Erdheim–Chester disease (ECD) is a rare multi-systemic form of histiocytosis. Treatment with BRAF inhibitors has markedly improved outcomes of ECD; however, this targeted therapy is expensive (estimated annual cost is $50,000). Since estimated annual cost of interferon-α (IFN-α) is only approximately $1600 in China, we retrospectively evaluated the long-term therapeutic efficacy of IFN-α and the value of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) as an assessment method among 32 ECD patients who received high dose IFN-α therapy at Peking Union Medical College Hospital. The median age at diagnosis was 48 years (range, 6–66 years). The median duration of treatment was 18.5 months (range, 1–51 months). The overall clinical response rates were 80.0%, including 33.3% complete response, 36.7% partial response and 10.0% stable disease. Thirty-one patients underwent a total of 81 scans by FDG-PET. Seventeen patients had serial FDG-PET results, nine patients had experienced a partial metabolic response at the last follow-up. The median reduction of ratios between the most active target lesion standardized uptake value (SUV) and liver SUV from baseline to last FDG-PET scan was 61.4% (range, 8.8–86.6%). Eight of thirteen patients who experienced continuous clinical improvement during follow-up had at least one target lesion SUV increased by FDG-PET which decreased in subsequent scans without changing treatment strategy. The estimated 3-year progression-free survival (PFS) and overall survival (OS) were 64.1 and 84.5%, respectively. Central nervous system (CNS) involvement was the only predictor for poor PFS and OS. High-dose IFN-α treatment is a cost-effective option, especially for patients without CNS involvement. Single target lesion SUV elevation according to FDG-PET do not accurately demonstrate disease progression, but serial FDG-PET imaging effectively discriminate treatment response.

Background: This pilot study is aimed to perform a pilot visualization study to investigate in vivo fibroblast activation in non-ischemic cardiomyopathies by ⁶⁸Ga-FAPI-04 PET/CT. Methods: Twenty-nine consecutive patients with symptomatic non-ischemic cardiomyopathies who underwent ⁶⁸Ga-FAPI-04 PET/CT were prospectively recruited. Clinical characteristics and echocardiographic parameters were recorded. Cardiac uptake was quantified by standardized uptake values (SUV_max, SUV_mean, SUVR) and left ventricular metabolism volume. The relationship between ⁶⁸Ga-FAPI-04 uptake with clinical and echocardiography parameters was investigated. Results: Heterogeneous ⁶⁸Ga-FAPI-04 uptake was observed in different subtypes of non-ischemic cardiomyopathies. Twenty-two (75.9%) patients showed elevated ⁶⁸Ga-FAPI-04 uptake in the left ventricle, and 10 (34.5%) patients also showed slightly diffuse elevated uptake in the right ventricle. Cardiac uptake values were significantly correlated with enlarged ventricular volume evaluated by echocardiography. Conclusion: FAPI PET/CT presents a potential value for in vivo visualization and quantification of fibroblast activation on the molecular level. Further study is warranted for investigating the theranostic and prognostic value of elevated FAP signal.

In this work, a new polycyclic phenyl grafted polysiloxane called DFP-15 (15.1% 3,4-2(trifluoromethyl phenyl)-2,5-diphenyl phenyl) was synthesized by the Diels–Alder reaction of tetraphenyl cyclopentadienone monomer containing trifluoromethyl groups with methyl vinyl polysiloxanes composed of 18% methyl vinyl and 82% dimethyl groups. A second chemical called DFP-8 was also prepared for comparison purposes. The thermal stability was evaluated by thermogravimetric analysis, and the results revealed that both of the DFPs had similar thermal stability, and they began to decompose slightly at 380 °C. Subsequently, the copolymers were coated on fused silica capillary columns by static coating and used as a stationary phase and were characterized. The column efficiencies of the DFP-15 and DFP-8 columns were 3960 plates per m (k = 1.90, naphthalene) and 3740 plates per m (k = 1.74, naphthalene), respectively. The excellent film-forming ability in the inner surface of the fused silica capillary columns was proven by the analysis of Grob reagent. Furthermore, the selectivity of the novel stationary phases for analytes, including substituted benzene isomers and polycyclic aromatic hydrocarbons, was evaluated. This work suggests that both of the stationary phases have great potential for further development and application.

A 47-year-old female with cardiac dysfunction and lymphadenopathy underwent ¹⁸FDG PET/CT and ⁶⁸Ga-FAPI-04 imaging for tumor screening. Mild uptake in the left ventricular wall was detected on the oncology ¹⁸FDG PET/CT. True myocardiac-involvement could not be distinguished with physiological uptake. The following ⁶⁸Ga-FAPI-04 showed intense heterogeneous uptake in the left ventricular wall, particularly in the septum and apex area, corresponding with the late gadolinium enhancement regions shown by cardiac MR. Intense uptake was also noted in the mediastinal and bilateral hilar lymph nodes. Endomyocardial biopsy demonstrated sarcoidosis.