Misleading steal phenomenon of Ga-67 uptake by the spleen in a patient with sarcoidosis

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. Most frequently, sarcoidosis presents with bilateral hilar lymphadenopathy and pulmonary infiltration. Histologically, the spleen is the second most commonly involved organ, but splenomegaly is uncommon and massive splenomegaly is rare. Ga-67 scintigraphy has been widely used in the clinical evaluation of sarcoidosis. We describe a patient with a clinical diagnosis of sarcoidosis, in whom Ga-67 scintigraphy showed intense uptake by the massively enlarged spleen, with no additional pathologic uptake, findings which were interpreted as splenic involvement by malignant lymphoma. However, diagnostic splenectomy revealed the diagnosis of splenic involvement by sarcoidosis. A follow-up Ga-67 scan revealed mediastinal, salivary and lacrimal gland uptake typical for sarcoidosis. The authors conclude that any unexpected Ga-67 uptake pattern should be interpreted cautiously in correlation with available clinical data.