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Norbert Avril

Publications and source records attributed to Norbert Avril.

18 recordsLinked to original sources
PubMed2007

Clinical use of combined positron emission tomography and computed tomography (FDG-PET/CT) in recurrent ovarian cancer.

OBJECTIVE: The aim of this study was to evaluate the use of co-registered PET/CT using F-18 fluorodeoxyglucose (FDG) for surveillance and follow-up of ovarian cancer patients to detect recurrent disease. MATERIAL AND METHODS: A retrospective chart review was performed on 39 ovarian cancer patients who underwent a total of 59 FDG-PET/CT scans. The following information was obtained: clinical indication for FDG-PET/CT, the results of FDG-PET/CT particularly with regard to the additional diagnostic information, the localization of disease and subsequent clinical patient management. RESULTS: Twenty-four FDG-PET/CT were performed in 22 patients with previously negative or indeterminate CT scans but rising CA-125 levels providing a sensitivity of 90% for localizing disease. Nine FDG-PET/CT in 8 patients with clinical symptoms of recurrence but normal CA-125 levels detected all three patients who had recurrent disease confirmed within 6 months of follow-up. In addition, 4 FDG-PET/CT performed as routine follow-up with no clinical evidence of recurrent disease were true-negative in all cases. Fourteen FDG-PET/CT in 12 patients with recurrent disease already identified by conventional CT imaging were useful in guiding treatment decisions such as radiation therapy, surgery or chemotherapy by confirming the recurrence and more precisely localizing the site(s) of disease. Of note, FDG-PET/CT helped to avoid surgery in four patients who had additional disease detected in unresectable anatomic areas. A total of 51 FDG-PET/CT were performed in the patients described above with an overall sensitivity and specificity of 94.5% and 100%, respectively. Eight FDG-PET/CT scans in five patients performed for assessment of treatment response following chemotherapy or radiation were useful as the disease was not clearly visualized by conventional CT imaging at baseline. CONCLUSIONS: In our experience, FDG-PET/CT has the greatest utility in settings of suspected ovarian cancer recurrence, particularly in patients with rising CA-125 levels and negative conventional imaging. FDG-PET/CT was specifically helpful in optimizing the selection of patients for site-specific treatment, including radiation treatment planning, and aided in the selection of optimal surgical candidates. The co-registered metabolic-anatomic information from combined FDG-PET/CT holds promise in replacing the single imaging procedures.

Adult↗
PubMed2006

Posttreatment assessment of response using FDG-PET/CT for patients treated with definitive radiation therapy for head and neck cancers.

PURPOSE: The goal of this study was to evaluate coregistered [18F] fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) for the detection of persistent disease after definitive radiation therapy in head and neck cancer. METHODS AND MATERIALS: Posttreatment FDG-PET/CT was performed in 28 patients on average 8 weeks (range, 4 to 15.7 weeks) after completing definitive radiation therapy. FDG-PET/CT was visually analyzed for the entire patient group and at two time points (4-8 and >8 weeks) after treatment. The contrast-enhanced CT portion of PET/CT was separately analyzed blinded to the results of coregistered FDG-PET/CT and classified as negative or positive for residual locoregional disease. Pathologic findings and clinical follow-up served as the reference standard. RESULTS: Follow-up data were available for all 28 patients (median, 17.6 months). Regarding the detection of residual disease, the overall sensitivity and specificity of FDG-PET/CT was 76.9% and 93.3%, respectively, compared with 92.3% and 46.7% for contrast-enhanced CT. The accuracy of FDG-PET/CT was 85.7%, compared with 67.9% for CT alone. All false-negative (n = 3) and false-positive (n = 1) FDG-PET/CT results occurred between 4 and 8 weeks after treatment. At 8 weeks or later after treatment, the specificity of CT was 28%, compared with 100% for FDG-PET/CT. CONCLUSIONS: The metabolic-anatomic information from coregistered FDG-PET/CT provided the most accurate assessment for treatment response when performed later than 8 weeks after the conclusion of radiation therapy. FDG-PET/CT excelled by a higher specificity and overall diagnostic performance than CT imaging alone. These results support a potential clinical role of FDG-PET/CT in the early assessment of therapy response after definitive radiation therapy.

Adult↗
PubMed2005

Full-dose 90Y ibritumomab tiuxetan therapy is safe in patients with prior myeloablative chemotherapy.

PURPOSE: Targeted radioimmunotherapy with yttrium-90 (90Y)-labeled ibritumomab tiuxetan (Zevalin, IDEC-Biogen, San Diego, CA) has shown significant activity in the treatment of relapsed or refractory CD20+ non-Hodgkin's lymphoma. Eligibility criteria used in phase I trials, and adopted in phase II and III trials, excluded patients with prior myeloablative therapy. We treated eight patients with 90Y ibritumomab tiuxetan who had prior autologous stem cell transplant, but met all other treatment criteria. EXPERIMENTAL DESIGN: Eight patients with CD20+ non-Hodgkin's lymphoma had extensive prior therapy including myeloablative chemotherapy but did not receive total body irradiation. Each had bone marrow cellularity of >15%, platelet count of >100,000/mm3, and one had documented lymphomatous bone marrow involvement of <25%. The standard course of 0.3 to 0.4 mCi/kg of 90Y ibritumomab tiuxetan was administered to patients at full dose. 18-Flouro-deoxyglucose positron emission tomography/computed tomography scans were done at pretreatment and approximately 12 weeks after treatment to assess patient response. Maximum toxicities were monitored and classified according to the Common Terminology Criteria for Adverse Events (ver. 3.0). RESULTS: Toxicities observed included grade 4 thrombocytopenia in three of eight evaluable patients and grade 4 neutropenia in one of eight evaluable patients. One patient had a neutropenic fever; all patients were off blood product support 12 weeks post-zevalin. Complete response by 18-flouro-deoxyglucose positron emission tomography/computed tomography imaging occurred in one of seven evaluable patients and one patient treated as consolidation had no evidence of disease. CONCLUSION: Our experience suggests that 90Y ibritumomab tiuxetan treatment is safe for use in patients with prior myeloablative therapy when the general inclusion criteria are fulfilled. In this small series, the response rates, however, are limited. Nevertheless, 90Y ibritumomab tiuxetan treatment may provide clinical benefit in carefully selected extensively pretreated patients.

Adult↗
PubMed2005

Prediction of response to neoadjuvant chemotherapy by sequential F-18-fluorodeoxyglucose positron emission tomography in patients with advanced-stage ovarian cancer.

PURPOSE: The aim of this study was to evaluate sequential F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) to predict patient outcome after the first and third cycle of neoadjuvant chemotherapy in advanced-stage (International Federation of Gynecology and Obstetrics stages IIIC and IV) ovarian cancer. PATIENTS AND METHODS: Thirty-three patients received three cycles of carboplatin-based chemotherapy, followed by cytoreductive surgery. Quantitative FDG-PET of the abdomen and pelvis was acquired before treatment and after the first and third cycle of chemotherapy. Changes in tumoral FDG uptake, expressed as standardized uptake values (SUV), were compared with clinical and histopathologic response; overall survival served as a reference. RESULTS: A significant correlation was observed between FDG-PET metabolic response after the first (P = .008) and third (P = .005) cycle of chemotherapy and overall survival. By using a threshold for decrease in SUV from baseline of 20% after the first cycle, median overall survival was 38.3 months in metabolic responders compared with 23.1 months in metabolic nonresponders. At a threshold of 55% decrease in SUV after the third cycle median overall survival was 38.9 months in metabolic responders compared with 19.7 months in nonresponders. There was no correlation between clinical response criteria (P = .7) or CA125 response criteria (P = .5) and overall survival. There was only a weak correlation (P = .09) between histopathologic response criteria and overall survival. CONCLUSION: Sequential FDG-PET predicted patient outcome as early as after the first cycle of neoadjuvant chemotherapy and was more accurate than clinical or histopathologic response criteria including changes in tumor marker CA125. FDG-PET appears to be a promising tool for early prediction of response to chemotherapy.

Adult↗
PubMed2005

Radioimmunotherapy using 131I-rituximab in patients with advanced stage B-cell non-Hodgkin's lymphoma: initial experience.

PURPOSE: The aim of this study was to evaluate the safety, toxicity and therapeutic response of non-myeloablative radioimmunotherapy using 131I-rituximab in previously heavily treated patients with B-cell non-Hodgkin's lymphoma (B-NHL). METHODS: Nine patients with relapsed, refractory or transformed B-NHL received ten radioimmunotherapies. Patients had a median of 5 (range 2-7) prior standard therapies. Four patients had received prior high-dose chemotherapy followed by autologous stem cell transplantation, and eight had received prior rituximab therapy. Histopathology consisted of four mantle cell, one follicular and four diffuse large B-cell lymphomas. Rituximab, a monoclonal chimeric anti-CD20 antibody (IDEC-C2B8), was labelled with 131I using the Iodogen method. The administered activity (2,200+/-600 MBq) was based on a dosimetrically calculated 45 cGy total-body radiation dose. All patients received an infusion of 2.5 mg/kg of rituximab prior to administration of the radiopharmaceutical. RESULTS: No acute adverse effects were observed after the administration of 131I-rituximab. Radioimmunotherapy was safe in our patient group and achieved one complete response ongoing at 14 months and two partial responses progressing at 12 and 13 months after treatment. One partial responder was re-treated with radioimmunotherapy and achieved an additional progression-free interval of 7 months. Four non-responders with bulky disease died 4.8+/-2.0 months after therapy. Three patients had an elevated serum lactate dehydrogenase (LDH) level prior to radioimmunotherapy and none of the patients responded. Of two patients who received radioimmunotherapy as an additional treatment after salvage chemotherapy, one continues to be disease-free at 9 months and one relapsed at 5 months' follow-up. Reversible grade 3 or 4 haematological toxicity occurred in seven of nine patients. Median nadirs were 35 days for platelets, 44 days for leucocytes and 57 days for erythrocytes. CONCLUSION: Radioimmunotherapy with 131I-rituximab in previously heavily treated B-NHL patients was safe and well tolerated, and four out of ten therapies induced responses. Radioimmunotherapy was less efficient in patients with bulky disease and elevated LDH. Severe haematological toxicity in seven patients did not cause significant clinical problems. Radioimmunotherapy seems to be an additional therapeutic option in carefully selected therapy-refractory B-NHL patients.

Adult↗
PubMed2005

90Y microsphere treatment of unresectable liver metastases: changes in 18F-FDG uptake and tumour size on PET/CT.

PURPOSE: The intra-arterial administration of 90Y microspheres is a new palliative treatment option for unresectable liver metastases. The aim of this study was to quantitatively assess changes in FDG uptake and tumour size following 90Y microsphere treatment (SIR-Spheres) using 18F-fluorodeoxyglucose (FDG) PET/CT imaging. METHODS: Five patients with unresectable liver metastases who had failed multiple prior chemotherapy regimens received seven 90Y microsphere treatments to a single liver lobe. All patients underwent a baseline PET/CT scan prior to treatment, as well as up to four follow-up PET/CT scans. The tumour area of 30 liver metastases was measured on CT and the FDG uptake was semiquantitatively assessed by calculation of standardised uptake values (SUVs). A total of 18 FDG-PET/CT scans were performed. RESULTS: The SUVs in the 30 treated liver metastases decreased from 6.5+/-2.3 at baseline to 4.2+/-1.8 after the first follow-up PET/CT scan (p=0.001). In contrast, the SUVs of untreated metastases increased slightly from 7.2+/-2.3 to 8.0+/-0.8. There was no difference in FDG uptake in treated versus untreated normal liver tissue. Using a previously defined threshold of 20% decrease in SUV from baseline to determine response, 20 out of 30 liver metastases were considered to have responded at the first follow-up PET/CT scan approximately 1 month after treatment. In these metastases, the SUV decreased by 47+/-12%, compared with a slight increase by 5.9+/-19% in ten non-responding metastases (p=0.0001). The changes in tumour size did not correlate with changes in FDG uptake. On the first follow-up PET/CT scan, the tumour area on CT increased by 3.1+/-57% in treated metastases compared with 23.3+/-32% in untreated metastases. A wide range of post-treatment changes of target lesions was observed on CT, including an increase in the size of hypodense lesions, necrotic features and complete resolution of CT abnormalities. CONCLUSION: The metabolic information obtained from FDG-PET/CT seems to provide a more accurate and earlier assessment of therapy response following 90Y microsphere treatment than does the anatomical CT information.

Adult↗
PubMed2005

Whole-body PET/CT: spectrum of physiological variants, artifacts and interpretative pitfalls in cancer patients.

Accurate diagnosis and staging in oncology is essential in the evaluation of cancer for optimal patient outcome. Conventional imaging techniques, such as computed tomography (CT), rely basically on morphological changes for tumour detection. Clinical experience, however, shows that morphological criteria may be misleading and may not always allow differentiation between benign and malignant lesions. Positron emission tomography (PET) with [F]fluorodeoxyglucose (FDG) is rapidly gaining a critical role in the clinical evaluation of patients with cancer. However, PET lacks anatomical landmarks for topographic orientation, and identification of abnormal glucose metabolic activity in regions close to organs with variable physiological FDG uptake can be difficult. To overcome these difficulties, a combined PET/CT scanner that acquires both functional (PET) and CT images has been recently developed. Proper interpretation of PET (and PET/CT) images requires a thorough understanding of the normal physiological distribution of FDG in the body, along with a knowledge of frequently encountered physiological variations in FDG distribution, and recognition of non-malignant causes of FDG uptake that can be confused with a malignant neoplasm. In addition, because of the utilization of the CT transmission information for the correction of the attenuation of the PET emission data (and for the reconstruction of the PET images), some artifacts may be generated. As a consequence, CT based attenuation correction of PET images may result in erroneous PET/CT interpretations. The aim of this extensively illustrated paper is to demonstrate several potential pitfalls encountered during the interpretation of PET/CT images so that radiologists can avoid false positive diagnoses and recognize inherently non-specific findings on PET/CT images obtained for oncological diagnosis.

Artifacts↗
PubMed2005

FDG PET CT assessment of treatment response after yttrium-90 ibritumomab tiuxetan radioimmunotherapy.

Yttrium-90 ibritumomab tiuxetan (Zevalin; IDEC Pharmaceuticals Corp., San Diego, CA) is the first radioimmunotherapy agent approved by the U.S. Food and Drug Administration (FDA) for treatment of non-Hodgkin lymphoma. In a randomized clinical trial comparing Zevalin with rituximab, the overall response rate was 80% and 56%, respectively. Response was determined by assessing the size of lymph nodes on CT scans. FDG PET has been well accepted as an accurate imaging study for staging non-Hodgkin lymphoma and evaluating response to treatment. Simultaneous FDG PET and CT imaging (PET CT) provides coregistered functional PET images with anatomic CT images. We describe 2 cases of non-Hodgkin lymphoma treated in which response was followed using PET CT.

Antibodies, Monoclonal↗
PubMed2005

Early prediction of response to chemotherapy in metastatic breast cancer using sequential 18F-FDG PET.

UNLABELLED: Chemotherapy is currently the treatment of choice for patients with high-risk metastatic breast cancer. Clinical response is determined after several cycles of chemotherapy by changes in tumor size as assessed by conventional imaging procedures including CT, MRI, plain film radiography, or ultrasound. The aim of this study was to evaluate the use of sequential 18F-FDG PET to predict response after the first and second cycles of standardized chemotherapy for metastatic breast cancer. METHODS: Eleven patients with 26 metastatic lesions underwent 31 (18)F-FDG PET examinations (240-400 MBq of 18F-FDG; 10-min 2-dimensional emission and transmission scans). Clinical response, as assessed by conventional imaging after completion of chemotherapy, served as the reference. 18F-FDG PET images after the first and second cycles of chemotherapy were analyzed semiquantitatively for each metastatic lesion using standardized uptake values (SUVs) normalized to patients' blood glucose levels. In addition, whole-body 18F-FDG PET images were viewed for overall changes in the 18F-FDG uptake pattern of metastatic lesions within individual patients and compared with conventional imaging results after the third and sixth cycles of chemotherapy. RESULTS: After completion of chemotherapy, 17 metastatic lesions responded, as assessed by conventional imaging procedures. In those lesions, SUV decreased to 72% +/- 21% after the first cycle and 54% +/- 16% after the second cycle, when compared with the baseline PET scan. In contrast, 18F-FDG uptake in lesions not responding to chemotherapy (n = 9) declined only to 94% +/- 19% after the first cycle and 79% +/- 9% after the second cycle. The differences between responding and nonresponding lesions were statistically significant after the first (P = 0.02) and second (P = 0.003) cycles. Visual analysis of 18F-FDG PET images correctly predicted the response in all patients as early as after the first cycle of chemotherapy. As assessed by 18F-FDG PET, the overall survival in nonresponders (n = 5) was 8.8 mo, compared with 19.2 mo in responders (n = 6). CONCLUSION: In patients with metastatic breast cancer, sequential 18F-FDG PET allowed prediction of response to treatment after the first cycle of chemotherapy. The use of 18F-FDG PET as a surrogate endpoint for monitoring therapy response offers improved patient care by individualizing treatment and avoiding ineffective chemotherapy.

Adult↗
PubMed2004

Hybrid PET-CT simulation for radiation treatment planning in head-and-neck cancers: a brief technical report.

PURPOSE: To prospectively study the impact on tumor and normal tissue delineation for RT planning by use of hybrid PET-CT simulation for patients with head-and-neck cancer. METHODS AND MATERIALS: Twenty-one patients were simulated in treatment position on a hybrid PET-CT scanner. Images were transferred to the Varian Eclipse planning system. Abnormal areas of fluorodeoxyglucose (FDG) uptake were contoured on PET for the gross tumor volume of primaries (GTVp) and abnormal nodal region of primaries (ABNp) then compared with the same CT gross tumor volumes (GTVc) and abnormal nodal region (ABNc). A statistical analysis was performed to evaluate the correlation of PET and CT volumes. RESULTS: Positron emission tomography demonstrated the primary in all cases, whereas CT did not find the primary in 3 cases. In 8 patients, additional areas of disease were seen only in PET. The average ratio of GTVc/GTVp was 3.1 (range, 0.3-23.6), whereas for ABNc/ABNp was 0.7 (range, 0-4). Volumes for the primaries were significantly larger on CT than on PET (p = 0.002) but not for nodal regions (p = 0.5). CONCLUSIONS: Hybrid PET-CT simulation is feasible and provides valuable information that results in greater delineation of normal tissues from tumor bearing areas at high risk for recurrence. This finding may further improve therapeutic window for IMRT for head-and-neck cancers.

Adult↗
PubMed2004

Single-detector helical CT in PET-CT: assessment of image quality.

OBJECTIVE: CT in positron emission tomography (PET)-CT imaging is often performed as a single scan from the base of the skull to the groin, potentially resulting in degradation of the quality of CT scans depending on the position of the patient's arms and mode of breathing and the use and timing of IV contrast injection. The aim of our study was to assess the impact of artifacts on the diagnostic quality of CT scans using a single-detector helical CT scanner in PET-CT imaging. MATERIALS AND METHODS: Two radiologists retrospectively evaluated the diagnostic image quality of CT scans obtained with PET-CT in 81 patients with lymphoma. The severity of the artifacts related to the position of the patient's arms beside the body, the influence of breathing motion, and the presence of contrast material in the upper thoracic veins were ranked using a 4-point scale. RESULTS: Performing CT with the patient's arms positioned beside the body resulted in streak artifacts, predominantly in the upper abdomen, that were graded as mild in 22%, moderate in 40%, and severe in 38% of the scans. A patient's weight significantly correlated with the degree of severity of the artifacts (p < 0.05). Shallow breathing by the patient during scanning caused blurring and double-imaging, again predominantly in the upper abdomen, that were graded as mild in 23%, moderate in 49%, or severe in 28% of the scans. In 84% of the CT scans obtained with IV contrast material, the image quality of the upper thoracic region was moderately (27%) or severely (57%) degraded by streak artifacts from highly concentrated contrast material in the upper thoracic veins. CONCLUSION: The use of a single-detector CT scanner in whole-body PET-CT decreases the image quality of CT scans because of streak artifacts that occur predominantly in scans of the upper abdomen. Scanning with the patient's arms raised eliminates the streak artifacts in scans of the abdominal region. With the new generation of PET-CT devices equipped with MDCT scanners, breathing motion artifacts can be expected to be eliminated if protocols for breath-hold CT are applied. Reversing the direction of CT scanning allows one to avoid imaging the thoracic region at a time when undiluted IV contrast material is still present in the upper thoracic veins.

Adolescent↗
PubMed2003

Defining the success of cardiac gene therapy: how can nuclear imaging contribute?

Gene therapy is a promising modality for the treatment of various cardiovascular diseases such as ischaemia, heart failure, restenosis after revascularisation, hypertension and hyperlipidaemia. An increasing number of approaches are moving from experimental and preclinical validation to clinical application, and several multi-centre trials are currently underway. Despite the rapid progress in cardiac gene therapy, many basic tools and principles remain under development. Questions with regard to the optimal method for gene delivery in a given situation remain open, as do questions concerning therapeutic efficacy and the time course and magnitude of gene expression in target and remote areas. Nuclear imaging provides valuable tools to address these open issues non-invasively. Functional effects of molecular therapy at the tissue level can be identified using tracers of blood flow, metabolism, innervation or cell death. The use of reporter genes and radiolabelled reporter probes allows for non-invasive assessment of location, magnitude and persistence of transgene expression in the heart and the whole body. Co-expression of a reporter gene will allow for indirect imaging of the expression of a therapeutic gene of choice, and linkage of measures of transgene expression to downstream functional effects will enhance the understanding of basic mechanisms of cardiac gene therapy. Hence, nuclear imaging offers great potential to facilitate and refine the determination of therapeutic effects in preclinical and clinical cardiovascular gene therapy.

Arteriosclerosis↗
PubMed1999

Utility of PET in Breast Cancer.

Breast cancer represents the most frequent malignant disease in women and the second leading cause of cancer death in western countries. Current available treatment includes surgery, radiation therapy, chemotherapy, and hormonal therapy. The disease is often curable when detected in early stages. Mammography is the most important screening modality; however, limitations of available procedures for the diagnosis and accurate staging of breast cancer has increased the application of metabolic imaging by positron emission tomography (PET). PET using the radiolabeled glucose analogue, F-18 fluorodeoxyglucose (FDG), enables visualization of increased glucose metabolism of malignant tissue. PET has been used successfully in an increasing number of oncological applications. It is an excellent clinical method to detect breast cancer over 1 cm in diameter and to accurately identify the extent of axillary lymph node metastases in patients with locally advanced disease. Recent reports have shown the high accuracy of FDG-PET imaging for staging of breast cancer patient by using whole-body PET imaging. The metabolic signal of tumor tissue allows for monitoring the effect of chemotherapy. FDG-PET can differentiate between responder and nonresponder early in the course of therapy. By identifying nonresponding patients, PET can help to avoid ineffective therapy and therefore, reduce toxic side effects in these patients.

Journal Article↗
PubMedDate not supplied

Intraoperative examination of sentinel lymph nodes by ultrarapid immunohistochemistry.

The recently developed method of ultrarapid immunohistochemistry (IHC) was applied to the intraoperative examination of sentinel lymph nodes (SLNs) in breast cancer patients. In a prospective study of 50 patients with invasive breast carcinomas, a total of 60 SLNs were studied. Among them, 33 SLNs from 30 patients were studied intraoperatively using a direct immunoperoxidase method with anticytokeratin antibody clone MNF116. This technique has a turnaround time of less than 20 minutes. Ultrarapid IHC revealed 15 positive SLNs compared to 14 positive SLNs using hematoxylin and eosin (H and E) frozen sections. The one SLN missed in H and E frozen sections presented with cytokeratin-positive isolated tumor cells in the lymph node sinus. After paraffin embedding, H and E-stained serial step sections of the SLN specimens detected another two patients with isolated tumor cells. We also examined the remaining axillary lymph nodes (ALNs) by H and E-stained serial step paraffin sections. From 17 of the 30 patients with positive SLNs, 6 patients also had metastatic involvement of the ALNs of level I or II. Thus ultrarapid IHC was a very sensitive and rapid technique for the intraoperative detection of metastatic involvement of SLNs in breast cancer patients. This technique may be a useful complementary tool for the intraoperative study of SLNs, particularly in tumors that are a diagnostic challenge, such as lobular carcinoma.

Adult↗