68Ga-DOTATATE PET in neuroectodermal tumours:: First experience

Background and aim Phaeochromocytoma is initially imaged with computed tomography (CT) or magnetic resonance imaging (MRI) but functional imaging is commonly needed to assess disease activity, the presence of metastasis and response to therapy. Traditionally, this is done with I-123-MIBG with good sensitivity and specificity. However, spatial resolution remains limited even with SPECT. We aimed to assess the utility of a new somatostatin analogue PET tracer Ga-68-DOTATATE in the management of phaeochromocytoma. Nuclear Medicine Communications Methods We retrospectively reviewed five patients with malignant phaeochromocytoma who underwent imaging with CT and I-123-MIBG and compared the results with those of PET imaging using Ga-68-DOTATATE. Blinded analysis of the numbers and extent of lesions were done for all imaging modality. Results Two patients had negative I-123-M IBG and positive Ga-68-DOTATATE scans. One had a weakly positive I-123-MIBG and a strongly positive Ga-68-DOTATATE scan. One had a positive I-123-M IBG and positive Ga-68-DOTATATE scans. The fifth patient was negative to all imaging including CT. Ga-68-DOTATATE showed more lesions with higher uptake and better resolution compared to I-123-MIBG. Conclusion The findings in our small group of patients demonstrate the value of somatostatin receptor PET imaging in malignant phaeochromocytoma. In lesions with no or low MIBG uptake, the next investigation of choice should be PET imaging with Ga-68-DOTATATE, in view to therapy with Y-90-labelled DOTATATE. Nucl Med Commun 28:359-363 (c) 2007 Lippincott Williams & Wilkins.