Objective:

To investigate the radiation levels around patients with gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN) at different times after treatment with

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Lu-DOTATATE

and to provide a reference for radiation safety and patient management.

Methods:

GEP-NEN patients who were hospital

ized for

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Lu-DOTATATE in Fudan University Shanghai Cancer Center from May to November 2023 were selected as the research subjects. These patients were treated with a single intravenous dose of (7 618.5±241.9) MBq of

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Lu-DOTATATE. At different time points after administration

the peripheral dose equivalent rate at 1 m in front of the patient was measured

and the change pattern of the peripheral dose equivalent rate over time was analyzed.

Results:

A total of 78

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Lu-DOTATATE treatments were performed in 30 GEP-NEN patients. Immediately after the end of administration

the average dose equivalent rate at 1 m in front of the patient was 20.0 μSv/h. The peripheral dose equivalent rate decayed exponentially with time

and the average time it dropped to 10 μSv/h was 3.95 h

and the upper limit of the 95% CI was 4.6 h. The effective half- life of the peripheral dose equivalent rate within 24 h was 1.42 h.

Conclusion:

After each

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Lu-DOTATATE treatment

the ambient dose equivalent rate decreased rapidly over time

and the ambient dose equivalent rate at 1 m dropped to 10 μSv/h at an average of 3.95 h. At 4.6 h

95% of the patients could drop below 10 μSv/h. This study provides experimental data and basis for the formulation of discharge criteria or patient management for patients treated with

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Lu-DOTATATE in China.