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One important aim of precision oncology is a personalized treatment of patients. This can be achieved by various biomarkers, especially imaging parameters and gene expression signatures are commonly used. So far, combination approaches are sparse. The aim of the study was to independently validate the prognostic value of the novel positron emission tomography (PET) parameter tumor asphericity (ASP) in non small cell lung cancer (NSCLC) patients and to investigate associations between published gene expression profiles and ASP. This was a retrospective evaluation of PET imaging and gene expression data from three public databases and two institutional datasets. The whole cohort comprised 253 NSCLC patients, all treated with curative intent surgery. Clinical parameters, standard PET parameters and ASP were evaluated in all patients. Additional gene expression data were available for 120 patients. Univariate Cox regression and Kaplan-Meier analysis was performed for the primary endpoint progression-free survival (PFS) and additional endpoints. Furthermore, multivariate cox regression testing was performed including clinically significant parameters, ASP, and the extracellular matrix-related prognostic gene signature (EPPI). In the whole cohort, a significant association with PFS was observed for ASP (p < 0.001) and EPPI (p = 0.012). Upon multivariate testing, EPPI remained significantly associated with PFS (p = 0.018) in the subgroup of patients with additional gene expression data, while ASP was significantly associated with PFS in the whole cohort (p = 0.012). In stage II patients, ASP was significantly associated with PFS (p = 0.009), and a previously published cutoff value for ASP (19.5%) was successfully validated (p = 0.008). In patients with additional gene expression data, EPPI showed a significant association with PFS, too (p = 0.033). The exploratory combination of ASP and EPPI showed that the combinatory approach has potential to further improve patient stratification compared to the use of only one parameter. We report the first successful validation of EPPI and ASP in stage II NSCLC patients. The combination of both parameters seems to be a very promising approach for improvement of risk stratification in a group of patients with urgent need for a more personalized treatment approach.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Prognóstico , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Fluordesoxiglucose F18/metabolismo , Tomografia Computadorizada por Raios X , Medicina de Precisão , Tomografia por Emissão de Pósitrons combinada à Tomografia ComputadorizadaRESUMO
The objective of this study was to assess the prognostic value of asphericity (ASP) and standardized uptake ratio (SUR) in cervical cancer patients. Retrospective analysis was performed on a group of 508 (aged 55 ± 12 years) previously untreated cervical cancer patients. All patients underwent a pretreatment [18F]FDG PET/CT study to assess the severity of the disease. The metabolic tumor volume (MTV) of the cervical cancer was delineated with an adaptive threshold method. For the resulting ROIs the maximum standardized uptake value (SUVmax) was measured. In addition, ASP and SUR were determined as previously described. Univariate Cox regression and Kaplan-Meier analysis with respect to event free survival (EFS), overall survival (OS), freedom from distant metastasis (FFDM) and locoregional control (LRC) was performed. Additionally, a multivariate Cox regression including clinically relevant parameters was performed. In the survival analysis, MTV and ASP were shown to be prognostic factors for all investigated endpoints. Tumor metabolism quantified with the SUVmax was not prognostic for any of the endpoints (p > 0.2). The SUR did not reach statistical significance either (p = 0.1, 0.25, 0.066, 0.053, respectively). In the multivariate analysis, the ASP remained a significant factor for EFS and LRC, while MTV was a significant factor for FFDM, indicating their independent prognostic value for the respective endpoints. The alternative parameter ASP has the potential to improve the prognostic value of [18F]FDG PET/CT for event-free survival and locoregional control in radically treated cervical cancer patients.
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Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Transporte BiológicoRESUMO
PURPOSE: PET-derived metabolic tumor volume (MTV) and total lesion glycolysis of the primary tumor are known to be prognostic of clinical outcome in head and neck cancer (HNC). Including evaluation of lymph node metastases can further increase the prognostic value of PET but accurate manual delineation and classification of all lesions is time-consuming and prone to interobserver variability. Our goal, therefore, was development and evaluation of an automated tool for MTV delineation/classification of primary tumor and lymph node metastases in PET/CT investigations of HNC patients. METHODS: Automated lesion delineation was performed with a residual 3D U-Net convolutional neural network (CNN) incorporating a multi-head self-attention block. 698 [Formula: see text]F]FDG PET/CT scans from 3 different sites and 5 public databases were used for network training and testing. An external dataset of 181 [Formula: see text]F]FDG PET/CT scans from 2 additional sites was employed to assess the generalizability of the network. In these data, primary tumor and lymph node (LN) metastases were interactively delineated and labeled by two experienced physicians. Performance of the trained network models was assessed by 5-fold cross-validation in the main dataset and by pooling results from the 5 developed models in the external dataset. The Dice similarity coefficient (DSC) for individual delineation tasks and the primary tumor/metastasis classification accuracy were used as evaluation metrics. Additionally, a survival analysis using univariate Cox regression was performed comparing achieved group separation for manual and automated delineation, respectively. RESULTS: In the cross-validation experiment, delineation of all malignant lesions with the trained U-Net models achieves DSC of 0.885, 0.805, and 0.870 for primary tumor, LN metastases, and the union of both, respectively. In external testing, the DSC reaches 0.850, 0.724, and 0.823 for primary tumor, LN metastases, and the union of both, respectively. The voxel classification accuracy was 98.0% and 97.9% in cross-validation and external data, respectively. Univariate Cox analysis in the cross-validation and the external testing reveals that manually and automatically derived total MTVs are both highly prognostic with respect to overall survival, yielding essentially identical hazard ratios (HR) ([Formula: see text]; [Formula: see text] vs. [Formula: see text]; [Formula: see text] in cross-validation and [Formula: see text]; [Formula: see text] vs. [Formula: see text]; [Formula: see text] in external testing). CONCLUSION: To the best of our knowledge, this work presents the first CNN model for successful MTV delineation and lesion classification in HNC. In the vast majority of patients, the network performs satisfactory delineation and classification of primary tumor and lymph node metastases and only rarely requires more than minimal manual correction. It is thus able to massively facilitate study data evaluation in large patient groups and also does have clear potential for supervised clinical application.
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Neoplasias de Cabeça e Pescoço , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18/metabolismo , Metástase Linfática/diagnóstico por imagem , Carga Tumoral , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Redes Neurais de ComputaçãoRESUMO
Lung cancer is the leading cause of cancer-related death worldwide. Planar radiography and computed tomography are the most common imaging modalities used in diagnosis, staging, and therapy response assessment. However, the role of nuclear methods in assessing the severity of the disease and the effectiveness of treatment has increased in recent years. Introducing these diagnostic modalities into standard practice in lung cancer may contribute to the personalization of treatment. In this review, we summarize the current knowledge of nuclear medicine techniques in the diagnosis and treatment of lung cancer.
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Background: The purpose of the study was to discuss whether 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) study protocol should include brain imaging. Materials and methods: Analysis of international societies recommendations compared with the original data obtained in over 1000 consecutive torso and brain 18F-FDG PET/CT studies collected in 2010. Results: According to the international societies recommendations, the 18F-FDG should not be the radiotracer of choice considering the brain region PET/CT study. However, it can be performed as an additional brain imaging tool. Based on at least a 3-year follow-up, we detected 8 cases of suspicious brain findings and no primary lesion among over 1000 consecutive torso and brain 18F-FDG PET/CT scans performed in 2010. However, in 5 out of 8 patients, the brain lesion was the only metastasis detected, affecting further therapy. Conclusions: The 18F-FDG PET/CT study may help detect malignant brain lesions and, therefore, including brain region imaging into the study protocol should be considered.
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The oncological treatment can significantly affect patients' health-related quality of life (HRQoL), which should be monitored to ensure our patients' well-being. The often-used HRQoL measurer is the quality-adjusted life-year (QALY) indicator of the disease burden, describing both quality and quantity of life lived. The main aim of the study was to discuss the methodology and usefulness of evaluating QALYs using the HRQoL questionnaires: EuroQoL (EQ)-5 dimensions-3 levels (EQ-5D-3L) and EQ visual analogue scale (EQ-VAS) in 32 cervical cancer patients. We obtained the questionnaire and calculated QALYs based on the Gross Domestic Product (GDP) method. In our study, the total scoring of the EQ-Index, EQ-VAS evaluation was 2620 and 2409 points, respectively, which corresponds with the QALYs value of 26.2 and 24.9, respectively. We expressed the QALYs outcome into the economic equivalent of nearly 900,000 US dollars (USD) as the total health profit for both the patients and the healthcare system. Obtaining the QALY factor can help establish the medical management's influence on the patients' HRQoL and improve the healthcare services to ensure the best health outcomes.
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Qualidade de Vida , Humanos , Medição da Dor , Anos de Vida Ajustados por Qualidade de Vida , Inquéritos e Questionários , Escala Visual AnalógicaRESUMO
Purpose: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is utilized for staging and treatment planning of head and neck squamous cell carcinomas (HNSCC). Some older publications on the prognostic relevance showed inconclusive results, most probably due to small study sizes. This study evaluates the prognostic and potentially predictive value of FDG-PET in a large multi-center analysis. Methods: Original analysis of individual FDG-PET and patient data from 16 international centers (8 institutional datasets, 8 public repositories) with 1104 patients. All patients received curative intent radiotherapy/chemoradiation (CRT) and pre-treatment FDG-PET imaging. Primary tumors were semi-automatically delineated for calculation of SUVmax, SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Cox regression analyses were performed for event-free survival (EFS), overall survival (OS), loco-regional control (LRC) and freedom from distant metastases (FFDM). Results: FDG-PET parameters were associated with patient outcome in the whole cohort regarding clinical endpoints (EFS, OS, LRC, FFDM), in uni- and multivariate Cox regression analyses. Several previously published cut-off values were successfully validated. Subgroup analyses identified tumor- and human papillomavirus (HPV) specific parameters. In HPV positive oropharynx cancer (OPC) SUVmax was well suited to identify patients with excellent LRC for organ preservation. Patients with SUVmax of 14 or less were unlikely to develop loco-regional recurrence after definitive CRT. In contrast FDG PET parameters deliver only limited prognostic information in laryngeal cancer. Conclusion: FDG-PET parameters bear considerable prognostic value in HNSCC and potential predictive value in subgroups of patients, especially regarding treatment de-intensification and organ-preservation. The potential predictive value needs further validation in appropriate control groups. Further research on advanced imaging approaches including radiomics or artificial intelligence methods should implement the identified cut-off values as benchmark routine imaging parameters.
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The aim of this study is to assess the influence of semiquantitative PET-derived parameters as well as hematological parameters in overall survival in HNSCC patients using neural network analysis. Retrospective analysis was performed on 106 previously untreated HNSCC patients. Several PET-derived parameters (SUVmax, SUVmean, TotalSUV, MTV, TLG, TLRmax, TLRmean, TLRTLG, and HI) for primary tumor and lymph node with highest activity were assessed. Additionally, hematological parameters (LEU, LEU%, NEU, NEU%, MON, MON%, PLT, PLT%, NRL, and LMR) were also assessed. Patients were divided according to the diagnosis into the good and bad group. The data were evaluated using an artificial neural network (Neural Analyzer version 2.9.5) and conventional statistic. Statistically significant differences in PET-derived parameters in 5-year survival rate between group of patients with worse prognosis and good prognosis were shown in primary tumor SUVmax (10.0 vs. 7.7; p = 0.040), SUVmean (5.4 vs. 4.4; p = 0.047), MTV (23.2 vs. 14.5; p = 0.010), and TLG (155.0 vs. 87.5; p = 0.05), and mean liver TLG (27.8 vs. 30.4; p = 0.031), TLRmax (3.8 vs. 2.6; p = 0.019), TLRmean (2.8 vs. 1.9; p = 0.018), and in TLRTLG (5.6 vs. 2.3; p = 0.042). From hematological parameters, only LMR showed significant differences (2.5 vs. 3.2; p = 0.009). Final neural network showed that for ages above 60, primary tumors SUVmax, TotalSUV, MTV, TLG, TLRmax, and TLRmean over (9.7, 2255, 20.6, 145, 3.6, 2.6, respectively) are associated with worse survival. Our study shows that the neural network could serve as a supplement to PET-derived parameters and is helpful in finding prognostic parameters for overall survival in HNSCC.
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The aim of this study was to assess the usefulness of pretherapeutic primary tumor metabolic tumor volume (MTV) in the prognosis of radically treated cervical cancer patients. Retrospective, single-centre analysis was performed on a group of 508 cervical cancer patients. All patients underwent a pretreatment [18F]FDG PET/CT study for the assessment of the disease stage. Several PET-derived parameters-namely, maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), total lesion glycolysis (TLG) and MTV, as well as the clinical parameters, were analysed in terms of the overall survival (OS), event-free survival (EFS), locoregional control (LRC) and freedom from distant metastases (FFDM). Hyperthermia and brachytherapy were prognostic for EFS, OS, and LRC.FIGO stage > II showed a significant effect on EFS, OS, and FFDM. Moreover, hysterectomy was prognostic for OS and histology was prognostic for FFDM. From the PET-derived parameters only MTV of the primary tumor had a significant influence on OS (cutoff point: >12.7 mL, HR: 2.8, 1.75-4.48 95% CI, p < 0.001), LRC (cutoff point: >13.7 mL, HR 2.82, 1.42-5.61 95% CI, p = 0.003), EFS (cutoff point: >10.4 mL, HR: 2.57, 1.67-3.97 95% CI, p < 0.001) and FFDM (cutoff point: >10.4 mL, HR: 5.04, 1.82-13.99 95% CI, p = 0.002). Pretreatment MTV from the primary tumor is the only independent prognostic parameter in OS, LRC, EFS, and FFDM in radically treated cervical cancer patients and should be used in clinical practice in assessing prognosis in these patients.
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INTRODUCTION: According to the literature, fluor-18-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG-PET-CT) is the most effective technique for the examination and detection of metastases in the lymph nodes in patients with cervical cancer. This study aimed to compare the diagnostic value of the preoperative evaluation using 18F-FDG-PET-CT with a histopathological examination of the lymph nodes removed during radical hysterectomy and pelvic lymph node dissection in patients with cervical cancer. MATERIAL AND METHODS: Retrospective analysis covered the medical records of 42 patients with cervical cancer (stage IA-IB according to International Federation of Gynaecology and Obstetrics 2009) treated with radical Piver type III hysterectomy and pelvic lymph node dissection. The preoperative diagnosis was made using a PET/CT examination. Results: The result of the 18F-FDG-PET-CT examination highlighted a suspicion of lymph node metastases in 13 patients (31%). The histopathological examination confirmed this in 12 patients (29%). Metastatic lymph nodes were correctly diagnosed using 18F-FDG-PET-CT in 8 out of the 12 cases confirmed by the histopathological examination. In the patient-based study, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 66.8%, 83.3%, 61.5%, 86.2 % and 78.6%, respectively. CONCLUSIONS: We confirmed the usefulness of PET in the preoperative assessment of cervical cancer advancement, especially in correlation with the new 2018 International Federation of Gynaecology and Obstetrics staging system.
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The study aimed to show that including the brain region into the standard 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) study protocol may result in detecting clinically silent brain tumours. We retrospectively analyzed the group of 10,378 from the total of 12,011 consecutive patients who underwent the torso and brain [18F]FDG PET/CT scanning, considering an ability of the method to evaluate undetected before brain tumours in patients diagnosed and treated in our institution. While collecting the database, we followed the inclusion criteria: at least 1-year of follow-up, a full medical history collected in our institution, histopathologic examination or other studies available to confirm the type of observed lesion, and the most importantly-no brain lesions reported in the patients' medical data. In this study, performing the torso and brain [18F]FDG PET/CT imaging helped to detect clinically silent primary and metastatic brain tumours in 129 patients, and the benign lesions in 24 studied cases, in whom no suspicious brain findings were reported prior to the examination. In conclusion, including the brain region into the standard [18F]FDG PET/CT protocol can be considered helpful in detecting clinically silent malignant and benign brain tumours.
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Neoplasias Encefálicas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neuroimagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos RetrospectivosRESUMO
According to the international societies' recommendations, the 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) technique should not be used as the method of choice in brain tumour diagnosis. Therefore, the brain region can be omitted during standard [18F]FDG PET/CT scanning. We performed comprehensive literature research and analysed results from 14,222 brain and torso [18F]FDG PET/CT studies collected in 2010-2020. We found 131 clinically silent primary and metastatic brain tumours and 24 benign lesions. We concluded that the brain and torso [18F]FDG PET/CT study provides valuable data that may support therapeutic management by detecting clinically silent primary and metastatic brain tumours.
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PURPOSE: This study aims to determine whether semiquantitative parameters obtained from both the primary tumor and metastatic pelvic lymph nodes (PLN) diagnosed in fluoro-18-deoxy-glucose positron emission tomography (FDG-PET-CT) are associated with disease-free survival (DFS), local control (LC), distant metastasis-free survival (DMFS) and overall survival (OS) in patients with locally advanced squamous cervical cancer (LACC) and metastatic pelvic lymph nodes. MATERIALS: Retrospective analysis was performed on 93 female patients with FIGO IIIC1. The median age was 53 years (27-75). The PET parameters both in the primary tumor and metastatic pelvic lymph nodes, including SUVmax, SUVmean, TLG, MTV, heterogeneity, along with clinical variables, before radical cisplatin-based radiochemotherapy (RCT) were analyzed. The p-values < 0.05 were considered statistically significant. RESULTS: Median follow-up was 38 months (4.5-92.6). Three years and five years OS were 75% and 70% respectively. Patients with SUVmax above 12.6, SUVmean above 7.6 and with TLG in tumors >245.7 lived longer (p < 0.05). The higher SUVmax or SUVmean reduced increased DMFS (HR 0.3 95%CI 0.56-0.96 and 0.59 95%CI 0.37-0.93). The clinical factors and other FDG PET CT parameters were not found to be statistically relevant in terms of OS, DFS, DM and LC. CONCLUSIONS: This study is the first report showing that in LACC patient population with PLN involvement treated with definitive RCT, high SUVmean, SUVmax and TLG of the primary tumor in FDG-PET-CT were linked with longer OS. Lower SUVmean and SUVmax were linked with shorter DMFS. None of the clinical factors and the nodal FDG-PET-CT parameters influenced the outcome.
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An ectopic pregnancy occurs in approximately 0.5-2% of all pregnancies. The number of cases of cervical cancer in women under 30 years of age in Poland is less than 100 cases per year. The case presented herein concerns a rare clinical situation of a 29-year-old woman admitted to the Gynaecological Oncology Department with a diagnosis of cervical cancer. The main symptom resulting in the patient's referral was ascites. The presence of free fluid in the peritoneal cavity in patients diagnosed with a malignant tumour suggests a high degree of progression of the underlying disease, though this could not be confirmed in a clinical study in this case. An interview, examination, and laboratory tests confirmed a coexisting life-threatening ruptured tubal pregnancy. The consequences of not recognising both an ectopic pregnancy and cervical cancer in a patient presenting with nonspecific clinical symptoms could pose a serious threat to health and life.
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This study aims to investigate if vaginal bacteriology obtained prior to treatment influences the 3'-deoxy-3 18F-fluorothymidine (FLT) [18F]FLT and 2-deoxy-2-[18F]fluoro-d-glucose (2-[18F]FDG) [18F]FDG parameters in positron emission tomography (PET/CT) in cervical cancer (CC) patients. METHODS: Retrospective analysis was performed on 39 women with locally advanced histologically confirmed cervical cancer who underwent dual tracer PET/CT examinations. The [18F]FLT and [18F]FDG PET parameters in the primary tumor, including SUVmax, SUVmean, MTV, heterogeneity, before radiotherapy (RT) were analyzed, depending on the bacteriology. The p-values < 0.05 were considered statistically significant. RESULTS: In the vaginal and/or cervical smears, there were 27 (79.4%) positive results. In seven (20.6%) cases, no opportunistic pathogen growth was observed (No Bacteria Group). In positive bacteriology, eleven (32%) Gram-negative bacilli (Bacteria group 2) and fifteen (44%) Gram-positive bacteria (Bacteria group 1) were detected. Five patients with unknown results were excluded from the analysis. Data analysis shows a statistically significant difference between the SUVmax, and SUVmin values for three independent groups for the [18F]FLT. CONCLUSIONS: The lowest values of SUVmax and SUVmin for [18F]FLT are registered in Gram-negative bacteria, higher are in Gram-positive, and the absence of bacteria causes the highest [18F]FLT values.
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One of the most critical elements in the palatine tonsils (PT) patients' management is to distinguish chronic tonsillitis and malignant tumor. The single-time-point (STP) 2-deoxy-2-[18 F]fluoro-D-glucose positron emission tomography/computed tomography (18 F-FDG PET/CT) examination offers the most significant sensitivity and specificity in the head and neck (H&N) region evaluation among commonly used methods of imaging. However, introducing dual-time-point (DTP) scanning might improve the specificity and sensitivity of the technique, limited by the 18 F-FDG non-tumor-specific patterns, especially when comparing different metabolic parameters. The study aims to compare several surrogates of the maximal standardized uptake value (SUVmax), obtained in 36 subjects, divided into confirmed by pathologic study PT cancer and tonsillitis in patients who underwent DTP 18 F-FDG PET/CT scanning. In this study, we observed the increased sensitivity and the specificity of the DTP 18 F-FDG PET/CT when compared with the standard PET/CT protocol. It could be concluded that DTP 18 F-FDG PET/CT improves the PT cancer and chronic tonsillitis differential diagnosis.
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AIM: To evaluate whether the sequential dual-time-point fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (DTP 18F-FDG PET/CT) study improves the differential diagnosis in the larynx. BACKGROUND: In some cases, the clinical and metabolic similarity of laryngitis and larynx cancer make differential diagnostics difficult when performing standard 18F-FDG PET/CT examinations; therefore, an additional study protocol performance seems to be of reasonable value. MATERIALS AND METHODS: 90 patients (mean age: 61 ± 11 years, range: 41-84 years): 23 women (mean age: 63 ± 10 years, range: 51-84 years) and 67 men (mean age: 61 ± 11 years, range: 41-80 years) underwent delayed 18F-FDG PET/CT examinations at 60 and 90 min post intravenous injection (p.i.) of the radiopharmaceutical 18F-FDG. We compared the metabolic activity of 90 structures divided into following groups: normal larynx (30 patients), laryngitis (30 lesions) and larynx cancer (30 tumors) with maximal and mean standardized uptake value (SUVmax, SUVmean) and the retention index (RI-SUVmax). We used the receiver operating characteristics (ROC) curve to evaluate the SUVmax cut-off values. RESULTS: The SUVmax cut-off value at 60 and 90 min p.i. of 2.3 (sensitivity/specificity: 96.4%/100%) and 2.4 (94.2%/100%), respectively, distinguished normal and abnormal metabolic activity in the larynx. When laryngitis and tumors were compared, the SUVmax cut-off values obtained after initial and delayed imaging were 3.6 (87.5%/52.0%) and 6.1 (58.3%/84%), respectively. The RI-SUVmax of 1.3% (71.4%/88.1%) suggested abnormality, while RI-SUVmax of 6.6%, malignant etiology (75.0%/80.0%). CONCLUSIONS: In this study, the sequential DTP scanning protocol improved the sensitivity and specificity of the PET/CT method in terms of differential diagnosis within the larynx.
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AIM: The aim of the study was to compare semiquantitative metabolic parameters of primary tumor assessed in vivo in 18F-FDG- and 18F-FLT in cervical cancer patients. MATERIAL & METHODS: 39 patients with histologically confirmed cervical cancer underwent PET/CT scans acquired on separate days 60âmin after i.âv. injection of 364â±â75âMBq of 18F-FDG and 259â±â40âMBq of 18F-FLT. The reconstructed PET images were evaluated using a dedicated workstation for primary tumor semiquantitative parameters: SUVmax, MTV, TLG (for 18F-FLT-TLP) and heterogeneity (AUC-CSH). Wilcoxon-Mann-Whitney test and ROC curves were used for statistical analysis. Based on data from the local cancer registry and 3y- to -5y follow up patients were divided into 2 groups with regard to prognosis. Also differences between histopathological type and FIGO classification in two tracers were assessed. RESULTS: Depending on PET/CT results, patients were divided into 3 groups: group 1 with disease limited only to the cervix, group 2 with disease limited to the cervix and iliac lymph nodes, and group 3 with disseminated disease. Statistically significant differences were found between keratinizing and non-keratinizing SCC in SUVmax (pâ=â0.03) and AUC-CSH (pâ=â0.04) only in 18F-FLT-PET/CT. Following cut-off values for nodal involvement in SUVmax, MTV, TLG/TLP and AUC-CSH were calculated using ROC curves: 13.5, 39.22, 255.94, 0.59 respectively for 18F-FDG and 12.1, 37.59, 140.01, 0.46 respectively for 18F-FLT. Higher values in both tracers in MTV and TLG/TLP were found in a group with worse prognosis. CONCLUSION: This preliminary study suggests that higher values in MTV and TLG/TLP in both tracers might be associated with worse outcome in cervical cancer patients.