Homodimeric peptide radiotracer [68Ga]Ga-NOTA-(TMVP1)2 for VEGFR-3 imaging of cervical cancer patients.

PURPOSE: Vascular endothelial growth factor receptor 3 (VEGFR-3) plays a critical role in tumor lymphangiogenesis and metastasis, holding promise as a promising therapeutic target for solid tumors. TMVP1 (LARGR) is a 5-amino acid peptide previously identified in our laboratory from bacterial peptide display system that specifically targets VEGFR-3. Radiolabeled TMVP1 can be used for non-invasive imaging of VEGFR-3 expressing tumors. Homodimeric peptides have better targeting ability than monomeric peptides, and it is worth exploring whether homodimers of TMVP1 ((TMVP1)2) can achieve better imaging effects. This study aimed to explore the peptide properties and tumor assessment value of [68Ga]Ga-labeled (TMVP1)2. METHODS: In this study, we developed a TMVP1 homodimer that was conjugated with 1,4,7-triazacyclononane-N, N', N″-triacetic acid (NOTA) via tetraethyleneglycol (PEG4) and triglyicine (Gly3) spacer, and labeled with 68Ga, to construct [68Ga]Ga-NOTA-(TMVP1)2. Binding of VEGFR-3 by TMVP1 and (TMVP1)2, respectively, was modeled by molecular docking. The affinity of [68Ga]Ga-NOTA-(TMVP1)2 for VEGFR-3 and its ability to bind to cells were evaluated. MicroPET imaging and biodistribution studies of [68Ga]Ga-NOTA-(TMVP1)2 were performed in subcutaneous C33A cervical cancer xenografts. Five healthy volunteers and eight patients with cervical cancer underwent whole-body PET/CT acquisition 30-45 min after intravenous injection of [68Ga]Ga-NOTA-(TMVP1)2. RESULTS: Both molecular docking and cellular experiments showed that homodimeric TMVP1 had a higher affinity for VEGFR-3 than monomeric TMVP1. [68Ga]Ga-NOTA-(TMVP1)2 was excreted mainly through the renal route and partly through the liver route. In mice bearing C33A xenografts, [68Ga]Ga-NOTA-(TMVP1)2 specifically localized in the tumor (2.32 ± 0.10% ID/g). Pretreatment of C33A xenograft mice with the unlabeled peptide NOTA-(TMVP1)2 reduced the enrichment of [68Ga]Ga-NOTA-(TMVP1)2 in tumors (0.58 ± 0.01% ID/g). [68Ga]Ga-NOTA-(TMVP1)2 proved to be safe in all healthy volunteers and recruited patients, with no side effects or allergies noted. In cervical cancer patients, a majority of the [18F]-FDG identified lesions (18/22, 81.8%) showed moderate to high signal intensity on [68Ga]Ga-NOTA-(TMVP1)2. SUVmax and SUVmean were 2.32 ± 0.77 and 1.61 ± 0.48, respectively. With normal muscle (gluteus maximus) as background, tumor-to-background ratios were 3.49 ± 1.32 and 3.95 ± 1.64 based on SUVmax and SUVmean, respectively. CONCLUSION: The favorable characterizations of [68Ga]Ga-NOTA-(TMVP1)2 such as convenient synthesis, high specific activity, and high tumor uptake enable the evaluation of VEGFR-3 in cervical cancer patients and warrant further clinical studies. TRIAL REGISTRATION: ChiCTR-DOD-17012458. Registered August 23, 2017 (retrospectively registered).

Constructing triazole-modified quinazoline derivatives as selective c-MYC G-quadruplex ligands and potent anticancer agents through click chemistry.

c-MYC is a hallmark of various cancers, playing a critical role in promoting tumorigenesis. The formation of G-quadruplex (G4) in the c-MYC promoter region significantly suppresses its expression. Therefore, developing small-molecule ligands to stabilize c-MYC G4 formation and subsequentially suppress c-MYC expression is an attractive topic for c-MYC-driven cancer therapy. However, achieving selective ligands for c-MYC G4 poses challenges. In this study, we developed a series of triazole-modified quinazoline (TMQ) derivatives as potential c-MYC G4 ligands and c-MYC transcription inhibitors from 4-anilinoquinazoline lead 7a using click chemistry. Importantly, the c-MYC G4 stabilizing ability and antiproliferation activity were well correlated among these new derivatives, particularly in the c-MYC highly expressed colorectal cancer cell line HCT116. Among them, compound A6 exhibited good selectivity in stabilizing c-MYC G4 and in suppressing c-MYC transcription better than 7a. This compound induced G4 formation, selectively inhibited G4-related c-MYC transcription and suppressed the progression of HCT116 cells. These findings identify a new c-MYC transcription inhibitor and provide new insights for optimizing c-MYC G4-targeting ligands.

Performance of 68Ga-labeled prostate-specific membrane antigen ligand positron emission tomography/computed tomography in the diagnosis of primary prostate cancer: a systematic review and meta-analysis.

OBJECTIVE: To explore the feasibility of 68Ga-PSMA PET/CT in diagnosing primary prostate cancer. MATERIALS AND METHODS: Embase, PubMed and Cochrane Library databases were searched for studies published before July 2020. The studies that used 68Ga-PSMA PET/CT for detecting primary prostate cancer, and pathological biopsy as the reference standard were included. The selecting process used preferred reporting items for systematic reviews and meta-analyses (PRISMA). The quality of enrolled studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. RESULTS: According to our search strategy, 9 studies were included for analysis. A total of 547 patients with primary prostate cancer and 443 lesion segments that underwent 68Ga-PSMA PET/CT scans were included and their pathological biopsies were compared. The results of these studies showed some differences. For instance, the lowest sensitivity of 68Ga-PSMA PET/CT in diagnosing primary prostate cancer was 67%, while the highest sensitivity recorded was 97%. CONCLUSIONS: Compared with conventional imaging examinations, 68Ga-PSMA PET/CT had higher sensitivity and specificity in detecting primary prostate cancer. At present, most of the studies that used 68Ga-PSMA PET/CT for detecting prostate cancer are retrospective studies. Based on its advantage of high detection rate, the use of 68Ga-PSMA PET/CT in the detection of primary prostate cancer is worthy of promotion.

Indirect comparison of the diagnostic performance of 18F-FDG PET/CT and MRI in differentiating benign and malignant ovarian or adnexal tumors: a systematic review and meta-analysis.

OBJECTIVE: To compare the value of fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) and magnetic resonance imaging (MRI) in differentiating benign and malignant ovarian or adnexal tumors. MATERIALS AND METHODS: English articles reporting on the diagnostic performance of MRI or 18F-FDG PET/CT in identifying benign and malignant ovarian or adnexal tumors published in PubMed and Embase between January 2000 and January 2021 were included in the meta-analysis. Two authors independently extracted the data. If the data presented in the study report could be used to construct a 2 × 2 contingency table comparing 18F-FDG PET/CT and MRI, the studies were selected for the analysis. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was used to evaluate the quality of the included studies. Forest plots were generated according to the sensitivity and specificity of 18F-FDG PET/CT and MRI. RESULTS: A total of 27 articles, including 1118F-FDG PET/CT studies and 17 MRI studies on the differentiation of benign and malignant ovarian or adnexal tumors, were included in this meta-analysis. The pooled sensitivity and specificity for 18F-FDG PET/CT in differentiating benign and malignant ovarian or adnexal tumors were 0.94 (95% CI, 0.87-0.97) and 0.86 (95% CI, 0.79-0.91), respectively, and the pooled sensitivity and specificity for MRI were 0.92 (95% CI: 0.89-0.95) and 0.85 (95% CI: 0.79-0.89), respectively. CONCLUSION: While MRI and 18F-FDG PET/CT both showed to have high and similar diagnostic performance in the differential diagnosis of benign and malignant ovarian or adnexal tumors, MRI, a promising non-radiation imaging technology, may be a more suitable choice for patients with ovarian or accessory tumors. Nonetheless, prospective studies directly comparing MRI and 18F-FDG PET/CT diagnostic performance in the differentiation of benign and malignant ovarian or adnexal tumors are needed.

A novel humanized anti-tumor necrosis factor-related apoptosis-inducing ligand-R2 monoclonal antibody induces apoptotic and autophagic cell death.

It is well known that the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/TNFSF10) is specifically expressed in various tumor cells, but less or no expression in most normal tissues and cells. While TRAIL engages with its native death receptors, TRAIL receptor 1 (TRAIL-R1) or 2 (TRAIL-R2), usually elicits the tumor cell death by apoptosis. In this study, we report that a novel humanized monoclonal antibody against TRAIL-R2 (named as zaptuzumab) well remain the biological activity of the parental mouse antibody AD5-10 inducing cell death in various cancer cells, but little effect on normal cells. Zaptuzumab also markedly inhibited the tumor growth in the mouse xenograft of NCI-H460 without toxicity to the liver and kidney, and the efficacy of tumor suppression was increased significantly while it combined with cis-dichlorodiamineplatinum. Especially, 131 I-labeled zaptuzumab injected into mouse tail vein specifically targeted to the xenograft of the lung cancer cells. Confocal analysis showed that zaptuzumab bound with TRAIL-R2 on cell surface could be quickly internalized and transferred into the lysosome. Furthermore, zaptuzumab possessed a high level of antibody-dependent cytotoxicity as well as complement-dependent cytotoxicity. Study on the mechanisms of cell death induced by zaptuzumab showed that it efficiently induced both caspase-dependent apoptosis and autophagic cell death. These data suggest that the humanized anti-TRAIL-R2 monoclonal antibody or the second generation of the antibody may have an important clinical usage for cancer immunotherapy. © 2017 IUBMB Life, 69(9):735-744, 2017.

Imaging Potential and Biodistribution in vivo of 2-[18F]Fluoropropionic Acid in Breast Cancer-bearing Mice.

OBJECTIVE: To investigate the imaging potential and biodistribution in vivo of a novel positron imaging agent,2-[(18)F]fluoropropionic,in breast cancer-bearing mice. Methods: 2-[(18)F]fluoropropionic acid (7.4-11.1 MBq)was injected into the breast cancer-bearing mice via tail vein,followed by micro positron emission tomography at 60 min and 120 min.The radioactivity per volume (Bq/ml) in organs was transferred to percentage injected dose per gram(% ID/g)by Inveon Research software and the biodistribution of 2-[(18)F]fluoropropionic acid in organs was deduce.The same operations were done with (18)F-FDG. RESULTS: 2-[(18)F]fluoropropionic acid was mainly distributed in the urinary bladder,intestine,and liver between 60 min to 120 min.The breast cancer at right flank was visualized clearly,and the radioactivity uptake was (13.74±1.97)% ID/g and (14.84±1.06)% ID/g,respectively,at these two time points (P=0.454).The radioactivity uptakes in muscle and brown tissue were relatively low.The radioactivity uptake of (18)F-FDG was (10.27±2.34)% ID/g at the breast cancer 60 min after injection,and radioactivity uptake of the brown fat on the back was obvious. CONCLUSIONS: Positron imaging agent 2-[(18)F]fluoropropionic acid can be used to image breast cancer.It may be applied in the noninvasive imaging of breast cancer in clinical settings.

Cholesterol-conjugated let-7a mimics: antitumor efficacy on hepatocellular carcinoma in vitro and in a preclinical orthotopic xenograft model of systemic therapy.

BACKGROUND: A major challenge to the clinical utility of let-7 for hepatocellular carcinoma (HCC) therapy is the lack of an effective carrier to target tumours. We confirmed the high transfection efficiency of cholesterol-conjugated let-7a miRNA mimics (Chol-let-7a) in human HCC cells, as well as their high affinity for liver tissue in nude mice. However, their antitumor efficacy via systemic delivery remains unknown. METHODS: We explored the effects of Chol-let-7a on HCC in vitro and in vivo. Cell viability and mobility, let-7a abundance and the target ras genes was measured. Live-cell image and cell ultrastructure was observed. Antitumor efficacy in vivo was analyzed by ultrasonography, hispatholgogy and transmission electronic microscopy in a preclinical model of HCC orthotopic xenografts with systemic therapy. RESULTS: Chol-let-7a inhibited the viability and mobility of HCC cells. Chol-let-7a was primarily observed in the cytoplasm and induced organelle changes, including autophagy. Mild changes were observed in the cells treated with negative control miRNA. Chol-let-7a reached HCC orthotopic tumours, significantly inhibited tumour growth, and prevented local invasion and metastasis. Compared to control tumours, Chol-let-7a-treated tumours showed more necrosis. Tumour cells showed no significant atypia, and mitoses were very rare after systemic Chol-let-7a therapy. Furthermore, let-7a abundance in orthotopic xenografts was coincident with a reduction in the expression of 3 human ras mRNAs and RAS proteins. CONCLUSIONS: Chol-let-7a exerted significant antitumor effects by down-regulating all human ras genes at the transcriptional and translational levels. Chol-let-7a inhibited cell proliferation, growth, and metastasis, and mainly functioned in the cytoplasm. Chol-let-7a represents a potential useful modified molecule for systemic HCC therapy.

18F-FDG PET/CT revealed sporadic schwannomatosis involving the lumbar spinal canal and both lower limbs: a case report.

Schwannomatosis is a rare autosomal dominant hereditary syndrome disease characterized by multiple schwannomas throughout the body, without bilateral vestibular schwannoma or dermal schwannoma. The most common location of schwannomatosis is the head and neck, as well as the limbs, while multiple schwannomas in the lumbosacral canal and lower extremities are relatively rare. In this study, we report a 79-year-old woman diagnosed with schwannomatosis. MRI and contrast-enhanced imaging revealed multiple schwannomas in both lower extremities. An 18F-FDG PET/CT examination revealed that in addition to multiple tumors with increased 18F-FDG uptake in both lower extremities, there was also an increased 18F-FDG uptake in a mass in the lumbosacral canal. These masses were confirmed to be schwannomas by pathology after surgery or biopsy. 18F-FDG PET/CT findings of schwannomas were correlated with MRI and pathological components. Antoni A area rich in tumor cells showed significant enhancement on contrast-enhanced T1WI, and PET/CT showed increased uptake of 18F-FDG in the corresponding area, while Antoni B region rich in mucus showed low enhancement on contrast-enhanced T1WI, accompanied by a mildly increased 18F-FDG uptake.

18F-FDG PET/CT features of Meigs syndrome induced by ovarian sex cord stromal tumors: a retrospective clinical study.

The objective of this study was retrospectively to analyze the clinical characteristics and 18F-FDG PET/CT findings in Meigs syndrome (MS) patients. A total of 21 patients with MS induced by ovarian stromal tumors and 69 patients with pseudo-MS caused by ovarian cancer (OC-PMS) were subjected to evaluation using 18F-FDG PET/CT. Visual and semi-quantitative methods were employed to analyze the PET/CT findings. Visual analysis included recording whether the density of the primary tumor was uniform, whether there were cystic changes and calcifications, and the location of serous fluid accumulation. Semi-quantitative analysis involved the measurement of the tumor size, SUVmax, and SUVmean. No significant difference was observed in the size and density of primary tumors between the MS group and the OC-PMS group. However, the SUVmax and SUVmean of tumors in the MS group were found to be significantly lower than those in the OC-PMS group. The amount of serous cavity effusion caused by ovarian sex cord stromal tumors was found to be unrelated to the size of the tumor, SUVmax, and SUVmean but was positively correlated with the level of Ca125. MS patients have both benign ovarian tumors and ascites and/or pleural effusion, which may be accompanied by elevated Ca125 levels. This should be considered as one of the differential diagnoses for ovarian cancer. Understanding the PET/CT features of MS can facilitate the attainment of an accurate diagnosis before surgery.

CT, MRI, and PET/CT imaging features of thoracic spine epithelioid hemangioma: a retrospective observational study.

Introduction: Epithelioid hemangioma (EH) is an intermediate locally aggressive tumor that consists of epithelioid cells and endothelial cell differentiation, which can occur at any age, but is most common between the ages of 30 and 40 years. EH in the thoracic spine is rare, and accurate diagnosis is critical to treatment planning. Our aim was to explore the imaging and clinical data of thoracic spine EH to improve the understanding of this rare disease. Methods: From January 1, 2018 to June 30, 2023, a database of thoracic spine masses was retrospectively reviewed. Five patients with histologically proven thoracic spine EH and complete imaging available were identified and analyzed. Computed tomography (CT) and magnetic resonance imaging (MRI) findings were evaluated separately by two radiologists with more than 10 years of experience. Positron emission tomography (PET)/CT was conducted by two nuclear medicine diagnostic technologists with at least 5 years of experience. Results: The patients included three male and two female patients aged 23 to 56 years (mean age was 38.4 ± 14.3 years). All patients underwent CT, MRI, and 18F-FDG PET/CT examination before treatment. Four patients were limited to one vertebral involvement, only one patient had multiple vertebral involvement, and all tumors involved the accessories, including one involving the posterior ribs. The maximum diameter of the tumor ranged from 2.7 to 4.3. Conclusions: CT, MRI, and 18F-FDG PET/CT findings of thoracic spine EH have certain characteristics, and understanding these imaging findings will help to obtain accurate diagnosis before surgery.

Multimodal imaging findings of primary liver clear cell carcinoma: a case presentation.

Primary clear cell carcinoma of liver (PCCCL) is a special and relatively rare subtype of hepatocellular carcinoma (HCC), which is more common in people over 50 years of age, with a preference for men and a history of hepatitis B or C and/or cirrhosis. Herein, we present a case of a 60-year-old woman who came to our hospital for medical help with right upper abdominal pain. The imaging examination showed a low-density mass in the right lobe of his liver. In contrast enhanced computed tomography (CT) or T1-weighted imaging, significant enhancement can appear around the tumor during the arterial phase, and over time, the degree of enhancement of the tumor gradually decreases. The lession showed obviously increased fluorine-18 fluorodeoxyglucose (18F-FDG) uptake on positron emission tomography/CT. These imaging findings contribute to the diagnosis of PCCCL and differentiate it from other types of liver tumors.

A Case of Nasal Extranodal NK/T-cell Lymphoma of Lower Limb Muscle Revealed by 18F-FDG PET/CT.

BACKGROUND: Extranodal NK/T-cell lymphoma (ENKTCL) is a type of malignant non-Hodgkin's lymphoma originating from mature T cells and NK cells, mainly involving the upper aerodigestive tract, including the nasal cavity, nasopharynx, oropharynx, oral cavity, hypopharynx, larynx, and occasionally the skin, salivary glands, testes, and gastrointestinal tract, but rarely the skeletal muscle. CASE PRESENTATION: An 82-year-old man presented with redness, swelling, and pain in his right lower limb for 3 months. He was initially diagnosed with cellulitis at another hospital and was treated conservatively for two weeks without improvement. He underwent a biopsy of the lesioned muscle and histopathology revealed nasal type ENKTCL. 18F-FDG PET/CT was recommended for the staging of the lymphoma, and the results showed that except for the muscles of the right lower extremity, no other organs and tissues were involved. CONCLUSION: ENKTCL confined to the muscle of the lower extremity is rare and often initially misdiagnosed as myositis because of red, swollen, heat, and painful symptoms that resemble inflammation, and in it, higher radiotracer uptake in 18F-FDG PET/CT helps to distinguish it from myositis.

A large gastric splenosis mimicking gastrointestinal stromal tumor: A case report and literature review.

Splenosis pertains to the phenomenon wherein a segment of the spleen undergoes detachment and becomes embedded in other anatomical regions subsequent to traumatic rupture or therapeutic resection, and then progressively establishing blood circulation to foster the regeneration of splenic tissue. Existing literature posits that splenosis predominantly manifests within the confines of the abdominal and pelvic cavities. The objective of the current study was to present an uncommon case involving the occurrence of splenosis within the gastric myometrium, thereby contributing to the current knowledge regarding splenosis. A 16-year-old female sought medical assistance owing to recurrent abdominal pain persisting for a duration of six months, and had a history of splenectomy two years prior. Gastroscopy, endoscopic ultrasound and computed tomography (CT) examination collectively identified a lesion in the submucosal prominence of the fundus of the stomach. Initial considerations based on imaging examinations leaned towards a gastrointestinal stromal tumor. Consequently, an endoscopic resection was undertaken. Remarkably, the pathological findings and histochemistry concurred with the alterations associated with ectopic spleen implantation, leading to a stable postoperative course. In conclusion, splenosis denotes the implantation of a segment of the spleen into extraneous anatomical sites, attributable to traumatic rupture or therapeutic resection. The preoperative diagnosis of splenosis can pose a challenge, potentially culminating in unnecessary radical clinical interventions. Therefore, the acquisition of a comprehensive medical history, with a particular focus on surgical and trauma events, emerges as pivotal for an accurate diagnosis. In light of novel diagnostic modalities, the non-invasive technology of nuclear medicine can efficaciously visualize ectopic splenic tissue, thereby averting superfluous surgical procedures. It is both feasible and imperative to implement individualized treatment strategies for patients afflicted with splenosis.

[Expression and affinity purification of recombinant human epidermal growth factor receptor-2 affibody with C-terminal cystein].

OBJECTIVE: To prepare the modified ZHER2V2 affibody with amino-terminal HEHEHE sequence and carboxyl-terminal GGGC sequence by gene recombinant expression,which is the basis for invasive HER2 imaging with affibody. METHODS: The encoded affibody gene was optimized by codon preference of E. coli with gene designer software. The N-terminal of affibody was fused with HEHEHE sequence,while the C-terminal was fused with GGGC sequence. The synthetic gene was confirmed by Hind 3 endonuclease restriction and gene sequencing. The human epidermal growth factor receptor-2(HER2)affibody gene was sub-cloned into pET22b(+)plasmid and transformed into competent BL21(DE3)bacteria. The expression of modified affibody was induced with isopropyl Β-D-1-thiogalactopyranoside(IPTG)and identified by SDS-PAGE. The affibody was purified by nickel affinity binding and imidazole elution. The purified affibody was labeled with (68)Ga and its affinity was determined by saturation analysis with HER2-positive cells MDA-MB-361. RESULTS: The affibody gene containing N-terminal HEHEHE and C-terminal GGGC sequences were confirmed by Hind 3 endonuclease restriction and gene sequencing. A newly expressed 8×10(3) protein was expressed from the induced recombinant bacteria identified by SDS-PAGE after sub-cloning HER2 affibody gene into pET22b(+)plasmid,transforming recombinant plasmid into competent BL21(DE3)bacteria and inducing the recombinant bacteria with IPTG. The expressed protein was purified from nickel agarose by 60 mmol/L imidazole eluting. The affinity Kd value of (68)Ga labeled affibody to HER2 positive MDA-MB-361 cells was 1.5 nmol/L. CONCLUSION: The affiibody ZHER2V2 containing N-terminal HEHEHE and C-terminal GGGC was successfully prepared by gene optimization,recombinant expression and affinity purification.

Diagnosis and management of extramedullary plasmacytoma in nasal cavity: Clinical experience and literature review.

Nasal extramedullary plasmacytoma (EMP) is a rare plasma cell tumor that occurs in the soft tissue of the nasal cavity, and its imaging characteristics are still unclear. The purpose of this study was to investigate the clinical features, imaging findings, treatment, survival analysis, and prognosis of nasal EMP, and to provide a systematic review of the patients we treated and the published literature. A 45-year-old female patient who presented with epistaxis with nasal obstruction was recommended for magnetic resonance imaging to assess the nature of the lesion. On magnetic resonance imaging, abnormal signal shadow can be seen in the right nasal cavity. Diffusion weighted imaging showed signal of the lesion was significantly limited, presenting high signal, with a low apparent dispersion coefficient, and the lesion was significantly enhanced on contrast-enhanced scan. Combined with the clinical manifestations of the patient, who was initially considered to have a hemangioma. She underwent endoscopic nasal surgery under general anesthesia to remove the mass, and the final pathology confirmed it was EMP. However, the final pathology confirmed EMP. Five months later, the patient came to our hospital for follow-up and underwent fluorine-18-fluorodeoxyglucose/positron emission tomography/computed tomography scan, which showed no recurrence of the lesion and no transformation of multiple myeloma. The nasal EMP imaging findings were mostly soft tissue masses with uniform density or signal, which were significantly enhanced by enhancement scan, high signal on diffusion weighted imaging and low signal on apparent dispersion coefficient. Immunohistochemical staining for CD38, CD138, and CD79a was positive in most of the cases evaluated, while CD20 and CD10 were negative. The absence of dilated features, infiltrative features and the presence of significant contrast enhancement may be relatively specific imaging findings of nasal EMP. The prognosis of nasal EMP is good, and recurrence, metastasis, and transformation into multiple myeloma are rare. Because the lesions are sensitive to radiotherapy, surgical resection combined with radiotherapy is a more effective treatment.

Radiosynthesis, optimization and pharmacokinetic study of the 99m Tc-labeled human epidermal growth factor receptor 2 affibody molecule probe 99m Tc-(HE) 3 Z HER2:V2.

OBJECTIVE: To prepare a single-photon molecular probe easily labeled with 99m Tc for evaluating the expression status of the human epidermal growth factor receptor 2 (HER2) receptor in ovarian cancer. MATERIALS AND METHODS: The HEHEHE tag was added to the amino terminus of the affibody Z HER2:V2 by the method of gene recombinant expression, and a new affibody was synthesized which was easy to be labeled with 99m Tc. The newly prepared affibody was labeled with 99m Tc, and pharmacokinetic studies were carried out. RESULTS: A new affibody (HE) 3 Z HER2:V2 was prepared by the method of gene recombination and expression, which is easy to be labeled with 99m Tc. The 99m Tc labeling of the affibody can reach about 95% at 90°C. The pharmacokinetic study has shown that the 99m Tc-labeled molecular probe has a fast clearance time in the blood and little side effect, which may be a promising single-photon emission computed tomography (SPECT) imaging agent. CONCLUSION: The affibody (HE) 3 Z HER2:V2 is easy to be labeled with 99m Tc, has a high yield and has a suitable half-life in vivo, which is suitable for the next step in ovarian cancer model imaging research.

Comparison of the application of 18F-FDG and 68Ga-DOTATATE PET/CT in neuroendocrine tumors: A retrospective study.

The present study aimed to compare the efficacy of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT imaging in the diagnosis, staging, and prognosis evaluation of neuroendocrine tumors (NET). A total of 55 patients (43 were initially evaluated, 12 were evaluated after treatment) who underwent fluorine-18 labeled fluorodeoxyglucose (18F-FDG) and 68Ga DOTATE PET/CT examinations were reviewed retrospectively, and the pathological data were collected. In the initial evaluation, 27/43 were pathologically confirmed as NET patients, as detected by gallium-68 labeld 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraaceticacid-D-Phel-Tyr3-Thr8-OC; among them, 23 were correctly detected by 18F-FDG. In lesion-based comparison, 119/168 focal lesions were depicted on 18F-FDG PET/CT and 68Ga-DOTATATE PET/CT, respectively (P = .0363). Strikingly, gallium-68 labeld 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraaceticacid-D-Phel-Tyr3-Thr8-OC had higher maximum standard uptake value than 18F-FDG but was negatively related to the NET grade for the former, while the latter was positively related to the NET. The value of 68Ga-DOTATATE PET/CT in the diagnosis and staging of NET is higher than that of 18F-FDG PET/CT in NETs, while the value of 18F-FDG PET/CT cannot be ignored in the NET. The combined application of the 2 tracers has major clinical significance in the management of patients with NET.

Metanephric adenoma in children: A case report and literature review.

Metanephric adenoma (MA) is a rare type of benign renal epithelial tumor that can develop at any age. Nonetheless, MA is extremely rare in children and only a few cases have been reported to date. The present study aimed to report the case of a 5-year-old female found to have a mass in the right kidney during a routine pre-enrollment physical examination. Computed tomography (CT) images revealed multiple high-density calcifications in the mass, and contrast-enhanced CT and magnetic resonance imaging demonstrated that the mass was significantly enhanced in the cortical phase and decreased in the medullary phase. Based on these findings, the mass was initially diagnosed as angiomyolipoma before surgery; however, postoperative pathology confirmed the mass to be a MA. MAs are typically a type of soft tissue mass with relatively uniform density or signal, showing delayed enhancement in contrast-enhanced scanning. However, the mass found in the present study presented diffused high-density calcification, which was obvious in the early phase of contrast-enhanced scanning but weakened in the delayed enhancement phase. In conclusion, the present case study demonstrated that MA should be considered as one of the imaging differential diagnoses of fat-poor angiomyolipoma, renal carcinoma and oncocytoma.

Fluoro-18-fluorodeoxyglucose positron emission tomography/computed tomography detects Ewing's sarcoma of the larynx with multiple distant bone metastases: a case report and literature review.

Ewing sarcomas (EWS) are highly malignant neoplasms of mesenchymal origin that are rare in the head and neck. Only a few laryngeal EWS have been reported in the literature. We report a 47 years-old man who visited our hospital for medical help after 5 months of hoarseness and sore throat. Computed tomography (CT) showed uneven thickening of the epiglottis fold, right vocal cord, and anterior union. In addition, fluoro-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET)/CT has confirmed high activity in the already known laryngeal and nodal lesions, and has revealed otherwise unknown skeletal metastases. We also reviewed the published clinical features, histopathology, and imaging findings of nine patients with laryngeal EWS confirmed by pathology. The main clinical manifestations of laryngeal EWS are rapidly growing lumps, hoarseness, acute respiratory distress, and aphonia. The EWS tumor cells usually express CD99, vimentin, synaptophysin (Syn), and neuron-specific enolase (NSE) but do not express common antigen (LCA), CD20, and chromaffin granin (CgA). Laryngeal EWS' CT imaging characteristics are mainly homogeneous, well-bounded soft-tissue masses. Our case suggests that EWS should be considered a differential diagnosis of laryngeal cancer, especially when PET/CT reveals distant bone metastasis, which is more likely to indicate EWS.

Extramedullary Plasmacytoma of Nasal Cavity: A Case Report and Literature Review.

Extramedullary plasmacytoma (EMP) is a tumor characterized by plasma cell proliferation in organs or tissues outside the bone marrow. It originates from B lymphocytes and can occur in all extramedullary tissues and organs of the body. Primary EMPs of the nasal cavity are relatively rare and mostly presented as case reports. Nasal EMP usually manifests as nasal obstruction, epistaxis, and progressive dyspnea. A 64-year-old man was admitted to our hospital because of rhinorrhagia with nasal obstruction. Computed tomography (CT) revealed a mass in the right nasal passage, which we resected under nasal endoscopy. At the 2-year follow-up, positron emission tomography/CT showed osteolytic bone destruction in the third cervical vertebra and its accessories, accompanied by increased metabolism. We considered the possibility of progression to myeloma, but the patient refused another puncture biopsy. We reviewed the literature for the clinical characteristics and CT findings of 14 patients pathologically confirmed with EMPs of the nasal cavity. All patients had nonspecific clinical manifestations, such as nasal obstruction and epistaxis. Computed tomography mostly showed a uniform-density polypoid mass in the nasal cavity. Therefore, nasal EMP should be included in the differential diagnosis of nasal polyps and other nasal tumors.