2-fluoro-2-deoxy-D-glucose positron emission tomography versus conventional imaging for the diagnosis of breast cancer and lymph node metastases.

CONTEXT: Proper preoperative staging is vital in the treatment of breast cancer patients. Fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) and conventional diagnostic modalities including ultrasonography (US), mammography (MG), and magnetic resonance imaging (MRI) play a greater role. AIMS: To evaluate the diagnostic accuracy of FDG-PET in detecting primary breast cancer as compared with US, MG, and MRI, and in axillary lymph nodes (ALNs) staging in Chinese women. SETTINGS AND DESIGN: It is a study of diagnostic accuracy. SUBJECTS AND METHODS: Thirty-one female patients, with biopsy established breast carcinoma, were recruited and analyzed retrospectively. All patients underwent 18F-FDG-PET, MG, US, and MRI. FDG-PET/CT for the diagnosis of primary breast cancer and detecting ALNs metastases were compared with MG, US, and MRI. STATISTICAL ANALYSIS USED: Sensitivity, specificity, positive-predictive value (PPV), and negative-predictive value (NPV) of FDG-PET imaging for primary breast cancers and ALN staging were analyzed using standard statistical analyses. RESULTS: In 31 patients with cytologically established invasive breast carcinoma, the sensitivities of US, MG, MRI, and FDG-PET/CT were 90% (28/31), 84% (26/31), 97% (30/31), and 94% (29/31), respectively. The sensitivity, specificity, overall accuracy, PPV, and NPV of US, MRI, and FDG-PET/CT in ALN staging (maximum standardized uptake value cutoff at 1.5) were 80%, 86%, 84%, 80%, and 90%; 90%, 95%, 94%, 90%, and 95%; and 90%, 86%, 87%, 90%, and 95%, respectively. CONCLUSIONS: US and MRI should remain the first line for the diagnosis of breast cancer. Both MRI and FDG-PET/CT could accurately diagnose the primary breast cancer and stage the axilla lymph nodes, but further large population study is needed.

Muscular damage in a patient with hepatitis B induced by beta-l-2'-deoxythymidine and detected by 18F-FDG PET/CT.

A 58 years old man under 2'-Deoxy-L-thymidine treatment for his hepatitis B was admitted to our hospital complaining for the last 2 months of recurrent upper abdomen discomfort, fatigue and weight loss of 10 kilograms and general muscular soreness, for 2 weeks. He had elevated creatine kinase (CK), myoglobin, CK-MB and other related or common laboratory findings. Fluorine-18- fluorodeoxyglucose positron emission tomography/ computed tomography (18F-FDG PET/CT) showed a diffuse, homogenous, moderately elevated glucose uptake in all muscle groups. Muscular damage induced by 2'-Deoxy-L-thymidine was suspected and the drug was discontinued. Muscle soreness and the biomarkers for muscular tissue damage improved. Fluorine-18-FDG PET/CT is useful to rule out malignancy and identify muscular tissue damage.

A pediatric malignant paraganglioma and brief review of the literature.

A 10 years old boy presented to our hospital complaining of belly pain. He had a retroperitoneal mass diagnosed by ultrasound 3 days before. During that time he was found to have slight hypertension. Computed tomography (CT) showed a left retroperitoneal mass with edge enhancement and central necrosis indicating pheochromocytoma (PCC). Vanillymandelic acid (VMA) in the 24 hours urine sample was not elevated. Pheochromocytoma was suspected given his hypertension and the ultrasound and CT findings. Fluorine-18- fluorodeoxy glucose positron emission tomography (18F-FDG PET) showed intense uptake in the left adrenal area (SUVmax 32.9) with a central 18F-FDG uptake defect. Subsequently, left adrenalectomy was successfully performed. Histological examination showed that the tumor was a paraganglioma (PGL) with low-grade malignancy. CONCLUSION: Fluorine-18-FDG PET is a highly sensitive method to detect PGL, but could not make a differential diagnosis between PGL and PCC although high uptake of 18F-FDG may indicate malignancy. As our case clearly demonstrates, rare cases of PCC or PGL should be considered in the setting of secondary hypertension.

Pulsed electrical stimulation protects neurons in the dorsal root and anterior horn of the spinal cord after peripheral nerve injury.

Most studies on peripheral nerve injury have focused on repair at the site of injury, but very few have examined the effects of repair strategies on the more proximal neuronal cell bodies. In this study, an approximately 10-mm-long nerve segment from the ischial tuberosity in the rat was transected and its proximal and distal ends were inverted and sutured. The spinal cord was subjected to pulsed electrical stimulation at T10 and L3, at a current of 6.5 mA and a stimulation frequency of 15 Hz, 15 minutes per session, twice a day for 56 days. After pulsed electrical stimulation, the number of neurons in the dorsal root ganglion and anterior horn was increased in rats with sciatic nerve injury. The number of myelinated nerve fibers was increased in the sciatic nerve. The ultrastructure of neurons in the dorsal root ganglion and spinal cord was noticeably improved. Conduction velocity of the sciatic nerve was also increased. These results show that pulsed electrical stimulation protects sensory neurons in the dorsal root ganglia as well as motor neurons in the anterior horn of the spinal cord after peripheral nerve injury, and that it promotes the regeneration of peripheral nerve fibers.