Biliary papillomatosis is a rare disease with high malignant potential. A 64-year-old woman underwent FDG PET/CT, which showed an intense FDG uptake in the location of an aggregated biliary papillomatosis with high-grade intraepithelial neoplasia/carcinoma in situ but did not show FDG uptake in the sporadic, small biliary papilloma. FDG PET/CT may be an effective method to identify the components of the malignant transformation of biliary papillomatosis.
A 7-year-old boy presented with diffuse bone pain. FDG PET/CT was performed to find the possible underlying malignant cause of hypercalcemia. The images demonstrated multiple foci of abnormal FDG activity at the sites of periosteal reaction. In addition, calcium deposit was noted in the basal ganglia, stomach, and the colon. History taking revealed that the patient had routinely taken an over-the-counter “supplement” that contains a high dose of vitamin D. One week after calcitonin therapy and stopping the supplement, the patient became symptom free. This case suggests that hypervitaminosis D might cause hypermetabolic periosteal reaction on FDG PET/CT imaging.
Schwannoma is a slow-growing benign tumor, which originates from Schwann cells and is usually asymptomatic. The most common sites of schwannomas are the head, neck, and extremities. However, a schwannoma located in the liver is extremely rare. Here, we report a 53-year-old woman with a hepatic lesion accidentally found by ultrasound. It was highly suggestive of hepatic cholangiocarcinoma by MRI. 18F-FDG PET/CT could not exclude hepatic malignant tumor due to its high metabolism. Finally, it was confirmed as hepatic schwannoma by postoperative pathology.
Incidental tracer uptake on DOTATATE PET is increasingly encountered in clinical practice. We describe 3 patients with suspected or known neuroendocrine tumor who were found to have diffuse and intense stomach uptake on DOTATATE PET. All patients underwent esophagogastroduodenoscopy and/or endoscopic ultrasound; the cause of the stomach uptake was attributed to proton-pump inhibitor use, chronic gastritis, and gastrinoma, respectively. These 3 cases highlight that diffuse and intense stomach DOTATATE uptake can be a benign finding probably attributed to proton-pump inhibitor use, chronic gastritis, or gastrinoma.
A 55-year-old woman with papillary thyroid carcinoma under total thyroidectomy and cervical lymph node dissection was referred for 131I radioiodine therapy. Posttherapeutic whole-body scintigraphy revealed increased focal uptake in the right upper abdomen, which localized to the region of the head of the pancreas on SPECT/CT fusion images. Further evaluation with MRI affirmed the radioiodine retention corresponded to bile duct dilation.
We report 2 cases where blood-pool SPECT/CT had a high added value compared with standard 3-phase bone scintigraphy with only delayed SPECT/CT for the etiological diagnosis of painful ankles. Two men, aged 48 and 62 years, were referred for suspicions of medial and lateral malleoli stress fractures, respectively. Although standard planar blood-pool imaging and delayed SPECT/CT were inconclusive, blood-pool SPECT/CT showed markedly increased uptake along posterior tibial tendon and peroneal tendon, respectively, leading to diagnose tendonitises. These cases illustrate that blood-pool SPECT/CT can extend the diagnostic yield of bone scintigraphy to extraosseous origin, particularly in chronic lower extremities pain.
Esophagectomy with extended lymph node (LN) dissection is a standard treatment for resectable esophageal cancer to prevent recurrence, but severe, potentially life-threatening postoperative complications are still important issues. Accurate diagnosis of LN metastases would enable the decision to dissect or leave the LNs in regions with high risk of complications. Advancements in intraoperative gamma probe and radioactivity detectors have made intraoperative navigation surgery possible using a radiotracer as a marker. 18F-FDG is one such candidate markers, and the diagnostic power of FDG through counting the radioactivity close to each LN should be elucidated.
Materials and Methods
In 20 patients, 1073 LNs including 38 metastatic LNs were prospectively investigated. Preoperative FDG PET was performed on the same day before esophagectomy and visually surveyed in each LN station to identify abnormal uptake. The FDG radioactivity of each individual dissected LN was measured by a well-type counter, and the pathological diagnosis was compared with LN radioactivity on a one-by-one basis and with the preoperative FDG PET findings for each LN station.
Lymph node station-based analysis showed a sensitivity and specificity of 28.6% and 96.7%, respectively. One-by-one LN-based analysis using a cutoff value obtained from the receiver operating characteristic curve showed a sensitivity and specificity of 94.7% and 78.7%, respectively, demonstrating higher accuracy compared with the use of LN weight or the shortest diameter.
The FDG uptake by each LN is a potentially useful marker for navigation surgery in esophageal cancer and has higher accuracy than LN weight or diameter.