Single-photon emission CT using 99mTc-dimercaptosuccinic acid (DMSA) for characterization of suspected renal masses

Objective: A retrospective analysis of the clinical utility of Tc-99m-dimercaptosuccinic acid (DMSA) single photon emission CT (SPECT) for characterization of suspected renal masses. Methods: 15 patients who had undergone Tc-99m-DMSA SPECT were identified, and 13 patients also had SPECT/CT. Tc-99m-DMSA uptake in the renal lesion was characterized semiquantitatively. Other imaging tests, histology and clinical data were available for correlation. Results: Tc-99m-DMSA was not taken up in all five renal masses with histological confirmation of malignancy (uptake 7-19% of normal renal tissue); in two further masses, which were clinically likely to be malignant; and in one indeterminate mass (lack of sufficiently long follow-up). No renal malignancy was identified in any of the seven patients whose renal masses had normal Tc-99m-DMSA uptake (41-130%). Conclusion: Although caution with regard to applying those results in clinical practice must be advised, owing to the retrospective nature of this report and the small number of patients included, it seems that Tc-99m-DMSA SPECT shows a clinically useful diagnostic accuracy for distinguishing true renal masses (which in many cases require surgery) from pseudomasses. Advances in knowledge: Tc-99m-DMSA SPECT is a clinically useful adjunct test for characterization of suspected renal masses.