Clinical and imaging features preoperative evaluation of histological grade and microvascular infiltration of hepatocellular carcinoma.

BACKGROUND: To predict the histological grade and microvascular invasion (MVI) in patients with HCC. METHODS: A retrospective analysis was conducted on 175 patients who underwent MRI enhancement scanning (from September 2016.9 to October 2020). They were divided into MVI positive, MVI negative, Grade-high and Grade-low groups. RESULTS: The AFP of 175 HCC patients distributed in MVI positive and negative groups, Grade-low and Grade-high groups were statistically significant (P = 0.002 and 0.03, respectively). Multiple HCC lesions were more common in MVI positive and Grade-high groups. Correspondingly, more single lesions were found in MVI negative and Grade-low groups (P = 0.005 and 0.019, respectively). Capsule on MRI was more common in MVI negative and Grade-high groups, and the difference was statistically significant (P = 0.02 and 0.011, respectively). There were statistical differences in the distribution of three MRI signs: artistic rim enhancement, artistic peripheral enhancement, and tumor margin between MVI positive and MVI negative groups (P = 0.001, < 0.001, and < 0.001, respectively). Tumor hypointensity on HBP was significantly different between MVI positive and negative groups (P < 0.001). CONCLUSIONS: Our research shows that preoperative enhanced imaging can be used to predict MVI and tumor differentiation grade of HCC. The prognosis of MVI-negative group was better than that of MVI-positive group.

18F-FDGPET/CT in fever of unknown origin and inflammation of unknown origin: a Chinese multi-center study.

PURPOSE: To evaluate the clinical value of 18F-FDG-PET/CT for the diagnosis of fever of unknown origin (FUO) and inflammation of unknown origin (IUO) in Chinese population, as well as the characteristics of PET/CT in different category of etiological disease. METHODS: A total of 376 consecutive patients with FUO/IUO who underwent FDG-PET/CT at 12 hospitals were retrospectively studied. FDG uptake was quantitatively and visually evaluated, by using SUVmax and a 4-grade scale respectively. A questionnaire survey to the clinicians was used to evaluate the significance of PET/CT in diagnosing of FUO/IUO. Data analysis included the etiological distribution in the study population, image characteristics in different category of diseases, and clinical significance of PET/CT. RESULTS: In 376 studied patients, the infectious diseases accounted for 33.0% of patients, rheumatologic diseases for 32.4%, malignancies for 19.1%, miscellaneous causes for 6.6%, and cause unknown for 8.8%. However, the etiological distribution among hospitals was varied. In addition, the etiological disease composition ratio has changed over time in China. On PET/CT examinations, 358 (95.2%) of the patients had a positive finding. Within them, local high uptake lesion was found in 219 cases, and nonspecific abnormal uptake (NAU) was found in 187 cases. FDG uptake in malignant diseases was significantly higher than in other category diseases both on SUVmax and visual scores (t-value range from 4.098 to 5.612, all P value < 0.001). Based on a clinical questionnaire survey, PET/CT provided additional diagnostic information for 77.4% of patients, and 89.6% of patients benefited from PET/CT examination. CONCLUSIONS: FDG PET/CT is a valuable tool for clinical diagnosis of FUO/IUO, and it is of great significance in further investigating the usefulness of PET/CT in non-neoplastic diseases.

Imaging the expression of glypican-3 in hepatocellular carcinoma by PET.

The glypican-3 (GPC3) receptor is overexpressed in hepatocellular carcinoma (HCC) and is a potential diagnostic and therapeutic target. GPC3-targeted molecular imaging will be helpful to differentiate diagnosis and guide therapy. In the present study, we will develop a novel PET probe for imaging the expression of GPC-3. L5 (sequence: RLNVGGTYFLTTRQ), a GPC3 targeting peptide, was labeled with 5-carboxyfluorescein (FAM) and 18F-fluoride. Cell binding tests were performed to identify the binding specificity of FAM-L5 and 18F radiolabeled peptide. MicroPET/CT imaging was used to determine the potential of a novel PET tracer for visualizing HCC tumors with a high expression of GPC3. In vitro binding tests showed that the uptake of FAM-L5 in HepG2 cells (high expression of GPC3) was significantly higher than that of HL-7702 cells (negative expression of GPC3) (mean fluorescent intensity: 14,094 ± 797 vs. 2765 ± 314 events, t = 32.363, P = 0.000). Confocal fluorescent imaging identified that FAM-L5 accumulated where the GPC3 receptor was located. A novel PET tracer (18F-AlF-NODA-MP-6-Aoc-L5) was successfully labeled by chelation chemistry. In vitro cell uptake studies showed that 18F-AlF-NODA-MP-6-Aoc-L5 can bind to HepG2 tumor cells and was stable in PBS and mouse serum stability tests. MicroPET/CT showed that HepG2 tumors could be clearly visualized with a tumor/muscle ratio of 2.46 ± 0.53. However, the tumor/liver ratio was low (0.93 ± 0.16) due to the high physiological uptake in the liver. This study demonstrates that FAM and the 18F-labeled L5 peptide can selectively target HCC with a high expression of GPC3 in vitro and in vivo. 18F-AlF-NODA-MP-C6-L5 has the potential to be a GPC3 target tracer but requires some chemical modifications to achieve a high enough tumor/liver ratio for detection of the tumor in the liver.

CKD-EPI creatinine-cystatin C glomerular filtration rate estimation equation seems more suitable for Chinese patients with chronic kidney disease than other equations.

BACKGROUND: The aim of this study was to identify the optimal equation that accurately estimates the glomerular filtration rate (GFR) and the chronic kidney disease (CKD) stage in the Chinese population. METHODS: A total of 1296 Chinese patients aged 18-65 years old were enrolled in this study. The estimated GFRs (eGFRs) calculated separately by three Diet in Renal Disease (MDRD) equations and three Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations were compared with the reference GFR (rGFR) measured by the 99Tcm-DTPA renal dynamic imaging method. RESULTS: By Bland-Altman analysis, eGFRcys and eGFRscr_cys performed similarly, showing the tightest limits of agreement among the six equations. They also achieved the first and second highest 30% and 50% accuracies. Using a combination of the serum creatinine and cystatin C levels (eGFRscr_cys) could improve the bias (-0.3 for eGFRscr_cys) of the equation and achieve the highest diagnostic accuracy for renal insufficiency (AUC60, 0.953; P < 0.05, except for eGFR_MDRD). All equations predicted stage 3 CKD with moderate accuracy (49.7-51.4%) and stage 5 CKD with good accuracy (90.2-96.4%). For stage 1 CKD, eGFRcys showed a higher percentage of misclassification than the other equations. All equations seemed to perform poorly at predicting stage 2 and 4 CKD, as compared to the other CKD stages. eGFRscr_cys was the best-performing equation in terms of accurate classification of the CKD stage based on the overall performance (kappa value, 0.423). CONCLUSION: For a Chinese population, the CKD-EPIscr_cys equation seems more suitable for estimating the GFR than the other equations. Each equation had its own advantages in predicting different CKD stages.

18F-FDG PET/CT in differentiating malignant from benign origins of obstructive jaundice.

BACKGROUND: The various origins of obstructive jaundice make the diagnosis of the disease difficult. This study was undertaken to evaluate the role of 18F-FDG PET/CT in differentiating malignant from benign origins of obstructive jaundice and to quantify the added value of 18F-FDG PET/CT over conventional imaging (enhanced CT and/or MRI). METHODS: Eighty-five patients with obstructive jaundice who underwent 18F-FDG PET/CT within 2 weeks after enhanced CT and/or MRI were reviewed retrospectively. All 18F-FDG PET/CT images were independently evaluated by 2 nuclear medicine physicians who were unaware of other imaging data; differences were resolved by consensus of the physicians. All conventional imaging interpretations, according to the medical records, were reviewed by 2 radiologists to determine the potential value. Final diagnoses were based on histological or surgical findings. RESULTS: Sixty-six patients were diagnosed with malignancies, and 19 patients with benign lesions. The maximum standardized uptake values for malignant and benign lesions causing biliary obstruction were 8.2+/-4.4 and 4.0+/-5.0, respectively (P<0.05). The sensitivity, specificity, and overall accuracy for differentiating malignant from benign origins with 18F-FDG PET/CT were 86.4% (57/66), 73.7% (14/19), and 83.5% (71/85), respectively. 18F-FDG PET/CT in conjunction with conventional imaging changed the sensitivity, specificity, and overall accuracy of conventional imaging alone from 75.8% (50/66) to 95.5% (63/66) (P<0.05), 68.4% (13/19) to 57.9% (11/19) (P>0.05), and 74.1% (63/85) to 87.1% (74/85) (P<0.05), respectively. CONCLUSIONS: 18F-FDG PET/CT is of great value in differentiating malignant from benign origins of obstructive jaundice and is a useful adjuvant to conventional imaging. 18F-FDG PET/CT should be recommended for further etiological clarification.

18F-FDG PET/CT evaluation of lymphoma with renal involvement: comparison with renal carcinoma.

OBJECTIVE: Lymphoma can arise at any anatomic site, but it is rare to find kidney involvement. The aim of this study was to assess the role of F-flourodeoxyglucose (F-FDG) positron emission tomography (PET)/computed tomography (CT) in detecting lymphoma with renal involvement. Reports of such use of F-FDG PET/CT are limited. METHODS: Twelve lymphoma patients with renal involvement and 12 renal carcinoma patients were studied with F-FDG PET/CT. Intense F-FDG uptake, suggestive of positivity, was measured in mean standardized uptake values (standardized uptake values [SUV] mean). RESULTS: The results of PET/CT were validated by bone marrow, biopsy tissue and/or surgery. F-FDG PET/CT detected lymphoma with renal involvement lesions or renal carcinoma lesions in at least one site in the 24 patients. F-FDG uptake by the lymphoma lesions was much higher than the F-FDG uptake by the renal clear cell carcinomas (SUV mean 6.37 +/- 2.28 vs 2.58 +/- 0.62), and similar to that of renal cell carcinoma and renal collecting duct carcinoma (SUV mean 6.37 +/- 2.28 vs 6.27 +/- 1.15). There were dissimilar morphological changes in the homologous CT. Differing from renal cancer, lymphoma in the spleen, uterus, and bone marrow can easily be diagnosed by F-FDG PET/CT. CONCLUSION: The lesions of lymphoma with renal involvement, and especially those of primary renal lymphoma, are F-FDG avid. PET/CT appears to be useful in comparing these lesions with those of renal carcinoma, especially for primary renal lymphoma.

A Rare Case of Neutrophil-Rich, ALK-Negative Anaplastic Large Cell Lymphoma in the Lung Mimicking a Pulmonary Abscess on 18F-FDG PET/CT.

A 21-year-old man complained of cough, fever, and hemoptysis for 15 days. Peripheral neutrophil cell (33.8 × 10/L) was markedly increased, and a mass in the left lung was detected by chest radiography. F-FDG PET/CT was referred for characterizing the lesion and found a large mass with multiple cavities in the left lung, which had markedly high uptake of F-FDG, mimicking pulmonary abscess. Surprisingly, the lesion was eventually proved to be neutrophil-rich anaplastic large cell lymphoma. After 4 cycles' chemotherapy, the lesion shrank significantly.

Gummatous Syphilis Mimicking Malignant Bone Tumor on FDG PET/CT.

A 47-year-old woman suffered worsening pain in the waist and numbness in the right thigh for 1 month. MRI was performed to determine the cause, which detected an osteolytic lesion in the T12 vertebral body, suggestive of possible bone metastasis. FDG PET/CT scan was undertaken to detect the primary tumor, which only showed the same isolated lesion in the T12 without any other abnormal hypermetabolic lesion. The pathology following vertebrectomy revealed granulomatous infection. The diagnosis of osseous syphilis was eventually made following a subsequent positive Treponema pallidum serological test.

Positron-emission tomography for hepatocellular carcinoma: Current status and future prospects.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality worldwide. Various imaging modalities provide important information about HCC for its clinical management. Since positron-emission tomography (PET) or PET-computed tomography was introduced to the oncologic setting, it has played crucial roles in detecting, distinguishing, accurately staging, and evaluating local, residual, and recurrent HCC. PET imaging visualizes tissue metabolic information that is closely associated with treatment. Dynamic PET imaging and dual-tracer have emerged as complementary techniques that aid in various aspects of HCC diagnosis. The advent of new radiotracers and the development of immuno-PET and PET-magnetic resonance imaging have improved the ability to detect lesions and have made great progress in treatment surveillance. The current PET diagnostic capabilities for HCC and the supplementary techniques are reviewed herein.

Solid pseudopapillary tumor of the pancreas: clinical features and imaging findings.

This study aimed to report clinical features and CT, MRI, PET/CT findings of solid pseudopapillary tumor (SPT) of the pancreas. Thirty-four patients with pathologically proven SPT were retrospectively reviewed. Most patients were asymptomatic. SPTs in male patients mainly appeared as solid and near solid tumors. Mixed tumors and cystic tumors had larger size than solid and near solid tumors. Solid tumors and solid part of mixed tumors were T2 hyperintense and T1 hypointense and had progressive enhancement. Four tumors (80%) showed markedly even or uneven 18F-FDG uptake. These characteristic features can help differentiate SPT from other pancreatic neoplasms.

Construction and Evaluation of the Tumor-Targeting, Cell-Penetrating Multifunctional Molecular Probe iCREKA.

A novel tumor stroma targeting and membrane-penetrating cyclic peptide, named iCREKA, was designed and labeled by fluorescein isothiocyanate (FITC) and positron emitter 18F to build the tumor-targeting tracers. The FITC-iCREKA was proved to have significantly higher cellular uptake in the glioma U87 cells in the presence of activated MMP-2 than that in absence of activated MMP-2 by cells fluorescence test in vitro. The tumor tissue fluorescence microscope imaging demonstrated that FITC-iCREKA accumulated in the walls of the blood vessels and the surrounding stroma in the glioma tumor at 1 h after intravenous injection. While at 3 h after injection, FITC-iCREKA was found to be uptaken in the tumor cells. However, the control FITC-CREKA can only be found in the tumor stroma, not in the tumor cells, no matter at 1 h or 3 h after injection. The whole-animal fluorescence imaging showed that the glioma tumor could be visualized clearly with high fluorescence signal. The microPET/CT imaging further demonstrated that 18F-iCREKA could target U87MG tumor in vivo from 30 min to 2 h after injection. The present study indicated the iCREKA had the capacity of tumor stroma targeting and the membrane-penetrating. It was potential to be developed as the fluorescent and PET tracers for tumor imaging.

Low glucose metabolism in hepatocellular carcinoma with GPC3 expression.

AIM: To investigate the relationship between glucose metabolism and glypican-3 (GPC3) expression in hepatocellular carcinoma (HCC). METHODS: Immunohistochemical staining of pathological samples for GPC3 and glucose transporter 1 (GLUT1), and whole-body 18F-FDG PET/CT for measuring tumour glucose uptake were performed in 55 newly diagnosed HCC patients. The maximum standard uptake value (SUVmax) and tumour-to-non-tumourous liver uptake (T/NT) ratio were used to quantify 18F-FDG uptake. In vitro18F-FDG uptake assay of GPC3-expressing HepG2 and non-GPC3-expressing RH7777 cells was used to examine the effect of GPC3 in cellular glucose metabolism. The relationships between GPC3 expression and 18F-FDG uptake, GLUT1 expression, tumour differentiation, and other clinical indicators were analysed using Spearman rank correlation, univariate and multiple logistic regression analyses. RESULTS: Positive GPC3 expression was observed in 67.3% of HCC patients, including 75.0% of those with well or moderately differentiated HCC and 36.4% of those with poorly differentiated HCC. There was an inverse relationship between GPC3 expression and SUVmax (Spearman correlation coefficient = -0.281, P = 0.038) and a positive relationship between GLUT1 expression and SUVmax (Spearman correlation coefficient = 0.681, P < 0.001) in patients with HCC. Univariate analysis showed that two glucose metabolic parameters (SUVmax and T/NT ratio), tumour differentiation, lymph node metastasis, and TNM stage were all significantly associated with GPC3 expression (P < 0.05), whereas GLUT1 expression, sex, age, tumour size, intrahepatic lesion number, and distant metastasis showed no statistical association (P > 0.05). Further multivariate analysis revealed that only the T/N ratio was significantly correlated with GPC3 expression in patients with HCC (P < 0.05). In vitro assay revealed that the uptake of 18F-FDG in GPC3-expressing HepG2 cells was significantly lower than that of non-GPC3-expressing RH7777 cells (t = -20.352, P < 0.001). CONCLUSION: The present study demonstrated that GPC3 expression is inversely associated with glucose metabolism, suggesting that GPC3 may play a role in regulating glucose metabolism in HCC.

Human erythrocyte lifespan measured by Levitt's CO breath test with newly developed automatic instrument.

Existing standard techniques for erythrocyte (RBC) lifespan measurement, such as quantitation of labeling with isotopes or biotin, are cumbersome and time-consuming. Given that endogenous CO originates mainly from degraded RBCs, a team lead by Levitt developed a CO breath test to enable more efficient RBC lifespan estimation. The purpose of this study was to evaluate the reliability of Levitt's CO breath test method with our newly developed automatic instrument. RBC lifespan measurements conducted by Levitt's CO breath test method were conducted in 109 healthy subjects and 91 patients with chronic hemolytic anemia. In healthy subjects, the RBC lifespan was 126 ± 26 days, similar to values obtained with classical standard labeling methods. RBC lifespan did not differ significantly between males and females or between juveniles and adults, and did not correlate with age. To our knowledge, this datum represents an RBC lifespan average for the largest sample to date. In subjects with hemolytic anemia, RBC lifespan was 29 ± 14 days, which is significantly shorter than that of the healthy subjects (p = 0.001). Using 75 days as a cut-off, diagnostic accuracy for hemolytic anemia in the present study sample was 100%. In conclusion, the present results indicate that Levitt's CO breath test is an ideal method for human RBC lifespan measurement, and the newly developed automatic instrument is reliable and convenient for clinical practice.

Influence of FDG-PET on computed tomography-based radiotherapy planning for locally recurrent nasopharyngeal carcinoma.

PURPOSE: Assuming F-18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET)/computed tomography (CT) to be more accurate in representing the true disease extent than CT alone, we prospectively designed this study to evaluate how the addition of FDG-PET influences CT-based radiotherapy planning for locally recurrent nasopharyngeal carcinoma. PATIENTS AND METHODS: All patients underwent FDG-PET/CT simulation scans. For each patient, the gross tumor volume (GTV) was separately delineated with or without the addition of PET information and defined as GTV PET/CT and GTV CT, respectively. Corresponding planning target volumes (PTV) were generated for the GTV CT (PTV(CT)) and GTV PET/CT (PTV PET/CT). Three-dimensional conformal radiotherapy plans were separately created for PTV CT and PTV PET/CT. To assess the potential geographic miss of the PET/CT-based disease in CT-based treatment planning, the size and location of the GTV PET/CT, PTV(PET/CT), and PTV(CT) were analyzed, and the three-dimensional conformal radiotherapy plans created using the PTV CT were evaluated with the GTV PET/CT and PTV PET/CT information. RESULTS: A total of 43 patients were enrolled in this study. Distant metastasis was found in 4 patients with the addition of the PET information. The 39 patients without distant metastasis proceeded to three-dimensional conformal radiotherapy planning. Inadequate coverage of the GTV PET/CT and PTV PET/CT by the PTV CT occurred in 7 (18%) and 20 (51%) patients, respectively. This resulted in <95% of the GTV(PET/CT) and PTV PET/CT receiving >or=95% of the prescribed dose in 4 (10%) and 13 (33%) patients, respectively. CONCLUSIONS: The addition of FDG-PET information might influence CT-based radiotherapy planning for locally recurrent nasopharyngeal carcinoma by altering the definition of the target volume, with the potential to avoid a geographic miss of true disease.

Diagnosis and treatment of diffusible Penicillium marneffei in human immunodeficiency virus-negative patients: A challenge for the physician.

Penicillium marneffei infection in human immunodeficiency virus (HIV)-negative patients is addressed far less often. In this article, a small cohort of HIV-negative patients who disseminated P. marneffei infection was included. Sites of infection were found from blood culture, as subcutaneous nodules, or from lymph node biopsy. Fever, rash, swollen lymph nodes, anaemia and weight loss were common characteristics in most infected patients. The signs and symptoms are diverse and create challenges for accurate diagnosis. This paper will assist our understanding of this disease and contribute to an appropriate regime of therapy, thus improving the health of P. marneffei-positive patients.

PET/CT for differentiating between tuberculous peritonitis and peritoneal carcinomatosis: The parietal peritoneum.

OBJECTIVES: Tuberculous peritonitis (TBP) mimics peritoneal carcinomatosis (PC). We aimed to investigate the discriminative use of PET/CT findings in the parietal peritoneum. MATERIALS AND METHODS: Parietal peritoneal PET/CT findings from 76 patients with TBP (n = 25) and PC (n = 51) were retrospectively reviewed. The lesion locations were noted as right subdiaphragmatic, left subdiaphragmatic, right paracolic gutters, left paracolic gutters, and pelvic regions. The distribution characteristic consisted of a dominant distribution in the pelvic and/or right subdiaphragmatic region (susceptible area for peritoneal implantation, SAPI) (SAPI distribution), a dominant distribution in the remaining regions (less-susceptible area for peritoneal implantation, LSAPI) (LSAPI distribution), or a uniform distribution. PET morphological patterns were classified as F18-fluorodeoxyglucose (F-FDG) uptake in a long beaded line (string-of-beads F-FDG uptake) or in a cluster (clustered F-FDG uptake) or focal F-FDG uptake. CT patterns included smooth uniform thickening, irregular thickening, or nodules. RESULTS: More common findings in the parietal peritoneum corresponding to TBP as opposed to PC were (a) ≥4 involved regions (80.0% vs 19.6%), (b) uniform distribution (72.0% vs 5.9%), (c) string-of-beads F-FDG uptake (76.0% vs 7.8%), and (d) smooth uniform thickening (60.0% vs 7.8%) (all P < 0.001), whereas more frequent findings in PC compared with TBP were (a) SAPI distribution (78.4% vs 28.0%), (b) clustered F-FDG uptake (56.9% vs 20.0%), (c) focal F-FDG uptake (21.6% vs 4.0%), (d) irregular thickening (51.0% vs 12.0%), and (e) nodules (21.6% vs 4.0%) (P < 0.001, P < 0.05, P > 0.05, P < 0.05, P > 0.05, respectively). CONCLUSION: Our data show that PET/CT findings in the parietal peritoneum are useful for differentiating between TBP and PC.

Whole-body 18F-FDG PET/CT for M staging in the patient with newly diagnosed nasopharyngeal carcinoma: Who needs?

OBJECTIVE: Although whole-body fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) (18F-FDG PET/CT) is commonly used for M staging of newly diagnosed nasopharyngeal carcinoma (NPC), some patients may not benefit from this procedure. The present study investigated which patients require this modality for M staging. METHODS: Whole-body 18F FDG PET/CT results and clinical data were collected for 264 patients with newly diagnosed NPC. The relationships between distant metastasis and age, gender, pathological type, lesion size, SUVmax-T, T staging, N staging, SUVmax-N and Epstein-Barr virus (EBV) quantity were retrospectively analysed to identify factors associated with increased risk. RESULTS: Of the 264 patients, only 37 (14.0%) were diagnosed with distant metastasis. Using multiple logistic regression analysis, EBV-positivity (OR=13.1; 95% CI:1.61,106.80), N staging (OR=3.05; 95% CI:1.41,6.63) and T staging (OR=2.16; 95% CI:1.10, 4.24) were significantly related to distant metastasis (all P<0.05). EBV DNA levels≥9000copies/ml, N3 stage and T4 stage were identified as high risk factors. A low risk of distant metastasis was found in patients with 0-1 risk factors and in those with 2 specific risk factors, T3/T4 and N2/N3 staging. Patients with EBV DNA levels ≥9000copies/ml and N3 or T4 staging and those with 3 risk factors had a medium or high risk, with a much higher incidence of distant metastasis (χ2=29.896, P=0.000), and needed a whole-body 18F FDG PET/CT for M staging. CONCLUSIONS: Due to the low incidence of distant metastasis, only patients with medium or high risk need to undergo a whole-body scan.

[Combined use of thin-section CT and 18F-FDG PET/CT for characterization of solitary pulmonary nodules].

OBJECTIVE: To investigate whether fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) combined with thin-section CT improves the diagnostic performance for solitary pulmonary nodules (SPNs). METHODS: A total of 267 patients underwent examinations with 18F-FDG PET/CT and thin-section CT for evaluating the SPNs with undetermined nature, which was further confirmed by pathological examination or clinical follow-up. The performance of two diagnostic criteria based on findings in PET/CT alone (Criterion 1) and in PET/CT combined with thin-section CT (Criterion 2) were compared. RESULTS: Thin-section CT provided greater diagnostic information for SPNs in 84.2% of the patients. Compared with Criterion 1, the diagnosis based on Criterion 2 significantly increased the diagnostic sensitivity (80.4% vs 91%, P<0.01) and accuracy (76.4% vs 87.2%, P<0.01) for lung cancer. The lesion size and the CT features including lobulation, air bronchogram, and feeding vessel, but not SUVmax, were all helpful for characterizing non-solid SPNs. Thin-section CT rectified diagnostic errors in 50% (20/40) of the cancerous lesions, which had been diagnosed as benign by PET due to their low metabolism. For non-solid SPNs, Criterion 2 showed a significantly higher diagnostic sensitivity than Criterion 1 (90.0% vs 40.0%, P=0.000) but their diagnostic specificity were comparable (75.2% vs 58.3%, P=0.667). For solid nodules, the use of thin-section CT resulted in no significant improvement in the diagnostic performance (P<0.05). CONCLUSION: The combination of PET/CT and thin-section CT creates a synergistic effect for the characterization of SPNs, especially non-solid nodules.

Multifunctional superparamagnetic nanoparticles conjugated with fluorescein-labeled designed ankyrin repeat protein as an efficient HER2-targeted probe in breast cancer.

Based on the discordance of human epidermal growth factor receptor-2 (HER2) expression between primary and metastatic/recurrent breast cancer, HER2 molecular imaging, which had potential to systemically assess and dynamically monitor HER2 expression, might improve the selection of patients for anti-HER2 therapy. In this study, designed ankyrin repeat protein (DARPin) G3, a novel binding protein with picomolar affinity for HER2, was used and multifunctional superparamagnetic nanoparticles modified with fluorescein-5-maleimide-labeled DARPin G3 (SPIO-G3-5MF) were developed for HER2 imaging. Our results showed that SPIO-G3-5MF nanoparticles, which possessed uniform size of about 100 nm, favorable dispersity and low cytotoxicity, could selectively bind to HER2-positive breast cancer cells even in the presence of trastuzumab. Biodistribution assay demonstrated that abundant accumulation and long retention of SPIO-G3-5MF were observed in HER2-positive transplantation breast tumors although a portion of SPIO-G3-5MF nanoparticles were unavoidably captured by liver and spleen. Further MR imaging revealed that SPIO-G3-5MF could selectively image HER2-positive transplantation breast tumors, yielding remarkable T2 signal reduction (50.33 ± 2.90% at 6 h and 47.29 ± 9.36% at 24 h). Our study suggested that SPIO-G3-5MF might be a promising MR molecular probe for diagnosing and monitoring HER2 expression state of breast cancer in the future.

Influence of [18F] fluorodeoxyglucose positron emission tomography on salvage treatment decision making for locally persistent nasopharyngeal carcinoma.

PURPOSE: The purpose of this study was to evaluate the role of [18F] fluorodeoxyglucose positron emission tomography (FDG-PET) in influencing salvage treatment decision making for locally persistent nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: A total of 33 NPC patients with histologic persistence at nasopharynx 1 to 6 weeks after a full course of radiotherapy underwent both computed tomography (CT) and FDG-PET/CT simulation at the same treatment position. The salvage treatment decisions, with regard to the decision to offer salvage treatment and the definition of gross tumor volume (GTV), were made before knowledge of the FDG-PET findings. Subsequently the salvage treatment decisions were made again based on the FDG-PET findings and compared with the pre-FDG-PET decisions. RESULTS: All 33 patients were referred for salvage treatment in the pre-FDG-PET decision. After knowledge of the FDG-PET results, the decision to offer salvage treatment was withdrawn in 4 of 33 patients (12.1%), as no abnormal uptake of FDG was found at nasopharynx. Spontaneous remission was observed in repeat biopsies and no local recurrence was found in these 4 cases. For the remaining 29 patients, GTV based on FDG-PET was smaller than GTV based on CT in 24 (82.8%) cases and was greater in 5 (17.2%) cases, respectively. The target volume had to be significantly modified in 9 of 29 patients (31%), as GTV based on FDG-PET images failed to be enclosed by the treated volume in the salvage treatment plan performed based on GTV based on CT simulation images. CONCLUSION: Use of FDG-PET was found to influence the salvage treatment decision making for locally persistent NPC by identifying patients who were not likely to benefit from additional treatment and by improving accuracy of GTV definition in salvage treatment planning.