Extraosseous localization of sup(99m)Tc-MDP in ganglioneuroblastoma

A 2 1/2-year-old boy with a posterior mediastinal ganglioneuroblastoma was evaluated by bone scintigraphy using sup(99m)Tc-MDP and showed a marked increased uptake in the tumor mass. Although a routine chest X-ray and body CT scan failed to demonstrate calcification, X-ray examination of the removed tumor speciment revealed small scattered calcification. The proposed mechanism of the radiopharmaceutical localization in benign and malignant tumores other than calcification/mineralization are discussed. Regardless of the mechanism, localization of a bone scanning agent in a tumor provides a rapid, simple, and noninvasive means of demonstrating tumor size, configuration, and the relation of the surrounding structures to the tumor. (orig.)