Usefulness of splenic scintigraphy in differentiating splenosis and malignancy on gallium 68 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-NaI3-octreotide

Somatostatin receptor (SSTR) imaging with gallium 68 (Ga-68) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptide positron emission tomography/computed tomography (PET/CT) has been introduced in clinical routine for the diagnosis and staging of neuroendocrine tumors (NETs) with high SSTR expression. Although it has high sensitivity for NETs, there are some known diagnostic pitfalls one should be aware of. We present a case of suspected NET where Ga-68 DOTA-NaI3-octreotide (NOC) PET/CT showed several abdominal lesions with high SSTR expression suggesting malignancy. On magnetic resonance imaging, the differential diagnosis of the lesions also included splenosis. Subsequent splenic scintigraphy with technetium-99m phytate showed uptake in all suspicious lesions, and biopsy confirmed the diagnosis of splenosis. Splenic scintigraphy with single-photon emission computed tomography/CT can be a helpful noninvasive diagnostic tool when splenosis is suspected on Ga-68 DOTA-peptide PET/CT.

Keywords

Gallium 68 1 - 4 - 7 - 10-tetraazacyclododecane-1 - 4 - 7 - 10-tetraacetic acid-NaI3-octreotide - neuroendocrine tumor - splenic scintigraphy - splenosis