Role Of FDG PET-CT Research Articles

Role of F-18 FDG PET-CT in neuropsychiatric systemic lupus erythematosus

BackgroundNeuropsychiatric systemic lupus erythematosus (NPSLE) is a major contributor to morbidity and mortality in systemic lupus erythematosus (SLE) patients. To date no single clinical, laboratory or imaging test has proven accurate for NPSLE diagnosis which is a testament to the intricate and multifactorial pathophysiological mechanisms suspected to exist. Functional imaging with FDG PET-CT has shown promise in NPSLE diagnosis, detecting abnormalities prior to changes evident on anatomical imaging. Research indicates that NPSLE may be more aggressive in people of African descent with higher mortality rates, making rapid and correct diagnosis even more important in the African context. MethodsIn this narrative review, we provide a thorough appraisal of the current literature on the role of FDG PET-CT in NPSLE. Large, well-known databases were searched using appropriate search terms. Manual searches of references of retrieved literature were also included. FindingsA total of 73 article abstracts were assessed, yielding 26 papers that were directly relevant to the topic of FDG PET-CT in NPSLE. Results suggest that FDG PET-CT is a sensitive imaging test for NPSLE diagnosis and may play a role in assessing treatment response. It is complementary to routine anatomical imaging, particularly in diffuse manifestations of the disease. Newer quantitative analyses are commonly used for interpretation and can detect even subtle abnormalities, missed on visual inspection. Findings of group-wise analyses of FDG PET-CT scans in NPSLE patients are important in furthering our understanding of the complicated pathophysiological mechanisms involved. Limitations of FDG PET-CT include its lack of specificity, high cost and poor access. ConclusionFDG PET-CT is a sensitive test for NPSLE diagnosis but is hampered by lack of specificity. It is a valuable tool for clinicians managing SLE patients, particularly when anatomical imaging is negative. Its exact application will depend on the local context and clinical scenario.

Spectrum of autoimmune limbic encephalitis on FDG PET/CT

To evaluate the role of FDG PET CT in the management of patients with suspected autoimmune encephalitis (AE). A retrospective analysis of 27 patients of clinically suspected cases of AE, who underwent FDG PET CT, was done. The patterns of FDG uptake in different antibody subtypes were recorded and comparison with normalized data was attempted. Post treatment follow-up scans were also acquired and analyzed. Focal areas of hypermetabolism involving medial temporal regions, basal ganglia and thalami with relative global hypometabolism, both on visual inspection and on semiquantitative analysis. Serologically, 17 patients had antibodies against Voltage gated potassium channel (VGKC) complex /LGI1 receptors, 2 had antibodies against CRMP-5 (Anti-CV-2) and 1 had had antibodies against PCA-1/Anti-Yo receptor. We could not isolate the antibody in 7 seven patients. Suspicious mitotic lesions were identified in 10 patients on the whole body scan, which later were biopsied and characterized. No scan evidence of mitotic pathology was identified in 17 patients, thus were labeled as non para neoplastic. Focal hypermetabolism was found to be a feature of acute phase, whereas hypometabolic areas were seen in sub acute and chronic phases of the disease. On follow-up, the post-treatment FDG PET CT scans obtained in some of these patients showed reversal to normal metabolism in the corresponding areas. FDG PET CT may have an important role both in the identification of AE itself and in the detection of the unknown malignancy that might have caused it.

Role of FDG-PET CT in the Management of Muscle Invasive Bladder Cancer

Role of FDG-PET CT in the Management of Muscle Invasive Bladder Cancer

Role of FDG PET-CT in Distinction of Benign Thrombus and Tumor Thrombus in Oncological Patients

Accurate diagnosis of tumor thrombus and distinguishing benign thrombus from tumor thrombus avoid unnecessary anticoagulant...

The potential role of FDG PET-CT in the characterization of the activity of Crohn’s disease, staging follow-up and prognosis estimation: a pilot study

Objectives: FDG PET-CT is a global, noninvasive, sensitive method to determine the location and activity of inflammatory lesions. Segmental FDG uptake is proportional with immune cell infiltration of bowel. Our aim was to evaluate prospectively the role of PET in patients with active Crohn’s disease (CD) before and after one year’s biological therapy, and to compare simple endoscopic score for CD (SES-CD), CD activity index (CDAI) and global PET scores. We also analyzed the prognostic value of initial PET scores.Patients: Twelve patients were selected: six male/six female, ages between 18 and 39, average: 24 years, with CDAI values >300.Methods: We scored the FDG uptake in the small intestine and the four colon segments (on a scale 0–3 for each), and summed them thus forming a global PET score. The scoring was based on the maximal standardized uptake value of the intestinal segment, related to the SUVmax of the liver (as a reference for normal tissue activity). The SES-CD, CDAI and global PET scores before and after treatment were statistically compared.Results: There were significant changes in CDAI and SES-CD after therapy, PET scores improved only in patients’ subgroup with high (>4) initial PET score, indicating good prognosis of biological treatment. In active disease, PET was more informative than endoscopy to access the extent of the inflammation, and small intestine involvement.Conclusions: FDG PET-CT score is a promising, noninvasive complementary method in the staging, treatment planning and follow-up of CD. Limitation of the study is the small number of patients.

Role of fluorodeoxyglucose positron emission tomography-Computed tomography in thyroid malignancy

The role of FDG PET CT in thyroid malignancy is not clearly established. Malignancy of the thyroid remains poses issues very different from the squamous carcinomas of the upper aerodigestive tract where PET-CT is usually used. Though this is the most common endocrine malignancy, many a times it is difficult to diagnose malignancy in thyroid nodules. The biology of well differentiated thyroid cancer, medullary carcinoma, poorly differentiated carcinoma and anaplastic carcinoma varies significantly and management strategies differ dramatically. FDG PET can be used as a wonderful tool in thyroid malignancy for selected indications.

EP-1095: Prognostic role of FDG PET-CT performed before and during radiotherapy for nasopharyngeal cancer

EP-1095: Prognostic role of FDG PET-CT performed before and during radiotherapy for nasopharyngeal cancer

402 FDG PET-CT vs CT scan in the staging of urothelial neoplasms

INTRODUCTION AND OBJECTIVES: Thoracic and abdominal CT scan remains the gold standard for staging of urothelial carcinoma. No prospective trials have adequately assessed the role of FDG PET-CT. METHODS: From May 2011 to April 2015, we prospectively collected data of 47 patients referred to the hospital for treatment of either bladder or upper urinary tract tumors and staged by CT as surgical candidates with localized or locally advanced disease. PET-CT was performed either before neoajuvant or adjuvant chemotherapy for final clinical staging. RESULTS: Median age was 68 years (47-87), 87% (41) were men. 41 patients (87%) had bladder cancer, 5 an upper urinary tract tumor (10%) and 1 patient had a cancer of the urethra (2%). Histology was urothelial in 45 cases (96%) and squamous in 2 (4%).Median time fromCT to PET-CTwas1.7months (0.33-5.87). PET-CTwasdonebefore taking final therapeutic decision in 27 cases (57.4%), and after surgery in 20 (42.6%). Overall, discrepancies between CT and PET were seen in 26/47 cases (55%), implicating a change in the recommended treatment of 19 patients (40%). PET-CT identified unknown visceral metastases in 16 patients (34%); of them 5 patients had thoracic metastases (31%), 6 extrathoracic (38%), and 5 had both (31%). For patients referred for neoadjuvant chemotherapy, 11/27 patients (40%) were restaged as M1 by PET-CT. For patients referred for adjuvant chemotherapy, 8/20 (40%) patients had metastatic disease detected by PET-CT (3 nodal, 5 visceral). Final Staging by CT vs PET was as follows: II on 36% vs 28%, III on 15% vs 10%, IV on 49% vs 62%. From the 32 patients (66%) who had finally surgery, pathological stage was II on 7 (23%), III on 8 (26%) and IV on 16 (52%). CONCLUSIONS: In our experience, FDG PET-CT in urothelial cancer not only provided additional prognostic information compared to CT, but also changed management of patients.

Correlation of FDG-PET-CT with Bone Marrow Aspiration and Biopsy at the Initial Staging in Follicular Lymphoma: Can We Omit Bone Marrow Biopsy in Some?

Introduction: The role of FDG PET-CT in follicular lymphoma is limited to accurate assessment of disease extent in early stage patients and selection of biopsy site in cases of suspected high- grade transformation. Despite the known FDG avidity of follicular lymphoma, FDG PET-CT has not yet been included as part of standard staging procedures in these patients. FDG PET-CT has shown significant correlation with bone marrow biopsy in Hodgkin and diffuse large B-cell lymphomas. In this retrospective analysis we have assessed the correlation of PET-CT with that of bone marrow biopsy, the reference standard for assessment of bone marrow infiltration in follicular lymphoma.Methods: We retrospectively analyzed electronic medical records and database of patients with newly diagnosed follicular lymphoma registered at Tata Memorial Centre from July 2009 to Jun 2014, who underwent complete staging workup as per the current recommendations along with whole body 18FDG-PET/CT. The demographic features, performance status, stage, LDH, nodal sites, haemoglobin, follicular lymphoma international prognostic index (FLIPI), FDG PET-CT findings (bone marrow involvement, pattern of involvement- focal or diffuse, sites of marrow involvement, liver and spleen uptake, SUVmax of most FDG avid lesion) and bone marrow aspiration/biopsy (morphology, immunohistochemistry and immunophenotyping on aspirate, where available) findings were recorded. Focal uptake in marrow on baseline PET-CT was considered as marrow involvement if post therapy PET-CT showed resolution of these lesions. The sensitivity, specificity, negative and positive predictive value of PET-CT in detecting bone marrow infiltration was assessed taking bone marrow biopsy as gold standard. The factors responsible for discordant results were analyzed.Results: A total of 54 patients (males-38, females-16) were included in analysis with median age of 50 years, (range 22-73 years). At diagnosis 83% (45 patients) had stage III or IV disease and 57% patients had high-risk FLIPI score. Approximately 88% patients had good performance status (ECOG-<2). Bone marrow showed infiltration in approximately 60% (32 patients) on biopsy and immunophenotyping. PET-CT showed bone marrow involvement in 18 patients (focal-12, diffuse -6). In 4 patients with focal PET-CT positivity, bone marrow was uninvolved. However, post therapy these lesions showed resolution, thus confirming the presence of disease pretherapy. The sensitivity, specificity, positive and negative predictive value of PET/CT with respect to biopsy was 43.7%, 81.2%, 77.8% and 50% respectively. However, if we include the above mentioned 4 cases as true positives, then specificity and positive predictive value improves to 100% each. In addition, PET-CT could accurately predict absence of bone marrow involvement in stage I and stage II disease (100% concordance). The median SUVmax of most FDG avid lesion was 13.1 (5.25-34.93). However the SUVmax did not correlate with grade of lymphoma as the node biopsy was not done based on PET-CT results.Conclusion: This study shows that in patients with advanced stage follicular lymphoma bone marrow biopsy can be omitted if PET-CT shows focal or diffuse bone marrow uptake. Similarly, patients with early stage disease with no bone marrow uptake on PET-CT can be spared from bone marrow biopsy. DisclosuresNo relevant conflicts of interest to declare.

PET/CT in lymphoma surveillance: A large single-center experience.

8569 Background: The role of FDG PET-CT in the modern management of lymphoma continues to evolve. Current guidelines are largely based on studies with limited numbers of patients. The aim of this s...

Rising serum thyroglobulin in the follow-up of patients with differentiated thyroid carcinoma: the role of FDG PET-CT

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Role of FDG PET-CT in evaluation of locoregional nodal disease for initial staging of breast cancer.

Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is not indicated or recommended in the initial staging of early breast cancer. Although it is valuable for detecting distant metastasis, providing prognostic information, identifying recurrence and evaluating response to chemotherapy, the role of FDG PET/CT in evaluating locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. FDG PET/CT has high specificity but compromised sensitivity for identifying axillary nodal disease in breast cancer. Positive axillary FDG PET/CT is a good predictor of axillary disease and correlates well with sentinel lymph node biopsy (SLNB). FDG PET/CT may help to identify patients with high axillary lymph node burden who could then move directly to axillary lymph node dissection (ALND) and would not require the additional step of SLNB. However, FDG PET/CT cannot replace SLNB or ALND due to unsatisfactory sensitivity. The spatial resolution of PET instruments precludes the detection of small nodal metastases. Although there is still disagreement regarding the management of internal mammary node (IMN) disease in breast cancer, it is known that IMN involvement is of prognostic significance, and IMN metastasis has been associated with higher rates of distant metastasis and lower overall survival rates. Limited clinical observations suggested that FDG PET/CT has advantages over conventional modalities in detecting and uncovering occult extra-axillary especially IMN lesions with upstaging the disease and an impact on the adjuvant management.

Abstract 4695: Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule.

Abstract Objectives : We have shown that pathological regression of LARC and relapse free survival can be predicted by early changes in FDG uptake during preoperative radiochemotherapy. We have attempted to improve efficacy of our neo-adjuvant treatment by adding an experimental bevacizumab (BEV) schedule. FDG PETCT was utilized to monitor response and correlate with pathological outcome. Methods : Forty six patients with poor prognosis LARC received 3 biweekly courses of oxaliplatin/ raltitrexed (day 1) and FU/ folinic acid (day 2) during pelvic RT (45 Gy). BEV (5 mg/kg) was administered on day -4 for the first 2 courses. PET-CT was performed at baseline, on day 12 and prior to surgery and lesion TLG (mean SUV x volume) values determined. Pathologic response was defined using a modified Mandard tumor regression grade (TRG) scale. Responders were defined as TRG1-2, non-responders as TRG3-4. Results : Thirty-seven patients (80%) showed pathologic response (65% with previous scheme). Eight patients (17%, previously 35%) were non-responders. Responders showed significantly higher TLG reduction on day 12 PET-CT (median -72% range -90%+31%) compared to non-responders (TRG3-4, median -38%, range -45% +25%, p &amp;lt; 0.05), confirming previous findings. Preoperative PET-CT studies, on the other hand, were not predictive of pathologic response (responders TLG change median -92%, range -100% +4%, non-responders median 86%, range -94%-76%, p = ns). Ongoing studies to define a correlation between FDG uptake and biomarkers of angiogenesis such as Circulating endothelial cells (CEC) will be presented. Conclusions : Our findings indicate that the current scheme significantly increases pathologic response. PET-CT confirms to be a powerful early surrogate marker of treatment efficacy. PET-CT may be used to tailor more aggressive treatment for non-responsive patient Citation Format: Antonio Avallone, Paolo Delrio, Biagio Pecori, Fabiana Tatangelo, Elena Di Gennaro, Antonella Petrillo, Vincenzo Rosario Iaffaioli, Alessandra Leone, Corradina caracò, Alfredo Budillon, Secondo Lastoria, Luigi Aloj. Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4695. doi:10.1158/1538-7445.AM2013-4695

OP-35 The role of FDG PET-CT in the preoperative work up of colorectal liver metastasis

OP-35 The role of FDG PET-CT in the preoperative work up of colorectal liver metastasis

The role of FDG PET-CT in differential diagnosis of pleural pathologies

ObjectiveThis study has aimed to evaluate the impact of F18 Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET-CT) in the differential diagnosis of malignant and benign pleural lesions in patients with suspected malignant pleural mesothelioma (MPM). Material and methodsFifty patients (32 females, 18 males; age range 24–79 years) with pleural thickening, fluid, plaques or calcification on previous CT scan were examined with FDG PET-CT. PET-CT imaging was obtained 1h after FDG injection. In 12 patients, delayed imaging from the thoracic region was performed 2h after injection. FDG uptake was evaluated visually and semiquantitively using standardized uptake value (SUV). FDG PET-CT findings were compared with histopathologic diagnosis. ResultsThirty-nine patients had increased FDG uptake in pleural lesions but PET-CT results were negative in 11 patients. When compared with histopathological results in FDG positive group, 34 patients had MPM, 5 had benign pathology; in FDG negative group 8 patients had benign pathology, 3 had MPM. Of patients with delayed imaging, 9 showed increased SUV but 3 had a decreased SUV on delayed images. Increased SUV group had 4 MPM, 5 benign pathology (3 chronic granulomatous inflammation, 2 benign asbestotic plaque). Decreased SUV group all had benign pathology (fibrosis, chronic inflammation, myofibrosis). DiscussionFDG PET-CT is a useful imaging modality in differential diagnosis of malignant and benign pleural lesions. Delayed imaging seems to be useful if there is a decrease in SUV suggesting a benign pathology but does not seem to contribute to the differential diagnosis if the SUV is increased.

Value of Magnetic Resonance and 18FDG PET-CT in Predicting Tumor Response and Resectability of Primary Locally Advanced Cervical Cancer After Treatment With Intensity-Modulated Arc Therapy

To report on the value of magnetic resonance imaging (MRI) and 2-deoxy-2-[18] fluoro-D-glucose positron emission tomography computed tomography (¹⁸FDG PET-CT) in predicting resectability and pathological response of primary locally advanced cervical cancer after neoadjuvant intensity-modulated arc therapy (IMAT) with or without cisplatin (C). Twenty-seven patients with International Federation of Gynecology and Obstetrics stages IB2 to IVA cervical cancer were treated with IMAT-C followed by extrafascial hysterectomy (EH). All patients received MRI and ¹⁸FDG PET-CT after IMAT-C. The end points of this study were to: 1. Assess the ability of MRI to predict negative surgical margins (R0). 2. Assess the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MRI in predicting the following situation at the EH specimen: "no residual disease or minimal microscopically visible residual tumor." 3. Assess the sensitivity, specificity, PPV, and NPV value of ¹⁸FDG PET-CT in predicting "no residual viable tumor cells" at the EH specimen. An R0 resection was obtained in all patients. None of the EH specimens contained macroscopically visible tumor. In 13 patients, no viable tumor cells were found and only 14 had residual microscopic disease. Twenty-four of 27 MRIs were able to correctly predict R0 resection. A negative MRI was 100% predictive for the end point "R0 resection." The specificity and NPV of MRI (end point 2) were 74% and 100%, respectively. No sensitivity or PPV could be calculated. The sensitivity, specificity, PPV, and NPV of ¹⁸FDG PET-CT were 29%, 62%, 44%, and 44%, respectively (end point 3). A negative MRI after IMAT-C predicts 100% correctly for R0 resection. The role of FDG PET-CT in predicting viable tumor cells at EH specimen is at least debatable.

The role of FDG PET-CT in differential diagnosis of pleural pathologies

ObjectiveThis study has aimed to evaluate the impact of F18 Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET-CT) in the differential diagnosis of malignant and benign pleural lesions in patients with suspected malignant pleural mesothelioma (MPM). Material and methodsFifty patients (32 females, 18 males; age range 24–79 years) with pleural thickening, fluid, plaques or calcification on previous CT scan were examined with FDG PET-CT. PET-CT imaging was obtained 1h after FDG injection. In 12 patients, delayed imaging from the thoracic region was performed 2h after injection. FDG uptake was evaluated visually and semiquantitively using standardized uptake value (SUV). FDG PET-CT findings were compared with histopathologic diagnosis. ResultsThirty-nine patients had increased FDG uptake in pleural lesions but PET-CT results were negative in 11 patients. When compared with histopathological results in FDG positive group, 34 patients had MPM, 5 had benign pathology; in FDG negative group 8 patients had benign pathology, 3 had MPM. Of patients with delayed imaging, 9 showed increased SUV but 3 had a decreased SUV on delayed images. Increased SUV group had 4 MPM, 5 benign pathology (3 chronic granulomatous inflammation, 2 benign asbestotic plaque). Decreased SUV group all had benign pathology (fibrosis, chronic inflammation, myofibrosis). DiscussionFDG PET-CT is a useful imaging modality in differential diagnosis of malignant and benign pleural lesions. Delayed imaging seems to be useful if there is a decrease in SUV suggesting a benign pathology but does not seem to contribute to the differential diagnosis if the SUV is increased.

The role of FDG PET-CT in the therapeutic evaluation for HNSCC patients

F-18 FDG PET/CT has been widely used to diagnose primary tumors and lymph node metastases and to evaluate the response of head and neck squamous cell carcinoma (HNSCC) to therapy. The advantage of using PET/CT is that this combination allows metabolic information to be precisely overlapped with anatomical information, thereby improving the identification of sites with an abnormal accumulation of F-18 FDG. The role of FDG PET/CT in the therapeutic evaluation (such as in treatment planning, the therapeutic response, and the surveillance and examination of HNSCC patients) is discussed in this manuscript. When evaluating the post-treatment outcome via FDG PET/CT, it is important to exclude the post-treatment inflammation-related increase in glucose metabolism in lymph nodes, salivary gland, muscles, and soft tissues. The influence of inflammation can be eliminated if PET/CT is performed after 12 weeks, by which time post-treatment inflammation subsides. Further, FDG PET/CT affords a high negative predictive value. Based on the results of an FDG PET/CT test, some invasive tests that are performed to detect recurrence can be omitted.

Role of FDG PET-CT in detecting recurrence in patients with uterine sarcoma

The purpose of the present study was to evaluate the role of 18F-fluorodeoxyglucose (FDG) PET-CT in detecting recurrent disease in posttherapy patients of uterine sarcoma and compare the same with conventional imaging (CI). A total of 15 FDG PET-CT studies were acquired in 12 posttherapy uterine sarcoma patients. The images were evaluated by two experienced nuclear medicine physicians in consensus. Clinical/imaging follow-up (minimum 6 months) and histopathology were taken as the reference standard. All the patients had also undergone CI (CT or MRI or ultrasonography) of the chest, abdomen, and pelvis. The diagnostic accuracy of FDG PET-CT was calculated and compared with that of CI. The median age of the patients was 51.5 years (interquartile range: 47.5-53). Histopathology was leiomyosarcoma in six, carcinosarcoma in five, and endometrial stromal sarcoma in one patient. Six FDG PET-CT studies were carried out for suspected recurrence and nine for posttherapy surveillance. Six FDG PET-CTs were positive and nine were negative for recurrence. The sensitivity, specificity, and accuracy of FDG PET-CT were 85.7, 100, and 93.3%, respectively, on per study-based analysis, and 80, 100, and 83.3% on per lesion-based analysis. PET-CT showed higher sensitivity and specificity compared with CI for both study-based and lesion-based analysis. However, no significant difference was found between FDG PET-CT and CI either in the study-based or in the lesion-based analysis (P not significant). FDG PET-CT is a highly sensitive and specific modality for detecting recurrence in posttherapy patients with uterine sarcoma. However, it provides no significant advantage over CI for this purpose.

The role of fdg-pet ct in colorectal cancer

The role of fdg-pet ct in colorectal cancer