Relationship between 18F-FDG PET/CT Semi-Quantitative Parameters and International Association for the Study of Lung Cancer, American Thoracic Society/European Respiratory Society Classification in Lung Adenocarcinomas.

OBJECTIVE: To investigate the relationship between 18F-FDG PET/CT semi-quantitative parameters and the International Association for the Study of Lung Cancer, American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) histopathologic classification, including histological subtypes, proliferation activity, and somatic mutations. MATERIALS AND METHODS: This retrospective study included 419 patients (150 males, 269 females; median age, 59.0 years; age range, 23.0-84.0 years) who had undergone surgical removal of stage IA-IIIA lung adenocarcinoma and had preoperative PET/CT data of lung tumors. The maximum standardized uptake values (SUVmax), background-subtracted volume (BSV), and background-subtracted lesion activity (BSL) derived from PET/CT were measured. The IASLC/ATS/ERS subtypes, Ki67 score, and epidermal growth factor/anaplastic lymphoma kinase (EGFR/ALK) mutation status were evaluated. The PET/CT semi-quantitative parameters were compared between the tumor subtypes using the Mann-Whitney U test or the Kruskal-Wallis test. The optimum cutoff values of the PET/CT semi-quantitative parameters for distinguishing the IASLC/ATS/ERS subtypes were calculated using receiver operating characteristic curve analysis. The correlation between the PET/CT semi-quantitative parameters and pathological parameters was analyzed using Spearman's correlation. Statistical significance was set at p < 0.05. RESULTS: SUVmax, BSV, and BSL values were significantly higher in invasive adenocarcinoma (IA) than in minimally IA (MIA), and the values were higher in MIA than in adenocarcinoma in situ (AIS) (all p < 0.05). Remarkably, an SUVmax of 0.90 and a BSL of 3.62 were shown to be the optimal cutoff values for differentiating MIA from AIS, manifesting as pure ground-glass nodules with 100% sensitivity and specificity. Metabolic-volumetric parameters (BSV and BSL) were better potential independent factors than metabolic parameters (SUVmax) in differentiating growth patterns. SUVmax and BSL, rather than BSV, were strongly or moderately correlated with Ki67 in most subtypes, except for the micropapillary and solid predominant groups. PET/CT parameters were not correlated with EGFR/ALK mutation status. CONCLUSION: As noninvasive surrogates, preoperative PET/CT semi-quantitative parameters could imply IASLC/ATS/ERS subtypes and Ki67 index and thus may contribute to improved management of precise surgery and postoperative adjuvant therapy.

Degeneration in the Zygapophysial Joint of the Fifth Lumbar Vertebra: The V-Shaped Sign Revealed by Bone Scintigraphy.

OBJECTIVE: The aim of the study was to explore the nature of a V-shaped sign in the backbone of the fifth lumbar vertebra revealed by whole-body bone scintigraphy (WBBS). METHODS: A local single-photon emission computed tomography (SPECT) scan plus a computed tomography (CT) scan were performed on 41 patients in our department who had a V-shaped sign in the backbone of the fifth lumbar vertebra detected by WBBS. Image fusion was conducted to understand the manifestations of the changes in the V-shaped sign in the CT images in WBBS and to determine the nature of the lesion. RESULTS: All 41 patients presented with degenerative changes observed in the bilateral posterior zygapophysial joint of the fifth lumbar vertebra in the CT imaging bone window, bone hyperplasia of the articular process, joint surface hardening, and a joint gap. The vacuum sign could also be seen in some of these patients. CONCLUSION: The typical V-shaped sign in the posterior zygapophysial joint of the fifth lumbar vertebra revealed by WBBS suggests degenerative changes in the zygapophysial joint of the fifth lumbar vertebra.

Baseline Total Metabolic Tumor Volume and Total Lesion Glycolysis Measured on 18F-FDG PET-CT Predict Outcomes in T-Cell Lymphoblastic Lymphoma.

PURPOSE: There is no optimal prognostic model for T-cell lymphoblastic lymphoma (T-LBL). Here, we discussed the predictive value of total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) measured on 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in T-LBL. MATERIALS AND METHODS: Thirty-seven treatment naïve T-LBL patients with PET-CT scans were enrolled. TMTV was obtained using the 41% maximum standardized uptake value (SUVmax) threshold method, and TLG was measured as metabolic tumor volume multiplied by the mean SUV. Progression-free survival (PFS) and overall survival (OS) were analyzed by Kaplan-Meier curves and compared by the log-rank test. RESULTS: The optimal cutoff values for SUVmax, TMTV, and TLG were 12.7, 302 cm3, and 890, respectively. A high SUVmax, TMTV, and TLG indicated a shorten PFS and OS. On multivariable analysis, TMTV ≥ 302 cm3, and central nervous system (CNS) involvement predicted inferior PFS, while high SUVmax, TLG and CNS involvement were associated with worse OS. Subsequently, we generated a risk model comprising high SUVmax, TMTV or TLG and CNS involvement, which stratified the population into three risk groups, which had significantly different median PFS of not reached, 14 months, and 7 months for low-risk group, mediate-risk group, and high-risk group, respectively (p < 0.001). Median OS were not reached, 27 months, and 13 months, respectively (p < 0.001). CONCLUSION: Baseline SUVmax, TMTV, and TLG measured on PET-CT are strong predictors of worse outcome in T-LBL. A risk model integrating these three parameters with CNS involvement identifies patients at high risk of disease progression.

Research on the midterm efficacy and prognosis of patients with diffuse large B-cell lymphoma by different evaluation methods in interim PET/CT.

PURPOSE: To investigate the midterm efficacy and prognostic evaluation of patients with diffuse large B-cell lymphoma (DLBCL) by three image analysis methods: International Harmonization Project (IHP), Deauville 5-Point Scale (5-PS) and Δ SUVmax criteria in 18F-FDG PET/CT. METHODS: This was a retrospective analysis of 141 patients with DLBCL. All patients were given 3-4 cycles of chemotherapy and 18F-FDG PET/CT. According to three criteria, the patients were divided into negative and positive groups, respectively. Statistical methods were used to assess the midterm efficacy and prognosis factors. RESULTS: During the midterm follow-up, a total of 109 people achieved CR. Three methods showed statistically significant differences in OS and PFS for the interim PET/CT, and Δ SUVmax criterion was an independent risk factor for the prognosis of DLBCL patients. CONCLUSION: In our research, IHP, 5-PS and Δ SUVmax criteria all had a significant predictive value, while Δ SUVmax criterion had more advantages in evaluating the midterm efficacy and predicting prognosis for patients with DLBCL in interim PET/CT. But it should be noticed that Δ SUVmax criterion needs more strict guidelines in multicenter trials. The optimal cutoff value of Δ SUVmax% we recommended was 81.54%, which helped to judge the midterm efficacy.

The additional value of SPECT/CT fusion imaging in the diagnosis of ectopic gastric mucosa.

OBJECTIVE: To evaluate the value of single-photon emission computed tomography/computed tomography fusion alone and in addition to pertechnetate planar imaging in the diagnosis of ectopic gastric mucosa. METHODS: The retrospective study was conducted at the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China, and comprised medical records from May 2014 to April 2015 of children aged <14 years and suspected of ectopic gastric mucosa. All patients underwent both planar imaging and single-photon emission computed tomography/computed tomography fusion imaging, and were followed up for more than 6 months. The final diagnoses were determined based on the results of pathology and clinical follow-up. The sensitivity, specificity, and accuracy of diagnosing ectopic gastric mucosa were compared by using planar imaging, SPECT/CT fusion imaging and a combination of both. Data was analysed using SPSS 21. RESULTS: Of the 41 patients, ectopic gastric mucosa was diagnosed in 24(58.5%) by pathological results or clinical follow-up. Planar imaging suggested 33(80.5%) positive and 8(19.5%) negative cases, while fusion imaging reported 23(56%) and 18(44%) respectively. The sensitivity, specificity and accuracy of planar imaging were 91.67%? 35.29% and 68.29%, and in fusion imaging they were 91.67%?94.12% and 89.47% respectively. The corresponding values of the combination of two imaging techniques were 91.67%?100% and 95.12% respectively (p=0.006). Kappa value of the diagnostic consistency between fusion imaging and a combination of two imagings was 0.951 (p=0.0001). CONCLUSIONS: Planar imaging had a low specificity compared to fusion imaging and a combination of fusion and planar imagings.

18 F-FDG PET/CT imaging of small intestinal metastasis from pulmonary sarcomatoid carcinoma: Brief report and review of the literature.

We herein report two cases of small intestinal metastasis from pulmonary sarcomatoid carcinoma (PSC) detected by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT). We reviewed the literature on 18 F-FDG PET/CT features in gastrointestinal metastasis of PSC patients since 1992, and further analyzed the imaging features. According to the literature review, 23 eligible cases were identified from eight studies, and no cases underwent 18 F-FDG PET/CT imaging. In this study, clinical and PET/CT imaging data of two patients are reported. In our cases, clinical and the CT images of lung masses were not typical, but the uptake of 18 F-FDG was remarkably high, with SUVmax exceeding 30. Small intestinal metastases may not be related to obstruction, or even the local intestinal cavity may be dilated. Therefore, in PSC patients with mild or without abdominal symptoms, 18 F-FDG PET/CT imaging could identify intestinal metastasis at a relatively early stage and may be used to determine the preferred biopsy site, or early intervention by surgery. KEY POINTS: 18 F-FDG PET/CT imaging of small intestinal metastasis of PSC has not been previously reported in the literature and here we report the 18 F-FDG PET/CT features of two cases. The uptake of 18 F-FDG was remarkably high in both the primary tumor and metastatic intestinal lesion. 18 F-FDG PET/CT imaging may therefore be used to determine the preferred biopsy site or early intervention by surgery.

Utility of baseline, interim and end-of-treatment 18F-FDG PET/CT in extranodal natural killer/T-cell lymphoma patients treated with L-asparaginase/pegaspargase.

Positron emission tomography-computed tomography (PET/CT) is widely used for initial staging and monitoring treatment responses in Hodgkin and diffuse large B-cell lymphoma. However, its prognostic value in extranodal natural killer (NK)/T-cell lymphoma (ENKL) remains unclear. Here, we conducted a retrospective study to determine the impact of PET/CT in ENKL. Fifty-two patients newly diagnosed with ENKL were enrolled. Baseline maximum standardized uptake values (SUVmax), whole-body metabolic tumor volume (WBMTV) and whole-body total lesion glycolysis (WBTLG) were recorded. Additionally, interim PET/CT (I-PET) and end-of-treatment PET/CT (E-PET) results were scored using a 5-point scale. Patients were divided into groups using baseline parameter cut-off values; significant differences were found in overall survival (OS) and progression-free survival (PFS) between the high and low WBMTV and WBTLG groups and in OS between the two SUVmax groups. Positive I-PET and E-PET results predicted inferior PFS and OS. A multivariate analysis showed that baseline WBTLG, I-PET and E-PET results were associated with PFS and OS, and baseline SUVmax was an independent predictor of OS. Thus, baseline WBTLG, I-PET and E-PET results are good predictors of PFS and OS in ENKL patients who received L-asparaginase/pegaspargase in their first-line treatment, and baseline SUVmax is a valuable tool for assessing OS.

A case of abdominal mesenteric Castleman's disease with left renal cell carcinoma and stomach leiomyoma.

A rare case of abdominal mesenteric Castleman's disease with left renal cell carcinoma and stomach leiomyoma is reported. A 57 years old male patient was transferred to our hospital for investigation of a left kidney tumor. Physical examination and routine laboratory tests were normal. Multi mode imaging by 64-slices spiral computed tomography (CT) scan, the enhanced CT scan and the fluorine-18-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) scan were applied. Computed tomography showed a 5.4cm×5.2cm mass in the abdomen. The radioactive distribution of the mass was high SUVmax about 4.5. Furthemore, a soft tissue mass, about 3.9cm×3.0cm, was detected in the left kidney, with significantly inhomogeneous enhancement in the arterial phase of the CT scan, while contrast agent CT showed activity in the venous phase. The radioactive distribution of this mass was slightly concentrated and its SUVmax was about 3.2. With the stomach filled with water , an oval shaped and slightly lobulated soft tissue mass was also observed in the cardia, with a size about 4.6cm×3.0cm. Computed tomography showed mild enhancement of radioactively in the arterial phase and delayed enhancement in the venous phase. The radioactive distribution of the mass was diffused and SUVmax was about 4.7. CONCLUSION: The patient was operated and pathology showed: a) A mesenteric mass and abdominal lymph nodes with cells of the hyaline vascular type of Castleman's disease. b) Renal clear cells carcinoma of the left kidney and c) Spindle cells leiomyoma tumor in the gastric cardia. Three tumors in the same patient are extremely rare.

Findings of multiple neuritis on FDG PET/CT imaging.

A 56-year-old woman with weight loss, facial pain, and weakness underwent FDG PET/CT to detect a tumor of unknown origin. The images did not detect any lesion typical of malignancy. However, elevated FDG activity in several cranial and peripheral nerves was noted and suggestive of multiple neuritis. Following therapy for neuritis, the patient's symptoms improved.

The half maximum time of (99m)Tc-DTPA renography measured in healthy kidney donors, compared to (131)I-OIH.

Technetium-99m-diethylene triamine pentaacetic acid ((99m)Tc-DTPA) has been widely used after (131)I-ortho-hippurate ((131)I-OIH) for renography and to test renal function. Only a few reports refer to normal values range of (99m)Tc-DTPA renography half maximum time (HMT). We have measured the normal value range of (99m)Tc-DTPA renography HMT in our department, of 433 healthy kidney donors from 2007 to 2010, and compared these results with those of (131)I-OIH renography. There were 326 men and 107 women, 18y-69y (median age 29y), subjects were measured before the donation of their kidneys operation and their biochemical, ultrasound and renal function tests were normal. All subjects drunk at least 1 litre of tap water before renography. The (99m)Tc-DTPA dynamic scintigraphy was performed in the posterior view by injecting intravenously as a bolus 185-296MBq. Dynamic imaging was performed immediately after the injection, using a high-resolution low-energy general purpose collimator and a large field of view dual-detector gamma-camera (Hawkeye; General Electric Medical Systems, USA). Matrix was 64Χ64, the phase acquisition time of blood perfusion was 1s/frame and 30 frames were collected. Dynamic acquisition was 30s/frame and 39 frames were collected. Total acquisition time was 20min. We defined as background two regions of interest around the kidneys and the aorta, for radioactive decay correction. We also compared (99m)Tc-DTPA renography HMT values with the HMT values of (131)I-OIH, between the two kidneys, and between men and women. The findings were evaluated by using frequency distribution analysis, paired Sample Student's t-test and one sample t test, with a level of significance P<0.05. We used the SPSS 10.0 statistical software. Since values beyond a high boundary were regarded as unusual, we used the P(95), i.e. " 95% of HMT reference ranges value" to determine the medical reference range of values, as the HMT normal limit. This reference value is used especially when the data shows a skewed distribution. For the HMT (P(95) value), the normal reference values found between mean values of the left and the right kidney were: 10.76±4.14min and 10.89±4.55min, respectively and P=0.416, two tailed. For the left kidney HMT, there was no significant difference between men: 10.90±4.31min and women: 10.33±3.57min, (t=1.235, v=432, P=0.2186, two tailed), and similar findings were found between men's right kidney HMT: 11.02±4.89min and women's right kidney HMT: 10.49±3.32min, (t=1.253, v=266.59, P=0.211, two tailed). By comparing the mean value of (99m)Tc-DTPA renography HMT measured (10.76min, 10.89min) with the mean value of (131)I renography HMT that we found in the literature as referring to both left and right kidneys (4min). We found a significant difference (P=0.000, two tailed). Renography may be used to diagnose urinary tract obstruction, estimate the split renal function and is useful.