Al18F-NOTA-Octreotide outperforms 18F-FDG in identifying rare renal metastases from pancreatic neuroendocrine tumor.

We presented a case involving a 56-year-old man who had been experiencing shoulder and back pain for over a year, with extensive bone metastases revealed by a bone scan. To identify the primary source of these issues, the patients underwent a fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) scan, which indicated moderate uptake in the right renal soft mass and low uptake in multiple osteolytic lesions. Pathological examination and immunohistochemical staining of the renal mass supported the diagnosis of neuroendocrine tumors. Subsequently, a novel somatostatin receptor imaging agent, Al18F-NOTA-octreotide (18F-OC), was performed to further investigate the source of metastatic lesions and to stage the tumor. The 18F-OC scan revealed a high-uptake lesion in the pancreatic head, as well as additional lymph node and bone metastases lesions.Compared to 18F-FDG, the 18F-OC demonstrated superior imaging capabilities and a significantly higher tumor-to-background ratio in neuroendocrine neoplasms, which contributed to improvingthe staging and treatment management.

Lipophilic Group-Modified Manganese(II)-Based Contrast Agents for Vascular and Hepatobiliary Magnetic Resonance Imaging.

Effective vascular and hepatic enhancement and better safety are the key drivers for exploring gadolinium-free hepatobiliary contrast agents. Herein, a facile strategy proposes that the high lipophilicity may be favorable to enhancing sequentially vascular and hepatobiliary signal intensity based on the structure-activity relationship that both hepatic uptake and interaction with serum albumins partly depend on lipophilicity. Therefore, 11 newly synthesized derivatives of manganese o-phenylenediamine-N,N,N',N'-tetraacetic acid (MnLs) were evaluated as vascular and hepatobiliary agents. The maximum signal intensities of the heart, liver, and kidneys were strongly correlated with log P, a key indicator of lipophilicity. The most lipophilic agent, MnL6, showed favorable relaxivity when binding with serum albumin, good vascular enhancement, rapid excretion, and reliable hepatobiliary phases comparable to a classic hepatobiliary agent, gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) for in vivo liver tumor imaging. Inhibition experiments confirmed the hepatic targeting of MnL6 is mediated by organic anion-transporting polypeptides.

Predictive value of Dmax and %ΔSUVmax of 18F-FDG PET/CT for the prognosis of patients with diffuse large B-cell lymphoma.

PURPOSE: To investigate the prognosis value of a combined model based on 18F-fluoro-deoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT) baseline and interim parameters in patients with diffuse large B-cell lymphoma (DLBCL). METHODS: We retrospectively analyzed the PET metabolic parameters and clinical data of 154 DLBCL patients between December 2015 and October 2020. All of these patients underwent 18F-FDG PET/CT scan before treatment and after three or four courses of chemotherapy. The optimal cut-off values for quantitative variables were determined by the receiver operating characteristic (ROC) curve. The baseline and interim PET/CT parameters, which respectively included maximum standardized uptake value (SUVmax0), total metabolic tumor volume (TMTV0), standardized total metabolic tumor volume (STMTV0), and the distance between the two furthest lesions (Dmax) and total tumor lesion glycolysis (TTLG1), SUVmax1, TMTV1, and the rate of change of SUVmax (%ΔSUVmax), and clinical characteristics were analyzed by chi-squared test, Kaplan-Meier survival curve, and Cox regression analysis. RESULTS: Of 154 patients, 35 exhibited disease progression or recurrence. ROC analysis revealed that baseline 18F-FDG PET/CT metabolic parameters, including maximum standardized uptake value (SUVmax0), total metabolic tumor volume (TMTV0), standardized total metabolic tumor volume (STMTV0), and the distance between the two furthest lesions (Dmax), along with interim 18F-FDG PET/CT metabolic parameters such as total tumor lesion glycolysis (TTLG1), SUVmax1, TMTV1, and the rate of change of SUVmax (%ΔSUVmax), were predictive of relapse or progression in DLBCL patients (P < 0.05). The chi-squared test showed that TMTV0, STMTV0, Dmax, SUVmax1, TMTV1, TTLG1, %ΔSUVmax, Deauville score, IPI, Ann Arbor stage, and LDH were associated with patient prognosis (P < 0.05). Multivariate Cox regression analysis showed that Dmax (P = 0.021) and %ΔSUVmax (P = 0.030) were independent predictors of prognosis in DLBCL patients. There were statistically significant differences in PFS among the three groups with high, intermediate, and low risk according to the combination model (P < 0.001). The combination model presented higher predictive efficacy than single indicators. CONCLUSION: The combined model of baseline parameter Dmax and intermediate parameter %ΔSUVmax of 18F-FDG PET/CT improved the predictive efficacy of PFS and contributed to the risk stratification of patients, providing a reference for clinical individualization and precision treatment.

Case Report: a rare primary gastric choriocarcinoma revealed on 18F-FDG PET/CT.

Choriocarcinoma is an exceptionally aggressive trophoblastic cell tumor that that typically originates in gonadal tissues, with rare occurrences outside the gonads, including the mediastinum, retroperitoneum, and intracranial sites. However, it rarely occurs in the stomach. Herein, we presented a case of primary gastric choriocarcinoma in a 27-year-old female patient who found multiple liver masses detected during physical examination, accompanied by remarkably elevated human chorionic gonadotropin levels. The 18F-FDG PET/CT scan suggested ring-shaped intense uptake masses located in the gastric sinus and liver, and no significance in the pelvic region. Final histopathology indicated primary choriocarcinoma of the stomach. This case illustrates that 18F-FDG PET/CT is an essential imaging technique for the clinical diagnosis and stage of primary choriocarcinoma.

An exploratory study of unexplained concentration of 18F-PSMA-1007 in the bladder for prostate cancer PET/CT imaging.

18F-PSMA-1007 PET/CT imaging is increasingly used for the diagnosis, staging, and efficacy assessment of patients with prostate cancer. Compared with other PSMA tracers, 18F-PSMA-1007 is mainly cleared by the liver and bile and has lower urinary clearance, thus allowing a better assessment of the lesions around the bladder. However, there were some patients who showed an obvious concentration of the 18F-PSMA-1007 in the bladder, which may affect the observation of peripheral lesions, but the mechanism of this change is unknown. The aim of this study was to explore the cause of bladder 18F-PSMA-1007 concentration by assessing the clinical and imaging characteristics of 18F-PSMA-1007 PET/CT scans. A total of 284 patients were included in this retrospective study, and their clinical characteristics such as age, height, weight, Gleason score, metastases, different treatment methods, the level of liver and kidney function, PSA level, and imaging characteristics such as 18F-PSMA-1007 injected activity, the interval between injection to scan, physiological distribution (parotid gland, kidney, liver, spleen, intestine, obturator internus), pathological distribution (prostate lesions, metastases) were collected, and were compared after subgrouping using bladder urine SUVmax. This study showed that the distribution of bladder 18F-PSMA-1007 was not correlated with the above clinical and imaging characteristics, so further studies are needed to find the explanations, and thus to improve the disease assessment of this type of prostate cancer patients.

Prediction nomogram based on 18F-FDG PET/CT and clinical parameters for patients with diffuse large B-cell lymphoma.

The objective of this study was to develop a nomogram including parameters assessed by 18F-FDG PET/CT and clinical parameters for patients with diffuse large B-cell lymphoma (DLBCL) to predict progression-free survival (PFS). A total of 181 patients with pathologically diagnosed DLBCL at Sichuan Cancer Hospital and Institute from March 2015 to December 2020 were enrolled in this retrospective study. The area under the receiver operating characteristic (ROC) curve (AUC) was used to calculate the optimal cutoff values of the semiquantitative parameters (SUVmax, TLG, MTV, and Dmax) for PFS. A nomogram was constructed according to multivariate Cox proportional hazards regression. The predictive and discriminatory capacities of the nomogram were then measured using the concordance index (C-index), calibration plots, and Kaplan-Meier curves. The predictive and discriminatory capacities of the nomogram and the International Prognostic Index of the National Comprehensive Cancer Network (NCCN-IPI) were compared via the C-index and AUC. Multivariate analysis demonstrated that male gender and pretreatment Ann Arbor stage III-IV, non-GCB, elevated lactate dehydrogenase (LDH), number of extranodal organ involvement (Neo)>1, MTV≥152.8 cm3, and Dmax ≥53.9 cm were associated with unfavorable PFS (all p<0.05). The nomogram, including gender, Ann Arbor stage, pathology type, Neo, LDH levels, MTV, and Dmax, showed good prediction accuracy, with a C-index of 0.760 (95% CI: 0.727-0.793), which was higher than that of NCCN-IPI (0.710; 95% CI: 0.669-751). The calibration plots for 2-year demonstrated good consistency between the predicted and observed probabilities for survival time. We established a nomogram including MTV, Dmax, and several clinical parameters to predict the PFS of patients with DLBCL, and the nomogram showed better predictability and higher accuracy than NCCN-IPI.

Prognostic significance and postoperative chemoradiotherapy guiding value of mean platelet volume for locally advanced esophageal squamous cell carcinoma patients.

Objective: To investigate the predicting prognosis and guiding postoperative chemoradiotherapy (POCRT) value of preoperative mean platelet volume (MPV) in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC). Methods: We proposed a blood biomarker, MPV, for predicting disease-free survival (DFS) and overall survival (OS) in LA-ESCC patients who underwent surgery (S) alone or S+POCRT. The median cut-off value of MPV was 11.4 fl. We further evaluated whether MPV could guide POCRT in the study and external validation groups. We used multivariable Cox proportional hazard regression analysis, Kaplan-Meier curves, and log-rank tests to ensure the robustness of our findings. Results: In the developed group, a total of 879 patients were included. MVP was associated with OS and DFS defined by clinicopathological variables and remained an independent prognostic factor in the multivariate analysis (P = 0.001 and P = 0.002, respectively). For patients with high MVP, 5-year OS and 0DFS were significantly improved compared to those with low MPV (P = 0.0011 and P = 0.0018, respectively). Subgroup analysis revealed that POCRT was associated with improved 5-year OS and DFS compared with S alone in the low-MVP group (P < 0.0001 and P = 0.0002, respectively). External validation group analysis (n = 118) showed that POCRT significantly increased 5-year OS and DFS (P = 0.0035 and P = 0.0062, respectively) in patients with low MPV. For patients with high MPV, POCRT group showed similar survival rates compared with S alone in the developed and validation groups. Conclusions: MPV as a novel biomarker may serve as an independent prognosis factor and contribute to identifying patients most likely to benefit from POCRT for LA-ESCC.

Comparison of Al 18F-NOTA-FAPI-04 and 18F-FDG in recurrent esophageal cancer after surgery.

Recently, radionuclide labelling fibroblast activating protein inhibitors (FAPI) is regarded as the most promising imaging tracer forvarious tumours. Here we present the imaging finding of aluminium-[18F] fluoride (Al18F)-labelled 1,4,7-triazacyclononane-N,N',N"-triacetic acid (Al18F-NOTA-FAPI-04) and fluorine-18-fluorodeoxyglucose (18F-FDG) in postoperative recurrence esophageal cancer. The results presented that imaging with Al18F-NOTA-FAPI-04 showed significant improvement in detection of local recurrence and distant metastasis with higher maximum standardized uptake value (SUVmax) in the lesions compared with 18F-FDG.

Performance of 18 F-FAPI PET/CT in assessing glioblastoma before radiotherapy: a pilot study.

BACKGROUND: We aimed to determine the performance of 18 F-FAPI PET/CT used for preprocedural assessment of glioblastoma before radiotherapy. METHODS: Twelve glioblastoma patients having undergone incomplete surgical resection or biopsy were examined with 18 F-FAPI PET/CT and MRI scanning before radiotherapy. All patients had confirmed tumor residues according to findings of histopathological and/or long-term clinical and radiological follow-ups. Lesion characterization data, including SUVmax and tumor-to-background ratio (TBR) on PET/CT were attained. PET/CT and MRI findings were compared in terms of number of lesions. The correlation between immunohistochemistry, molecular expression, and PET/CT parameters was also evaluated. RESULTS: 18 F-FAPI PET/CT detected 16 FAPI-avid out of 23 lesions in 12 patients described on MRI. MRI was statistically different from 18 F-FAPI PET/CT for lesion detection according to the exact McNemar statistical test (P = 0.0156). The SUVmax and TBR of the glioblastomas was 7.08 ± 3.55 and 19.95 ± 13.22, respectively. The sensitivity and positive predictive value (PPV) of 18 F-FAPI PET were 69.6% and 100%, respectively. Neither the Ki-67 index nor the molecular expression was correlated with the FAPI-PET/CT parameters. CONCLUSION: 18 F-FAPI PET/CT detects glioblastomas at a lower rate than MRI. However, the 100% PPV of the examination may make it useful for differentiating controversial lesions detected on MRI. The 18 F-FAPI-avid lesions are displayed more clearly probably due to a higher TBR. 18 F-FAPI PET/CT imaging might find application in glioblastoma biopsy and radiotherapy planning.

The prognostic value of positron emission tomography/computed tomography-based parameters in locally advanced esophageal squamous cell carcinoma treated with chemoradiation therapy.

OBJECTIVES: To assess the prognostic value of PET/computed tomography-based parameters in patients with locally advanced esophageal squamous cell carcinoma (ESSC). METHODS: Sixty-seven patients with ESSC undergoing definitive chemoradiotherapy (dCRT) were retrospectively enrolled. PET/CT parameters (maximum standardized uptake value (SUVmax) metabolic tumor volume (MTV), and total glycolysis (TLG) were obtained from 18F-fluorodeoxyglucose (18F-FDG) PET/CT studies. The correlation between overall survival and PET/CT parameters was analyzed using a Cox proportional hazards model. RESULTS: There were no differences in TLG, MTV, and SUVmax values across age, sex, tumor location, and lymph node status. However, for patients with cT3-4 disease, TLG and SUVmax were significantly higher (P = 0.019 and P = 0.018, respectively), and MTV showed an increasing trend (P = 0.068). There were significant correlations among TLG, MTV and SUVmax. According to the receiver-operating curve, the cutoff values of TLG, MTV and SUVmax dichotomized by survival status at 2 years were 64.00 g, 9.63 ml and 9.97 g/ml, respectively. In univariate analysis, increased TLG, MTV and SUVmax were significant negative prognostic factors for OS. However, in multivariate analysis, only SUVmax was an independent prognostic factor for overall survival (hazard ratios = 2.857, 95% confidence intervals: 1.837-4.442; P = 0.017). CONCLUSIONS: PET/CT is a useful tool for predicting the prognoses in patients with locally advanced ESSC treated with dCRT. Future prospective studies with a large number of samples should be conducted to confirm these results.

[The Prognosis Assessment Value of Interim 18F-FDG PET/CT Imaging in the Chemotherapy of Diffuse Large B-cell Lymphoma].

OBJECTIVE: To investigate the prognostic value of interim 18F-FDG PET/CT in patients with diffuse large B-cell lymphoma (DLBCL). METHODS: A total of 97 patients with pathologically diagnosed DLBCL at Sichuan Cancer Hospital and Institute from March 2015 to June 2020 were enrolled in this retrospective study. Receiver operating characteristic analysis (ROC) was used to calculate the optimum maximum standard uptake value reduction ratio (△SUVmax%) cut-off value. The prognostic value of △SUVmax% and Deauville five-point scale (5-PS) in patients with DLBCL was compared, and the determined prognostic factors were analyzed. RESULTS: ROC curve indicated that the optimum △SUV max% cut-off value was 74.9%. Patients with △SUVmax%≥74.9% had a lower rate of progression or recurrence than those with △SUVmax% < 74.9% (both P<0.001). Meanwhile, patients with 5-PS score < 4 also had a lower rate of progression or recurrence than those with 5-PS score≥4 (both P<0.001). △SUVmax% and 5-PS had high specificity (83.7% vs 83.7%) and negative predictive value (87.3% vs 84.9%), while low sensitivity (56.0% vs 52.2%) and positive predictive value (53.8% vs 50.0%). △SUVmax% was more sensitive than 5-PS for the corresponding parameters (78.3% vs 76.2%). Univariate analysis showed that Ann Arbor stage, international prognostic index of National Comprehensive Cancer Network (NCCN-IPI), △SUVmax% and 5-PS were associated with TTP and PFS (all P<0.001). Multivariate analysis showed that △SUVmax% was an independent predictor of TTP and PFS (P=0.031, P=0.023). CONCLUSION: Both 5-PS and △SUVmax% can be used to evaluate the prognosis of DLBCL patients, but the predictive value of △SUVmax% is superior to that of 5-PS.

Physiological tracer distribution and benign lesion incidental uptake of Al18F-NOTA-FAPI-04 on PET/CT imaging.

OBJECTIVE: To systematically investigate the physiological distribution and benign lesion incidental uptake of Al18F-NOTA-FAPI-04 (18F-FAPI) in cancer patients to establish the normal uptake range in relevant organs and lesions. METHODS: Twenty patients who underwent 18F-FAPI PET/CT imaging were retrospectively assessed. Organ and benign lesion tracer uptake was quantified based on standardized uptake values (SUVmax and SUVmean). We compared the variation in tracer uptake in certain organs between men and women, analyzed the possible reasons for diffuse uptake in the thyroid, and assessed tracer uptake variations in the uterus in different menstrual cycle phases. Incidental tracer uptake in benign lesions was also assessed. RESULTS: Physiological 18F-FAPI uptake was observed in the urinary tract, biliary tract system, submandibular glands, pancreas, thyroid, uterus, intestine, prostate gland, parotid gland, myocardium, kidney cortex, and muscles, but not the brain, lungs, liver, spleen, colon, and breasts. The SUVmean for each organ was similar for women and men (all P > 0.05). Diffuse tracer uptake in the thyroid was caused by normal thyroid or thyroiditis; there were no statistically significant differences between them (SUVmax: t = -1.3, P = 0.25; SUVmean: t = -1.1, P = 0.31). There was a significant difference for uterus uptake among different menstrual cycle phases (SUVmax: F = 5.08, P = 0.04; SUVmean: F = 5.19, P = 0.04). Incidental benign lesion tracer uptake was observed in patients with esophagitis, thyroiditis, arthritis, fractures, and uterine fibroids. CONCLUSION: This study provides a reference range for 18F-FAPI uptake in relevant organs and benign lesions. Benign lesion 18F-FAPI uptake may reduce 18F-FAPI PET/CT specificity.

Evaluation of 18F-PSMA-1007 PET/CT in prostate cancer patients with biochemical recurrence after radical prostatectomy.

PURPOSE: Prostate-specific membrane antigen (PSMA) ligands targeting has shown promising results in staging of prostate cancer (PCa). The aim of present study was to evaluate the value of 18F-PSMA-1007 PET/CT in PCa patients with biochemical recurrence. METHODS: 71 patients with PCa after radical prostatectomy (RP) were included in the present study. Median prostate-specific antigen (PSA) level was 1.27 ng/mL (range 0.01-67.40 ng/mL, n = 69). All patients underwent whole-body PET/CT imaging after injection of 333±38 MBq 18F-PSMA-1007. The distribution of PSMA-positive lesions was assessed. The influence of PSA level, androgen deprivation therapy and primary Gleason score on PSMA-positive finding and uptake of 18F-PSMA-1007 were evaluated. RESULTS: 56 (79%) patients showed at least one pathological finding on 18F-PSMA-1007 PET/CT. The rates of positive scans were 50%, 80%, 100%, 100% among patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and >2.0 ng/mL, respectively. The median Gleason score was 8 (range 7-10), and higher Gleason score (≤7 vs. ≥8) leads to higher detection rates (58.3% (14/24) vs. 88.9% (32/36), P = 0.006). The median SUVmax of positive findings in patients with PSA levels ≤0.5, 0.51-1.0, 1.1-2.0 and >2.0 ng/mL were 4.51, 4.27, 11.50 and 14.08, respectively. The median SUVmax in patients with PSA level >2.0 ng/mL was significantly higher than that in patients with PSA ≤2.0 ng/mL (14.08 vs. 6.13, P<0.001). CONCLUSION: 18F-PSMA-1007 PET/CT demonstrated a high detection rate for patients with a raised PSA level after radical prostatectomy even in patients with extremely low PSA level (eg. PSA level ≤0.5 ng/mL), which was essential for further clinical management for PCa patients.

Predictive Value of Gross Extranodal Extension for Differentiated Thyroid Carcinoma Persistence/Recurrence.

OBJECTIVE: We systematically investigated the predictive value of gross extranodal extension (gENE) for differentiated thyroid carcinoma persistence/recurrence. STUDY DESIGN: Retrospective study. SETTING: A tertiary care hospital. METHODS: This study was divided into 2 groups according to gENE status: the gENE group and non-gENE group. We compared the disease persistence/recurrence rates of these 2 groups in the entire cohort and by individual risk group (intermediate/high risk), analyzed whether gENE was an independent risk factor for disease persistence/recurrence, and explored the impact of gENE-specific features on disease persistence/recurrence. RESULTS: There were 989 patients who satisfied the inclusion criteria: 57 patients in the gENE group and 932 in the non-gENE group. The disease persistence/recurrence rate of the gENE group was higher than that of the non-gENE group in the entire cohort and by individual risk group (P < .05 for each). Unexpectedly, the outcomes of the gENE group with intermediate risk were similar to those of the non-gENE group with high risk (P = .72). For the entire cohort, gENE was an independent predictor for disease persistence/recurrence (odds ratio, 2.89; 95% CI, 1.39-6.00; P = .005). Specific features of gENE (P > .05 for each) were not related to disease persistence/recurrence. CONCLUSION: Patients with gENE and intermediate risk might be regraded as high risk. Specific features of gENE have no impact on disease persistence/recurrence.

Hepatic Lesion of Mucosa-Associated Lymphoid Tissue Lymphoma Revealed by Al18F-NOTA-FAPI-04 PET/CT.

ABSTRACT: A middle-aged man was newly diagnosed with mucosa-associated lymphoid tissue lymphoma with secondary liver involvement. The hepatic lesion was not shown on FDG PET/CT but FAPI (fibroblast-activated protein inhibitor) PET/CT, which revealed abnormal FAPI accumulation. This case demonstrated that FAPI PET/CT might provide value in hepatic mucosa-associated lymphoid tissue lymphoma.

Al18F-NOTA-FAPI-04 Outperforms 18F-FDG PET/CT in Identifying the Primary Lesion and Rare Metastases From Gastric Cancer.

ABSTRACT: A 45-year-old woman with gastric cancer underwent FDG PET/CT for initial staging. However, the primary and the metastatic lesions were observed with low or no FDG uptake. Then, the patient underwent fibroblast-activated protein inhibitor PET/CT 2 days later, which demonstrated more lesions and much higher tumor-to-background contrast than FDG PET/CT did.

FAPI-04 PET/CT Using [18F]AlF Labeling Strategy: Automatic Synthesis, Quality Control, and In Vivo Assessment in Patient.

68Ga labeled FAPI is the current standard for FAPI-PET, but its batch activity is limited. [18F]AlF-NOTA-FAPI-04 is a promising alternative combining the advantages of a chelator-based radiolabeling method with the unique properties of fluorine-18. The objective of this study was to develop a quick automatic method for synthesis of [18F]AlF-NOTA-FAPI-04 using a AllinOne synthesis system, and perform PET imaging with [18F]AlF-NOTA-FAPI-04 on patients. [18F]AlF-NOTA-FAPI-04 was produced, and its quality control was conducted by HPLC equipped with a radioactive detector. [18F]AlF-NOTA-FAPI-04 PET/CT imaging was performed in normal BALB/c mice (n = 3) and 4T1 breast cancer models (n = 3) to determine its biodistribution. Then [18F]AlF-NOTA-FAPI-04 and 18F-fluorodeoxyglucose (FDG) PET/CT imaging were performed in an invasive ductal carcinoma patient (female, 54 years old). The synthesis time of [18F]AlF-NOTA-FAPI-04 was about 25 min, and the radiochemical yield was 26.4 ± 1.5% (attenuation correction, n = 10). The radiochemical purity was above 99.0% and was above 98.0% after 6 h. The product was colorless transparent solution with pH value of 7.0-7.5, and the specific activity was 49.41 ± 3.19 GBq/µmol. PET/CT imaging in mice showed that physiological uptake of [18F]AlF-NOTA-FAPI-04 was mainly in the biliary system and bladder, and [18F]AlF-NOTA-FAPI-04 highly concentrated in tumor xenografts. PET/CT imaging in the patient showed that [18F]AlF-NOTA-FAPI-04 obtained high tumor background ratio (TBR) value of 8.44 in segment V and VI, while TBR value was 2.55 by 18F-FDG. [18F]AlF-NOTA-FAPI-04 could be synthesized with high radiochemical yield and batch production by AllinOne module and show excellent diagnosis performance in cancer patients.

Quick Automatic Synthesis of Solvent-Free 16α-[18F] Fluoroestradiol: Comparison of Kryptofix 222 and Tetrabutylammonium Bicarbonate.

Estrogen receptor (ER) expression level of human breast cancer often reflects the stage of disease and is usually monitored by immunohistochemical staining in vitro. The preferable non-invasive and real-time diagnosis in vivo is more accessible by PET scan using 16α-[18F]FES. The objective of this study was to develop a quick automatic method for synthesis of solvent-free 16α-[18F]FES using a CFN-MPS-200 synthesis system and compare the catalytic efficiency of two phase transfer catalysts, Kryptofix 222/K2CO3 (K222/K2CO3) and tetrabutylammonium hydrogen carbonate (TBA·HCO3). In this method, phase transfer catalysts K222/K2CO3 and TBA·HCO3 were used, respectively. The intermediate products were both hydrolyzed with hydrochloric acid and neutralized with sodium bicarbonate. The crude product was purified with semi-preparative HPLC, and the solvent was removed by rotary evaporation. The effects of radiofluorination temperature and time on the synthesis were also investigated. Radiochemical purity of solvent-free product was above 99% and the decay-corrected radiochemical yield of 16α-[18F]FES was obtained in 48.7 ± 0.95% (catalyzed by K222/K2CO3, n = 4) and 46.7 ± 0.77% (catalyzed by TBA·HCO3, n = 4, respectively). The solvent-free 16α-[18F]FES was studied in clinically diagnosed breast cancer patients, and FES-PET results were compared with pathology diagnosis results to validate the diagnosis value of 16α-[18F]FES. The new method was more reliable, efficient, and time-saving. There was no significant difference in catalytic activity between K222/K2CO3 and TBA·HCO3.