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Ga-labeled prostate-specific membrane antigen inhibitors and Ga-labeled gastrin-releasing peptide receptor antagonists showed interesting results for staging biochemically recurrent prostate cancer. In this case, Ga-prostate-specific membrane antigen-617 PET/CT, Ga-RM2 PET/CT, and F-choline PET/CT were performed in a patient (66-year-old man, prostate-specific antigen = 6.7 ng/mL) with biopsy-proven Gleason 9 (5 + 4) prostate cancer, candidate for radical prostatectomy and lymph node dissection.

Introduction: When evaluating response of Hodgkin lymphoma (HL) to chemotherapy on interim (18)F-FDG-PET/CT, physiological liver uptake is used as reference. Hodgkin lymphoma sites with uptake greater than liver are interpreted as positive. We aimed at examining factors that might influence liver uptake as reference organ., Methods: Fifty patients with HL who received baseline (18)F-FDG-PET/CT (PET1) and interim PET (PET2), usually after 2 cycles of adriamycin bleomycin, vinblastine, and dacarbazine chemotherapy, were included retrospectively. SUVmean normalized for body weight (SUVmean) and for lean body mass (SULmean) were obtained from regions of interest in the right lobe of the liver., Results: On univariate analysis, liver SUVmean on interim PET increased with increasing body mass index (BMI) (P = 0.0453) and were higher in women (P = 0.0401). These factors remained significant on multivariate analysis (P = 0.009 and P = 0.008, respectively). No significant correlation was found with postinjection delay, blood glucose level, and age. Liver SULmean were not affected by the studied variables. Average liver SUVmean in the 50 patients were similar at baseline and interim PET. In 11 patients (22%), however, there was 30% or greater variation in liver SUVmean between PET1 and PET2. No factors explaining intrapatient variation in hepatic uptake between PET1 and PET2 were found on correlation analysis., Conclusion: At interim PET in patients with HL, liver SUVmean depends on BMI and sex, but not liver SULmean. Furthermore, our study, conducted with standard clinical procedure, also confirmed the high range of liver uptake values from one patient to another. Caution is required when using liver SUV as reference in patients with high BMI. Intrapatient fluctuation in liver SUVmean should also be expected.

SPECT/CT reinforces the role of lymphoscintigraphy in breast cancer by solving some cases with difficult reading on planar scintigraphy. An 80-year-old woman was referred to our institution for management of a screen-detected, nonpalpable, invasive lobular carcinoma of lower inner quadrant of the left breast. Lymphoscintigraphy was performed before surgery. Planar images showed an axillary sentinel node and 2 medially located hot spots. SPECT/CT allowed determining that one of the extra-axillary drainage sites was to the internal mammary basin, while the second corresponded to a mediastinal lymph node. Although this drainage was unexpected, mediastinum is a common site of breast cancer recurrence.

Secondary hyperparathyroidism (sHPT) is a major complication for patients with end-stage renal disease on long-term hemodialysis or peritoneal dialysis. When the disease is resistant to medical treatment, patients with severe sHPT are typically referred for parathyroidectomy (PTx), which usually improves biological parameters as well as clinical signs and symptoms. Unfortunately, early surgical failure with persistent disease may occur in 5%-10% of patients and recurrence reaches 20%-30% at 5 years. Presently, the use of parathyroid scintigraphy in sHPT is usually limited to the management of surgical failures after initial PTx. This review describes the strengths and limitations of typical (99m)Tc-sestamibi imaging protocols, and highlights the potential benefits of using parathyroid scintigraphy in the initial workup of surgical patients.

Purpose: It has been proposed to use liver as reference organ when assessing tumor response with PET. We investigated whether liver FDG uptake is dependent on clinical, biological, or technical factors., Methods: Sixty-one women with breast carcinoma had FDG-PET/CT imaging at baseline and then after the second course of neoadjuvant chemotherapy. SUV values were measured over the primary breast tumor and in a region of interest of 30-mm diameter within the liver., Results: Liver SUVmean values for the 61 women were not different before and after the 2 courses of chemotherapy (2.27 vs 2.35; P = 0.18). No significant correlation was found between the delay postinjection and liver SUV. Liver SUVmean increased with blood glucose level (P = 0.007 on baseline PET studies, and P = 0.067 on postchemotherapy studies). Liver SUVmean increased significantly with increasing patient age, which was observed on baseline (P = < 0.001) and postchemotherapy studies (P = 0.002). Again, liver SUVmean increased with body weight (P = 0.037 on baseline studies and 0.003 on postchemotherapy studies). On multivariate analysis, 2 independent variables remained correlated to liver SUV, namely, age and weight. We found no statistically significant correlation between the studied physiological variables and breast tumor SUVmax. However, there was a trend for lower SUVmax with increasing blood glucose level or age., Conclusions: FDG liver uptake depends on many factors such as age, weight, and blood glucose level. Some of these variables seem to have an opposite impact on tumor SUVmax. These findings challenge the usefulness of liver as reference.

Purpose: Our aims were to assess the feasibility of imaging hypoxia in cervical carcinoma with (18)F-fluoroerythronitroimidazole ((18)F-FETNIM) and to compare (18)F-FETNIM uptake with metabolic uptake of (18)F-FDG., Patients and Methods: We included 16 patients with cervical carcinoma. After imaging with FDG, (18)F-FETNIM PET/CT was performed and tumor-to-muscle (T/M) ratio uptake was assessed. (18)F- FETNIM uptake was correlated to FDG uptake and osteopontin (OPN), a marker of hypoxia, and patients' outcomes., Results: All tumors were detected by (18)F-FDG PET. (18)F-FETNIM T/M ratios ranged from 1.3 to 5.4. There was no significant correlation between (18)F-FETNIM and (18)F-FDG uptake. High (18)F-FETNIM uptake (T/M > 3.2) was associated with reduced progression-free survival (log-rank = 0.002) and overall survival (log-rank = 0.02). Osteopontin ranged from 39 to 662 μg/L (median, 102.5 μg/L). Patients with OPN greater than 144 μg/L had reduced progression-free survival compared with those with OPN less than 144 μg/L (log-rank = 0.03). We found no significant correlation between (18)F-FETNIM uptake and OPN blood levels., Conclusions: Our preliminary results showed that a high uptake of (18)F-FETNIM was associated with a worse progression-free and overall survival.

Purpose: Nests of thyroid tissue in the tongue are described in about 10% of necropsies. This ectopic thyroid tissue usually lies dormant, but may manifest itself during times of increased stimulation. The aim of our study was to assess the frequency of lingual thyroid visualization on I-131 diagnostic whole-body scan during the follow-up of thyroid cancer patients., Material and Methods: We reviewed the files of 548 consecutive patients who underwent a diagnostic whole-body scan with 200 MBq of I-131 between January 2000 and December 2005, as part of the follow-up for a differentiated thyroid cancer. Every patient had been previously treated with a total thyroidectomy and had received 3.7 GBq (100 mCi) of I-131 for remnant ablation., Results: A focus of uptake located between the 2 submandibular salivary glands, suggestive of ectopic thyroid tissue in the tongue or in the upper part of the thyroglossal duct, was found in 5 of the 548 patients (0.9%). In only one of these patients was the uptake visible at the time of postsurgery thyroid remnant ablation scan. Thyroglobulin (Tg) levels were positive under stimulation in 3 of the 5 patients, and another patient had undetectable Tg, but positive anti-Tg antibodies. Radiologic imaging (MRI and/or ultrasound) was performed in 3 patients and confirmed the presence of a mass suggestive of ectopic thyroid tissue in two. Invasive lingual biopsy was not performed to verify the benign nature., Conclusion: When examining whole-body scans (therapeutic or diagnostic) in a patient with persistent Tg detection after thyroid ablation, one should carefully search for any uptake between the submandibular glands that may be suggestive of ectopic tissue.