Significance Of Positron Emission Tomography Research Articles

ПОЗИТРОННО-ЭМИССИОННОЙ ТОМОГРАФИЯ С 18F-ФДГ В ДИАГНОСТИКЕ ЭНДОКАРДИТА ПРОТЕЗИРОВАННОГО КЛАПАНА СЕРДЦА

Purpose. The purpose of the article is to evaluate the diagnostic significance of positron emission tomography / computed tomography with 18F -fluorodeoxyglucose (18F -FDG PET/CT) for the diagnosis of prosthetic endocarditis. Methods of research. The study included 82 patients with suspected prosthetic endocarditis in accordance with the criteria proposed by Duke University [1-5]. The patients received hospital treatment at the State Institution RSPC "Cardiology" from January 2016 to March 2021. The study was of a prospective, non-randomized, single-center cohort design. The duration of the monitor period was 12 months from the moment of patients’ inclusion in the study. Whole-body positron emission tomography / computed tomography (PET/CT) examinations were performed in 82 patients. 27 patients were selected for surgical treatment. Conservative treatment group included 16 patients. 27 patients were selected into the observation group, they were suspected to have prosthetic heart valve infection in the primary referral and underwent PET/CT scanning, according to which the diagnosis of prosthetic endocarditis was excluded. The event under the study did not develop in this group during the year of observation. Results and conclusion. The history of infective endocarditis was not statistically significant and did not increase the risk of developing prosthetic endocarditis in the sample presented. The Duke criteria are less reliable in establishing the diagnosis of prosthetic endocarditis. The median number of days from the date of the first prosthesis implantation to the onset of prosthetic endocarditis was about 4 years. This study revealed that the development of the infectious process in the area of the prosthesis was noted in a more distant postoperative period compared to literature data. Histological confirmation of infection was noted in 100% (27 patients) of cases in reoperated patients. The presence of a more formidable complication such as valve ring abscess located mainly in the projection of the aortic valve ring was quite common in both groups. Presepsin and Interleukin-6 have a statistically significant (U = 394,50 p = 0,01 and U = 94,50 p = 0.004) value in the prognosis of prosthetic endocarditis. Considering the data obtained from ROC analysis, it can be said that the cut-off point at which it is possible to diagnose prosthetic endocarditis based on PETCT is 2.85. The presented methods for the interpretation of whole-body FDG-PET/CT images of patients with suspected infectious complications after cardiac surgery, as well as with the presence of prosthetic endocarditis, show high sensitivity and specificity.

FDG-PET parameters predict for recurrence in anal cancer \u2013 results from a prospective, multicentre clinical trial

BackgroundTo investigate the prognostic significance of positron emission tomography (PET) parameters from F-18 fluorodeoxyglucose (FDG) PET scans performed pre- and post- chemo-radiotherapy (CRT) for squamous cell carcinoma of the anal canal (AC).MethodsFrom January 2013 to January 2017, 19 patients with non-metastatic AC enrolled on a prospective trial underwent FDG-PET/CT imaging before and 12 weeks following CRT. A computer-generated volume of interest (VOI) was snapped around the primary tumour using six different standard uptake value (SUV) thresholds and the following parameters were extracted: SUV max, mean, median, standard deviation and peak as well as metabolic tumour volume (MTV) and total lesion glycolysis. Exact logistic regression and ROC AUC analyses were performed for each metric at each timepoint.ResultsWith a median follow up of 15.8 months, 3/19 patients had a local recurrence and 5/19 had any recurrence. On post-CRT PET, the median SUV within a VOI bounded by an SUV of 3 correlated with local recurrence (p < 0.01) and demonstrated excellent discrimination (ROC AUC 1.00, perfect separation was achieved at a median SUV of 3.38). The mean SUV at this threshold did not quite reach significance for prediction of local recurrence (p = 0.06) but demonstrated excellent discrimination (ROC AUC 0.91). The MTV bounded by a threshold of 41% SUVmax on the pre-CRT PET predicted for any recurrence (p = 0.03) and showed excellent discrimination (ROC AUC 0.89).ConclusionsFDG-PET parameters are predictive of recurrence in AC. FDG-PET may represent a valuable tool for prognostication and response assessment in AC.Trial registrationANZCTR, ACTRN12614001219673. Registered 19 November 2014 - Retrospectively registered.

Clinical Significance of Positron Emission Tomography in Subcentimeter Non-Small Cell Lung Cancer

This study evaluated the clinical significance of maximum standardized uptake value (SUVmax) on positron emission tomography (PET) in patients with subcentimeter non-small cell lung cancer (NSCLC). Between 2008 and 2014, 189 patients were investigated preoperatively by PET for c-N0 subcentimeter NSCLC, and SUVmax was reviewed. Pathologic invasiveness (PI) was defined as having at least one of the following factors: lymphatic invasion, vascular invasion, pleural invasion, or nodal metastasis. Survival rates were calculated by Kaplan-Meier estimation methods using the log-rank test. Mean SUVmax was 1.7 ± 1.8 (range, 0.6 to 13.0), and the median was 1.0. PI was found in 28 (15%) patients with subcentimeter NSCLC. Multivariate analysis revealed that SUVmax was an independent significant clinical predictor of PI (p= 0.0251) and a prognostic factor of overall survival (OS) (p= 0.0485). A receiver operating characteristics curve elucidated the predictive cutoff value of PI as SUVmax= 2.0. The high-SUVmax group (SUVmax >2.0; n= 42) had significantly more radiologically pure-solid lesions (91% vs 14%; p < 0.0001) and postoperative nodal involvement (12% vs 0%; p<0.0001) than the low-SUVmax group (SUVmax ≤2.0; n= 147). The 5-year lung cancer-specific OS (LCS-OS) elucidated significant difference between the high-SUVmax and low-SUVmax arms of the study (LCS-OS: 92.3% vs 96.9%, respectively; p= 0.0054), and cancer recurrence was found exclusively in pure-solid subcentimeter NSCLC on thin-section computed tomography. In the high-SUVmax arm of the study, lobectomy was associated with better 3-year recurrence-free survival compared with sublobar resection despite the subcentimeter disease (88.3% vs 50.0%; p= 0.0453). SUVmax on PET reflected tumor invasiveness and had a great impact on the prognosis of subcentimeter NSCLC, especially when a tumor showed a pure-solid appearance on a thin-section computed tomography scan.

Outcomes of patients with solitary plasmacytomas (SP) in the era of PET imaging and serum-free light chain (sFLC) testing: A single institution experience.

8608 Background: SP can occur in bone (SPB) or in extramedullary sites (EMP) and generally accounts for ~ 3-5% of plasma cell dyscrasias. Up to 50% of SPB and 15% of EMP will progress to multiple myeloma (MM). We evaluated the utility and prognostic significance of positron emission tomography (PET) imaging and SFLC ratio (sFLCr). Methods: We retrospectively reviewed electronic medical records of patients with SP evaluated at Moffitt Cancer Center between 1990-2012. The diagnosis of SP was per IMWG criteria (BJH 2003, 121:749) (biopsy proven single site, negative skeletal survey, bone marrow biopsy with no more than 10% plasma cells). Initial and post therapy sFLCr as well as PET findings were correlated with progression to symptomatic MM (PFS). Radiation therapy (XRT) was at the discretion of the treating physician. Results: 135 patients were identified and 91 (67%) were males. The median age was 58 years (range 20-82). Consistent with prior reports, the PFS of the entire cohort was 43 months (95% CI 17.8-70). 23 patients had PET prior to progression. All patients had uptake in the primary lesion (except 4 who had resection of the primary). 8 patients had additional PET findings in other bony structure (PET+), and 15 did not (PET-). 2 and 6 of the PET- and PET+ patients progressed (median PFS Not reached (NR) vs. 8.1 months, p=0.021) respectively. Of the 49 patients with available sFLC data, 32 had an abnormal ratio (17 progressed) and 17 patients had a normal ratio (2 progressed). Abnormal baseline sFLCr was associated with progression (median PFS 19 months vs NR, p=0.012). Post XRT, 44 patients had an available sFLCr, of which 23 had an abnormal ratio and 21 a normal ratio. A persistent serum/urine m spike after XRT was associated with progression to MM (median PFS 20.8 months vs NR, p&lt;0.0001). However, the association between Post XRT sFLCr and progression to MM was not statistically significant (median PFS 19 vs 43 months (abnormal vs normal ratio) p=0.2). Conclusions: PET imaging and sFLC are predictors of outcomes in SP and their routine inclusion in the diagnostic work up of patients with SP will result in a stage migration where patients outcomes are improved compared to historical controls.

18F]FET-PET Imaging for Treatment and Response Monitoring of Radiation Therapy in Malignant Glioma Patients – A Review

In the treatment of patients suffering from malignant glioma, it is a paramount importance to deliver a high radiation dose to the tumor on the one hand and to spare organs at risk at one the other in order to achieve a sufficient tumor control and to avoid severe side effects. New radiation therapy techniques have emerged like intensity modulated radiotherapy and image guided radiotherapy that help facilitate this aim. In addition, there are advanced imaging techniques like Positron emission tomography (PET) and PET/CT which can help localize the tumor with higher sensitivity, and thus contribute to therapy planning, tumor control, and follow-up. During follow-up care, it is crucial to differentiate between recurrence and treatment-associated, unspecific lesions, like radiation necrosis. Here, too, PET/CT can facilitate in differentiating tumor relapse from unspecific changes. This review article will discuss therapy response criteria according to the current imaging methods like Magnet resonance imaging, CT, and PET/CT. It will focus on the significance of PET in the clinical management for treatment and follow-up.

Evaluation of sequential FDG-PET/CT for monitoring bone metastasis of breast cancer during therapy: correlation between morphological and metabolic changes with tumor markers

The purpose of this study was to clarify the significance of positron emission tomography (PET) and computed tomography (CT) findings for evaluating the bone metastasis of breast cancer during therapy. Forty-seven patients with bone metastases from breast cancer who underwent sequential FDG-PET/CT studies during therapy were enrolled. A total of 771 lesions were identified. The changes in the PET and CT findings were compared with the tumor marker levels in each patient by calculating the weighted kappa value. The correlation between the PET and CT findings was examined for each lesion by an adjusted Chi-square test. The change in the tumor marker levels was substantially correlated with the PET findings and moderately correlated with the CT findings (weighted kappa=0.780 and 0.585 for quadratic weighting, respectively). An increase in FDG uptake was correlated with lytic changes on the CT images (62/65, 95.4%, p<0.05). Sclerotic changes suggested improvement, but sclerosis and progression occurred at the same time in some lesions. Changes of FDG uptake are useful for evaluating individual bone metastases in cases of breast cancer during therapy. Lytic change on CT images suggests progression of bone metastasis. The lysis-progression/sclerosis-improvement pattern was observed in the majority of subjects, but a sclerosis-progression pattern was also observed. The hybrid pattern of increase of FDG uptake on PET/lytic change on CT is most accurate to show progression of bone metastases. Assessments of these processes during therapy are necessary for the precise evaluation of bone metastases.

Positron Emission Tomography/Computed Tomography and Lymphovascular Invasion Predict Recurrence in Stage I Lung Cancers

Although pathologic stage I lung cancers generally have a favorable prognosis, approximately 20% of patients experience recurrence after surgery. Therefore, a method of selecting patients who need adjuvant therapy is necessary. The goal of this study was to evaluate the significance of positron emission tomography (PET)/computed tomography (CT) results after lung cancer surgery and to identify the predictive factors for recurrence in cases of pathologic stage I lung cancer. From January 2004 to December 2008, 356 patients with lung cancer underwent surgery at our institution. Of these, 282 patients received F-18 fluorodeoxyglucose PET/CT, and the maximum standardized uptake value (max SUV) was measured. There were 201 patients with pathologic stages IA and IB evaluated. The associations between disease-free survival (DFS) and the following clinicopathological factors were analyzed: age, gender, smoking history, carcinoembryonic antigen level, tumor size, max SUV values, histology, and lymphovascular and pleural invasion. The 4-year DFS rate was 86.3%. Multivariate analysis revealed lymphovascular invasion (LVI; p < 0.01) and max SUV ≥4.7 (p < 0.01) to be independent predictive factors. Patients with a max SUV more than 4.7 had a significantly high risk of recurrence. DFS of patients with high max SUVs and LVI (n = 18) was significantly reduced compared with other patients (n = 183, p < 0.01). The PET-CT results significantly correlated with recurrence in pathologic stage I lung cancers. Patients with high max SUVs and LVI were more likely to have recurrence and should be candidates for adjuvant chemotherapy.

Prognostic Significance of Positron Emission Tomography (FDG-PET) at Baseline and After 4 Cycles of R-CHOP in 75 Patients with Mantle Cell Lymphoma Treated with Intensive Chemotherapy and Autologous Stem Cell Rescue.

Abstract 1226Poster Board I-248 BackgroundThe value of FDG-PET in mantle cell lymphoma (MCL) has not been addressed in a homogeneous group of pts. The optimal initial therapy is controversial; however, intensified therapy followed by consolidation with high-dose therapy and autologous stem cell rescue (HDT-ASCR) is associated with superior progression-free survival (PFS) compared to CHOP-based therapy. In this study, we examined the prognostic value of FDG-PET in a group of uniformly treated pts with upfront HDT-ASCR consolidation. The role of FDG-PET was evaluated: at baseline; as a predictor of proliferation index (PI); and as interim evaluation after induction therapy prior to HDT-ASCR. Pts and MethodsPts received sequential therapy consisting of sequential R-CHOP-14 × 4 followed by RICE x 2-3 cycles and consolidation with HDT-ASCR. FDG-PET and diagnostic CT imaging was obtained at baseline and after R-CHOP (N=75). The number of cycles of RICE was determined by the PET and CT response after induction with R-CHOP-14×4; pts with FDG-avid disease received a third cycle. Additional therapy was administered in 10 pts who had persistent FDG-avid disease after RICE with the objective of achieving the best response prior to the HDT-ASCR. Therapy included bortezomib in 7 cases and other treatment in 3 cases. The PI was determined by quantitative image analysis of Ki-67 stained slides (N=39). The median follow-up was 3.4 years. ResultsThe median age was 59 years, 71% had bone marrow disease and 85% had stage 4 disease. According to the MIPI score, 50% had low-risk, 35% had intermediate-risk and 15% had high-risk disease. The baseline FDG-PET was positive in 71 pts (95%) and the median SUV was 5.5 (1.6-14). The baseline SUV was not prognostic after the stratification of the pts by the median SUV (PFS 81% vs 84% and overall survival (OS) 100% vs 74%, p=0.15). The median PI was 22% for the pts with an SUV below the median and 36% for the other group (P=0.03, Mann-Whitney). Interim FDG-PET evaluation after induction with R-CHOP-14 was available in 69 pts among the 71 with a positive test at baseline, the exam was negative in 49 pts (71%). A negative interim FDG-PET was associated with a better PFS (84% v 40% at 4years, p<0.0001) and a better OS (94% v 70% at 4 years, p=0.019). When FDG-PET results were added to response determined by CT scan, there was no difference in PFS between FDG-PET negative with either a CT CR (N=28) or CT PR (N=20) (91% vs 73% at 4 years, P=0.89). In contrast, patients with a CT PR had an inferior PFS and OS when the FDG-PET was positive (N=19) compared when the FDG-PET was negative (42% vs 76% at 4 years, P=0.008). The 4-year OS was 96% for FDG-PET negative CT CR, 91% for FDG-PET negative CT PR and 70% for FDG-PET positive CT PR (P=0.08). ConclusionsIn MCL, a baseline FDG-PET is useful as not all cases are positive. Though SUV correlates with the PI, the pretreatment SUV alone is not prognostic. Pts in PR by CT are separated by the FDG-PET result with negative pts having a superior outcome. The interim FDG-PET after induction with R-CHOP-14 × 4 is prognostic for PFS and OS in a program of sequential therapy with upfront consolidation with HDT/ASCR. DisclosuresNo relevant conflicts of interest to declare.

Positron emission tomography (PET) in the urooncological evaluation of the small pelvis

Positron emission tomography (PET) with the use of ((18)F)2-fluoro-D: -2-desoxyglucose (FDG) has been investigated to be a highly sensitive and specific imaging modality in the diagnostic of primary and recurrent tumors and in the control of therapies in numerous non-urologic cancers. The aim of this review is to validate the significance of PET as a diagnostic tool in malignant urological tumors of the small pelvis. A systematic review of the current literature concerning the role of PET for malignant prostate, testicular and bladder tumors was carried out. The data indicate no additional role for PET in comparison with conventional imaging in tumor detection and local staging for prostate, bladder or testicular cancer. Tumor recurrence in prostate cancer seems to be more effectively identified with acetate and choline than with FDG, but this effect is more pronounced with higher PSA values. The value of PET in the identification of metastatic disease in either tumor entity can not be finally outlined as the clinical data are partly missing, controversial or in the process of evaluation. FDG-PET can be regarded as accepted imaging modality in the restaging of seminomatous germ cell tumors after chemotherapy.

Significance of fluorodeoxyglucose PET imaging in the diagnosis of malignancies in patients with biliary stricture

Aim This study was performed to evaluate the significance of positron emission tomography using fluorodeoxyglucose (FDG-PET) in diagnosing malignancy in patients with biliary stricture by comparing the sensitivity and specificity of FDG-PET with those of CT scans and cytological examination of the bile. Methods Thirty patients who underwent FDG-PET for differential diagnosis of the disease causing biliary stricture were included in this study. The sites of the strictures were as follows: in the intrahepatic bile duct in five patients, in the peripheral extrahepatic bile duct in 17 patients, and in the distal extrahepatic bile duct in eight patients. The sensitivity and specificity (%) of FDG-PET in diagnosing malignancies were evaluated and compared with those of CT scans and cytological examination using obtained bile. Final diagnoses were based on surgical or biopsy findings. Data was collected and analysed in a retrospective fashion. Results Malignant diseases were diagnosed in 21 patients, as follows: cholangiocarcinoma including Klatskin tumour in 10 patients, gallbladder cancer in eight, duodenal and ampulla cancer in two, and pancreatic cancer in one. In diagnosing malignancy in patients with biliary stricture, overall sensitivity and specificity were 85.7 (18/21) and 55.6 (5/9), respectively, for CT, 64.7 (11/17) and 100 (7/7), respectively, for cytological examination of the bile, and 90.5 (19/21) and 77.8 (7/9), respectively, for FDG-PET. Conclusions In diagnosing malignant diseases in patients with biliary stricture, FDG-PET was superior to CT examination in both sensitivity and specificity, and superior to cytological examination of the bile in sensitivity. However, in patients with inflammatory disease, such as primary sclerosing cholangitis and cholecystitis, false positive rates were found. Therefore, a multidisciplinary diagnostic approach using FDG-PET in conjunction with conventional modalities seems essential to a precise differential diagnosis.

Prognostic significance of positron emission tomography using fluorine-18-fluorodeoxyglucose in patients treated for malignant lymphoma

To evaluate the prognostic significance of positron emission tomography (PET) using fluorine-18-[2]-fluoro-2-deoxyglucose (FDG) in patients treated for Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL) compared to conventional restaging (CRS). Fifty-six patients with either HD (n = 22), high-grade NHL (n = 26) or centrocytic-centroblastic NHL (n = 8) were included. PET was performed in 41 patients for treatment reevaluation up to three months after therapy and in patients with persisting residual masses (n = 10) or suspected relapse (n = 5) four to twelve months after treatment. The scans were evaluated qualitatively and quantitatively using standardised uptake values (SUV). Progression-free survival (PFS) was estimated to assess the prognostic value of FDG PET and clinical follow-up was taken as gold standard. PET was positive in nineteen of 41 patients studied for treatment reevaluation. Progression was observed after a median interval of two months (range 0-15) in sixteen of 19 patients after a positive PET scan and in three of 22 patients after a negative scan (p < .001). Median duration of follow-up in progression-free patients was 21 months (range 6-72). In patients with a partial remission in CRS progression was more common in PET-positive than in PET-negative patients (5 of 7 vs. 1 of 14; p < .01) and positivity with PET was associated with poorer PFS (p < .0025). PET studies performed four to twelve months after treatment were true negative in seven, true positive in five and false-positive in three patients. SUV > 11.35 of lymphoma lesions was associated with poorer PFS than SUV < 11.35 (p < 0.025). We conclude that FDG PET after treatment of malignant lymphoma has a high prognostic value and should be recommended in patients with persistence of residual masses.