Meningioma uptake of 68Gallium-PSMA-11 as a pitfall on positron emission tomography/computer tomography

Prostate cancer is the most common malignancy in men with high incidence of recurrence following treatment. Biochemical recurrence, as indicated by rising PSA levels following successful treatment of the primary disease, is a frequent encounter in routine clinical practice. 68Gallium-PSMA positron emission tomography/computer tomography has been widely accepted as the modality of choice with the highest impact in management of this group of patients. Pitfalls of this diagnostic technique stem from the diversity of histological entities, other than prostate tumour cells, which can demonstrate increased uptake of the radiotracer. We present a case of intracranial uptake of PSMA by meningioma in a patient with BCR, as a pitfall in imaging of prostate cancer. Knowledge of normal distribution of the tracer is of utmost importance when reading positron emission tomography/computer tomography imaging especially given the relative novelty of usage of 68Gallium-PSMA.

Tuberculosis-associated HLH in a patient with chronic kidney disease on haemodialysis

Haemophagocytic lymphohistiocytosis (HLH) is a rare immunological disorder that is accompanied by a high mortality rate when the underlying aetiology is miliary tuberculosis. We report a case of tuberculosis (TB)-associated HLH in a haemodialysis patient, from a TB-endemic region, who missed two sessions of dialysis before developing the primary symptoms of HLH. The patient presented with non-specific findings including pancytopenia, coagulopathy and transaminitis. Computer-tomography imaging and microbiology from bronchoalveolar lavage evidenced miliary tuberculosis. Further testing revealed the TB-associated-HLH characteristic pattern of thrombocytosis, leukopenia, transaminitis, hyperferritinemia and elevated fibrinogen. The patient initially demonstrated improvement after initiation of anti-TB therapy. However, soon thereafter began to paradoxically deteriorate and then expire from apparent tuberculosis-immune reconstitution inflammatory syndrome. This case highlights the importance of early diagnosis and treatment, and consequently of the utility of diagnostic systems such as the HScore in cases of high clinical suspicion.

Renal Tumors in Young Adults: Is Preoperative Computer Tomography Imaging Suggestive for the Nature of the Tumors?

Renal cell carcinoma (RCC) accounts for 2–3% of all adult malignant neoplasms and is even rarer in patients under 45 years old. Clear-cell carcinoma represents most of the pathological subtypes. Our study aimed to investigate the association between preoperative computer tomography imagistic evaluation and histopathological diagnosis of renal tumors in young adults. Patients younger than 45 years old with renal tumors who were referred for medical treatment at the Clinical Institute of Urology and Renal Transplantation Cluj-Napoca from 2012 to 2019 were considered eligible for the study. Medical charts were retrospectively reviewed, and patients with complete data regarding preoperative diagnostic, histopathological evaluation, and follow-up data, regardless of gender, were included in the study. Sixteen patients younger than 45 years fulfilled all the inclusion criteria and were evaluated. With two exceptions, the evaluated patients were in a T1 and T2 stage, with no vascular invasion or of the adjacent organs. Two-thirds of our patients had a clear-cell renal cell carcinoma. None of our patients fitted in the low complexity surgery category of the R.E.N.A.L. Nephrometry Score and 37.5% of them benefited from partial nephrectomy. Half of the suppositions made based on imaging were concordant with the histopathology report. Fifteen of the patients showed no recurrence during the respective follow-up interval. Computer tomography imaging reports showed on our sample a higher concordance with the histopathological report in the more common subtypes (namely Renal Clear Cell RCC), with typical appearances.

A Novel Pet Tracer 18f-labeled Thiamine: Synthesis, Metabolic Kinetics, and Evaluation on Cerebral Thiamine Metabolism Status

Background:Someneuropsychological diseases are associated with abnormal thiamine metabolism, including Korsakoff-Wernicke syndrome and Alzheimer’s disease. However, in vivo detection of brain thiamine metabolism status isstill unavailable and needs to be developed.Methods:A novel PET tracer 18F-labeled thiaminewasautomatically radio-synthesized via a two-step route. The main parameters of characterization were proved by high performance liquid chromatography (HPLC). Metabolic kinetics of 18F-labeled thiamine and the status of cerebral thiamine uptakein mice and marmosets were studied by micro-positron emission tomography (PET)/computer tomography imaging. Also, in vivo stability, renal excretion rate, biodistribution, and the correlation between cerebral 18F-labeled thiamine retention and blood thiamine levels were investigated.Results: The 18F-labeled thiamine was stableboth in vitro and in vivoand manifested fast uptake and clearance in vivo. The biodistribution of 18F-labeled thiamine were consistent with previously reports on thiamine distribution in mice. The retention of cerebral 18F-labeled thiamine was higher in mice with thiamine deficiency than that in control mice, and negatively correlated with blood thiaminediphosphate levels in marmosets.Conclusion:The 18F-labeled thiamine met the requirements for ideal PET tracer to in vivoevaluate the status of cerebral thiamine metabolism. This study laid the foundation for further studies on the relevant diseases.