Prostate specific membrane antigen (PSMA) ligands for diagnosis and therapy of prostate cancer

<p><b>Introduction:</b> Prostate specific membrane antigen (PSMA) has become an attractive diagnostic and therapeutic target for small molecule ligands. Radionuclide-chelating ligands can be labeled with either ⁶⁸Ga for positron-emission-tomography (PET) or ¹⁷⁷Lu for radionuclide therapy.</p> <p><b>Areas covered:</b> In this literature review we evaluate the diagnostic value of ⁶⁸Ga PSMA PET/CT and the therapeutic potential of ¹⁷⁷Lu PSMA radioligand therapy (RLT) in patients with prostate cancer. ⁶⁸Ga PSMA PET/CT is more accurate than CT for nodal staging and superior to conventional imaging in patients with biochemical recurrence, translating into major changes in clinical management. The preliminary data for ¹⁷⁷Lu PSMA indicates >50% reduction of PSA levels in up to 59% of patients. Severe adverse events occurred <10% of patients after RLT.</p> <p><b>Expert commentary:</b> PSMA ligands for diagnostic and therapeutic purpose will significantly impact the management of patients with prostate cancer.</p

Additional file 1: of Sentinel lymph node excision with or without preoperative hybrid single-photon emission computed tomography/computed tomography (SPECT/CT) in melanoma: study protocol for a multicentric randomized controlled trial

SPIRIT Checklist. The complete SPIRIT checklist regarding the SNEPS trial. (PDF 215 kb

Activation of brown adipose tissue in hypothyroidism

<div><p></p><p><b>Background</b> Brown adipose tissue (BAT) attracts growing interest as a potential therapeutic target for obesity and diabetes. Hyperthyroidism is well-known to increase BAT activity, but the role of hypothyroidism is controversial. We aimed to investigate the association between different thyroid hormone (TH) states and BAT activity.</p><p><b>Methods</b> FDG-PET studies were retrospectively evaluated in thyroid cancer patients after total thyroidectomy both at euthyroidism during TH replacement or at hypothyroidism after TH cessation. Serum TH levels were compared between patients with active BAT and control patients with non-active BAT matched for age, gender, and body mass index. Additionally, animal experiments with controls (<i>n</i> = 5) and hypothyroid rats (<i>n</i> = 5) were performed.</p><p><b>Results</b> Out of 124 patients, 6 patients with active BAT were identified. These patients showed significantly higher thyroid-stimulating hormone (TSH) levels than matched controls (<i>P</i> < 0.05). In animal experiments, all hypothyroid animals showed BAT activation at room temperature (24 °C), whereas controls did not (<i>P</i> < 0.001). Increased BAT activity was also confirmed by increased expression of UCP-1 and D2.</p><p><b>Conclusions</b> Increased BAT metabolism appears to be related with hypothyroidism, which might be the result of a feedback mechanism to maintain body temperature in a state of reduced basal thermogenesis. Future research needs to explore the underlying mechanistic and biological implications.</p><p></p><p>Key Messages</p><p></p><p>Increased brown adipose tissue (BAT) metabolism appears to be related with hypothyroidism, which might be the result of a feedback mechanism to maintain body core temperature in a state of reduced basal thermogenesis.</p><p></p><p></p><p></p></div

Additional file 1 of Treatment-related changes in neuroendocrine tumors as assessed by textural features derived from 68Ga-DOTATOC PET/MRI with simultaneous acquisition of apparent diffusion coefficient

Additional file 1: Figure S1. Axial ADC maps (a + c) and PET (b + d) of 21 years-old patient with G3 NET of the pancreas and disease progression under chemotherapy. Interval between baseline (a + b) and follow-up (c + d) is 5 months

Additional file 2 of Treatment-related changes in neuroendocrine tumors as assessed by textural features derived from 68Ga-DOTATOC PET/MRI with simultaneous acquisition of apparent diffusion coefficient

Additional file 2: Figure S2. Axial ADC maps (a + c) and PET (b + d) of 64 years-old patient with G2 NET of the pancreas showing response to treatment with long-acting somatostatin analogues. Interval between baseline (a + b) and follow-up (c + d) is 12 months

Patient data, antibodies, clinical findings.

Patient data, antibodies, clinical findings.</p

Results of whole-body PET/MRI.

Results of whole-body PET/MRI.</p

Images of a 58-year-old patient with recurrence of ovarian cancer.

<p>CT image (A) shows a peritoneal mass next to the liver with pathological FDG metabolism in fused PET/CT images (B). The same lesion is visible in post-contrast media VIBE sequence in MRI (C) and in PET/MRI (D). No FDG metabolism can be seen in a benign liver cyst in PET/CT or PET/MRI (A-D).</p

Comparison of ⁶⁸Ga-DOTATATE uptake and MR contrast agent enhancement.

<p>In all 3 patients, there is a marked overlap between ⁶⁸Ga-DOTATATE uptake and MR contrast agent enhancement. Radiotracer accumulation is most pronounced in areas with intense contrast enhancement. Shown are axial views of contrast-enhanced T1-weighted MR as well as fused MR/PET images.</p

Distribution of benign and malignant lesions.

<p>Distribution of benign and malignant lesions.</p