Background At least 20% of the future liver remnant must function properly after liver tumor resection to avoid post-hepatectomy liver failure (PHLF). [^99mTc]Tc-mebrofenin scintigraphy and SPECT are unique noninvasive, quantitative methods for evaluating liver function via hepatocellular bilirubin clearance. Aim To evaluate the value of dynamic [^99mTc]Tc-mebrofenin SPECT/CT parameters for predicting clinically relevant PHLF according to the ISGLS criteria. Methods Thirty-five patients underwent dynamic [^99mTc]Tc-mebrofenin SPECT/CT imaging to determine the FLR volumetric rate, functional volume rate, total liver filtration and FLR filtration. On the same day, two-dimensional ultrasound shear wave elastography (2D-SWE) was used to assess parenchymal fibrosis in the FLR. The quantitative dynamic SPECT parameters were compared with the relevant clinical scores and ICG. Results The total liver filtration was inversely correlated with the ICG-R15 and MELD-Na score. Twenty-four patients underwent major liver resection due to an adequate FLR rate and did not die within 90 days after the procedure. ROC analysis revealed that the FLR filtration was a significant predictor of PHLF. The best cutoff value for FLR filtration was 2.72%/min/m². Conclusion Dynamic [^99mTc]Tc-mebrofenin SPECT/CT is an essential tool for selecting patients at risk of clinically relevant PHLF after liver resection.

Background: Numerous PSMA-based tracers are used for diagnostic prostate cancer imaging, but comprehensive comparisons between multiple ligands are lacking. This study aimed to compare physiological skeletal uptake and tracer uptake in commonly recommended PSMA reference regions across three different PSMA ligands in prostate cancer patients. Methods: A total of 281 prostate cancer patients were included. Using PET and SPECT imaging, target volumes of interest were defined via a semiautomatic method, and standardized uptake values (SUV) were calculated for the skeletal system and reference regions (liver, spleen, parotid gland, and blood pool). Results: Significant differences in SUV uptake were observed, with [¹⁸F]F-PSMA-1007 showing higher SUV values in the skeletal system. The parotid gland displayed the highest variability in uptake, while the blood pool and liver exhibited more homogeneous uptake across patients. Conclusions: While radioligands behave similarly in bone regions, there are notable differences in SUV patterns, particularly for PSMA-1007, which showed higher bone uptake. Parotid gland uptake variability suggests a reconsideration of its suitability as a reference region, while the liver, spleen, and blood pool showed more consistent uptake. During comparison, the technetium-labeled SPECT ligand proved as similarly effective as the two PET ligands for diagnostic imaging.

Bevezetés: A nagyérvasculitisek nem specifikus klinikai tüneteket okoznak, ami a diagnózist nagyban nehezíti. A betegség korai felismerése és kezelése a későbbi szövődmények elkerülése érdekében fontos. A ¹⁸F-FDG-PET az érfalon belüli gyulladást a betegség korai stádiumában is nagy érzékenységgel mutatja ki. A CT a nagyérvasculitis pontos lokalizációjában van segítségünkre. Célkitűzés: A ¹⁸F-FDG-PET/CT teljesítőképességének tisztázása a betegség aktivitásának és kiterjedésének megítélésében: klinikailag nagyérvasculitis iránydiagnózisával vizsgált betegekben és relapsus során, valamint a terápiára létrejövő remissio megállapításában. Módszer: A vizsgálatban 43 beteg vett részt. A betegeket a klinikai kérdés alapján csoportosítottuk: primer diagnózis igazolása szteroidnaiv és szteroiddal kezelt betegekben, relapsus, illetve remissio kimutatása. Kontrollként 10, gyulladásos tünetektől mentes tumoros beteget vizsgáltunk meg. Az erek radiofarmakon-felvételének mértékét vizuálisan és kvantitatívan értékeltük. A kvantitatív értékelés során az érszegmentumokban a májhoz viszonyított érfal maximális standard ¹⁸F-FDG-felvételi értékét (SUVmax) határoztuk meg. Eredmények: A primer diagnózis céljából végzett 30 vizsgálatból 5 esetben ¹⁸F-FDG-aktív nagyérvasculitist mutattunk ki, további 13 vizsgálatból 5 betegben pedig relapsust igazoltunk. A vizuálisan aktív betegek 50%-ában 3 vagy annál több aktív érszegmentumot találtunk. A vizuálisan aktív betegcsoportban szteroid hatására az érfal SUVmax-értéke szignifikánsan alacsonyabb volt a szteroidnaiv betegekhez képest (1,17 ± 0,11 vs. 1,43 ± 0,29; p = 0,005). Két ¹⁸F-FDG-aktív nagyér-vasculitises betegben kontrollvizsgálattal remissiót állapítottunk meg. A primer diagnózis céljából vizsgált esetek közül 8-ban egyéb, a nagyérvasculitistől független gyulladásos kórképet mutattunk ki. Következtetés: A ¹⁸F-FDG-PET/CT hatékonyan alkalmazható az aktív nagyérvasculitisek diagnosztizálásában. A metabolikus változás nagy érzékenységű megjelenítése mellett az érintett erek pontos lokalizációját is lehetővé teszi. A szteroidterápia befolyásolja az érfalak ¹⁸F-FDG-felvételét. Orv Hetil. 2020; 161(20): 829–838.

Background/Objectives: Neuroendocrine neoplasms (NENs) are a diverse group of malignancies in which somatostatin receptor expression can be crucial in guiding therapy. We aimed to evaluate the effectiveness of [^99mTc]Tc-EDDA/HYNIC-TOC SPECT/CT in differentiating neuroendocrine tumor histology, selecting candidates for radioligand therapy, and identifying correlations between somatostatin receptor expression and non-imaging parameters in metastatic NENs. Methods: This retrospective study included 65 patients (29 women, 36 men, mean age 61) with metastatic neuroendocrine neoplasms confirmed by histology, follow-up, or imaging, comprising 14 poorly differentiated carcinomas and 51 well-differentiated tumors. Somatostatin receptor SPECT/CT results were assessed visually and semi-quantitatively, with mathematical models incorporating histological, oncological, immunohistochemical, and laboratory parameters, followed by biostatistical analysis. Results: Of 392 lesions evaluated, the majority were metastases in the liver, lymph nodes, and bones. Mathematical models estimated somatostatin receptor expression accurately (70-83%) based on clinical parameters alone. Key factors included tumor origin, oncological treatments, and the immunohistochemical marker CK7. Associations were found with age, grade, disease extent, and markers (CEA, CA19-9, AFP). Conclusions: Our findings suggest that [^99mTc]Tc-EDDA/HYNIC-TOC SPECT/CT effectively evaluates somatostatin receptor expression in NENs. Certain immunohistochemical and laboratory parameters, beyond recognised factors, show potential prognostic value, supporting individualised treatment strategies.

Background: Neuroendocrine neoplasms (NENs) are a diverse group of malignancies in which somatostatin receptor expression can be crucial in guiding therapy. We aimed to evaluate the effectiveness of [^99mTc]Tc-EDDA/HYNIC-TOC SPECT/CT in differentiating neuroendocrine tumor histology, selecting candidates for radioligand therapy, and identifying correlations between somatostatin receptor expression and non-imaging parameters in metastatic NENs. Methods: This retrospective study included 65 patients (29 women, 36 men, mean age 61) with metastatic neuroendocrine neoplasms confirmed by histology, follow-up, or imaging, comprising 14 poorly differentiated carcinomas and 51 well-differentiated tumors. Somatostatin receptor SPECT/CT results were assessed visually and semiquantitatively, with mathematical models incorporating histological, oncological, immunohistochemical, and laboratory parameters, followed by biostatistical analysis. Results: Of 392 lesions evaluated, the majority were metastases in the liver, lymph nodes, and bones. Mathematical models estimated somatostatin receptor expression accurately (70–83%) based on clinical parameters alone. Key factors included tumor origin, oncological treatments, and the immunohistochemical marker CK7. Associations were found between age, grade, disease extent, and markers (CEA, CA19-9, AFP). Conclusions: Our findings suggest that [^99mTc]Tc-EDDA/HYNIC-TOC SPECT/CT effectively evaluates somatostatin receptor expression in NENs. Certain immunohistochemical and laboratory parameters, beyond recognized factors, show potential prognostic value, supporting individualized treatment strategies.

Peripheral T-cell lymphomas (PTCLs) are malignancies of mature T cells with a poor prognosis. Most PTCL cases express follicular T-helper (T_FH) cell antigens and are classified as T_FH cell lymphoma (TFHL). Contact-dependent signaling between CD40 and its ligand, CD154, is essential for immune functions. CD154 is expressed by activated T cells, while CD40 is found on B cells, follicular and other dendritic cells, macrophages, and stromal cells. Although the CD40–CD154 crosstalk is a key costimulatory pathway in immune responses, data on its role in PTCLs are limited. To explore the role of the CD40–CD154 axis in TFHLs, we conducted an in-depth immunomorphological study of 111 PTCL cases, including 93 TFHL cases. We found that neoplastic T cells in TFHL are consistently CD154-positive. The CD154 expression increased in histologically advanced cases and correlated with the extent of CD40 positivity. We showed that CD154-positive neoplastic T cells recapitulate the intranodal migration of normal TFH cells, disrupting and remodeling each functional compartment, thereby explaining the disease-related immune dysfunction. Our findings indicate that pathological CD40–CD154 interaction is a potential driver mechanism in TFHL and offers a promising target for future therapies.