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Jean-Noël Talbot

Publications and source records attributed to Jean-Noël Talbot.

At least 19 recordsLinked to original sources
PubMed2006

[F-18]-Fluoro-2-deoxy-D: -glucose positron emission tomography as a tool for early detection of immunotherapy response in a murine B cell lymphoma model.

[F-18]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is a non-invasive imaging technique which has recently been validated for the assessment of therapy response in patients with aggressive non-Hodgkin's lymphoma. Our objective was to determine its value for the evaluation of immunotherapy efficacy in immunocompetent Balb/c mice injected with the A20 syngeneic B lymphoma cell line. The high level of in vitro FDG uptake by A20 cells validated the model for further imaging studies. When injected intravenously, the tumour developed as nodular lesions mostly in liver and spleen, thus mimicking the natural course of an aggressive human lymphoma. FDG-PET provided three-dimensional images of tumour extension including non-palpable lesions, in good correlation with ex vivo macroscopic examination. When mice were pre-immunized with an A20 cell lysate in adjuvant before tumour challenge, their significantly longer survival, compared to control mice, were associated with a lower incidence of lymphoma visualized by PET at different time points. Estimation of tumour growth and metabolism using the calculated tumour volumes and maximum standardized uptake values, respectively, also demonstrated delayed lymphoma development and lower activity in the vaccinated mice. Thus, FDG-PET is a sensitive tool relevant for early detection and follow-up of internal tumours, allowing discrimination between treated and non-treated small animal cohorts without invasive intervention.

Animals↗
PubMed2006

PET/CT in patients with hepatocellular carcinoma using [(18)F]fluorocholine: preliminary comparison with [(18)F]FDG PET/CT.

PURPOSE: The diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG) PET is insufficient to characterise hepatocellular carcinoma (HCC) in liver masses and to diagnose all cases of recurrent HCC. HCC has been reported to take up [(11)C]acetate, but routine use of this tracer is difficult. Choline is another tracer of lipid metabolism, present in large amounts in HCC. In a proof-of-concept study, we evaluated [(18)F]fluorocholine (FCH) uptake by HCC and compared FCH PET/CT with FDG PET/CT. METHODS: Twelve patients with newly diagnosed (n=8) or recurrent HCC (n=4) were prospectively enrolled. HCC was assessed by histology in eight cases and by American Association for the Study of Liver Diseases (AASLD) criteria in four cases. All patients underwent whole-body PET/CT 10 min after injection of 4 MBq/kg FCH. Within 1 week, 9 of the 12 patients also underwent whole-body FDG PET/CT 1 h after injection of 5 MBq/kg FDG. RESULTS: The per-patient analysis showed a detection rate of 12/12 using FCH PET/CT for both newly diagnosed and recurrent HCC. The median signal to noise ratio was 1.5+/-0.38. There was a trend towards a higher FCH SUV(max) in well-differentiated HCC (15.6+/-7.9 vs 11.9+/-0.9, NS). Of the nine patients who underwent FCH and FDG PET/CT, all nine were positive with FCH whereas only five were positive with FDG. CONCLUSION: FCH provides a high detection rate for HCC, making it potentially useful in the initial evaluation of HCC or in the detection of recurrent disease. The favourable result of this proof-of-concept study opens the way to a phase III prospective study.

Carcinoma, Hepatocellular↗
PubMed2006

[Basics of PET and PET/CT imaging: instrumentation and radiopharmaceuticals for clinical diagnosis].

Positron emission tomography (PET), like scintigraphy, is a type of functional and molecular imaging. Image resolution is better than with scintigraphy, and tomographic slices are obtained, as with CT and MRI. Modern PET machines are coupled with CT (PET/CT) and yield fused images that combine metabolic and anatomic approaches. Fludeoxyglucose (FDG), a radiolabeled glucose analog, is the most widely used radiopharmaceutical for clinical PET, but several other molecules are proposed for routine use. Clinical trials will determine which are of clinical interest. FDG imaging necessarily involves PET but clinical PET is not only FDG imaging.

Fluorodeoxyglucose F18↗
PubMed2006

[FDG PET and its impact on patient's management in oncology].

FDG, a radioactive glucose analog for PET imaging, requires some precautions: it should be used only in patients with glycemia < 7mmol/L, fasting for at least 6 h but well hydrated, and after pregnancy is ruled out. FDG-PET has many indications in oncology. Its clinical utility has been documented in some circumstances, listed as routine indications in the European Principal Characteristics Summary and the French Standards, Options, and Recommendations. The European "Points to Consider" define as a principal criterion of clinical utility the impact of the imaging results on patient management. The original results presented here evaluate the clinical impact of FDG-PET among patients at Tenon Hospital by the rate of modifications in patient' management, determined with the same questionnaire as that used in two California studies of 2044 patients. Our response rate was lower than in our previous retrospective study in 2000 (34% versus 73%), probably because a prospective evaluation requires more work by the referring physician (who had to respond to two separate letters). On the other hand, the modification rate rose significantly (54% versus 46%, p<0.001), especially for colorectal cancer (58% versus 44%, p<0.02). The California studies had similar response rates (31%-48%, depending on the indication). Their modification rates were also similar, although higher for lymphoma (68%), colorectal (65%) and breast (58%) cancers.

Decision Making↗
PubMed2006

[PET and malignant cerebral tumors].

Normal biodistribution of FDG includes intense physiologic uptake in the brain, which consumes glucose. The high background therefore makes it difficult to detect the foci taking up glucose, which correspond to malignant lesions. FDG PET is nevertheless clinically useful for detecting high-grade gliomas, cerebral lymphomas and, in some cases, unexpected brain metastases in whole-body PET examinations. As an adjunct to CT and MRI, FDG-PET can make stereotactic radiosurgery more precise in targeting primary or secondary brain cancers and can differentiate necrotic fibrosis from viable cancer tissue during follow-up in cases of abnormal or equivocal MRI results. When available, methionine-(11C) PET delineates low grade gliomas accurately. Several fluorine (18F)-labeled radiopharmaceuticals have been proposed in this setting, with FET and FDOPA apparently the most effective. Four original clinical cases illustrating performances of FET and FDOPA PET in this setting are presented.

Brain Neoplasms↗
PubMed2006

[PET in head and neck cancers].

FDG PET is useful when cancer in the head or neck (except for tumors of the salivary glands, which cannot be characterized accurately) is diagnosed or suspected but not confirmed by biopsy. It can, for example, find evidence of suspicious lymph nodes in clinically N0 necks, detect foci suggestive of distant metastases or second cancers, and provide useful prognostic information. Because it can be very difficult to identify anatomical structures and landmarks on PET images in the head and neck region, PET/CT fusion is very helpful in this area. In early assessment of chemotherapy, the absence of a significant reduction in FDG uptake after one or two cycles predicts lack of efficacy and thus indicates the need to modify the regimen. Conversely, the disappearance of FDG foci indicates effective treatment and good prognosis but cannot rule out the persistence of any malignant tissue at the end of treatment, especially neoadjuvant. Diagnostic impact is probably greatest in monitoring for recurrence and restaging known recurrence: FDG PET should be performed - perhaps routinely - early enough that curative options are still open, but long enough after the end of treatment to avoid false positive results from inflammation. The strategy and timing of FDG PET during follow-up should be determined in more detail in the future, as should the role (if any) of fluorotyrosine (FET) PET in squamous cell carcinoma.

Antineoplastic Agents↗
PubMed2006

[FDG-PET in localization of cancers of unknown primary origin].

FDG-PET can be successful in localizing the primary cancer when a metastasis is discovered but no primary tumor can be identified (cancer of unknown primary, or CUP) by physical examination, laboratory testing (for tumor markers, for example) or conventional imaging. The greatest number of PET studies in CUP concern secondary lesions in cervical lymph nodes, and PET is an established clinical use (highest ranking, 1A) according to the 3rd German Consensus Conference and an "option" in the French Standards, Options, and Recommendations. Success rates range from 30% to 50% in most studies using PET; a higher rate was reported recently with PET/CT. FDG-PET should be performed sufficiently early in cases of neurological paraneoplastic syndrome, because established lesions become irreversible. Identification of the antibody present helps to specify the organ and FDG-PET can then localize the lesion; together these techniques make it possible to perform curative surgery even when the primary tumor is not visible. The success rate is somewhat lower than in cases of metastasis, around 35%. The clinical utility of PET in other paraneoplastic syndromes has not yet been sufficiently studied, but these conditions are rare. It is precisely in cases with a kind of 'orphan' indication that FDG PET should be considered, as an effective "problem solver".

Fluorodeoxyglucose F18↗
PubMed2006

[PET in thyroid cancers].

FDG PET can detect thyroid cancer in patients referred for exploration of a different cancer. Because of its lack of specificity, however, this modality is not indicated for examination of thyroid nodules: ultrasonography and fine needle biopsy with cytology allow histological diagnosis, which can be completed by iodine-123 scintigraphy when an autonomous nodule is suspected. No information is currently available about the utility of FDG PET in preoperative staging. In follow-up of patients undergoing thyroidectomy for adenocarcinoma, FDG PET is useful for detecting recurrence in cases where serum thyroglobulin levels rise and iodine-131 scintigraphy is negative: surgical resection may be appropriate. Nonetheless FDG PET should be performed more widely and earlier: the initial presence of foci positive for FDG is a major predictor of shorter survival, and most cancer lesions take up either iodine or FDG. In follow-up of medullary carcinoma, FDG PET detects residual tissue better than any other scintigraphic procedures, especially when serum levels of CEA (carcinoembryonic antigen) are rising rapidly. FDOPA PET seems to have better sensitivity than FDG-PET and may be useful in occult recurrence, as three case reports indicate.

Adenocarcinoma↗
PubMed2006

[PET in primary pulmonary or pleural cancer].

In our hospital as in many others, primary lung cancer is the most frequent indication for FDG PET. Studies have assessed the clinical utility of this imaging modality in characterizing solitary pulmonary nodules or masses, initial staging, defining tumor volume in radiotherapy and searching for recurrence of or restaging non-small cell carcinoma; studies are currently underway to evaluate its use in early assessment of chemotherapy response. Small cell lung cancer has a high FDG uptake and PET/CT can be useful for rapid staging. False negative results may be due to pure bronchioloalveolar carcinomas and endocrine tumors. FDG-PET will certainly play a more important role in the diagnosis and follow-up of pleural cancers in the future. An unexpected positive FDG PET focus should be considered as a warning, but histological proof should precede any irrevocable decisions.

Diagnosis, Differential↗
PubMed2006

Can fluorodihydroxyphenylalanine PET replace somatostatin receptor scintigraphy in patients with digestive endocrine tumors?

UNLABELLED: The aim of this study was to evaluate whether (18)F-fluorodihydroxyphenylalanine ((18)F-FDOPA) PET is accurate for the diagnosis and follow-up of any type of well-differentiated digestive endocrine tumor and to assess its performance compared with standard somatostatin receptor scintigraphy (SRS) using (111)In-pentetreotide. METHODS: We reviewed the results of 33 evaluable (18)F-FDOPA PET and (111)In-pentetreotide SRS examinations performed between March 2002 and September 2005 in 30 patients referred for documented well-differentiated digestive endocrine tumor. RESULTS: The sensitivity and accuracy of (18)F-FDOPA PET were significantly better for carcinoid tumors (defined according to the World Health Organization 2000 classification) (n = 19) than for noncarcinoid tumors (n = 14)-that is, 93% versus 25% for sensitivity (P < 0.01) and 89% versus 36% for accuracy (P < 0.01), respectively. In contrast, the performances of (111)In-pentetreotide SRS did not differ according to the carcinoid or noncarcinoid type of the primary endocrine tumor-that is, 81% versus 75% for sensitivity and 79% versus 71% for accuracy, respectively. In carcinoid tumors, comparison between (18)F-FDOPA PET and (111)In-pentetreotide SRS showed that (18)F-FDOPA PET more accurately evaluated the extent of disease than (111)In-pentetreotide SRS. (111)In-Pentetreotide SRS did not reveal any additional lesions in any case. Conversely, in noncarcinoid tumors, the extent of the disease was more accurately evaluated in all cases by (111)In-pentetreotide SRS than by (18)F-FDOPA PET. CONCLUSION: This preliminary study emphasizes the importance of a precise histologic characterization of well-differentiated digestive endocrine tumor to select the best radiopharmaceutical. (18)F-FDOPA PET appears to be useful in carcinoid tumors and could become the first-line scintigraphic imaging modality for these tumors, but (111)In-pentetreotide SRS appeared to be a better first-line scintigraphic imaging modality for noncarcinoid digestive tumors.

Adult↗
PubMed2005

Impact of CT and 18F-deoxyglucose positron emission tomography image fusion for conformal radiotherapy in esophageal carcinoma.

PURPOSE: To study the impact of fused (18)F-fluoro-deoxy-D-glucose (FDG)-hybrid positron emission tomography (PET) and computed tomography (CT) images on conformal radiotherapy planning for esophageal carcinoma patients. METHODS AND MATERIALS: Thirty-four esophageal carcinoma patients were referred for concomitant radiotherapy and chemotherapy with radical intent. Each patient underwent CT and FDG-hybrid PET for simulation treatment in the same treatment position. PET images were coregistered using five fiducial markers. Target delineation was initially performed on CT images, and the corresponding PET data were subsequently used as an overlay to CT data to define the target volume. RESULTS: (18)F-fluorodeoxy-D-glucose-PET identified previously undetected distant metastatic disease in 2 patients, making them ineligible for curative conformal radiotherapy. The gross tumor volume (GTV) was decreased by CT and FDG image fusion in 12 patients (35%) and increased in 7 patients (21%). The GTV reduction was > or =25% in 4 patients owing to a reduction in the length of the esophageal tumor. The GTV increase was > or =25% with FDG-PET in 2 patients owing to the detection of occult mediastinal lymph node involvement in 1 patient and an increased length of the esophageal tumor in 1 patient. Modifications of the GTV affected the planning treatment volume in 18 patients. Modifications of the delineation of the GTV and displacement of the isocenter of the planning treatment volume by FDG-PET also affected the percentage of total lung volume receiving >20 Gy in 25 patients (74%), with a dose reduction in 12 patients and dose increase in 13. CONCLUSION: In our study, CT and FDG-PET image fusion appeared to have an impact on treatment planning and management of esophageal carcinoma. The affect on treatment outcome remains to be demonstrated.

Adult↗
PubMed2005

Impact of computed tomography and 18F-deoxyglucose coincidence detection emission tomography image fusion for optimization of conformal radiotherapy in non-small-cell lung cancer.

PURPOSE: To report a retrospective study concerning the impact of fused 18F-fluoro-deoxy-D-glucose (FDG)-hybrid positron emission tomography (PET) and CT images on three-dimensional conformal radiotherapy planning for patients with non-small-cell lung cancer. METHODS AND MATERIALS: A total of 101 patients consecutively treated for Stage I-III non-small-cell lung cancer were studied. Each patient underwent CT and FDG-hybrid PET for simulation treatment in the same treatment position. Images were coregistered using five fiducial markers. Target volume delineation was initially performed on the CT images, and the corresponding FDG-PET data were subsequently used as an overlay to the CT data to define the target volume. RESULTS: 18F-fluoro-deoxy-D-glucose-PET identified previously undetected distant metastatic disease in 8 patients, making them ineligible for curative conformal radiotherapy (1 patient presented with some positive uptake corresponding to concomitant pulmonary tuberculosis). Another patient was ineligible for curative treatment because the fused PET-CT images demonstrated excessively extensive intrathoracic disease. The gross tumor volume (GTV) was decreased by CT-PET image fusion in 21 patients (23%) and was increased in 24 patients (26%). The GTV reduction was > or = 25% in 7 patients because CT-PET image fusion reduced the pulmonary GTV in 6 patients (3 patients with atelectasis) and the mediastinal nodal GTV in 1 patient. The GTV increase was > or = 25% in 14 patients owing to an increase in the pulmonary GTV in 11 patients (4 patients with atelectasis) and detection of occult mediastinal lymph node involvement in 3 patients. Of 81 patients receiving a total dose of > or = 60 Gy at the International Commission on Radiation Units and Measurements point, after CT-PET image fusion, the percentage of total lung volume receiving >20 Gy increased in 15 cases and decreased in 22. The percentage of total heart volume receiving >36 Gy increased in 8 patients and decreased in 14. The spinal cord volume receiving at least 45 Gy (2 patients) decreased. Multivariate analysis showed that tumor with atelectasis was the single independent factor that resulted in a significant effect on the modification of the size of the GTV by FDG-PET: tumor with atelectasis (with vs. without atelectasis, p = 0.0001). CONCLUSION: The results of our study have confirmed that integrated hybrid PET/CT in the treatment position and coregistered images have an impact on treatment planning and management of non-small-cell lung cancer. However, FDG images using dedicated PET scanners and respiration-gated acquisition protocols could improve the PET-CT image coregistration. Furthermore, the impact on treatment outcome remains to be demonstrated.

Adult↗
PubMed2005

Usefulness of combination of high-resolution ultrasonography and dual-phase dual-isotope iodine 123/technetium Tc 99m sestamibi scintigraphy for the preoperative localization of hyperplastic parathyroid glands in renal hyperparathyroidism.

BACKGROUND: The usefulness of both dual-phase dual-isotope iodine 123 ( 123 I)/technetium Tc 99m ( 99m Tc) sestamibi scintigraphy and ultrasonography for the detection of hyperplastic parathyroid glands secondary to renal hyperparathyroidism is rarely addressed; most studies focus on primary hyperparathyroidism. However, it may be crucial to identify and accurately localize hyperplastic glands before surgery. METHODS: To study the usefulness of high-resolution ultrasonography (performed by both the radiologist and surgeon) and dual-phase dual-isotope 123 I/ 99m Tc sestamibi scintigraphy in patients with renal hyperparathyroidism, a series of 20 patients consecutively referred for parathyroidectomy was studied prospectively. Results of both examinations, independently scored, were correlated with surgical and histopathologic findings for each hyperplastic parathyroid gland localization. RESULTS: All parathyroid glands except 1 were found during primary surgery consisting of a subtotal parathyroidectomy (success rate, 99%). The missed gland was removed successfully 1 month later. Neither supernumerary nor ectopic glands were found. Mean weight of totally removed parathyroid glands was 633 mg. Ultrasonography detected 75% of hyperplastic parathyroid glands; dual-phase 123 I/ 99m Tc sestamibi scintigraphy, 66%; and a combination of both, 88%. Most missed glands at scintigraphy corresponded to superior glands, whereas false-negative results at ultrasonography correlated with low gland weight. CONCLUSION: Combined ultrasonography and 123 I/ 99m Tc sestamibi scintigraphy should be considered for routine use to localize hyperplastic parathyroid glands in patients with renal hyperparathyroidism undergoing surgery. We suggest performing scintigraphy first, before ultrasonography, to guide the radiologist to areas of hyperfunctioning glands. In our experience, this proved very helpful in achieving a high surgical success rate in patients with renal hyperparathyroidism, especially when the surgeon visualizes the parathyroid glands at ultrasonography.

Adult↗
PubMed2005

Persistent foreign body reaction around inguinal mesh prostheses: a potential pitfall of FDG PET.

OBJECTIVE: FDG PET has been recognized as an efficient imaging technique for the treatment of oncology patients. However, false-positive results can occur. The purpose of this study is to describe three oncology patients with persistent FDG up-take around inguinal mesh prostheses that occurred up to 10 years after the surgical repair of inguinal hernias and led to false-positive results. CONCLUSION: Remote mesh prostheses can induce FDG uptake because of persistent foreign body reaction. Consequently, each time an unexpected pelvic focus is noticed on FDG PET, the medical history of patients should be carefully reviewed to avoid false-positive results.

Aged↗
PubMed2005

[Understanding positon emission tomography (PET) with [18F]-FDG in clinical oncology. Informations dedicated to patients and relatives].

In response to the evolution of the information-seeking behaviour of patients and concerns from health professionals regarding cancer patient information, the French National Federation of Comprehensive Cancer Centres (FNCLCC) introduced, in 1998, an information and education program dedicated to patients and relatives, the SOR SAVOIR PATIENT program (SSP). The methodology of this program adheres to established quality criteria regarding the elaboration of patient information. Cancer patient information, developed in this program, is based on clinical practice guidelines produced by the FNCLCC and the twenty French regional cancer centres, the National League against Cancer, the French Hospital Federation, the National Oncology Federation of Regional and University Hospitals, the French Oncology Federation of General Hospitals, many learned societies, as well as an active participation of patients, former patients and caregivers. The guidelines, "Standards, Options: Recommendations" (SOR) are used as primary information sources. The handbook SOR SAVOIR PATIENT Understanding positron emission tomography (PET) with [18F]-FDG in clinical oncology, integrally published in this issue of the Bulletin du Cancer, is an adapted version of the clinical practice guidelines (CPG) Standards, Options and Recommendations for positron emission tomography (PET) with [18F]-FDG in clinical oncology. The main objectives of this article are to allow persons affected by cancer and their close relatives to better understand this medical imaging technique and its implementation. This document also offers health professionals a synthetic evidence-based patient information source that should help them communicate that information during the physician-patient encounter. Positron emission tomography (PET) is a scintigraphy technique using a radiotracer, [18F]-fluorodeoxyglucose (abbreviated [18F]-FDG), administered intravenously into the patient's arm. This tracer, similar to glucose (sugar), binds to cancer cells and temporarily emits radiations that can be recorded by a special camera in the PET scanner. PET scanning can be used to obtain complementary information at different stages of the disease, whether for assessing diagnosis, treatment evolution or follow-up. By 2007, in the framework of the government plan against cancer, about seventy-five PET scanners are expected to be installed in France. Twenty-four are currently in use; a similar number is under installation. At the end of this process, all French regions should have at least one PET imaging equipment. The SOR SAVOIR PATIENT guide: Understanding positron emission tomography (PET) with [18F]-FDG in clinical oncology and the integral report of CPG SOR 2003: Standards, Options and Recommendations for positron emission tomography (PET) with [18F]-FDG in clinical oncology can be downloaded from the FNCLCC website: http:\\www.fnclcc.fr.

Decision Making↗