Background: The only potential cure for neuroendocrine tumors (NETs) is operative resection, which may also offer a survival benefit for advanced disease. We aimed to assess the role of 68Ga-DOTATATE PET/CT in preoperative planning and compared its performance to CT with IV contrast and MRI with Eovist®, for abdominal NETs.
Methods: Records of patients who underwent 68Ga-DOTATATE PET/CT in addition to MRI with Eovist® and/or CT with IV contrast were retrospectively evaluated. The effect of imaging findings on surgical management and characteristics of detected lesions were analyzed. Descriptive statistics were used.
Results: Of 21 patients who underwent 68Ga-DOTATATE PET/CT prior to surgical resection, five (24%) had a change in surgical management due to findings. In three patients, 68Ga-DOTATATE PET/CT identified the primary tumor. In two patients, 68Ga-DOTATATE PET/CT helped clarify equivocal hepatic lesions seen on MRI with Eovist®. MRI with Eovist® had the highest number of lesions found (median 13, versus 9 on CT and 9.5 on 68Ga-DOTATATE PET/CT). DOTATATE-avid lesions were on average larger than lesions seen only on MRI with Eovist® (1.6 cm versus 0.6 cm, p = 0.0002). The optimal cutoff point for detection by 68Ga-DOTATATE PET/CT was a size of 0.95 cm, with a sensitivity of 56% and specificity of 98%.
Conclusions: Preoperative 68Ga-DOTATATE PET/CT is useful only in a subset of patients undergoing surgical resection for NETs. MRI with Eovist® is superior at identifying liver metastases when compared to 68Ga-DOTATATE PET/CT and should therefore be used routinely before hepatic cytoreduction of NETs.