[en] Prostate cancer has a high bone metastasis tendency. At the time of initial diagnosis, there is a high rate of bone metastasis. Early detection of bone metastases in patients with prostate cancer has important significance for staging, treatment and prognosis of prostate cancer. Radionuclide bone imaging(SPECT) is a commonly used imaging examination method of bone metastases, which had a higher detection rate in early bone metastases. Combined with X-ray, CT, MRI and other ways can improve the accuracy of bone metastases. This review summarizes the research status of the imaging examination of bone metastasis of prostate cancer, which provides the imaging evidence for early diagnosis of bone metastases. (authors)

[en] Objective: To estimate effective and organ doses to prostate cancer patients result ing from the whole-body ¹⁸F-Choline, ¹¹C-Choline and ⁶⁸Ga-PSMA PET-CT examinations. Methods: A total of 150 prostate cancer patients who underwent PET-CT scanning from May 2017 to June 2018 were retrospectively analyzed. They were divided into three groups, each with 50 patients, according to the type of positron radiopharmaceuticals injected. All patients used the same PET-CT scan protocol. PET component dose was calculated by using OLINDA/EXM (version 1.1) software which was based on the MIRD method. The CTDI values were measured by the standard CT phantoms and computed by ImPACT (version 1.0.4) CT, and ImPACT was used for dose calculation from CT. The tissue weighting factors according to ICRP Report 103 were used for effective dose calculation. Results: The effective dose and organ equivalent dose from ¹⁸F/¹¹C-Choline and ⁶⁸Ga-PSMA PET/CT examinations were estimated. The voltage and current of Topogram scan were 120 kV and 35 mA, respectively, as well as 120 kV and (135.6 ± 9.4) mA for low-dose CT scan. The injected activity of ¹⁸F-Choline, ¹¹C-Choline and ⁶⁸Ga-PSMA was (279.2 ± 13.2), (350.2 ± 39.9) and (186.8 ± 19.4) MBq, respectively. The effective dose was (5.0 ± 0.2), (1.6 ± 0.2) and (3.0 ± 0.3) mSv, respectively (F = 837.0, P < 0.001). The CT effective dose was (11.4 ± 0.2) mSv. The total effective dose for three groups were (16.4 ± 0.3), (13.0 ± 0.3) and (14.4 ± 0.4) mSv, respectively. The mean organ equivalent doses were statistically significantly different among groups (F = 381.2-1637.7, P < 0.001). The highest organ equivalent dose was to kidney for ¹⁸F-Choline and ⁶⁸Ga-PSMA PET/CT scans and thyroid for ¹¹C-Choline PET/CT scan. Conclusions: The effective dose to the prostate cancer patients who underwent PET-CT scanning was from 13.0 to 16.4 mSv, with vast majority of these doses coming from CT scans. The lowest radiation dose to the patients was caused by ¹¹C-Choline PET-CT examination, suggesting that it would be a potential prostate cancer PET radiotracer. (authors)

[en] Objective: To evaluate the clinical curative effect of zoledronic acid combined with ⁸⁹Sr for the treatment of prostate cancer patients with bone metastases. Methods: A total of 74 prostate cancer patients were randomly divided into three groups according to treatment, as follows: Group A (n = 25; median age, 66 years; age range, 46-87 years), zoledronic acid with ⁸⁹Sr; Group B (n = 25; median age, 65 years; age range, 43-89 years), zoledronic acid; and Group C (n = 24; median age, 66 years; age range, 47-85 years), ⁸⁹Sr. Groups B and C were the control groups. All patients were followed up for 6 months, during which the status of bone pain relief and improvement in the number of bone metastatic lesions were observed. Results: The three groups showed similar baseline characteristics. Total pain relief efficiency in group A was 88.0%, while those of the control groups were 72.0%(group B) and 79.2%(group C). Pain palliation of group A significantly differed from those of groups B and C (χ² = 8.959, P < 0.05). Regression of bone metastatic lesions in group A was 88.0%, while those of the control groups were 44.0%(group B) and 75.0%(group C). Significant difference was found between group A and the two control groups (χ² = 9.096, P < 0.05). Conclusion: Combined therapy of zoledronic acid and ⁸⁹Sr in prostate cancer patients with painful bone metastases was more effective in treating pain and improving the quality of life than separate administration of zoledronic acid or ⁸⁹Sr. (authors)

[en] Objective: To estimate the effective and organ dose of patients receiving the ¹⁸F-FDG (¹⁸F-2-deoxy-D-glucose) and ¹⁸F-FET (O-2-¹⁸F-fluoroethyl-L-tyrosine) PET-CT whole body examinations. Methods: Two PET-CT scanning protocols were used for whole body imaging. The effective and organ dose of PET part were calculated using the internal dose computer program IDAC 2.1 based on MIRD method. The effective and organ doses of CT part were calculated by Virtual-Dose software, and the sum of CT and PET dose was the total effective dose of patients. Results: In the conventional PETCT scan protocol, the effective dose was (4.81 ± 1.04) mSv for male and (6.09 ± 0.73) mSv for female patients from ¹⁸FFDG; the effective dose was (2.67 ± 0.38) mSv for male and (3.21 ± 0.38) mSv for female patients from ¹⁸F-FET; the effective dose was (5.63 ± 0.32) mSv for male and (5.51 ± 0.29) mSv for female patients from CT component. The total effective dose was (10.44 ± 1.09) mSv for male and (11.60 ± 0.79) mSv for female from ¹⁸F-FDG PET-CT examination, respectively. Whereas it was (8.30 ± 0.50) mSv for male and (8.72 ± 0.49) mSv for female from ¹⁸F-FET PET-CT examination, respectively. In the diagnostic-quality CT scan protocol, the effective dose was (16.28 ± 1.01) mSv for male and (13.49 ± 0.72) mSv for female patients from CT component. The total effective dose was (21.09 ± 1.45) mSv for male and (19.58 ± 1.03) mSv for female patients from ¹⁸F-FDG, respectively. Whereas it was (18.95 ± 1.08) mSv for male and (16.70 ± 0.81) mSv female patients from ¹⁸F-FET. Conclusion: Different PET-CT scan parameters caused the patient to be exposed to different radiation doses. In the daily work, we should optimize the acquisitive parameters of PET and CT according to the actual situation of the examinee, and reduce the dose of examinee to practice the optimization of radiation protection. (authors)