessment Criteria. In addition, toxicity was evaluated in terms of hematological parameters using the Common Terminology Criteria for Adverse Events V4.0. PATIENTS AND METHODS: A fully automated synthesis of 177Lu-EDTMP was achieved in this study with high radiochemical efficiency and high radiochemical purity. During the study, 75 patients (57 M: 18 F, mean age: 68.0 ± 11.1 years) of breast/prostate cancer with documented skeletal metastases were included. Patients were administered intravenously with 177Lu-EDTMP at a dose rate of 22.2-37.0 MBq/kg following a fully automated synthesis of 177Lu-EDTMP using a disposable cassette system. RESULTS: Among the 75 patients all treated with 177Lu-EDTMP, 59 patients were responsive and the remaining 16 patients did not respond to the therapy. Mean pain score values in the responder group were 5.60 ± 0.5, 4.3 ± 0.1, 2.6 ± 0.4 and 1.4 ± 0.7 at weeks 1, 3, 6, and 8, respectively. Also, the mean pain score decreased from a baseline score of 7.6 ± 1.6 to 1.4 ± 0.7 at week 8 in the responder group. Statistical analysis of the pain score data showed a significant decrease in pain score after each radiopharmaceutical treatment, compared to the baseline scores (p <0.0001). Mild to severe toxicity was observed in two patients each treated with 177Lu-EDTMP. CONCLUSIONS: These findings demonstrated that the 177Lu-EDTMP radiopharmaceutical could be used safely to achieve considerable therapeutic efficacy, in metastatic bone pain palliation together with the safe clinical application and low radiation exposure during preparation.

Evaluation of eustachian tube function with ventilation scintigraphy by using 133Xe gas.

The aim of this study was to evaluate Eustachian tube function by ventilation scintigraphy. In 13 patients with normal tube function and 16 with one-sided tube dysfunction, 50 MBq 133Xe was applied into the nasopharyngeal space through a tube inserted into the nasal cavity. Immediately after the insufflation, the patients were asked to perform three Valsalva manoeuvres. The visualization of the middle ear was possible in 10 of the 13 patients (77 per cent) with normal tube function. Decreased uptake of the middle-ear region in the side of dysfunction was demonstrated in 11 of the 16 patients (68.7 per cent) with one-sided tube dysfunction. Quantitative evaluation by region of interest technique revealed that by using percentage retention of activity and uptake rates, there were significant differences between the sides of dysfunction and sides of normal tube function (p < 0.05) and also between sides of dysfunction and both sides of controls (p < 0.05). There was no significant differences between normal sides of patients and both sides of controls (p > 0.05). As a conclusion, this method is non-invasive, easy- to perform and has a low radiation burden in the evaluation of Eustachian tube function. Although the number of patients is limited, the test seems to be applicable with a success rate of about 74 per cent.