Use of molecular imaging to differentiate liver metastasis of colorectal cancer metastasis from neuroendocrine tumor origin.

Synchronous malignant neoplasms in a single patient are well documented in the literature. It is also recognized that there is increasing incidence of synchronous non-neuroendocrine neoplasm in patients with neuroendocrine tumor (NET). We present a case, of a patient with synchronous colorectal cancer and pancreatic NET, both cancers presenting with liver metastasis. By using 18F-FDG PET and 68Ga-DOTATATE PET imaging, we showed 2 different tumor types within the liver, which was subsequently confirmed on liver biopsy. This case report shows the utility of molecular imaging using different PET peptides. These newer modalities are useful in understanding the biology of the NET and in determining the best patient management.