Comparison of 18F-FDG PET/CT and MDCT for staging/restaging of non-small cell lung cancer.

UNLABELLED: Multi-detector computed tomography (MDCT) is most commonly used for staging of non-small cell lung cancer (NSCLC). In recent years, 18F- fluorodeoxyglucose positron emission tomography combined with computed tomography (18F-FDG PET/CT) has also been used for the same purpose. Since studies comparing these two methods are scarce, our aim was to determine how the TNM classification and thereby staging of NSCLC compare between 18F-FDG PET/CT and MDCT. 18F-FDG PET/CT and MDCT were collected in 83 patients with NSCLC 3 to 30 days apart (median 17 days). The investigators interpreting 18F-FDG PET/CT were unaware of MDCT results. The Cohen's kappa (κ) was calculated to determine the rate of agreement. The hypothesis was that the strength of agreement between the two methods will be at least moderate (κ>0.40) based on the adopted criteria (κ<0.20 poor; 0.21-0.40 fair; 0.41-0.60 moderate; 0.61-0.80 good; 0.81-1.00 very good agreement). The agreement was moderate for determining the T class (κ=0.45, overall agreement 58%), poor for the N class (κ=0.13, 42%) and fair for the M class (κ=0.22, 58%). The agreement for overall staging of NSCLC was poor (κ=0.20, 45%). The major source of disagreement was that metastases were present more frequently and/or in larger number on 18F-FDG PET/CT than MDCT in the contralateral mediastinal, supraclavicular, and distant lymph nodes, as well as in the bones and suprarenal glands. Since 18F-FDG PET/CT detected more regional and distant metastases than MDCT, we conclude that FDG PET/CT is useful for staging/restaging and planning treatment of patients with NSCLC. KEYWORDS: Non-small cell lung cancer, positron emission tomography, multidetector computed tomography, metastases detection.

The utility of 99mTc-EDDA/HYNIC-TOC scintigraphy for assessment of lung lesions in patients with neuroendocrine tumors.

UNLABELLED: Our aim was to assess clinical utility of 99mTc-EDDA/HYNIC-TOC scintigraphy for evaluation of lung lesions in patients with neuroendocrine tumors (NETs). Single photon emission computed tomography (SPECT) of the thorax and whole body scintigraphy were performed in 34 patients using 99mTc-EDDA/HYNIC-TOC. Visual assessment was complemented by semiquantitative evaluation based on tumor to non-tumor (T/NT) ratio. Clinical, laboratory, and histological findings served as the standard for comparison. Enhanced tracer uptake was observed on both SPECT and whole body scintigraphy in 29 of 34 patients (88% sensitivity). T/NT ratios were significantly higher on SPECT than whole body images (2.96+/-1.07 vs.1.70+/-0.43, p KEYWORDS: 99mTc-EDDA/Hynic-TOC, lung involvement of NETs, T/NT ratio.

Diagnostic approach to reflex sympathetic dystrophy after fracture: radiography or bone scintigraphy?

The aim of this paper was to compare the value of bone scintigraphy and radiography in the early diagnosis of post-fracture reflex sympathetic dystrophy (RSD). Thirty-seven adult patients with post-fracture RSD (28 in the first and nine in the second clinical stage of RSD), as well as seven patients with fracture but without RSD (control group), were investigated by radiography and bone scintigraphy. All of them were immobilized (duration of immobilization: 4-22 weeks). In 21 persons three phase bone scintigraphy was performed. The best distinction between the control group and the RSD patients was achieved by delayed bone scintigrams. The sensitivity (97%), positive predictive value (97%) and accuracy (95%) of delayed bone scintigraphy were very high compared to the values for radiography, which were 73%, 90% and 70% respectively. Bone scintigraphy also displayed higher specificity (86%) and negative predictive value (86%) than radiography (57% and 29% respectively). In the first clinical stage the difference between the accuracy of bone scintigraphy (97%) and radiography (63%) was greater than for the whole group. In the second stage of RSD the accuracy of bone scintigraphy (86%) and radiography (81%) was similar. Three-phase bone scintigraphy is not necessary for the diagnosis of post-fracture RSD: it is sufficient to perform delayed bone scintigraphy. It is concluded that bone scintigraphy is to be preferred to radiography for the early diagnosis of post-fracture RSD in the first clinical stage. In the second stage the diagnostic capabilities of bone scintigraphy and radiography are more comparable.

Determining the lifespan of platelets labelled with 111In oxinate--first results.

The paper presents the new method of platelet labelling, quality control of separation and labelling, as well as the investigation of the 111In oxinate labelled platelets lifespan. Among the 23 investigated persons, there were 4 hematologically healthy persons and 19 ITP patients. Homologous and autologous labellings were done in one and 22 persons, respectively. Determination of the platelet lifespan in healthy subjects enabled the estimation of "in vitro" procedures of separation and labelling, as well as "in vivo" behaviour of the labelled platelets. Our results show that 111In oxinate labelled platelets have normal lifespan (8.9 +/- 0.6 days), which means that the procedure of separation and labelling does not damage them. In the ITP patients the platelet lifespan is shortened (0.4-4.6 days), which confirms the mechanism of thrombocytopenia. In the subject where homologous labelling had been done, we found out the existence of sensibilisation toward the donor platelets, which lead to the correction of therapy.