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The aim of this study was to perform a systematic review of the prognostic value of texture parameters derived by 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in patients with lung cancer. PubMed and EMBASE databases were searched up to March 12, 2018, for original articles involving texture analysis for the prediction of prognosis in patients with lung cancer. Risk of bias in the studies was critically assessed using the QUIPS tool. The results of survival analysis in the included studies were compared. Of the 446 articles retrieved, 17 studies were eligible for inclusion. Our review suggests that the prognostic value of texture parameters in lung cancer remains unproven. Most studies had a moderate to high risk of bias. Texture parameters that described prognosis were not replicated across studies. Conflicting results on hazard ratios were found among the studies. This discrepancy is partly explained by false-positive findings originating from statistical error and variability caused by different methodologies used for image acquisition and processing in the included studies. Based on currently available evidence, there is insufficient evidence to support the prognostic value of texture analysis in 18F-FDG PET in lung cancer. Further studies implementing well-established methodologies and statistical evidence are warranted for proper validation of these promising imaging biomarkers.

The aim of this study was to perform a systematic review of the prognostic value of texture parameters derived byPubMed and EMBASE databases were searched up to March 12, 2018, for original articles involving texture analysis for the prediction of prognosis in patients with lung cancer. Risk of bias in the studies was critically assessed using the QUIPS tool. The results of survival analysis in the included studies were compared.Of the 446 articles retrieved, 17 studies were eligible for inclusion. Our review suggests that the prognostic value of texture parameters in lung cancer remains unproven. Most studies had a moderate to high risk of bias. Texture parameters that described prognosis were not replicated across studies. Conflicting results on hazard ratios were found among the studies. This discrepancy is partly explained by false-positive findings originating from statistical error and variability caused by different methodologies used for image acquisition and processing in the included studies.Based on currently available evidence, there is insufficient evidence to support the prognostic value of texture analysis in

The purpose of this study was to investigate the diagnostic performance of postoperative fluorine-18 fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) as a surveillance modality for advanced gastric cancer patients who were asymptomatic and negative by conventional follow-up.We retrospectively collected 46 advanced gastric cancer patients who received approximately 1-year-postoperative (18)F-FDG PET/CT surveillance following curative resection (mean age 60.6 ± 11.5 years). (18)F-FDG PET/CT was interpreted by nuclear medicine physicians who were blind to the clinical information. Final confirmation was determined by clinical follow-up using tumor markers, conventional CT scan, upper gastrointestinal endoscopy and with/without subsequent histopathologic diagnosis.Four patients developed recurrence (8.7 %; 1 local and 3 distant recurrences). For local recurrence, (18)F-FDG PET/CT found four hypermetabolic lesions and one was local recurrence. For distant recurrence, seven hypermetabolic lesions were found in six patients and true-positive was three lesions. False-positive cases were mainly turned out to be physiologic small bowel uptake. Regardless of the recurrence site, the sensitivity, specificity, positive predictive value and negative predictive value of (18)F-FDG PET/CT were 100 % (4/4, 95 % confidence interval (CI) 39.6-100 %), 88.1 % (37/42, 95 % CI 73.6-95.5 %), 44.4 % (4/9, 95 % CI 15.3-77.3 %) and 100 % (37/37, 95 % CI 88.3-100 %), respectively in the patient-based analysis.Our study showed good specificity of postoperative surveillance (18)F-FDG PET/CT for detecting recurrence. Careful caution should be made for interpreting some false-positive hypermetabolic lesions in postoperative (18)F-FDG PET/CT, especially at the local anastomosis site.

The present study aimed to investigate the effect of 18F-fluorodeoxyglucose (FDG) extravasation on the time taken for tumoral uptake to reach a plateau. For the animal experiment, FDG extravasation was conducted in the tails of HCT116 tumor-bearing xenograft mice models in three groups (no extravasation, 40 % extravasation, and 80 % extravasation; n = 5, each). Dynamic positron emission tomography (PET) images were acquired over a period of 2 h following injection. Time–activity curves for FDG in the tails and tumors were calculated. For the clinical experiment, 22 patients (male:female, 14:8; age range, 70.8 ± 9.2 years) were subjected to PET/computed tomography (PET/CT) 1 h after the injection of FDG. The inclusion criteria were as follows: (1) submitted to both whole-body and subsequent regional scanning; (2) entire extravasation activity visualized in the whole-body images; (3) tumor visualized on both whole-body and additional regional images; and (4) status of tumor either confirmed by biopsy or clinically suspected for malignancy. The standardized uptake values (SUVs) of the tumors (on the whole-body and additional PET images) and extravasation sites were recorded. There were no significant differences in the time taken for tumoral uptake to reach a plateau and that to reach minimum activity at the extravasation site among the three groups of mice. However, the mean tumoral activity and activity at the extravasation site were negatively correlated at 1 h post-injection. According to the clinical PET findings, the differences in SUV between the whole-body and regional images were not significantly correlated with the interval between injection of FDG and start of whole-body scanning, interval between the start of whole-body scanning and start of regional scanning, extravasation volume, maximum SUV of the extravasation site, or total activity at the extravasation site. The time taken for tumoral uptake to reach a plateau is not affected by extravasation, even at extensive degrees. Thus, in routine practice, the imaging time of approximately 60 min post-injection need not be modified even if extravasation is identified. However, tumor SUV may be underestimated in cases of extravasation.

Metformin-induced [F-18] fluorodeoxyglucose (FDG) bowel uptake can hinder positron emission tomography/computed tomography (PET/CT) evaluation of the bowel. This study aimed to investigate the segmental bowel uptake of FDG according to metformin discontinuation times up to 72 h. We retrospectively divided 240 diabetic patients into four groups: metformin discontinuation

The maximal safe dose (MSD) on the basis of bone marrow irradiation levels allows the delivery of a large amount of I-131 to thyroid cancer tissue. The efficacy of MSD therapy in differentiated metastatic thyroid cancers that persisted after conventional fixed dose therapy is investigated.Forty-seven differentiated thyroid carcinoma patients with non-responsive residual disease despite repetitive fixed dose I-131 therapy were enrolled in this study. Their postoperative pathologies were 43 papillary carcinomas and 4 follicular carcinomas. The MSD was calculated with the Memorial Sloan-Kettering Cancer Center protocol using serial blood samples. The MSDs were administered at intervals of 6 months. Treatment responses were evaluated using I-131 whole-body scans and serum thyroglobulin measurements.The mean calculated MSD was 12.5 +/- 2.1 GBq (339.6 +/- 57.5 mCi). Of the 46 patients, 7 (14.9%) showed complete remission, 15 (31.9%) partial remission, 19 (40.4%) stable disease, and 6 (12.8%) disease progression. Of the patients who showed complete or partial remission, 15 (65%) showed response after the first MSD session and 6 (26%) showed response after the second session. Twenty-nine patients (62%) experienced transient cytopenia after therapy, but three did not recover to the baseline level.The maximal safe dose provides an effective means of treatment in patients who failed to respond adequately to conventional fixed dose therapy. I-131 MSD therapy can be considered in patients who fail fixed dose therapy.

A diffuse hepatic uptake (DHU) on radioiodine whole-body scans (WBS) after (131)I therapy is caused by (131)I-labeled iodoproteins, particularly (131)I-labeled thyroglobulin (Tg). We hypothesized that the DHU intensity after (131)I therapy might correlate with subsequent serum Tg reduction, suggesting that DHU reflects destruction of functioning thyroid tissue as measured by serum Tg.We retrospectively reviewed the medical records and (131)I WBSs of 47 patients treated with (131)I therapy for distant metastasis from differentiated thyroid cancer (M:F = 15:32, median age 45 years, range 11-74 years). All patients received post-ablative (131)I scans (PAWBS) at first (131)I ablation after total thyroidectomy and post-therapy (131)I scan (PTWBS) at second (131)I therapy. The DHU intensities of the PAWBS and PTWBS were classified into 3 grades: 1, faint; 2, modest; and 3, intense. Serum thyroid-stimulating hormone-stimulated Tg (sTg) levels were measured at the time of each therapy and 1 year after the second (131)I therapy.One year after the second (131)I therapy, 10 patients (21.3%) were in remission and 37 (78.7%) had persistent disease. The DHU intensity on PAWBS correlated with the percentage sTg reduction at the next follow-up point (σ = 0.466, p = 0.0016). The patients with intense DHU on PTWBS tended to have a higher percentage sTg reduction than the other patients, although statistical significances were marginal (Spearman's rank correlation: σ = 0.304, p = 0.054; Kruskal-Wallis test: p = 0.067). In univariate analysis, the DHU grades on PAWBS and the initial sTg levels were significantly different between patients in remission and those with persistent disease (PAWBS: p = 0.022; initial sTg: p = 0.0059). In multivariate logistic regression analysis, after adjusting for initial sTg levels, a DHU grade of 3 on PAWBS was an independent predictor of remission (PAWBS: p = 0.028; initial sTg100 ng/ml: p = 0.043).In patients with iodine-avid distant metastases, intensity of DHU on (131)I post-therapy scan correlated with subsequent percentage serum sTg reduction. Also, intense DHU could be one of the predictors of remission in these patients.

Bronchial anthracofibrosis characterized by bronchostenosis associated with anthracotic pigmentation in bronchoscopic finding without a relevant history of pneumoconiosis or smoking has been recently described as a clinical entity. Radiologic finding of bronchial obstructive lesion and mediastinal lymph nodes in bronchial anthracofibrosis can be mimicking cancer. However, the metabolic characteristics of bronchial anthracofibrosis have hardly been reported. Here, we report a case of bronchial anthracofibrosis which showing hypermetabolism on F-18 FDG PET.