FDG-pet in paraneoplastic syndromes.

Paraneoplastic syndromes are rare disorders, but recognition is important because clinical manifestations of paraneoplastic syndromes may precede those of the underlying malignancy by months or even years. As tumor therapy still is the mainstay of treatment for paraneoplastic syndromes, early diagnosis of the initial tumor or its recurrence is of utmost clinical importance. For finding the associated tumor, the combined use of FDG-PET and CT seems to have the highest sensitivity and may contribute to accurately distinguishing a true tumor or recurrence from benign lesions or physiologic or inflammatory uptake. Further, this approach helps localize the tumor for further management of the patient such as surgery or more invasive diagnostic procedures. Cerebral FDG-PET proved to confirm paraneoplastic encephalitis and may help monitor tumor therapy.