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Our goal was to validate the feasibility of(99m)Tc-duramycin as a potential apoptosis probe for monitoring tumor response to paclitaxel in breast cancer xenografts. The binding of(99m)Tc-duramycin to phosphatidylethanolamine was validated in vitro using paclitaxel-treated human breast carcinoma MDA-MB-231 cells. Female BALB/c mice (n = 5) bearing breast cancer xenografts were randomized into 2 groups and intraperitoneally injected with 40 mg/kg paclitaxel or phosphate-buffered saline.(99m)Tc-duramycin (37-55.5 MBq) was injected at 72 hours posttreatment, and single-photon emission computed tomography/computed tomography was performed at 2 hours postinjection. Apoptotic cells and activated caspase 3 in explanted tumor tissue were measured by flow cytometry. Cellular ultrastructural changes were assessed by light and transmission electron microscopy.(99m)Tc-duramycin with radiochemical purity of >90% exhibited rapid blood clearance and predominantly renal clearance. The tumor-to-muscle ratio in the paclitaxel-treated group (5.29 ± 0.62) was significantly higher than that in the control. Tumor volume was decreased dramatically, whereas tumor uptake of(99m)Tc-duramycin (ex vivo) significantly increased following paclitaxel treatment, which was consistent with apoptotic index, histological findings, and ultrastructural changes. Our data demonstrated the feasibility of(99m)Tc-duramycin for early detection of apoptosis after paclitaxel chemotherapy in breast carcinoma xenografts., (© The Author(s) 2016.)

We estimated the dosimetry of (18)F-alfatide II with the method established by MIRD based on biodistribution data of mice. Six mice (three females and three males) were scanned for 160min on an Inveon MicroPET/CT scanner after injection of (18)F-alfatide II via tail vein. Eight source organs were delineated on the CT images and their residence times calculated. The data was then converted to human using scaling factors based on organ and body weight. The absorbed doses for human and the resulting effective dose were computed by OLINDA 1.1 software. The highest absorbed doses was observed in urinary bladder wall (male 0.102mGy/MBq, female 0.147mGy/MBq); and the lowest one was detected in brain (male 0.0030mGy/MBq, female 0.0036). The total effective doses were 0.0127mSv/MBq for male and 0.0166 mSv/MBq for female, respectively. A 370-MBq injection of (18)F-alfatide II led to an estimated effective dose of 4.70mSv for male and 6.14mSv for female. The potential radiation burden associated with (18)F-alfatide II/PET imaging therefore is comparable to other PET examinations., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Whether PET scan maximum standard uptake value (SUVmax) could differentiate luminal A from luminal B and help predict the survival of metastatic breast cancer (MBC) patients with luminal subtype is still unknown and need to be investigated., Methods: 305 MBC patients with luminal subtypes were screened with PET/CT. Eligible patients were prospectively followed up., Results: In total, 134 patients were eligible for this study. SUVmax was significantly related to the number of metastatic sites and presence of visceral metastasis on univariate analysis. SUVmax could not effectively differentiate patients with luminal A from luminal B subtype. Although luminal subtype at diagnosis could predict the relapse-free interval, it could not predict progression-free survival (PFS) or overall survival (OS) after developing relapse. In contrast, SUVmax was predictive of both PFS and OS and this effect was maintained in multivariate COX regression model., Conclusions: SUVmax of MBC did not correlate with molecular subtypes of primary tumor. While molecular subtype may be a valuable prognostic factor at primary diagnosis of breast cancer, the SUVmax, rather than molecular subtype, does have a potential to predict independently in multivariate analysis for the PFS and OS in patients with metastatic disease of luminal subtype.

Purpose: To find optimal threshold of length and GTV delineation for esophageal cancer using 18FDG PET/CT., Materials and Methods: Sixteen patients with esophageal carcinoma underwent surgery. For each patient, six GTVs were defined. GTVCT was based on CT data alone. GTV20%, GTV40%, GTV2.5 and GTV40%M were generated by PET/CT, using SUVbgd + 20%(SUVmax(slice)--SUVbgd), SUVbgd + 40%(SUVmax(slice)--SUVbgd), 2.5 and 40%SUVmax(total) as thresholds. GTVpath was derived from pathology. Lengths of GTVs were recorded as LCT, L20%, L40%, L2.5, L40%M and Lpath, respectively. The former five GTVs/lengths were compared with GTVpath/Lpath by means of a conformity index CI/CI', which is the square of intersection of two GTVs/lengths divided by their product., Results: Mean LCT, L20%, L40%, L2.5, L40%M and Lpath were 6.30 +/- 2.69, 5.55 +/- 2.48, 6.80 +/- 2.92, 6.65 +/- 2.66, 4.88 +/- 1.99 and 5.90 +/- 2.38 cm. Mean , , , and were 0.68 +/- 0.16, 0.84 +/- 0.17, 0.76 +/- 0.14, 0.78 +/- 0.15 and 0.80 +/- 0.11. and was significantly superior to (P < 0.05). Mean GTVCT, GTV20%, GTV40%, GTV2.5, GTV40%M and GTVpath were 29.16 +/- 18.56, 18.75 +/- 12.37, 12.52 +/- 8.08, 22.69 +/- 14.84, 9.18 +/- 5.96 and 28.16 +/- 17.02 cm3. Mean CIs increased significantly from CI40%&path(0.27 +/- 0.09) and CI'40% M&path (0.28 +/- 0.08) < CI'20% & path (0.52 +/- 0.16) and CI'2.5&path (0.52 +/- 0.20) < CICT&path(0.77 +/- 0.17)., Conclusions: The SUVbgd + 20% (SUVmax(slice)--SUVbgd) method optimally estimated gross tumor length, but only reached an unsatisfactory CI for GTV. Due to possible motion factor enveloped in PET images and lack of histopathologic transverse reference, the information from both PET and CT should be referred to complementarily when delineating GTV.

Two cases of postoperative female patients with ovarian serous papillary carcinoma were referred for F-18 Fluorodeoxyglucose (F-18 FDG) PET/CT to evaluate suspicious recurrence and/or metastasis. One patient presented with multiple extensive calcified lesions with increased FDG uptake in the abdominopelvic cavity and the series of PET/CT scans showed progression of disease after chemotherapy. The other patient presented with three calcified masses with intensive uptake of FDG located in the left pelvis, the right subphrenic region, and the right supradiaphragmatic area, respectively. These suggest that F-18 FDG PET/CT can be useful in identifying malignant calcification and assessing therapeutic response of calcified malignancy. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To find optimal threshold of length and GTV delineation for esophageal cancer using 18FDG PET/CT. Materials and methods: Sixteen patients with esophageal carcinoma underwent surgery. For each patient, six GTVs were defined. GTVCT was based on CT data alone. GTV20%, GTV40%, GTV2.5 and GTV40%M were generated by PET/CT, using SUVbgd +20%(SUVmax(slice) −SUVbgd), SUVbgd +40%(SUVmax(slice) −SUVbgd), 2.5 and 40%SUVmax(total) as thresholds. GTVpath was derived from pathology. Lengths of GTVs were recorded as L CT, L 20%, L 40%, L 2.5, L 40%M and L path, respectively. The former five GTVs/lengths were compared with GTVpath/L path by means of a conformity index CI/CI′, which is the square of intersection of two GTVs/lengths divided by their product. Results: Mean L CT, L 20%, L 40%, L 2.5, L 40%M and L path were 6.30±2.69, 5.55±2.48, 6.80±2.92, 6.65±2.66, 4.88±1.99 and 5.90±2.38cm. Mean , , , and were 0.68±0.16, 0.84±0.17, 0.76±0.14, 0.78±0.15 and 0.80±0.11. and was significantly superior to (P <0.05). Mean GTVCT, GTV20%, GTV40%, GTV2.5, GTV40%M and GTVpath were 29.16±18.56, 18.75±12.37, 12.52±8.08, 22.69±14.84, 9.18±5.96 and 28.16±17.02cm3. Mean CIs increased significantly from CI40%&path(0.27±0.09) and CI40%M&path(0.28±0.08)