Efficacy of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans in diagnosis of pulmonary nodules

To evaluate the value of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans, we performed FDG-PET scans in 23 patients with indeterminate pulmonary nodules less than 3 cm in size and analyzed these scans qualitatively and semiquantitatively. Histologie specimens were obtained by thoracoscopic excisional biopsy in 16 patients, CT-guided needle aspiration cytology in three, and bronchoscopic brushing cytology in four. Pathological diagnoses were lung cancer in 16 patients, benign inflammation in six, and malignant lymphoma in one. Sensitivity, specificity and accuracy of the FDG-PET scans were 88% (15/17), 67% (4/6) and 83% (19/23), respectively. There were two false-positive cases (organizing pneumonia and cryptococcosis) and two false-negative ones (slow-growing adenocarcinoma and malignant lymphoma). Although a few false-positive cases of granulomatous disease were yielded, the FDG-PET scans were highly sensitive in the detection of lung cancer. We conclude that the FDG-PET scanning in a useful diagnostic imaging modailty in the management of indeterminate pulmonary nodules.     

Efficacy of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans in diagnosis of pulmonary nodules]

To evaluate the value of F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scans, we performed FDG-PET scans in 23 patients with indeterminate pulmonary nodules less than 3 cm in size and analyzed these scans qualitatively and semiquantitatively. Histologic specimens were obtained by thoracoscopic excisional biopsy in 16 patients, CT-guided needle aspiration cytology in three, and bronchoscopic brushing cytology in four. Pathological diagnoses were lung cancer in 16 patients, benign inflammation in six, and malignant lymphoma in one. Sensitivity, specificity and accuracy of the FDG-PET scans were 88% (15/17), 67% (4/6) and 83% (19/23), respectively. There were two false-positive cases (organizing pneumonia and cryptococcosis) and two false-negative ones (slow-growing adenocarcinoma and malignant lymphoma). Although a few false-positive cases of granulomatous disease were yielded, the FDG-PET scans were highly sensitive in the detection of lung cancer. We conclude that the FDG-PET scanning in a useful diagnostic imaging modailty in the management of indeterminate pulmonary nodules.     

F-18]-fluorodeoxyglucose (FDG) positron emission tomography (PET) as a diagnostic for hip endoprosthesis loosening

AIM: The purpose of this study was to examine the FDG-PET in respect of its diagnostic valency with regard to septic/aseptic loosening of lower limb prostheses. METHOD: 28 patients with 41 lower limb prostheses were examined by means of FDG-PET to evaluate septic/aseptic loosening of their hip prostheses. Therefore, a differentiated FDG-PET result interpretation subdivided into five categories was developed. The final diagnosis was based on operative findings with following culture and histological outcome. RESULTS: The worked-out categories showed a high agreement to the intraoperative macroscopic and histological results (n = 23 correctly positive, n = 1 false positive, n = 1 correctly negative and n = 3 false negative). CONCLUSION: With a subtly differentiated interpretation (categories I - V) of the qualitative glucose metabolism safe statements can be made regarding septic/aseptic endoprostheses loosening. This was impressively confirmed by the agreement of the FDG results with the histological results.     

Detection of osteomyelitis using FDG and positron emission tomography

A positron emission tomography (PET) scan with 2-[fluorine-18]fluoro-2-deoxy-D-glucose ((18)FDG) was performed on a patient with clinical and laboratory signs of infection after a removed hip prosthesis but with indistinct signs on the bone scan and radiographs. The PET scan confirmed the clinical and laboratory signs and revealed an unidentified focus of infection in the distal area of the right femur.     

Potential usefulness of 18F-2-fluoro-deoxy-D-glucose positron emission tomography in cervical compressive myelopathy.

STUDY DESIGN: This case study describes the usefulness of high-resolution 18F-2-fluoro-deoxy-D-glucose (18FDG)-positron emission tomography (PET) for metabolic neuroimaging of the cervical spinal cord in patients with compressive myelopathy. OBJECTIVE: To examine whether 18FDG-PET imaging could visualize deterioration of cervical spinal cord function associated with a variable degree of compression and to determine its potential usefulness during assessment of myelopathy. SUMMARY OF BACKGROUND DATA: A few studies have described the use of 18FDG-PET imaging in cervical cord diseases, but visualization of the cervical spinal cord before and after surgical decompression for compressive myelopathy has not been reported. The potential usefulness of 18FDG-PET imaging for assessment of the function of compressed cervical cord has not been discussed previously. METHODS: An 18FDG-PET scan was performed before and after surgery in seven patients with cervical compressive myelopathy. The correlation between the metabolic rate of glucose of the cervical spinal cord and neurologic scores was evaluated. The metabolic rate of glucose in different vertebral levels was also measured. RESULTS: Preoperative metabolic rate of glucose was high in two patients but low in the other five. At the time of the second postoperative examination, metabolic rate of glucose was higher in six of the seven patients, and the increase was associated with neurologic improvement. Use of 18FDG was not related to changes in signal intensities on T2-weighted magnetic resonance images. The metabolic rate of glucose decreased at the affected vertebral level in four patients, increased in two, and did not change in one, relative to the unaffected levels. CONCLUSIONS: High-resolution 18FDG-PET neuroimaging may provide clinically useful qualitative and quantitative estimation of impaired metabolic activity of the compromised cervical spinal cord in compressive myelopathy. 18FDG-PET images may also offer additional information related to neuronal dysfunction induced by mechanical compression.     

The value of FDG positron emission tomography in the management of patients with breast cancer

Increasing experience with positron emission tomography (PET) scanning in breast cancer patients is revealing a significant role for this imaging modality. This report summarizes the experience of 2-[F18]fluoro-2-deoxy-D-glucose (FDG) PET scanning in 165 breast cancer patients from the BC Cancer Agency, British Columbia, Canada, and reviews the literature on this topic. Using the database at PETSCAN Vancouver, we identified imaged patients with a diagnosis of breast cancer. We then conducted a retrospective review of these patients' BC Cancer Agency charts to extract demographic and follow-up information. Between November 2000 and March 2003 we identified 165 patients with histologically confirmed breast cancer who had undergone PET scanning, were registered at the BC Cancer Agency, and had follow-up information. The median patient age was 52 years. The sensitivity of PET in detecting axillary metastases was 28%, and the specificity was 86%. At diagnosis, 5% of patients were diagnosed with distant metastases. In patients undergoing PET scanning because of suspected recurrence, the sensitivity and specificity for detecting recurrence were 89% and 88%, respectively. Distant metastases were demonstrated in 30% of patients who were thought only to have local-regional recurrence. The results suggest that there are two clinical situations in which PET appears to be particularly valuable. The first is in the evaluation of patients who are suspected of having a tumor recurrence. The other is in identifying patients with multifocal or distant sites of malignancy who otherwise appear to have an isolated, potentially curable, local-regional recurrence.     

Pulmonary aspergillosis: an alternative diagnosis to lung cancer after positive [18F]FDG positron emission tomography

[(18)F]Fluorodexyglucose (FDG) positron emission tomography (PET) scans have significantly improved the diagnosis and staging of lung cancer, but false-positive scans are known to occur due to inflammatory and infectious diseases. Recognition of the conditions leading to false-positive scans is important. Single or multiple pulmonary nodules, with or without cavitation, are classical findings in acute and chronic pulmonary aspergillosis. Clinical features of pulmonary aspergillosis are very similar to those of lung cancer. This report highlights pulmonary aspergillosis as an alternative diagnosis to lung cancer in patients with positive [(18)F]FDG PET scans and the need to strive for presurgical histological diagnosis.     

18-fluorodeoxyglucose positron emission tomography in predicting survival of patients with pancreatic carcinoma

The prediction of survival of patients with pancreatic cancer is usually based on tumor staging and grading and on the level of tumor markers. However, accurate tumor staging can be obtained only after resection, and still there is a great difference in survival rates among patients with the same clinicopathologic parameters. Recently the uptake of 18-fluorodeoxyglucose (FDG) by positron emission tomography (PET) has been found to be correlated with survival in patients with pancreatic cancer. This study evaluated the role of ¹⁸FDG PET as a prognostic factor for patients with pancreatic cancer. From June 1996 to July 2002, a total of 118 patients underwent PET for pancreatic cancer. The standardized uptake value (SUV) of ¹⁸FDG was calculated in 60 of them, and these patients were divided into high (>4) and low (≦4) SUV groups. They were also evaluated according to the tumor node metastasis (TNM) classification system of the International Union Against Cancer, and by tumor grade, medical or surgical treatment, diabetes, age, sex, and CA19-9 serum levels. Twenty-nine cancers showed high and 31 showed low SUVs. Survival was significantly influenced by tumor stage (P = 0.0001), tumor grade (P = 0.01), and SUV (P = 0.005). Multivariate analysis showed that only stage (P = 0.001) and SUV (P = 0.0002)were independent predictors of survival. When patients who were analyzed for SUV were stratified according to the other variables, FDG uptake was related to survival also after stratification for the following: stage III to IVa (P = 0.002), stage IVb (P = 0.01), tumor resection (P = 0.006), moderately differentiated tumors (P = 0.01), age less than 65 years (P = 0.006), CA 19–9 levels greater than 300 kU/L (P = 0.002), and absence of diabetes (P = 0.0001). The SUV calculated with ¹⁸FDG PET is an important prognostic factor for patients with pancreatic cancer and may be useful in selecting patients for therapeutic management. Presented at the Forty-Fourth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Florida, May 17–22, 2003 (oral presentation); and the Sixth National Congress of the Italian Association of Nuclear Medicine, Genoa, Italy, November 15–19, 2002.     

Preliminary experience with 18f-fluoro-deoxy-glucose positron emission tomography/computed tomography in pediatric oncology patients

The aim of this study was to present preliminary experience with FDG PET/CT in pediatric oncology patients in National PET Center, Clinical Center of Serbia and to asses its impact on management of malignancies in children. 33 FDG PET/CT scans were performed on 30 pediatric patients. PET/CT imaging was performed for staging the disease, assessing therapy efficacy and diagnosing recurrent or metastatic disease. FDG PET/CT changed the stage of the disease in 60.6% (20/33) of the cases. 14 patients were down-staged after PET/CT, mostly patients with Hodgkin's disease, were in 7/10 cases PET/CT showed no activity in residual masses. Six scans led to upstage of the disease. In three cases PET/CT did not change the stage of disease, but has showed new distant metastases. In conclusion, FDG PET/CT showed important role in managing pediatric patients with different malignancies and was useful complementary diagnostic tool to conventional imaging methods.     

Diagnostic role of [F-18]-FDG positron emission tomography in restaging renal cell carcinoma

AIMS: To retrospectively assess the diagnostic utility of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in restaging renal cell carcinoma. MATERIALS AND METHODS: We performed whole-body PET scans (45 minutes after intravenous injection of 10 - 15 mCi FDG) for restaging 25 patients (18 male, 7 female, 42 - 81 years old) with known or suspected metastatic renal cell carcinoma. Prior treatments included immunotherapy (n = 1), nephrectomy (n = 16), nephrectomy followed by chemotherapy (n = 3), by radiation therapy (n = 1), and by combined chemoradiation therapy (n = 4). Contrast-enhanced chest, abdomen and pelvis CT studies were available for all patients. Diagnostic validation was by histological sampling (n = 2) and clinical and imaging follow-up for up to 1 year (n = 23). RESULTS: PET was concordant with the findings of CT in 18 patients (3 TN, 15 TP). PET was discordant with CT in 7 patients (28% of total). PET was falsely negative in 6 of these patients and did not demonstrate hypermetabolism in pulmonary (n = 4), mediastinal (n = 2), adrenal (n = 1) and lytic osseous (n = 2) metastatic lesions. PET was falsely positive in the remaining 1 patient in the discordant group with lumbar facet arthropathy. The diagnostic performance of PET in detection of recurrent and metastatic renal cell carcinoma revealed a sensitivity of 71%, specificity of 75%, accuracy of 72%, negative predictive value of 33% and positive predictive value of 94%. CONCLUSIONS: FDG PET demonstrates modest accuracy in the diagnostic imaging evaluation of patients with suspected or known metastatic renal cell carcinoma. A negative study may not exclude disease while a positive study is suspicious for malignancy.     

Value of [18F]-fluorodeoxyglucose (FDG) positron emission tomography in digestive cancerology

COLORECTAL CANCERS: FDG-PET is a very effective tool in the follow-up of colorectal cancer for the early detection of recurrences, the search for other localisations in case of resectable lesions and for the evaluation of therapies. For the other digestive cancers, the data in the literature are less abundant and they do not yet have Marketing Authorization in France. OESOPHAGEAL CANCER: FDG-PET appears very promising for staging and detection of recurrences of oesophageal carcinomas. Pancreatic cancer Although the indication is difficult, FDG-PET appears superior to morphological techniques for the characterization and the locoregional staging of pancreatic tumours. BILARY AND GASTRIC CARCINOMAS: FDG-PET is promising but its role has to be confirmed in larger series for the detection of biliary and gastric carcinomas. OTHER DIGESTIVE TUMOURS: In cases of hepatocarcinoma, FDG-PET appears efficient only in cases of undifferentiated tumours, and in cases of malignant neuroendocrine digestive tumours, is useful in combination with somatostatin receptor imaging.     

18F-fluorodeoxyglucose positron emission tomography influences management decisions in patients with biliary cancer

BACKGROUND: Although (18)F-fluorodeoxyglucose positron emission tomography (PET) has widespread clinical use, its role in cancers of the biliary tract is ill-defined. The aim of this study was to determine if preoperative PET provided additional staging information in patients with biliary tract cancer, beyond that obtained through conventional anatomic imaging. The role of PET in detecting disease recurrence after resection was also examined. STUDY DESIGN: Between March 2001 and October 2003, 126 patients with biopsy-proved or presumed biliary tract cancer (intrahepatic or extrahepatic cholangiocarcinoma and gallbladder carcinoma) underwent PET in addition to standard imaging evaluation. Histologic confirmation of the diagnosis was used as the reference standard with which PET results were compared. Patient followup information and serial imaging were reviewed for progression of lesions detected by PET. RESULTS: Of the 126 study patients, 93 (74%) underwent preoperative staging PET scans, the results of which changed the stage and treatment in 22 patients (24%): 15 of 62 (24%) with cholangiocarcinoma and 7 of 31 (23%) with gallbladder carcinoma. When used to assess for cancer recurrence (n=33), PET identified disease in 86% of patients but altered treatment in only 9%. So, of the entire study group, the findings of PET influenced management in 20% of patients (24% preoperative staging and 9% cancer recurrence). The sensitivity of PET for identifying the primary tumor was 80% overall: 78% for cholangiocarcinoma, 86% for gallbladder carcinoma. CONCLUSIONS: Most biliary tract cancers are (18)F-fluorodeoxyglucose avid tumors. In patients with potentially resectable tumors based on conventional imaging, PET identified occult metastatic disease and changed management in nearly one-fourth of all patients. PET also helped confirm recurrent cancer after resection.     

Value of F-18-fluorodeoxyglucose positron emission tomography after induction therapy of locally advanced bronchogenic carcinoma

OBJECTIVES: Induction therapy is an important treatment option in locally advanced non-small cell lung cancer. F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) has an important role in initial staging. The aim of this study was to assess the value of FDG-PET in restaging after induction therapy and in analyzing tumor viability, nodal status, distant metastases, and prognosis. METHODS: Forty-seven patients with locally advanced non-small cell lung cancer accepted for resection after induction therapy underwent FDG-PET. Images were interpreted visually for mediastinal nodal status and metastatic spread. The FDG accumulation in the tumor site was measured by using the maximum standardized uptake value. RESULTS: Unexpected metastases were detected by means of FDG-PET in 9 patients. Surgical intervention was not performed in 8 patients with confirmed metastases. The rate of unexpected findings increased from complete radiologic remission (0%) over partial remission (9%) to no change (67%). The standardized uptake value was higher in tumors with (n = 26) than in those without (n = 11) histologic proof of viability (6.4 +/- 5.3 vs 2.9 +/- 1.6, P = .006). All patients with standardized uptake values of greater than 5.8 had viable tumors. Sensitivity, specificity, and negative predictive value were 81%, 64%, and 58% for tumor viability and 50%, 88%, and 85% for persistent mediastinal disease. Median survival after resection was greater than 56 months for patients with tumor standardized uptake values of less than 4 and 19 months for patients with standardized uptake values of 4 or greater ( P < .001). CONCLUSION: FDG-PET helps in the selection of patients for resection after induction therapy. It can be used to detect unexpected distant metastases, especially after poor response to induction therapy. Its high negative predictive value in mediastinal restaging allows for omission of repeat mediastinoscopy. Tumor standardized uptake value after induction is a prognostic factor.     

Clinical role of F-18 fluorodeoxyglucose positron emission tomography for detection and management of renal cell carcinoma

PURPOSE: We evaluate the accuracy of F-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) for staging and management of renal cell carcinoma. MATERIALS AND METHODS: FDG-PET was performed in 25 patients with known or suspected primary renal tumors and/or metastatic disease and compared with conventional imaging techniques, including computerized tomography (CT). Histopathological confirmation was obtained in 18 patients and confirmation of the disease was by followup in the remainder. The impact of FDG-PET on disease management was also assessed. RESULTS: Of the 17 patients with known or suspected primary tumors FDG-PET was true positive in 15, true negative in 1 and false-negative in 1. Comparative CT was true positive in 16 patients and false-positive in 1. The accuracy of FDG-PET and CT was similar (94%). All patients would have undergone radical nephrectomy after conventional imaging findings but FDG-PET results altered treatment decisions for 6 (35%), of whom 3 underwent partial nephrectomy and 3 avoided surgery due to confirmation of benign pathology or detection of unsuspected metastatic disease. Of the 8 cases referred for evaluation of local recurrence and/or metastatic disease FDG-PET changed treatment decisions in 4 (50%), with disease up staged in 3 and recurrence excluded in 1. Compared with CT, FDG-PET was able to detect local recurrence and distant metastases more accurately and differentiated recurrence from radiation necrosis. CONCLUSIONS: FDG-PET accurately detected local disease spread and metastatic disease in patients with renal cell carcinoma and altered treatment in 40%. FDG-PET may have a role in the diagnostic evaluation of patients with renal cell carcinoma preoperatively and staging of metastatic disease.     

Mediastinal lymph node staging in suspected lung cancer: comparison of positron emission tomography with F-18-fluorodeoxyglucose and mediastinoscopy

BACKGROUND: In patients with bronchogenic carcinoma, mediastinal lymph node staging is essential for determining treatment options. In this retrospective analysis we compared the results of positron emission tomography (PET) using F-18 fluorodeoxyglucose with those of mediastinoscopy in nodal staging for suspected bronchogenic carcinoma. METHODS: From March 1997 to June 2001, 102 patients (86 male,16 female, age 62 +/- 9 years) underwent both PET and mediastinoscopy for radiologically suspected mediastinal lymph node disease in bronchogenic carcinoma. Total body emission scans were acquired 90 to 150 minutes after injection of 230 MBq of F-18 fluorodeoxyglucose. Mediastinoscopic evaluation of lymph node stations was performed according to the method of Mountain and Dresler (1R, 1L, 2L, 2R, 4L, 4R,7). Patients were eligible if surgical staging was performed within 6 weeks after the PET scan. RESULTS. Of the 102 patients, benign lesions were diagnosed in 15. In 87 patients malignant disease was proven by histology, and bronchogenic carcinoma was found in 82. Of 469 nodal stations analyzed, malignancy was documented by histology in 84. In PET analysis 79 true-positive and 304 true-negative samples were found. Five lymph node stations were false negative, and 81 samples were false positive. False-positive findings in PET frequently were seen in inflammatory lung disease. The sensitivity of PET was 94.1%, specificity was 79% with a diagnostic accuracy of 81.6%. The positive predictive value of PET was 49.3%, and the negative predictive value was 98.4%. CONCLUSIONS: In patients with positive PET scan results histologic verification appears necessary for exact lymph node staging. In view of the negative predictive value mediastinoscopy can be omitted in patients with bronchogenic carcinoma whose PET scan results were negative.     

F-18-fluorodeoxyglucose positron emission tomography in differentiating malignant from benign pancreatic cysts: A prospective study

The differential diagnosis between benign and malignant pancreatic cystic lesions may be very difficult. We recently found that F-18-.uorodeoxyglucose positron emission tomography (18-FDG PET) was useful for the preoperative work-up of pancreatic cystic lesions. This study was undertaken to confirm these results. From February 2000 to July 2003, 50 patients with a pancreatic cystic lesion were prospectively investigated with 18-FDG PET in addition to helical computed tomography (CT) and, in some instances, magnetic resonance imaging (MRI). The validation of diagnosis was based on pathologic findings after surgery (n = 31), percutaneous biopsy (n = 4), and according to follow-up in 15 patients. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value (SUV). The accuracy of FDG PET and CT was determined for preoperative diagnosis of malignant cystic lesions. Seventeen patients had malignant cystic lesions. Sixteen (94%) showed increased 18-FDG uptake (SUV >2.5), including two patients with carcinoma in situ. Eleven patients (65%) were correctly identified as having malignancy by CT. Thirty-three patients had benign tumors: two patients showed increased 18-FDG uptake, and four patients showed CT findings of malignancy. Sensitivity, specificity, positive and negative predictive value, and accuracy of 18-FDG PET and CT in detecting malignant tumors were 94%, 94%, 89%, 97%, and 94% and 65%, 88%, 73%, 83%, and 80%, respectively. 18-FDG PET is accurate in identifying malignant pancreatic cystic lesions and should be used in combination with CT in the preoperative evaluation of patients with pancreatic cystic lesions. A negative result with 18-FDG PET may avoid unnecessary operation in asymptomatic or high-risk patients. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 (oral presentation). This study was supported by the Ministero Università e Ricerca Scientifica (Cofin 2001068593-001), Rome, Italy.     

Prostate cancer localization with 18fluorine fluorocholine positron emission tomography

PURPOSE: We evaluated positron emission tomography (PET) with fluorine fluorocholine (F FCH) for the pretreatment localization of prostate cancer. MATERIALS AND METHODS: A total of 17 patients with prostate cancer who had not yet received treatment for the disease underwent whole body PET following intravenous administration of 3.3 to 4 MBq/kg F FCH. PET findings were compared with the results of prostate sextant biopsy and other imaging studies, and the clinical course. Tracer uptake in prostate sextants was measured as a maximum standardized uptake value (SUVmax) and evaluated as a predictor of the prostate sextant biopsy result by ROC analysis. RESULTS: Prostate sextants positive for malignancy on biopsy demonstrated significantly higher SUVmax than biopsy negative sextants (mean 5.5 vs 3.3, p <0.001). In all 6 cases in which biopsy identified malignancy on only 1 side of the prostate it was possible to identify correctly the affected side based on higher SUVmax. Area under the ROC curve for SUVmax as a discriminator of biopsy positive sextants was 0.86. In 2 patients PET demonstrated areas of abnormal uptake in the retroperitoneum. Computerized tomography confirmed the presence of retroperitoneal lymphadenopathy in these areas. In the 2 patients these lesions regressed following hormonal treatment for prostate cancer. CONCLUSIONS: Malignant tumors in the prostate gland can be localized based on a standardized regional measurement of F FCH uptake. PET with F FCH is potentially useful for staging and localizing prostate cancer.