Reproducibility of technetium-99m-MAG3 clearance using the Bubeck method

Area of Science:

• Nuclear medicine
• Nephrology
• Oncology

Background:

• Renal function monitoring is crucial in cancer patients undergoing chemotherapy.
• 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) scintigraphy is used to assess renal function.
• Estimating the reproducibility of 99mTc-MAG3 clearance is essential for accurate patient management.

Purpose of the Study:

• To estimate the reproducibility of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) clearance calculated using a single-sample method.
• To evaluate the reliability of 99mTc-MAG3 clearance measurements in patients with urological or ear, nose and throat cancer.

Main Methods:

• A retrospective analysis of 147 cancer patients with at least two 99mTc-MAG3 clearance studies was performed.
• Clearance was calculated using the Bubeck method, comparing consecutive measurements.
• Pairs with >5% change in split renal function or >50-day interval were excluded to ensure data reliability.

Main Results:

• 242 pairs of clearance data were analyzed.
• A reproducibility error of 11.7% was calculated for 99mTc-MAG3 clearance.
• No significant deviation in clearance was observed due to chemotherapy, except between specific early investigations.

Conclusions:

• The reproducibility error of 99mTc-MAG3 clearance using the Bubeck method is acceptable (< or =11.7%).
• This level of reproducibility is suitable for monitoring renal function, considering the inherent variability of tubular function.
• The findings support the use of 99mTc-MAG3 clearance for assessing renal function changes during chemotherapy.