Extensive soft-tissue involvement of dermatomyositis detected by whole-body scintigraphy with 99mTc-MDP and 201TL-chloride.

The authors present a case of extensive soft-tissue radioactivity visualized on both 99mTc-MDP and 201Tl-chloride scintigrams in a patient with dermatomyositis and colon cancer. Incidentally, diffuse and intense uptake of 99mTc-MDP was observed in the shoulder girdles, anterior chest wall, psoas muscles, both proximal thighs and right lower limb, corresponding to the sites of symptomatic muscles, even though skin lesions were limited and no calcification was detected on radiographs. Moreover, 201Tl-chloride was also intensely accumulated in nearly the same sites as the symptomatic muscles as shown on the 99mTc-MDP bone scintigrams. Whole-body scintigraphy with 99mTc-MDP and 201Tl-chloride is a useful tool to detect occult muscle lesions with dystrophic calcification and hyperemia in dermatomyositis.