Background: Neuroendocrine neoplasms are a group of tumors deriving from neural crest. They can be located in every tissue, but most commonly in gastrointestinal tract. Targeted therapy with use of radionuclides is an available and acceptable way of treatment, but its long-term safety is still to be determined, especially with sensitive methods. Methods: Study was performed on a group of 42 patients. They underwent full cycle (4 courses; 8–12 weekly intervals) of radioligand therapy with [¹⁷⁷Lu]Lu-DOTATATE alone or tandem therapy with [¹⁷⁷Lu]Lu-DOTATATE+[⁹⁰Y]Y-DOTATATE. Late and long-term marrow and renal complications were assessed. Analysis focused on comparing data before first, fourth, and one year after the last course of RLT. Results: Study showed decreasing of all blood parameters in long-term observation, especially in lymphocytes line. Type of radioisotope, other diseases, primary tumor location, BMI, gender or age did not affect results. The only factor that had influence on hemoglobin and erythrocytes was decreased renal filtration. In long-term observation almost 10% decrease of renal filtration was observed. Type of isotope, gender, age, BMI did not affect these results. Moreover, reduction of urine IL-18, KIM-1, and albumin concentration has been observed. Conclusions: Though low-grade complications of radioligand therapy are possible, it stay a safe method of NEN treatment where benefits outweigh the risk.

Neuroendocrine neoplasms (NENs) are a group of neoplasms arising from neuroendocrine cells. The worldwide incidence and prevalence of the NENs are estimated to be 6/100,000 and 35/100,000, respectively. Those numbers are increasing every decade, requiring higher and higher diagnosis and treatment costs. Radioligand therapy (RLT) using beta-emitting radioisotopes is an efficient and relatively safe method of treatment, typically used as a second-line treatment. RLT tolerability is higher than other available pharmacotherapies (chemotherapy or tyrosine kinase inhibitors). Recent studies show an increase in overall survival among patients treated with RLT. The present study aimed to learn the epidemiology of NENs in Poland and assess the effectiveness of RLT in a high-reference center. A prospective analysis of 167 patients treated with RLT in one of Poland’s highest-reference NEN centers was performed. The analysis covered 66 months of observation (1 December 2017–30 May 2023), during which 479 RLT single administrations of radioisotope were given. The standard procedure was to give four courses of [¹⁷⁷Lu]Lu-DOTA-TATE alone, or tandem therapy—[¹⁷⁷Lu]Lu-DOTA-TATE and [⁹⁰Y]Y-DOTA-TATE. Grading analysis showed that most patients had non-functioning G2 NEN with a mean Ki-67 of 6.05% (SD ± 6.41). The most common primary tumor location was the pancreas. Over two-thirds of patients did undergo surgery due to primary tumors or distant metastases. The majority of patients were using lanreotide as a chronically injected somatostatin analog. Median progression-free survival (PFS) on somatostatin analogs was 21.0 (IQR = 29.0) months. Directly after the last course of RLT, disease stabilization was noted in 69.46% of patients, partial regression was noted in 20.36% of patients, complete regression was noted in 0.60% of patients, and progression was noted in 9.58% of patients. In long-term follow-up, the median observation time among patients who underwent four treatment cycles (n = 108) was 29.8 (IQR = 23.9) months. Stabilization of the disease was observed in 55.56% of the patients and progression was observed in 26.85% of the patients, while 17.59% of patients died. Median PFS was 29.3 (IQR 23.9), and the median OS was 34.0 months (IQR 16.0). The mean age of NEN diagnosis is the sixth decade of life. It takes almost three years from NEN diagnosis to the start of RLT. In long-term observation, RLT leads to disease stabilization in over half of the patients with progressive disease. No differences in PFS or OS depend on the radioisotope used for RLT. In Poland, organized coordination of NEN treatment in high-reference centers ensures the continuity of patient care.

Introduction: Tertiary hyperparathyroidism (tHP) may develop in patients treated with hemodialysis or peritoneal dialysis. Parathyroidectomy may result in a significant reduction in the severity of symptoms. For the effective surgical treatment of hyperparathyroidism, proper localization of the parathyroid glands prior to surgery is essential. The sensitivity of scintigraphy in the diagnosis of tHP is lower than in the diagnosis of primary hyperparathyroidism. In recent years, positron emission tomography (PET/CT) has been gaining importance, usually as a complementary technique. Aim: The aim of this study was to determine the usefulness of PET/CT with [¹¹C]MET in the preoperative localization diagnosis of patients with tertiary hyperparathyroidism caused by chronic kidney disease, in whom first-line diagnostic methods did not allow the localization of pathologically parathyroid glands. Material and methods: The study was conducted in a group of 19 adult patients with severe tHP who were resistant or intolerant to non-invasive treatment, with negative results of scintigraphy and ultrasonography of the neck. The study protocol included measurement of the concentration of calcium, phosphorus, and PTH in the blood serum and performing PET/CT with [¹¹C]MET. Results: A positive result of PET/CT was obtained in 89.5% of the patients (17/19). Parathyroidectomy was performed in 52.9% of the patients (9/17) with positive results of PET/CT with [¹¹C]MET, which were fully consistent with the results of the histopathological examinations of the removed parathyroid glands. On this basis, the sensitivity of PET/CT with [¹¹C]MET in the preoperative localization diagnosis of patients with tHP was found to be 100%. Multiple lesions were visualized in 57.9% of the patients (11/19). Ectopic lesions were visualized in 21.1% of the patients (4/19). Conclusions: PET/CT with [¹¹C]MET is a sensitive technique for the second-line preoperative imaging of parathyroid glands in patients with tertiary hyperparathyroidism in whom first-line examinations, such as ultrasound and scintigraphy, has failed.

Background: Neuroendocrine neoplasms (NENs) are heterogeneous groups of tumours derived from neuroendocrine cells of the ectoderm or endoderm. They are considered rare, with an estimated incidence and prevalence of 6/100,000 and 35/100,000 respectively, and a noticeable upward trend. Radioligand therapy (RLT) using beta-radiation-emitters combined with somatostatin analogues is an effective and relatively safe treatment method. It is usually used as a second-line therapy in case of progressive disease. Material and methods: In retrospective analysis covering eight years of observation (2015–2023) of patients treated in a single highest-reference NEN centre, a subgroup of 13 who received RLT re-treatment (¹⁷⁷Lu or ¹⁷⁷Lu/⁹⁰Y-mixture) was identified. Epidemiological aspects, renal, hepatic, haematological parameters and chromogranin A serum concentration were analysed. Results: The median PFS after the first cycle of RLT was 53.8 months (IQR = 19.3). Directly after the second cycle of RLT disease stabilization and progression was observed in 11/13 (84.6%) and 2/13 (15.4%) patients respectively. After the second cycle of RLT median observation time for the study group was 16.2 months. Eight out of 13 patients were reachable for long-term observation and stabilization was confirmed in 62.5 % (5/8), progression in 12.5% (1/8) and death in 25% (2/8) patients. Median survival time in patients with confirmed death was 7 months. During observation, an increase in creatinine concentration with a decrease in glomerular filtration rate (GFR) was noticed, however, the values were at a statistical trend level (p = 0.056; p = 0.071). The increase of liver parameters was statistically, but not clinically significant. The decrease in albumin concentration and fasting glucose concentration were not significant. An increase in chromogranin A concentration correlated, although not statistically, with the progression of the disease. A statistically significant decrease in the number of all bone marrow cell lines was observed. The first RLT cycle caused a higher decrease in blood parameters than the second. There were no differences in PFS or laboratory parameters depending on the radioligand ([¹⁷⁷Lu]Lu-DOTA-TATE vs. [¹⁷⁷Lu]Lu-DOTA-TATE/[⁹⁰Y]Y-DOTA-TATE). Conclusions: In follow-up after RLT re-treatment stabilization was observed in 62.5%, progression in 12.5% and death in 25% of patients. Decrease of glomerular filtration, and bone marrow parameters resulted from the cumulative adverse effect of RLT, the natural ageing process, and the progression of the disease. Side effects were mainly caused by the first treatment cycle. There was no significant influence on the measured parameters, depending on the radioisotope used. Re-treatment of RLT seems to be a reliable and relatively safe method, thus should be considered in patients who underwent one cycle of RLT and responded to the treatment. Background: Neuroendocrine neoplasms (NENs) are heterogeneous groups of tumours derived from neuroendocrine cells of the ectoderm or endoderm. They are considered rare, with an estimated incidence and prevalence of 6/100,000 and 35/100,000 respectively, and a noticeable upward trend. Radioligand therapy (RLT) using beta-radiation-emitters combined with somatostatin analogues is an effective and relatively safe treatment method. It is usually used as a second-line therapy in case of progressive disease. Material and methods: In retrospective analysis covering eight years of observation (2015–2023) of patients treated in a single highest-reference NEN centre, a subgroup of 13 who received RLT re-treatment (¹⁷⁷Lu or ¹⁷⁷Lu/⁹⁰Y-mixture) was identified. Epidemiological aspects, renal, hepatic, haematological parameters and chromogranin A serum concentration were analysed. Results: The median PFS after the first cycle of RLT was 53.8 months (IQR = 19.3). Directly after the second cycle of RLT disease stabilization and progression was observed in 11/13 (84.6%) and 2/13 (15.4%) patients respectively. After the second cycle of RLT median observation time for the study group was 16.2 months. Eight out of 13 patients were reachable for long-term observation and stabilization was confirmed in 62.5 % (5/8), progression in 12.5% (1/8) and death in 25% (2/8) patients. Median survival time in patients with confirmed death was 7 months. During observation, an increase in creatinine concentration with a decrease in glomerular filtration rate (GFR) was noticed, however, the values were at a statistical trend level (p = 0.056; p = 0.071). The increase of liver parameters was statistically, but not clinically significant. The decrease in albumin concentration and fasting glucose concentration were not significant. An increase in chromogranin A concentration correlated, although not statistically, with the progression of the disease. A statistically significant decrease in the number of all bone marrow cell lines was observed. The first RLT cycle caused a higher decrease in blood parameters than the second. There were no differences in PFS or laboratory parameters depending on the radioligand ([¹⁷⁷Lu]Lu-DOTA-TATE vs. [¹⁷⁷Lu]Lu-DOTA-TATE/[⁹⁰Y]Y-DOTA-TATE). Conclusions: In follow-up after RLT re-treatment stabilization was observed in 62.5%, progression in 12.5% and death in 25% of patients. Decrease of glomerular filtration, and bone marrow parameters resulted from the cumulative adverse effect of RLT, the natural ageing process, and the progression of the disease. Side effects were mainly caused by the first treatment cycle. There was no significant influence on the measured parameters, depending on the radioisotope used. Re-treatment of RLT seems to be a reliable and relatively safe method, thus should be considered in patients who underwent one cycle of RLT and responded to the treatment.

Background: Renal cell carcinoma is one of the most aggressive urogenital malignancies, with an increasing number of cases worldwide. The majority of cases are diagnosed at an advanced stage, as this form of growth is typically silent. An accurate evaluation of the extent of the disease is crucial for selecting the most appropriate treatment approach. Nuclear medicine imaging is increasingly being applied in oncological diagnostics, prompting ongoing research into renal cell carcinoma markers that could serve as a foundation for theranostic approaches in this disease. Positron emission tomography/computed tomography imaging with prostate-specific membrane antigen (PSMA) ligands has already demonstrated successful utility in diagnosis of other cancers, including prostate cancer and gliomas. Emerging evidence of high sensitivity and specificity in detecting renal cell carcinoma lesions provides a suitable foundation for its application in both the diagnosis and subsequent management of this malignancy. Methods: This systematic review synthesizes the current scientific evidence on the molecular imaging of renal cell carcinoma using PSMA ligands, emphasizing the potential future applications of this imaging marker in theranostic approaches. Results and Conclusions: Based on a systematic review of the literature, it appears that PET/CT with PSMA ligands has the potential to surpass traditional imaging techniques in diagnostic accuracy while also providing valuable prognostic information.

The rapid development of nuclear medicine offers vast opportunities for diagnosing neoplasms, particularly in endocrinology. The use of the [¹¹C]C-methionine radiotracer is currently limited due to its physical properties and the complex production process. However, studies conducted so far have demonstrated its utility in PET imaging, helping to detect lesions that often remain elusive with other modalities. This systematic review focuses on [¹¹C]C-methionine in diagnosing hyperparathyroidism and pituitary tumors, highlighting its high effectiveness, which can be crucial in diagnosis. Despite some disadvantages, it should be considered when available, especially when other modalities or radiotracers fail.