Risk factors of bladder stones in neurogenic lower urinary tract dysfunction: A real-world study.

Objective: The objective of this study is to investigate the incidence and risk factors for stone formation and recurrence in patients with neurogenic lower urinary tract dysfunction (NLUTD) in a real-world cohort. Materials and methods: A retrospective cohort study was conducted on all patients with NLUTD who underwent bladder stone treatment between 2010 and 2022. Univariate and multivariate Cox models were used to identify the potential risk factors for stone recurrence. Results: Among 114 patients included in the study, 30% experienced stone recurrence. The most common stone components were carbonate apatite phosphate and magnesium ammonium phosphate. The overall recurrence rate was 14 cases per 100 patient years. Neurogenic detrusor overactivity had the highest recurrence rate. Risk factors for stone recurrence in the multivariate analysis were intermittent and suprapubic catheterization, and recurrent urinary tract infection (rUTI). Conclusions: Patients experienced multiple bladder stone recurrences. Close monitoring of bladder pressure and UTI with restrictive catheter application may reduce the risk of stone recurrence.

68Ga-PSMA-11 PET imaging in patients with ongoing androgen deprivation therapy for advanced prostate cancer.

PURPOSE: Prostate-specific membrane antigen (PSMA) targeted positron emission tomography (PET) imaging significantly improved the detection of recurrent prostate cancer (PCa). However, the value of PSMA PET imaging in patients with advanced hormone-sensitive or hormone-resistant PCa is still largely unknown. The aim of this study was to analyze the detection rate and distribution of lesions using PSMA PET imaging in patients with advanced PCa and ongoing androgen deprivation therapy (ADT). METHODS: A total of 84 patients diagnosed with hormone-sensitive or hormone-resistant PCa who underwent 68Ga-PSMA-11 PET/magnetic resonance imaging (MRI) or computer tomography (CT) under ongoing ADT were retrospectively analyzed. We assessed the detection of PSMA-positive lesions overall and for three PSA subgroups (0 to < 1 ng/mL, 1 to < 20 ng/mL and > 20 ng/mL). In addition, PSMA-positive findings were stratified by localization (prostatic fossa, pelvic, para-aortic, mediastinal/supraclavicular and axillary lymph nodes, bone lesions and visceral lesions) and hormone status (hormone-sensitive vs. hormone-resistant). Furthermore, we assessed how many patients would be classified as having oligometastatic disease (≤ 3 lesions) and theoretically qualify for metastasis-directed radiotherapy (MDRT) in a personalized patient management. RESULTS: We detected PSMA-positive lesions in 94.0% (79 of 84) of all patients. In the three PSA subgroups detection rates of 85.2% (0 to < 1 ng/mL, n = 27), 97.3% (1 to < 20 ng/mL, n = 37) and 100% (> 20 ng/mL, n = 20) were observed, respectively. PSMA-positive visceral metastases were observed only in patients with a PSA > 1 ng/mL. Detection of PSMA-positive lesions did not significantly differ between patients with hormone-sensitive and hormone-resistant PCa. Oligometastatic PCa was detected in 19 of 84 patients (22.6%). Almost all patients, 94.7% (n = 18) would have been eligible for MDRT. CONCLUSIONS: In this study, we observed an overall very high detection rate of 94% using PSMA PET imaging in patients with advanced PCa and ongoing ADT. Even in a majority of patients with very low PSA values < 1 ng/ml PSMA-positive lesions were found.

A pilot study on lung cancer detection based on regional metabolic activity distribution in digital low-dose 18F-FDG PET.

OBJECTIVES: To investigate the potential of automatic lung cancer detection on submillisievert dose 18F-fludeoxyglucose (18F-FDG) scans using different positron emission tomography (PET) parameters, as a primary step towards a potential new indication for 18F-FDG PET in lung cancer screening. METHODS: We performed a retrospective cohort analysis with 83 patients referred for 18F-FDG PET/CT, including of 34 patients with histology-proven lung cancer and 49 patients without lung disease. Aside clinical standard PET images (PET100%) two additional low-dose PET reconstructions were generated, using only 15 s and 5 s of the 150 s list mode raw data of the full-dose PET, corresponding to 10% and 3.3% of the original 18F-FDG activity. The lungs were subdivided into three segments on each side, and each segment was classified as normal or containing cancer. The following standardized uptake values (SUVs) were extracted from PET per lung segment: SUVmean, SUVhot5, SUVmedian, SUVstd and SUVtotal. A multivariate linear regression model was used and cross-validated. The accuracy for lung cancer detection was tested with receiver operating characteristics analysis and T-statistics was used to calculate the weight of each parameter. RESULTS: The T-statistics showed that SUVstd was the most important discriminative factor for lung cancer detection. The multivariate model achieved an area under the curve of 0.97 for full-dose PET, 0.85 for PET10% with PET3.3% reconstructions resulting in a still high sensitivity the PET10% reconstruction of 80%. CONCLUSION: This pilot study indicates that segment-based, quantitative PET parameters of low-dose PET reconstructions could be used to automatically detect lung cancer with high sensitivity. ADVANCES IN KNOWLEDGE: Automated assessment of PET parameters in low-dose PET may aid for an early detection of lung cancer.