Role Of PET Scan Research Articles

Role of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Detection of Portal Vein Tumor Thrombosis in Hepatocellular Carcinoma

A 56 year old gentleman with no known comorbidities presented with pain abdomen for 1 month. Triphasic CECT abdomen showed features of cirrhosis with surface irregularities, fissural widening and volume redistribution changes in the liver. Segment VII of liver showed an arterial enhancing lesion measuring 4.2 x 3.5cm showing washout in delayed phase. In view of BCLC A stage with Child Pugh B7, ablation was planned. Before proceeding with ablation, in view of very high alpha-fetoprotein (AFP) level of 9836 ng/mL, he was advised for metastatic evaluation with 18F-FDG PET-CT. The PET scan showed abnormal heterogeneous increased FDG uptake in segment VII of liver (SUV Max 4.7) with arterial enhancement and washout suggestive of metabolically active hepatocellular carcinoma. Also seen was an abnormal linear increased FDG uptake in right branch of portal vein (SUV Max 4.8) which was suggestive of portal vein invasion. In view of portal vein tumor thrombus, ablation procedure was deferred for the patient. Role of PET scan in HCC with vascular invasion is not yet defined. Poor specificity of FDG PET is the major hindrance in establishing PET scan as diagnostic tool for vascular invasion. In small segment invasion when CECT is not able to differentiate between tumour versus bland thrombus PET scan may be significant tool to differentiate between bland thrombus and tumour thrombus. Vascular invasion confirmation have treatment related and prognostic significance. There is a need for a prospective study evaluating the prognostic significance of PET scan based diagnosis of vascular invasion.

Role of Combined 68Ga DOTA-Peptides and 18F FDG PET/CT in the Evaluation of Gastroenteropancreatic Neuroendocrine Neoplasms.

This review article summarizes the role of combined 68Ga DOTA-peptides and 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the evaluation of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). Patients with GEP-NENs can initially present themselves to a gastroenterologist or endocrinologist rather than cancer specialist; hence, it is vital for a wider group of clinicians to be familiar with the range of tests available for the evaluation of these patients. The role of PET scanning by using 68Ga DOTA-peptides has a high sensitivity in the diagnosis of GEP-NENs and to guide patient selection for treatment with somatostatin analogues (SSA) and/or peptide receptor radionuclide therapy (PRRT). The loss of somatostatin receptor (SSTR) expression was found to be associated with an increased glucose metabolism in cells. However, the routine use of SSTR targeted radiotracers in combination with 18F-FDG to evaluate glucose utilization in GEP-NENs is still debatable. In our opinion, in patients with NENs, 18F-FDG PET should be performed in the case of a negative or slightly positive 68Ga DOTA-peptides PET scan for assessing the dedifferentiation status, to guide correct therapeutic strategy and to evaluate the prognosis. The approach of combined receptor and metabolic imaging can improve diagnostic accuracy, especially considering the heterogeneity of these lesions. Therefore, 68Ga DOTA-peptides and 18F-FDG PET should be considered complementary in patients with GEP-NENs.

Semi-ResMass Study: Residual masses after salvage chemotherapy in men with pure seminoma—A multicenter retrospective analysis.

420 Background: Only scarce data exist on the management of residual masses in men who have received two lines of chemotherapy for advanced seminoma. Due to the lack of data, the role of PET scanning, surgery and other additional treatments is controversial in these men. Methods: Data from men with pure seminoma and residual masses after salvage chemotherapy were retrospectively collected from 10 high-volume centers in 3 European countries. We analyzed the clinical management of residual masses (imaging, surgery, pathological data, and additional treatment modalities) and long-term outcomes. Residual mass was defined as a lesion of ≥1 cm after two lines of platin-based chemotherapy. Results: To date, data from 48 patients (pts) with non-progressing residual masses after second line (salvage) chemotherapy have been collected and are included in this analysis. Median age at diagnosis was 36 years (range 31; 42). A post-chemotherapy PET-FDG was performed in 32 (67%) pts. Surgery was performed in 20/48 (41%) pts irrespectively of FDG uptake (no, n=8; yes, n=5). Complete necrosis was found in 16 (80%), viable seminoma in 3 (15%), and teratoma in 1 pt, respectively. All pts with a negative PET (PET-) who underwent surgery (8/8) had complete necrosis. 5/11 pts with a positive PET (PET+) underwent surgery: 3 had a complete necrosis while 2 had viable seminoma. Among those with a PET+, 3 pts (28%) experienced either viable seminoma in residual masses or a subsequent relapse. The absence of FDG uptake correlated with absence of viable cancer (p=0.04). A second relapse occurred in 5/48 pts (10%). Only 2/20 pts who had residual masses resected post 1st salvage chemotherapy subsequently relapsed (one had viable seminoma in the residuals). At a median follow up of 4 years (IC95% [3.5-5.5]), 41/48 pts (87%) were alive. 7/48 patients died of cancer progression. Conclusions: Most men with residual masses after 1st salvage chemotherapy for advanced seminoma may achieve a cure. Pending validation with more pts in this rare situation, PET-FDG may help guide who should be selected for post-chemotherapy resection. Updated results will be presented at the congress.

AB024. The role of PET scan in differential diagnosis of extrapulmonary involvement in sarcoidosis

Methods: A 37-year-old woman presented with cough, fever and neurological symptoms (flashing lights, headache, transient paralysis of the right half of the face, gait instability, numbness in legs and swallowing disorders) with duration of four months.

Role of PET-CT scan in synchronous primary cancers of the upper aerodigestive tract: a case report

Oral field cancerization though not a new concept, has time and again, proven to be a challenge to the clinician, in terms of diagnosis and management. Prolonged exposure of the aerodigestive tract to carcinogens causes multifocal cancers. Intraepithelial migration of dysplastic or clonal cells becomes the seed for different primaries in the same field. The probability of synchronous malignancies should be borne in mind while evaluating a patient with head and neck cancer. With the advent of highly specific diagnostic tools like the PET scan, the chances of missing a second primary are eliminated/negligible. This is a case report on a patient who was found to have multiple primaries on clinical and radiological evaluation. Patient underwent multimodality treatment with chemoradiotherapy followed by surgery and is currently under follow-up. We aim to highlight the role of PET scanning in the evaluation of head and neck cancer to prevent missing a second primary.

The role of PET scans in the management of Cholangiocarcinoma and Gallbladder Cancer: A systematic review for surgeons

Introduction: Radical surgical resection is the only potentially curative therapy for cancers arising in biliary epithelia (gallbladder cancer and cholangiocarcinoma). Accurate radiological staging is crucial and the role of positron emission tomography-CT (PET-CT) scanning in this regard is undefined. Methods: A systematic review of the literature was carried out to define the accuracy of PET-CT in patients with cholangiocarcinoma or gallbladder cancer in defining metastatic disease in portal, and extra-portal lymph nodes, the presence of intra-hepatic satellite lesions, extra-abdominal metastases and recurrent disease in patients following treatment. Results were displayed in a narrative format with no meta-analysis feasible. Results & Conclusions: Four hundred and sixty eight records were screened, 49 were assessed and 12 studies were included in the systematic review. PET-CT has a low sensitivity for regional lymph node metastases from cholangiocarcinoma and gallbladder cancer but a high specificity. In one study, PET-CT appears to be effective in assessing all nodal basins related to the liver, bile ducts and gallbladder. PET-CT has no role in the assessment of hepatic satellite lesions but is useful in defining extra-abdominal metastatic disease and recurrent disease and to assess specific areas of concern defined on CT scan and/or magnetic resonance scan.

Role of PET Scan in Initial Staging of Oral Squamous Cell Carcinoma

The sensitivity of FDG-PET in detecting primary tumors of the head and neck has been extensively studied. Hannah et. al1reported a sensitivity of 88% for PET in the detection of known primary tumors and 51% for CT in detection of oral squamous carcinoma in their series. PETs are reported to be not as specific (75%)2 for follow up and re-staging. The goal of this study is to determine whether PET scans would change our surgical approach when comparing initial clinical staging with PET scan to final pathology.

Role of PET scan in predicting response to neoadjuvant chemotherapy and long-term outcomes for stage II lung cancer.

7574 Background: While the role of neo-adjuvant chemotherapy (NAT) in stage IIIA non-small cell lung cancer (NSCLC) is well established, its efficacy in stage II is unclear. We evaluated the role o...

18F-FDG PET Provides High-Impact and Powerful Prognostic Stratification in the Staging of Merkel Cell Carcinoma: A 15-Year Institutional Experience

Merkel cell carcinoma (MCC) is a rare but aggressive skin cancer with limited evidence on the role of PET scanning. The primary aim of this study was to assess the impact of (18)F-FDG PET in the staging and management of MCC. A single-institution review using clinical outcome data collected until February 2012 was performed of patients with MCC who underwent staging PET scanning between January 1997 and October 2010. Management plans were recorded prospectively at the time of the PET request, and follow-up outcomes were recorded retrospectively. The clinical impact of PET was scored using our previously published criteria: "high" if the PET scan changed the primary treatment modality or intent; "medium" if the treatment modality was unchanged but the radiation therapy technique or dose was altered. The primary objective was to test the hypothesis that the true proportion of patients who have a high- or medium-impact scan would be greater than 25%. The median follow-up of 102 consecutive patients was 4.8 y. The results of staging PET had an impact on patient management in 37% of patients (P < 0.003). High- and medium-impact scans were recorded for 22% and 15% of patients, respectively. PET staging results differed from conventional staging results in 22% of patients, with PET upstaging 17% and downstaging 5%. The 3- and 5-y overall survival was 60% (95% confidence interval, 50%-71%) and 51% (95% confidence interval, 41%-64%), respectively. In stratification by PET-defined stage, the 5-y overall survival was 67% for patients with stage I/II disease but only 31% for patients with stage III disease (log-rank P < 0.001). The 5-y cumulative incidence of locoregional failure, distant failure, and death was 16.6%, 22.3% and 14.3%, respectively. On multivariate analysis, only PET stage (P < 0.001) and primary treatment modality (P = 0.050) were significantly associated with overall survival. The primary treatment modality was not associated with progression-free survival when stratification was by tumor stage. The use of (18)F-FDG PET scans had a great impact on patients and may play an important role in the prognostic stratification and treatment of this disease.

Reply to Baisi et al.

We thank Baisi et al. [1] for their interest in, and comments on, our article [2]. First, all of the patients in this retrospective study underwent brain computed tomography (CT) or brain magnetic resonance imaging (MRI) to evaluate brain metastasis, and most underwent F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) for systemic screening to evaluate the N and the M parameters. For the small-sized pure ground glass opacities without solid component, PET scans were sometimes skipped. To our understanding, the current clinical TNM staging system, assessing tumour extent, is essentially based on morphological evaluation by means of chest X-ray, CT or MRI [3]. To date, the role of PET scan in TNM staging is supplemental. In this study, we tried a morphological approach to adenocarcinoma, and it may work well at least in the area of adenocarcinoma. We totally agree that the current TNM staging system is not totally affordable and, therefore, a more precise evaluation is required to predict survival. We know that adenocarcinoma includes a wide spectrum, and the biological behaviour of each subclass varies very much (i.e. adenocarcinoma in situ vs solid predominant invasive adenocarcinoma). By FDG-PET, tumour extent can be assessed precisely [4]. Moreover, previous studies clearly show that grading the FDG uptake may distinguish the intrinsic biological behaviour of the tumours, probably reflecting tumour pathology [5]. The application of FDG-PET for the evaluation of tumour aggressiveness seems to be a promising approach, however, the heterogeneity of PET techniques and performance and the difficulty of interinstitutional standardization are challenges in need of solutions [2, 5] before incorporating PET findings into TNM staging, particularly into the T-factor. The current TNM staging system involves of three-dimensional assessment. Adding new vectors reflecting biological factors (‘B-factor’: CEA level, FDG uptake, pathological grading, etc.) might be necessary for a new-generation system.

PET scans in HIV-related Hodgkin lymphoma (HIV-HL): Results of a retrospective study.

8044 Background: No data are available on using PET-scans in HIV-HL. The goal of the present study is to analyse consecutive patients (pts) with HIV-HL who had at least one PET scan conducted during their course of primary chemotherapy (CT). Methods: In the German prospective multicenter trial pts. with HIV-HL are planned to receive 2x ABVD + 30 Gy involved field (IF) radiation (RT) for early stage (ES) favourable HL (stage I/II without risk factors), 4x BEACOPP baseline or 4x ABVD + 30 Gy IF for ES unfavourable HL, and 6-8 x BEACOPP baseline for advanced stage HL with BEACOPP being replaced by ABVD in pts with far advanced HIV-infection or poor performance status. Since the role of PET-scans is not specifically addressed in this trial FDG-PET is not routinely scheduled. However, as PET-scans are being performed on physician’s choice we retrospectively analyzed results and clinical impact of FDG-PET in this cohort of pts. Results: From 03/04 to 12/10 105 pts (median age 43.9 yrs, 8 females) were included ...

120 Role of PET scanning in upstaging of small cell lung cancer (SCLC)

120 Role of PET scanning in upstaging of small cell lung cancer (SCLC)

Imaging of knee osteoarthritis

The use of MRI in studies of osteoarthritis (OA) is becoming increasingly common. Its benefit over radiography relate to its enhanced ability to identify structural changes prior to the presence of radiographic disease. Although cartilage loss is the hallmark of OA, it is clear that OA is a disease of the whole joint. MRI is able to directly visualize the whole joint in vivo, including articular cartilage, the menisci, the synovium and subchondral bone abnormalities. Using MRI, studies are beginning to explain the relationships between traditional and novel risk factors for OA, demonstrating how they influence changes in knee structure from early/pre-OA through to established disease. Other imaging modalities, such as ultrasound, may provide complementary approaches for the assessment of synovitis. The role of PET scanning is still unclear but, as with computed tomography, this may be used as an alternative when MRI is contraindicated.

The Role of PET scan in melanoma management

The Role of PET scan in melanoma management

Pancreatic cancer: ESMO Clinical Recommendations for diagnosis, treatment and follow-up

Staging consists of complete history and physical examination, blood counts, liver enzymes, chest X-ray, imaging of the abdomen by sonography and CT scan or magnetic resonance, and possibly by endosonography. Patients with pancreatic cancer may be staged according to the TNM system and can be grouped as shown in the table below. However, the distinction of whether or not a tumor remains resectable is not well reflected in the TNM system, as demonstrated by the wide range of survival figures given for each stage. Evaluation of resectability often requires surgery, preferably by staging laparoscopy, to exclude clinically occult intraabdominal and lymph node metastases. To be resectable, tumors must show no evidence of extrapancreatic disease or direct tumor extension to the celiac axis and superior mesenteric artery but evidence of nonobstructive superior mesenteric–portal vein confluence does not always preclude tumor resection. Less than 20% of all patients have resectable disease. treatment of resectable tumors

Value of FDG-PET for detecting metastatic lesions in head and neck cancer

6047 Introduction: The role of PET scans in the staging of head and neck cancer (HNC) is unclear. The NCCN guidelines do not recommend routine metastatic workup beyond physical exam, CXR and laboratory tests. The purpose of this report is to examine the incidence and accuracy of staging PET scans for detecting metastatic disease in patients with HNC. Methods: Retrospective review of all newly diagnosed HNC patients who had a staging PET scan at Thomas Jefferson University between 2003 and 2007. 182 patients with SCC (171), or adenocarcinoma (11) histologies were analyzed in this study, none of whom had known metastatic disease prior to staging PET exam. Clinical stage prior to the PET scan was stage I-II in 26 patients (14%), stage III in 24 patients (14%), and stage IVa or b in 107 patients (59%). 25 patients had recurrent disease. Results: The overall incidence of confirmed metastatic disease in this study population was 6.0%. Twenty-five (13.5%) of the staging PET scans had areas suspicious for a metastatic lesion(s). Twenty-two patients were further evaluated with subsequent confirmatory imaging and/or biopsy, revealing 10 (45.5%) true positives, and 12 (54.5%) false positives. Of the 157 negative PET scans there was 1(0.5%) false negative and 156 (98.7%) true negatives. Thus, the sensitivity of PET was 91% and specificity was 93%. Positive predictive value is 45% and negative predictive value is 99.5%. No patients with pre-PET clinical stage II or I cancer had confirmed distant metastases. Patients with metastatic disease had stage III (1 patient) or stage IV (10) - nodal stages were N0 (2), N2 (1), N2 (4), and N3 (3). The only statistically significant predictor for metastatic disease was clinical stage IV versus all other stages (p <0.028). Conclusions: The incidence of metastatic disease in HNC is low, but finite. Given the marked differences in the treatment of locally advanced/non-metastatic HNC versus metastatic HNC, we recommend metastatic workup with PET for clinical stage III/IV disease. Although the sensitivity, specificity and negative predictive value rates were acceptable, the positive predictive value was suboptimal. Patients found to have a PET scan ‘positive‘ for metastatic disease require confirmatory imaging or ideally biopsy. PET scan is not necessary for patients with clinical stage I/II disease. No significant financial relationships to disclose.

Papers Presented at the 2005 Meeting of the Musculoskeletal Tumor Society

Papers Presented at the 2005 Meeting of the Musculoskeletal Tumor Society

Giant cell arteritis mimicking fever of unknown origin: potential diagnostic role of PET scan

Giant cell arteritis mimicking fever of unknown origin: potential diagnostic role of PET scan -

The role of PET scan in the preoperative management of oesophageal cancer

The role of PET scan in the preoperative management of oesophageal cancer

The Role of PET Scan in Diagnosis, Staging, and Management of Non-Small Cell Lung Cancer

Positron emission tomography (PET) is now an important cancer imaging tool, both for diagnosis and staging, as well as offering prognostic information based on response. This report attempts to comprehensively review the value of PET in the locoregional and distant staging of non-small cell lung cancer (NSCLC), illustrate the potential effects on patient management, and give a short overview of newer applications. PET sets the gold standard in the evaluation of an indeterminate solitary pulmonary nodule or mass, where PET has proven to be significantly more accurate than computed tomography (CT) in the distinction between benign and malignant lesions. In the evaluation of metastatic spread to locoregional lymph nodes, PET is significantly more accurate than CT, so that invasive surgical staging may be omitted in many patients with negative mediastinal PET images. In patients with positive mediastinal PET images, invasive surgical staging remains mandatory because of the possibility of false-positive findings due to inflammatory nodes or granulomatous disorders. In the search for metastatic spread, PET is a useful adjunct to conventional imaging. This may be due to the finding of unexpected metastatic lesions or due to exclusion of malignancy in lesions that are equivocal on standard imaging. However, at this time, PET does not replace conventional imaging. Large-scale randomized studies are currently examining whether PET staging will actually improve the appearance of lung cancer outcome.