Imaging of soft tissue tumors with Tc(V)-99m dimercaptosuccinic acid. A new tumor-seeking agent.

Tumor scintigraphy, using Tc(V)-99m dimercaptosuccinic acid (Tc(V)-DMS) was performed in 58 patients with soft tissue tumors, and the results were compared with that of Ga-67 citrate. Tc(V)-DMS was found to have a sensitivity of 90% for malignant tumors including aggressive fibromatosis compared to that of Ga-67 citrate, which was 56%. However, the specificity of Tc(V)-DMS for these tumors was 71% but with Ga-67 citrate the specificity was 80%. The imaging accuracy in soft tissue tumors with Tc(V)-DMS and Ga-67 citrate was 78% and 71%, respectively. Although the accumulation of Tc(V)-DMS has been detected in some benign soft tissue tumors, the reduced accumulation in inflammatory lesions compared to Ga-67 citrate was recognized, and Tc(V)-DMS could be of great use in the detection of extension or location of malignant soft tissue tumors.