Gastroenteropancreatic Neuroendocrine Tumors: Standardizing Therapy Monitoring with Ga-DOTATOC PET/CT Using the Example of Somatostatin Receptor Radionuclide Therapy

The purpose of this study was to standardize therapy monitoring of hepatic metastases from gastroenteropancreatic neuroendocrine tumors (GEP-NETs) during the course of somatostatin receptor radionuclide therapy (SRRT). In 21 consecutive patients with nonresectable hepatic metastases of GEP-NETs, chromogranin A (CgA) and 68 Ga-DOTATOC PET/CT were compared before and after the last SRRT. On 68 Ga-DOTATOC PET/CT, the maximum standard uptake values (SUV max ) of normal liver and hepatic metastases were calculated. In addition, the volumes of hepatic metastases (volume of interest [VOI]) were measured using four cut-offs to separate normal liver tissue from metastases (SUV max of the normal liver plus 10% [VOI liver+10% ], 20% [VOI liver+20% ], 30% [VOI liver+30% ] and SUV = 10 [VOI 10SUV ]). The SUV max of the normal liver was below 10 (7.2 ± 1.3) in all patients and without significant changes. Overall therapy changes (Δ) per patient (mean [95% CI]) were statistically significant with p < .01 for ΔCgA = −43 (−69 to −17), ΔSUV max = −22 (−29 to −14), and ΔVOI 10SUV = −53 (−68 to −38)% and significant with p < .05 for ΔVOI liver+10% = −29 (−55 to −3)%, ΔVOI liver+20% = −32 (−62 to −2) and ΔVOI liver+30% = −37 (−66 to −8). Correlations were found only between ΔCgA and ΔVOI 10SUV ( r = .595; p < .01), ΔSUV max and ΔVOI 10SUV (0.629, p < .01), and SUV max and ΔSUV max ( r = .446; p < .05). 68 Ga-DOTATOC PET/CT allows volumetric therapy monitoring via an SUV-based cut-off separating hepatic metastases from normal liver tissue (10 SUV recommended)

Prostate carcinoma: diffusion-weighted imaging as potential alternative to conventional MR and 11C-choline PET/CT for detection of bone metastases

In a technical development study approved by the institutional ethics committee, the feasibility of fast diffusion-weighted imaging as a replacement for conventional magnetic resonance (MR) imaging sequences (short inversion time inversion recovery [STIR] and T1-weighted spin echo [SE]) and positron emission tomography (PET)/computed tomography (CT) in the detection of skeletal metastases from prostate cancer was evaluated. MR imaging and carbon 11 ((11)C) choline PET/CT data from 11 consecutive prostate cancer patients with bone metastases were analyzed. Diffusion-weighted imaging appears to be equal, if not superior, to STIR and T1-weighted SE sequences and equally as effective as (11)C-choline PET/CT in detection of bone metastases in these patients. Diffusion-weighted imaging should be considered for further evaluation and comparisons with PET/CT for comprehensive whole-body staging and restaging in prostate and other cancers

Chondral lesions in the patellofemoral joint in MRI: Intra-individual comparison of short-tau inversion recovery sequence (STIR) with 2D multiple-echo data image combination sequence (MEDIC)

Purpose: To determine the value of the 2D multiple-echo data image combination (MEDIC) sequence relative to the short-tau inversion recovery (STIR) sequence regarding the depiction of chondral lesions in the patellofemoral joint. Materials and methods: During a period of 6 month patients with acute pain at the anterior aspect of the knee, joint effusion and suspected chondral lesion defect in the patellofemoral joint underwent MRI including axial MEDIC and STIR imaging. Patients with chondral lesions in the patellofemoral joint on at least one sequence were included. The MEDIC and STIR sequence were quantitatively compared regarding the patella cartilage-to-effusion contrast-to-noise ratio (CNR) and qualitatively regarding the depiction of chondral lesions independently scored by two radiologists on a 3-point scale (1 = not depicted; 2 = blurred depicted; 3 = clearly depicted) using the Wilcoxon-Mann-Whitney-Test. For the analysis of inter-observer agreement the Cohen's Weighted Kappa test was used. Results: 30 of 58 patients (male: female, 21:9; age: 44 ± 12 yrs) revealed cartilage lesions (fissures, n = 5 including fibrillation; gaps, n = 15; delamination, n = 7; osteoarthritis, n = 3) and were included in this study. The STIR-sequence was significantly (p < 0.001) superior to the MEDIC-sequence regarding both, the patella cartilage-to-effusion CNR (mean CNR: 232 ± 61 vs. 40 ± 16) as well as the depiction of chondral lesion (mean score: 2.83 ± 0.4 vs. 1.75 ± 0.7) with substantial inter-observer agreement in the rating of both sequences (κ = 0.76–0.89). Conclusion: For the depiction of chondral lesions in the patellofemoral joint, the axial STIR-sequence should be chosen in preference to the axial MEDIC-sequence. Keywords: MRI, Chondral Lesion, Patellofemoral Joint, STIR, MEDI

MOESM1 of Focal colorectal uptake in 18FDG-PET/CT: maximum standard uptake value as a trigger in a semi-automated screening setting

Additional file 1: Table S1. Demographic Data of Patients with Colorectal Cancer (n=54)