Javad Azadi

Optimum Lean Body Formulation for Correction of Standardized Uptake Value in PET Imaging

Standardized uptake value (SUV) normalized by lean body mass ([LBM] SUL) is becoming a popular metric for quantitative assessment of clinical PET. Sex-specific quantitative effects of different LBM formulations on liver SUV have not been well studied. Methods: 18F-FDG PET/CT scans from 1,033 consecutive adult (501 women, 532 men) studies were reviewed. Liver SUV was measured with a 3-cm-diameter spheric region of interest in the right hepatic lobe and corrected for LBM using the sex-specific James and Janmahasatian formulations. Results: Body weight was 71.0 ± 20.7 kg (range, 18.0–175.0 kg) and 82.9 ± 18.6 kg (range, 23.0–159.0 kg) for women and men, respectively. SUV, based on body weight, has a significantly positive correlation with weight for both women (r = 0.58, P < 0.0001) and men (r = 0.54, P < 0.0001). This correlation is reduced in men (r = 0.11, P = 0.01) and becomes negative for women (r = −0.35, P = 0.0001) with the James formulation of SUL. This negative correlation was eliminated when the very obese women (body mass index ≥ 35) were excluded from the analysis (r = 0.13, P = 0.8). The Janmahasatian formulation annuls the correlation between SUL and weight for women (r = 0.04, P = 0.4) and decreases it for men (r = 0.13, P = 0.003). Conclusion: Hepatic correction with the more common James formulation for body lean mass breaks down and shows low SUL values in very obese patients. The adoption of the Janmahasatian formula for estimation of LBM in modern PET scanners and display workstations is recommended, in view of the increasing frequency of obesity.

Local delivery of cancer-cell glycolytic inhibitors in high-grade glioma

BACKGROUNDn3-bromopyruvate (3-BrPA) and dichloroacetate (DCA) are inhibitors of cancer-cell specific aerobic glycolysis. Their application in glioma is limited by 3-BrPAs inability to cross the blood-brain-barrier and DCAs dose-limiting toxicity. The safety and efficacy of intracranial delivery of these compounds were assessed.nnnMETHODSnCytotoxicity of 3-BrPA and DCA were analyzed in U87, 9L, and F98 glioma cell lines. 3-BrPA and DCA were incorporated into biodegradable pCPP:SA wafers, and the maximally tolerated dose was determined in F344 rats. Efficacies of the intracranial 3-BrPA wafer and DCA wafer were assessed in a rodent allograft model of high-grade glioma, both as a monotherapy and in combination with temozolomide (TMZ) and radiation therapy (XRT).nnnRESULTSn3-BrPA and DCA were found to have similar IC50 values across the 3 glioma cell lines. 5% 3-BrPA wafer-treated animals had significantly increased survival compared with controls (P = .0027). The median survival of rats with the 50% DCA wafer increased significantly compared with both the oral DCA group (P = .050) and the controls (P = .02). Rats implanted on day 0 with a 5% 3-BrPA wafer in combination with TMZ had significantly increased survival over either therapy alone. No statistical difference in survival was noted when the wafers were added to the combination therapy of TMZ and XRT, but the 5% 3-BrPA wafer given on day 0 in combination with TMZ and XRT resulted in long-term survivorship of 30%.nnnCONCLUSIONnIntracranial delivery of 3-BrPA and DCA polymer was safe and significantly increased survival in an animal model of glioma, a potential novel therapeutic approach. The combination of intracranial 3-BrPA and TMZ provided a synergistic effect.

F-18 FDG PET/CT and Tc-99m Sulfur Colloid SPECT imaging in the diagnosis and treatment of a case of dual solitary fibrous tumors of the retroperitoneum and pancreas

Although FDG PET is increasingly used for the staging of many types of sarcoma, little has been written regarding the FDG PET imaging characteristics of solitary fibrous tumor. We report a patient undergoing FDG PET/CT surveillance for squamous cell carcinoma of the tongue who was incidentally found to have two soft tissue masses in the retroperitoneum and pancreatic tail. Due to their low degree of FDG avidity, they were followed conservatively for approximately one year as they gradually increased in size. Technetium-99m sulfur colloid SPECT helped confirm that the pancreatic tail mass was not a splenule, after which both lesions were surgically resected and found to be extrathoracic solitary fibrous tumors without malignant features. These findings suggest that, as with other low-grade sarcomas, benign extrathoracic solitary fibrous tumors exhibit relatively little glycolytic metabolism in vivo.

Case 61: Renal Cell Carcinoma Metastatic to the Pancreas

76-year-old woman with a history of renal cell carcinoma and underwent radical left nephrectomy 15 years ago. A CT was performed for surveillance.

Case 66: Pseudomass of the Pancreas Associated with Bowel Malrotation

57-year-old woman with incidentally discovered pancreatic head mass for work-up of myasthenia gravis

Case 64: Hypervascular Serous Cystadenoma

45-year-old woman was incidentally found to have a pancreatic tail mass during follow-up CT after recent pelvic surgery.

Case 19: Breast Cancer Metastatic to the Pancreas

35-year-old woman with history of invasive ductal carcinoma was status post left radical mastectomy 2 years ago. She presented with acute abdominal pain and a serum lipase of 279 U/L (normal, 16–63 U/L).