Transiently Altered Distribution of F-18 FDG in a Patient with Subacute Thyroiditis.

F-18 fluorodeoxyglucose (FDG) is a highly influential radiotracer that provides valuable information in many cancer types. However, the normal biodistribution of F-18 FDG is often variable and can be altered by intrinsic or iatrogenic factors. We report a case of diffuse symmetrically increased skeletal muscle uptake and relatively decreased hepatic uptake on F-18 FDG PET/CT in a 57-year-old female with pulmonary adenocarcinoma. Detailed clinical evaluation and retrospective radiologic evaluation revealed that she had been diagnosed with subacute thyroiditis 2 weeks ago. After 6 weeks, F-18 FDG distribution was normalized at the follow-up PET/CT study.

Usefulness of Tc-99m Pertechnetate SPECT/CT in the Diagnosis of Testicular Infarction After Inguinal Herniorrhaphy.

A 77-year-old male underwent open repair for a right indirect inguinal hernia and complained of right scrotal pain on the third postoperative day. Color Doppler imaging revealed decreased blood flow with heterogeneous hypoechogenicity in the right testis. A Tc-99m pertechnetate testicular scan showed diffuse hyperemia and increased uptake in the right scrotum. Additional SPECT/CT revealed a photon defect in the right testicle with increased uptake in the peri-testicular area. A subsequent operation revealed a large hematoma in the right spermatic cord and consequent right testicular infarction, and right orchiectomy was performed.

Synthesis and evaluation of Tc-99m and fluorescence-labeled elastin-derived peptide, VAPG for multimodal tumor imaging in murine tumor model.

We developed a Tc-99m and fluorescence-labeled peptide, Tc-99m TAMRA-GHEG-ECG-VAPG to target tumor cells and evaluated the diagnostic performance as a dual-modality imaging agent for tumor in a murine model. TAMRA-GHEG-ECG-VAPG was synthesized by using Fmoc solid-phase peptide synthesis. Radiolabeling of TAMRA-GHEG-ECG-VAPG with Tc-99m was done by using ligand exchange via tartrate. Binding affinity and in vitro cellular uptake studies were performed. Gamma camera imaging, biodistribution, and ex vivo imaging studies were performed in murine models with SW620 tumors. Tumor tissue slides were prepared and analyzed with immunohistochemistry by using confocal microscopy. After radiolabeling procedures with Tc-99m, Tc-99m TAMRA-GHEG-ECG-VAPG complexes were prepared in high yield (>96%). The Kd of Tc-99m TAMRA-GHEG-ECG-VAPG determined by saturation binding was 16.8 ± 3.6 nM. Confocal microscopy images of SW620 cells incubated with TAMRA-GHEG-ECG-VAPG showed strong fluorescence in the cytoplasm. Gamma camera imaging revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-VAPG in tumors. Tumor uptake was effectively blocked by the coinjection of an excess concentration of VAPG. Specific uptake of Tc-99m TAMRA-GHEG-ECG-VAPG was confirmed by biodistribution, ex vivo imaging, and immunohistochemistry stain studies. In vivo and in vitro studies revealed substantial uptake of Tc-99m TAMRA-GHEG-ECG-VAPG in tumor cells. Tc-99m TAMRA-GHEG-ECG-VAPG has potential as a dual-modality tumor imaging agent.

Tc­99m Ser­Asp­Val­Glu­Cys­Gly: A novel Tc­99m labeled hexapeptide for molecular and non­invasive tumor imaging.

In a ProteoChip­based screening system and subsequent studies, serine­aspartic acid­valine (SDV) was demonstrated to specifically bind to integrin αvß3. An SDV­containing peptide could target the tumor vessel and it may be an effective replacement for molecular imaging of the tumor. In the present study, a hexapeptide, SDV­glutamic acid­cysteine­glycine (ECG), was developed and evaluated its diagnostic performance as a tumor imaging agent in tumor­bearing mice. The hexapeptide SDV­ECG was synthesized using Fmoc solid­phase peptide synthesis. Following radiolabeling procedures with technetium­99m, the Tc­99m SDV­ECG complexes were prepared at high yields (>97%). The uptake of Tc­99m SDV­ECG within HT­1080 tumor cells (integrin αvß3­positive) was confirmed by in vitro studies. γ­camera imaging revealed substantial uptake of Tc­99m SDV­ECG in the HT­1080 cell line tumor murine model. With the co­injection of excess SDV, tumoral uptake was blocked. Furthermore, HT­29 tumor cells (integrin αvß3­negative) and inflammatory lesions demonstrated minimal uptake of Tc­99m SDV­ECG. In the present study, Tc­99m SDV­ECG was developed as a novel Tc­99m agent for tumor imaging. The current in vitro and in vivo studies demonstrated specific functions of Tc­99m SDV­ECG in tumor imaging.

A novel Tc-99 m and fluorescence labeled peptide as a multimodal imaging agent for targeting angiogenesis in a murine tumor model.

The serine-aspartic acid-valine (SDV) peptide binds specifically to integrin αV ß3 . In the present study, we successfully developed a TAMRA-GHEG-ECG-SDV peptide labeled with both Tc-99 m and TAMRA to target the integrin αV ß3 of tumor cells; furthermore, we evaluated the diagnostic performance of Tc-99 m TAMRA-GHEG-ECG-SDV as a dual-modality imaging agent for tumor of the murine model. TAMRA-GHEG-ECG-SDV was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling of TAMRA-GHEG-ECG-SDV with Tc-99 m was done using ligand exchange methods. Labeling stability and cytotoxicity studies were performed. Gamma camera imaging, biodistribution and ex vivo imaging studies were performed in murine models with HT-1080 and HT-29 tumors. A tumor tissue slide was prepared and analyzed using confocal microscopy. After radiolabeling procedures with Tc-99 m, the Tc-99 m TAMRA-GHEG-ECG-SDV complexes were prepared in high yield (>99%). In the gamma camera imaging study, a substantial uptake of Tc-99 m TAMRA-GHEG-ECG-SDV into HT-1080 tumor (integrin αV ß3 positive) and low uptake of Tc-99 m TAMRA-GHEG-ECG-SDV into HT-29 tumor (integrin αV ß3 negative) were demonstrated. A competition study revealed that HT-1080 tumor uptake was effectively blocked by the co-injection of an excess concentration of SDV. Specific uptake of Tc-99 m TAMRA-GHEG-ECG-SDV was confirmed by biodistribution, ex vivo imaging and confocal microscopy studies. Our in vivo and in vitro studies revealed substantial uptake of Tc-99 m TAMRA-GHEG-ECG-SDV in the integrin αV ß3 -positive tumor. Tc-99 m TAMRA-GHEG-ECG-SDV could be a good candidate for a dual-modality imaging agent targeting tumor angiogenesis. Copyright © 2016 John Wiley & Sons, Ltd.

Preclinical evaluation of isostructural Tc-99m- and Re-188-folate-Gly-Gly-Cys-Glu for folate receptor-positive tumor targeting.

OBJECTIVE: The purpose of the present study was to prepare isostructural Tc-99m- and Re-188-folate-Gly-Gly-Cys-Glu (folate-GGCE), and to evaluate the feasibility of their use for folate receptor (FR)-targeted molecular imaging and as theranostic agents in a mouse tumor model. METHODS: Folate-GGCE was synthesized using solid-phase peptide synthesis and radiolabeled with Tc-99m or Re-188. Radiochemical characterization was performed by radio-high-performance liquid chromatography. The biodistribution of Tc-99m-folate-GGCE was studied, with or without co-injection of excess free folate, in mice bearing both FR-positive (KB cell) and FR-negative (HT1080 cell) tumors. Biodistribution of Re-188-folate-GGCE was studied in mice bearing KB tumors. Serial planar scintigraphy was performed in the dual tumor mouse model after intravenous injection of Tc-99m-folate-GGCE. Serial micro-single photon emission computed tomography/computed tomography (SPECT/CT) studies were performed, with or without co-injection of excess free folate, in the mouse tumor model after injection of Tc-99m-folate-GGCE or Re-188-folate-GGCE. RESULTS: The radiolabeling efficiency and radiochemical stability of Tc-99m- and Re-188-folate-GGCE were more than 95 % for up to 4 h after radiolabeling. Uptake of Tc-99m-folate-GGCE at 1, 2, and 4 h after injection in KB tumor was 16.4, 23.2, and 17.6 % injected dose per gram (%ID/g), respectively. This uptake was suppressed by 97.4 % when excess free folate was co-administered. Tumor:normal organ ratios at 4 h for blood, liver, lung, muscle, and kidney were 54.3, 25.2, 38.3, 97.8, and 0.3, respectively. Tumor uptake of Re-188-folate-GGCE at 2, 4, 8, and 16 h after injection was 17.4, 21.7, 24.1, and 15.6 %ID/g, respectively. Tumor:normal organ ratios at 8 h for blood, liver, lung, muscle, and kidney were 126.8, 21.9, 54.8, 80.3, and 0.4, respectively. KB tumors were clearly visualized at a high intensity using serial scintigraphy and micro-SPECT/CT in mice injected with Tc-99m- or Re-188-folate-GGCE. The tumor uptake of these molecules was completely suppressed when excess free folate was co-administered. CONCLUSION: Isostructural Tc-99m- and Re-188-folate-GGCE showed high and FR-specific uptake by tumors and generally favorable tumor:normal organ ratios. The tumor targeting capabilities of Tc-99m- and Re-188-folate-GGCE were clearly evident on serial imaging studies. This isostructural pair may have potential diagnostic and theranostic applications for FR-positive tumors.

Tc-99m Glu-Cys-Gly-His-Gly-Lys (ECG-HGK), a novel Tc-99m labeled hexapeptide for molecular tumor imaging.

Domain 5 of kinin-free high molecular weight kininogen inhibits the adhesion of many tumor cell lines, and it has been reported that the histidine-glycine-lysine (HGK)-rich region might be responsible for inhibition of cell adhesion. The authors developed HGK-containing hexapeptide, glutamic acid-cysteine-glycine (ECG)-HGK, and evaluated the utility of Tc-99m ECG-HGK for tumor imaging. Hexapeptide, ECG-HGK was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling efficiency was evaluated. The uptake of Tc-99m ECG-HGK within HT-1080 cells was evaluated in vitro. In HT-1080 tumor-bearing mice, gamma imaging and biodistribution studies were performed. The complexes Tc-99m ECG-HGK was prepared in high yield. The uptake of Tc-99m ECG-HGK within the HT-1080 tumor cells had been demonstrated by in vitro studies. The gamma camera imaging in the murine model showed that Tc-99m ECG-HGK was accumulated substantially in the HT-1080 tumor (tumor-to-muscle ratio = 5.7 ± 1.4 at 4 h), and the tumoral uptake was blocked by the co-injection of excess HGK (tumor-to-muscle ratio = 2.8 ± 0.6 at 4 h). In the present study, Tc-99m ECG-HGK was developed as a new tumor imaging agents. Our in vitro and in vivo studies revealed specific function of Tc-99m ECG-HGK for tumor imaging.

Incidental Detection of Urinary Leakage on FDG PET/CT Imaging for Staging of Gastric Cancer.

A 71-year-old woman presented to the emergency department with right flank pain and dysuria. An abdominal CT scan detected a gastric malignancy and hydronephrosis with urinary leakage of the right kidney. Percutaneous nephrostomy was performed on the right kidney. F-FDG PET/CT for staging the gastric malignancy revealed additional urinary leakage of the contralateral kidney. The interest in this case is the incidental detection of unexpected urinary leakage during an oncologic assessment with FDG PET/CT.

Synthesis and Evaluation of (99m)Tc-Labeled Folate-Tripeptide Conjugate as a Folate Receptor-Targeted Imaging Agent in a Tumor-Bearing Mouse Model.

PURPOSE: The folate receptor (FR) is an attractive molecular target since it is overexpressed in a variety of human tumors. The purpose of the present study was to synthesize and evaluate the feasibility of a novel (99m)Tc-ECG-EDA (Glu-Cys-Gly-ethylenediamine)-folate as an FR-positive tumor imaging agent in a mouse tumor model. MATERIALS AND METHODS: ECG-EDA-folate was synthesized using solid phase peptide synthesis (SPPS) and radiolabeled with (99m)Tc using tripeptide ECG as a chelator. FR-positive KB cells were inoculated in athymic nude mice. Following injection of (99m)Tc-ECG-EDA-folate, serial scintigraphy and micro-SPECT/CT imaging were performed at various time points with and without pre-administration of excess free folate. Mean count densities (MCD) for regions of interest drawn on KB tumors and major normal organs at each time point were measured, and uptake ratios of tumor to normal organs were calculated. RESULTS: ECG-EDA-folate was labeled with (99m)Tc with high radiolabeling efficiency and stability (>96 %). FR-positive tumors were clearly visualized on both scintigraphy and micro-SPECT/CT images and the tumor uptake of (99m)Tc-ECG-EDA-folate was markedly suppressed with faint visualization of tumors by pre-administration of excess free folate on serial planar scintigraphy, indicating FR-specific binding of the agent. Furthermore, semiquantitative analysis of MCD data showed again that both tumor MCD and tumor-to-normal organ ratios decreased considerably by pre-administration of excess free folate, supporting FR-specific tumor uptake. Tumor-to-normal organ ratios approximately increased with time after injection until 4 h. CONCLUSION: The present study demonstrated that (99m)Tc-ECG-EDA-folate can bind specifically to FR with clear visualization of FR-positive tumors in a mouse tumor model.

Synthesis and evaluation of Tc-99m-labeled RRL-containing peptide as a non-invasive tumor imaging agent in a mouse fibrosarcoma model.

OBJECTIVE: Arginine-arginine-leucine (RRL) is considered a tumor endothelial cell-specific binding sequence. RRL-containing peptide targeting tumor vessels is an excellent candidate for tumor imaging. In this study, we developed RRL-containing hexapeptides and evaluated their feasibility as a tumor imaging agent in a HT-1080 fibrosarcoma-bearing murine model. METHODS: The hexapeptide, glutamic acid-cysteine-glycine (ECG)-RRL was synthesized using Fmoc solid-phase peptide synthesis. Radiolabeling efficiency was evaluated using instant thin-layer chromatography. Uptake of Tc-99m ECG-RRL within HT-1080 cells was evaluated in vitro by confocal microscopy and cellular binding affinity was calculated. Gamma images were acquired In HT-1080 fibrosarcoma tumor-bearing mice, and the tumor-to-muscle uptake ratio was calculated. The inflammatory-to-normal muscle uptake ratio was also calculated in an inflammation mouse model. A biodistribution study was performed to calculate %ID/g. RESULTS: A high yield of Tc-99m ECG-RRL complexes was prepared after Tc-99m radiolabeling. Binding of Tc-99m ECG-RRL to tumor cells had was confirmed by in vitro studies. Gamma camera imaging in the murine model showed that Tc-99m ECG-RRL accumulated substantially in the subcutaneously engrafted tumor and that tumoral uptake was blocked by co-injecting excess RRL. Moreover, Tc-99m ECG-RRL accumulated minimally in inflammatory lesions. CONCLUSIONS: We successfully developed Tc-99m ECG-RRL as a new tumor imaging candidate. Specific tumoral uptake of Tc-99m ECG-RRL was evaluated both in vitro and in vivo, and it was determined to be a good tumor imaging candidate. Additionally, Tc-99m ECG-RRL effectively distinguished between cancerous tissue and inflammatory lesions.

Synthesis and evaluation of novel Tc-99m labeled NGR-containing hexapeptides as tumor imaging agents.

Asparagine-glycine-arginine (NGR)-containing peptides targeting aminopeptidase N (APN)/CD13 can be an excellent candidate for targeting ligands in molecular tumor imaging. In this study, we developed two NGR-containing hexapeptides, and evaluated the diagnostic performance of Tc-99m labeled hexapeptides as molecular imaging agents in an HT-1080 fibrosarcoma-bearing murine model. Peptides were synthesized using Fmoc solid-phase peptide synthesis. Radiochemical purity of Tc-99m was evaluated using instant thin-layer chromatography. The uptake of two NGR-containing hexapeptides within HT-1080 cells was evaluated in vitro. In HT-1080 fibrosarcoma tumor-bearing mice, gamma images were acquired. A biodistribution study was performed to calculate percentage of the injected dose per gram of tissue (%ID/g). Two hexapeptides, glutamic acid-cysteine-glycine (ECG)-NGR and NGR-ECG were successfully synthesized. After radiolabeling procedures with Tc-99m, the complexes Tc-99m hexapeptides were prepared in high yield. The uptake of Tc-99m ECG-NGR within the tumor cells had been assured by in vitro studies. The gamma camera imaging in the murine model showed that Tc-99m ECG-NGR was accumulated substantially in the subcutaneously engrafted tumor. However, Tc-99m NGR-ECG was accumulated minimally in the tumor. Two NGR-containing hexapeptides, ECG-NGR and NGR-ECG were developed as molecular imaging agents to target APN/CD13 in HT-1080 fibrosarcoma. Tc-99m ECG-NGR showed a significant uptake in the tumor, and it is a good candidate for tumor imaging.

Lymphoscintigraphy revealed chyloperitoneum after gastrectomy for gastric cancer.

A 74-year-old woman underwent the radical near-total gastrectomy with Billroth II anastomosis and lymph nodes dissection due to the advanced gastric cancer. On the seventh day after gastrectomy, edema on the both legs and abdominal distention were developed. On the lymphoscintigraphy, the abnormal activity in the peritoneal cavity was revealed, and chyloperitoneum was diagnosed, and additional dynamic scans could localize the chyle leakage focus. Localization of chyle leakage focus enabled surgeon to establish the proper operative plan for the injured lymphatics.

Synthesis and evaluation of Tc-99m DTPA-glutathione as a non-invasive tumor imaging agent in a mouse colon cancer model.

PURPOSE: Glutathione (GSH) plays a critical role in detoxification reactions by reducing the levels of reactive oxygen species in cancer cells. This study aimed to develop technetium (Tc)-99m diethylenetriaminepentaacetic acid (DTPA)-GSH as a tumor imaging agent, and to evaluate the diagnostic performance of Tc-99m DTPA-GSH in terms of its ability to differentiate tumors from inflammatory lesions. METHODS: DTPA-GSH was synthesized by reaction of GSH with DTPA anhydride under anhydrous conditions in a nitrogen atmosphere. DTPA-GSH was then reacted with Tc-99m sodium pertechnetate in a tin (II) chloride (SnCl2) solution. Gamma camera imaging was performed after intravenous injection of Tc-99m DTPA-GSH into a mouse CT-26 colon cancer model, or a mouse model of inflammation induced by the intramuscular injection of Freund's complete adjuvant. RESULTS: DTPA-GSH was successfully prepared via a straightforward synthetic procedure and radiolabeled with Tc-99m at a high labeling efficiency (>95%). Tc-99m DTPA-GSH was strongly internalized by tumors in colon cancer model mice, with the tumor-to-normal muscle ratio of the complex reaching 4.3±0.9 at 4 h. By contrast, Tc-99m DTPA-GSH showed relatively weak uptake in inflammatory lesions (target-to-non-target ratio=2.0±0.3 at 4 h). A competition study showed that the uptake of Tc-99m DTPA-GSH into tumors was blocked by co-injection with high concentrations of free GSH. CONCLUSIONS: The results of this work indicate that Tc-99m DTPA-GSH is a good candidate for development as a non-invasive tumor imaging agent. Furthermore, Tc-99m DTPA-GSH effectively distinguished between cancerous tissue and inflammatory lesions.

Synovial hemangioma of Hoffa fat pad demonstrated by RBC SPECT/CT.

Synovial hemangioma of Hoffa fat pad is an extremely rare disease, which occurs in the knee joints. Because synovial hemangioma often shows nonspecific symptoms, such as pain, swelling, limping, or limitation of motion, diagnosis could be delayed in many cases. We present a 7-year-old boy referred to our department for Tc red blood cell (RBC) scan for the confirmation of hemangioma suggested by the MRI. RBC scan demonstrated intense radioactivity accumulation in Hoffa pad of right knee joint, and subsequent excision biopsy revealed the mass as venous hemangioma.

Os vesalianum pedis detected with bone SPECT/CT.

We present an 18-year-old man with pain at the lateral aspect of his left foot. Radiograph showed abnormal ossicle in the proximal aspect of the left fifth metatarsal tuberosity, which was articulated with the fifth metatarsal and cuboid bones. Bone scintigraphy and SPECT/CT demonstrated increased uptakes at the ossicles in the proximal aspect of both fifth metatarsal bones. CT revealed that the ossicle and the adjacent bones have well-corticated margins. The diagnosis was os vesalianum, a rare accessory bone of the foot. We have reported the SPECT/CT bone scan findings of the os vesalianum.

Novel Tc-99m labeled ELR-containing 6-mer peptides for tumor imaging in epidermoid carcinoma xenografts model: a pilot study.

OBJECTIVE: ELR-containing peptides targeting CXCR2 could be the excellent candidate for targeting ligand of molecular tumor imaging. In this study, we had developed two ELR-containing 6-mer peptides and evaluated the diagnostic performance of Tc-99m labeled 6-mer peptides as a molecular imaging agent in murine models bearing KB epidermoid carcinoma. METHODS: Peptides were synthesized using Fmoc solid phase peptide synthesis. Radiolabeling efficiency with Tc-99m was evaluated using instant thin-layer chromatography. In KB epidermoid cancer-bearing mice, gamma images had acquired and tumor-to-muscle uptake ratio was calculated. Competition and biodistribution studies had performed. RESULTS: Two 6-mer peptides, ELR-ECG and ECG-ELR were successfully synthesized. After radiolabeling procedures with Tc-99m, the complex Tc-99m ELR-ECG and Tc-99m ECG-ELR were prepared in high yield. In the gamma camera imaging of murine model, Tc-99m ELR-ECG was substantially accumulated in the subcutaneously engrafted tumor and tumor uptake had been suppressed by the free ELR co-injection. However, Tc-99m ECG-ELR was minimally accumulated in the tumor. CONCLUSIONS: Two ELR-containing 6-mer peptides, ELR-ECG and ECG-ELR, were developed as a molecular imaging agent to target CXCR2 of epidermoid carcinoma. Tc-99m ELR-ECG had showed significant uptake in tumor and it was good candidate for a tumor imaging.

Effect of ¹8F-FDG administration on measurements of bone mineral density and body composition by dual-energy X-ray absorptiometry.

The purpose of this study was to determine whether antecedent administration of ¹8F-fluorodeoxyglucose (FDG) used in positron emission tomography (PET) scanning results in corruption of bone mineral density (BMD) and body composition measured by dual-energy X-ray absorptiometry (DXA) system. DXA measurements of BMD and body composition had been performed twice, before and after ¹8F-FDG PET scan in 30 patients. The comparison of pre-values and post-values of all BMD values showed a decrease after the injection. However, only the decrease of whole-body BMD (WB-BMD) was statistically significant (p < 0.05). Whole-body fat mass had increased and whole-body lean body mass had decreased after the injection of ¹8F-FDG, and these were statistically significant (p < 0.05). There is statistically significant correlation between the injected ¹8F-FDG dose and a decrease of WB-BMD (r = -0.405; p < 0.05). The findings of this study suggest that when both ¹8F-FDG PET and DXA measurements for whole-body composition are performed in close-time proximity, ¹8F-FDG PET scans should follow the DXA measurement. Otherwise, BMD measurements of total femur or lumbar spine could be followed by ¹8F-FDG PET in close-time proximity.

Effects of DNA ploidy and S-phase fraction on fluorine-18 FDG uptake of primary breast cancer lesions.

BACKGROUND: Flow cytometry (FCM) evaluating DNA content is emerging as the tool to monitor cell proliferation and malignant potential in several cancers such as stomach, lung, and salivary gland tumor. The purpose of this study was to correlate (18)F-FDG uptake of dual-time-point (DTP) positron emission tomography (PET) imaging with DNA ploidy and S-phase fraction (SPF) in primary breast cancer lesions. PATIENTS AND METHODS: Seventy-two consecutive female patients (mean age ± SD, 52.7 ± 11.1 years; range, 28-81 years) had undergone (18)F-FDG DTP PET/computed tomography (CT) imaging for staging of breast malignancy in our institution during a 5-month period. FCM was performed on fresh-frozen samples of specimens obtained from surgery. (18)F-FDG uptake was then compared with DNA content. RESULTS: Forty-four malignant lesions were included in this study. On FCM, DNA aneuploidy was detected in 14 lesions (31.8%). The maximum standardized uptake values (SUV(max1) and SUV(max2)) (SUV(max1), 6.8 ± 4.6 vs. 3.4 ± 2.4; P = .017), (SUV(max2), 7.9 ± 5.7 vs. 3.6 ± 2.7; P = .015) and retention index (RI) (12.8 ± 11.6 vs. 2.4 ± 10.8; P = .010) were significantly higher in DNA aneuploidy cancer than in DNA diploidy cancer. The value of RI (11.3 ± 11.5 vs. 2.6 ± 11.2; P = .022) was significantly higher in high SPF (> 15%) breast cancer than in low SPF (≤ 15%) breast cancer. CONCLUSIONS: High (18)F-FDG uptake in breast cancer might be an indicator of DNA aneuploidy and high SPF. We propose that (18)F-FDG PET/CT imaging may be a noninvasive and useful tool for predicting the DNA content in breast cancer.

Abdominal aortic aneurysm with bony erosion mimicking recurrent non-Hodgkin lymphoma on FDG PET/CT.

An 80-year-old man with a history of non-Hodgkin lymphoma in complete remission after chemotherapy in 2009 presented with lumbar pain. MRI demonstrated anterior L4 bony erosions. FDG PET/CT revealed the large retroperitoneal mass with central photopenia and a mildly hypermetabolic rim. Ultrasound revealed a dilated aorta with atherosclerotic plaque and eccentric mural thrombus. A newly developed mass-like lesion in a patient with history of lymphoma could be mistaken for lymphoma recurrence on FDG PET/CT.