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F-18 deoxyfluoroglucose (F-18 FDG) positron emission tomography computed tomography (PET CT) is a sensitive method for diagnosis and follow up of lung cancer and lymphoma. Three patients with pulmonary amyloidosis who underwent PET CT scans are reported. Two cases had increased uptake of FDG. In one, the pathologic diagnosis was an underlying lymphoma. The second was diagnosed as localized pulmonary amyloidoma with positive uptake of FDG. The third case, despite having low-grade lymphoma with associated secondary amyloidosis, did not show uptake of FDG. PET CT scans may be positive in pulmonary amyloidosis. This could be related to the B-lymphocytes producing the light chains with varying degrees of malignant transformation of the cells. We conclude that pulmonary amyloidosis should be added as a possible false-positive when suspecting pulmonary malignancy. Nevertheless, when uptake is highly positive, the possibility of amyloid producing lymphoma should be considered.

The spleen is not fixed to its surroundings. Its position may be changed by gastric and colon dilatation, abdominal masses, and abnormalities in the position or structural integrity of the diaphragm. Splenic displacement can also be congenital. The authors describe a patient with fever of unknown origin, in whom Ga-67 localization in the lower left thorax was initially thought to represent lung infection, but was, in fact, a displaced spleen. Splenic displacement should be considered in the differential diagnosis when Ga-67 localization in the left lower thorax is observed.

The scintigraphic evaluation of a rare case of parenchymal malakoplakia in a transplanted kidney is presented. Uptake of Tc-99m DMSA in the involved area was reduced and the Ga-67 uptake was increased.