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P Rigo

Publications and source records attributed to P Rigo.

At least 19 recordsLinked to original sources
PubMed2003

Early detection of relapse by whole-body positron emission tomography in the follow-up of patients with Hodgkin's disease.

BACKGROUND: Relapse after treatment of Hodgkin's disease (HD) is usually identified as a result of the investigation of symptoms. We undertook this study to examine the value of whole-body positron emission tomography (PET) for the detection of preclinical relapse. PATIENTS AND METHODS: Thirty-six patients underwent 2-[fluorine-18]fluoro-2-deoxy-D-glucose ((18)F-FDG) PET at the end of treatment and than every 4-6 months for 2-3 years after the end of polychemotherapy and/or radiotherapy. In those cases of abnormal (18)F-FDG accumulation a confirmatory study was performed 4-6 weeks later. RESULTS: One patient had residual tumor and four patients relapsed during a follow-up of 5-24 months. All five events were correctly identified early by (18)F-FDG PET. Residual tumor or relapse was never first diagnosed based on clinical examination, laboratory findings or computed tomography (CT) studies. Two patients presented B symptoms and the three others were asymptomatic at the time of residual disease or relapse. Confirmation of residual disease or relapse was obtained by biopsy in four patients 1, 1, 5 and 9 months after PET and by unequivocal clinical symptoms and CT studies in one patient 3 months after PET. False-positive (18)F-FDG PET studies incorrectly suggested possible relapse in six other patients, but the confirmatory PET was always negative. Our study also provides important information about physiological (18)F-FDG uptake in the thymus. CONCLUSIONS: Our data suggest the potential of (18)F-FDG PET to detect preclinical relapse in patients with HD. This could help identify patients requiring salvage chemotherapy at the time of minimal disease rather than at the time of clinically overt relapse. Further studies are warranted to determine the impact of PET on treatment management and outcome. In fact, the aim of follow-up procedures is not only to detect preclinical relapse but mainly to obtain better results by starting salvage treatment earlier. A cost-benefit analysis will also be necessary before (18)F-FDG PET can be used routinely in the follow-up of patients with HD.

Adolescent↗
PubMed2003

Whole-body positron emission tomography using fluorodeoxyglucose in patients with metastases of unknown primary tumours (CUP syndrome).

The aim of this study was to evaluate the clinical performances of whole body 2-[18F]fluorodeoxyglucose positron emission tomography (FDG PET) imaging for the detection of the primary tumour in patients with metastases of unknown origin. Forty-one patients, without previous history of known cancer (18 women and 23 men; average age 64.1 years) with metastasis confirmed by histopathological analysis were included in a retrospective study. Results of PET were compared with those of techniques used in the current conventional diagnostic procedure. All known metastatic lesions were detected by PET. There were 26 true-positive and two false-negative results. Primary tumour remained undetermined in eight patients after conventional investigations and PET. PET was superior to conventional diagnostic procedure in 11 patients and led to modify treatment in 11 patients. Sensitivity of PET was superior than computed tomography in detecting abdominal primary tumours. FDG PET is useful in patients with unknown primary tumour because its sensitivity is good and it could modify the disease management. Otherwise, PET allows the evaluation of the extent of the disease and could be used to monitor treatment efficiency. Its contribution has to be evaluated particularly in patients with primary tumour with a specific treatment.

Adult↗
PubMed2002

[Horton's disease and extra-temporal vessel locations: role of 18FDG PET scan. Report of 3 cases and review of the literature].

PURPOSE: We report three cases of Horton's disease, in which F18-Fluorine-2-Deoxy-D-Glucose (18FDG) positron emission tomography (PET) demonstrated a clinically unsuspected extra-cranial vessels hypermetabolism. METHODS: Fully corrected whole-body PET was performed in three patients (two women, one man) for exploring a marked inflammatory syndrome. Scanning was acquired 60 min after i.v. injection of 222 MBq of 18FDG in average. RESULTS: In two patients with histologically proven Horton's disease, PET alone showed increased glucose metabolism involving the carotid and sub-clavian arteries as well as the ascending aorta, aortic arch, thoracic and abdominal aorta, and the iliac and femoral arteries. In the third patient, by detecting cervical, thoracic and abdominal vessel hypermetabolism, PET non-invasively contributed to the diagnosis of giant cell arteritis. All patients had complete clinical and biological response to corticoids. PET controls performed 3- to 6-months post-treatment, confirmed the disappearance of the metabolic stigma. CONCLUSION: 18FDG PET may show an increased glucose metabolism in asymptomatic extracranial vessels locations of Horton's arterities. If these observations are confirmed on controlled trials, PET could be particularly useful for non-invasive diagnosing, staging and monitoring atypical clinical forms of Horton's disease. The metabolic imaging could also contribute to a better understanding of the pathogenesis of GCA.

Aged↗
PubMed2002

Positron emission tomography (PET) evaluation of abdominal aortic aneurysm (AAA).

BACKGROUND: aneurysmal disease is associated with an inflammatory cell infiltrate and enzymatic degradation of the vessel wall. AIM OF THE STUDY: to detect increased metabolic activity in abdominal aortic aneurysms (AAA) by means of positron emission tomography (PET-imaging). STUDY DESIGN: twenty-six patients with AAA underwent PET-imaging. RESULTS: in ten patients, PET-imaging revealed increased fluoro-deoxy-glucose (18-FDG) uptake at the level of the aneurysm. Patients with positive PET-imaging had one or more of the following elements in their clinical history: history of recent non-aortic surgery (n = 4), a painful inflammatory aortic aneurysm (n = 2), moderate low back pain (n = 2), rapid (> 2;5 mm in 6 months) expansion (n = 4), discovery by PET-scan of a previously undiagnosed lung cancer (n = 3) or parotid tumour (n = 1). Five patients with a positive PET scan required urgent surgery within two to 30 days. Among the 16 patients with negative PET-imaging of their aneurysm, only one had recent non-aortic surgery, none of them required urgent surgery, only two had a rapidly expanding AAA, and in only one patient, PET-imaging revealed an unknown lung cancer. CONCLUSION: these data suggest a possible association between increased 18-FDG uptake and AAA expansion and rupture.

Aged↗
PubMed2002

Fluorodeoxyglucose positron emission tomography and somatostatin receptor scintigraphy for diagnosing and staging carcinoid tumours: correlations with the pathological indexes p53 and Ki-67.

We performed this study in order to evaluate the diagnostic accuracy of whole-body fluorodeoxyglucose positron emission tomography (FDG PET) imaging and somatostatin receptor scintigraphy (SRS) for localizing primary carcinoid tumours and evaluating the extent of the disease. A secondary aim was to correlate those findings with the histological characteristics of the lesions. FDG PET was performed in 17 patients and SRS in 16. All patients had pathologically proven carcinoids. All lesions were verified by histopathological analysis or by follow-up. Ki-67 and p53 expression were assessed as an indicator of the tumours' aggressiveness. FDG PET correctly identified 4/7 primary tumours and 8/11 metastatic spreads, as compared to six and 10 respectively, for SRS. Most tumours were typical carcinoids with low Ki-67 expression. No correlation was found between the histological features and the tracer's uptake. We conclude that SRS remains the modality of choice for evaluating patients with carcinoid tumours, regardless of their proliferative activity. FDG PET should be reserved to patients with negative results on SRS.

Adult↗
PubMed2002

Gamma-probe-directed lymphatic mapping and sentinel lymphadenectomy in primary cutaneous melanoma.

BACKGROUND: Radiotracer and blue-dye lymphatic mapping is a recommended combined method to guide sentinel lymphadenectomy and full regional lymph node dissection in selected patients with cutaneous melanoma. OBJECTIVE: To evaluate the diagnostic accuracy and the prognostic value of gamma-probe-directed lymphatic mapping in cutaneous melanomas. METHODS: Sixty-five stage I and II melanoma patients underwent gamma-probe-directed lymphatic mapping. Sentinel lymph nodes were studied by both conventional and immunohistochemical stainings. The median follow-up was 11 months. RESULTS: Sensitivities of preoperative and intraoperative sentinel lymph node detection were 100 and 98%, respectively. Only 1 failure of detection and 1 missed same-basin metastasis were experienced in the axillary and cervical areas, respectively. Eleven patients (16.9%) had sentinel node metastases leading to adjuvant therapy. CONCLUSION: Gamma-probe-directed lymphatic mapping is useful for staging melanoma. However, in the expectation of a more specific identification of the sentinel lymph node, the standard protocol remains recommended for exploring the axillary and cervical areas. The histological examination supported in some cases by immunohistochemistry remains mandatory in all cases.

Female↗
PubMed2001

Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) for the staging of low-grade non-Hodgkin's lymphoma (NHL).

BACKGROUND: Although PET has been shown to be highly sensitive in the primary staging of lymphoma, previous studies with small numbers of patients indicated that low-grade NHL may not always be adequately detected by PET. We undertook this study to determine factors influencing the detection of lesions by PET in low-grade NHL and to evaluate the utility of PET in this indication. PATIENTS AND METHODS: Forty-two patients underwent conventional staging procedures (clinical examination, oto-rhino-laryngologic examination, computed tomography of the chest, abdomen and pelvis, gastroscopy and bone marrow biopsy as well as whole-body non-attenuation corrected 18F-FDG-PET RESULTS: PET detected 40% more abnormal lymph node areas than conventional staging in follicular lymphoma but was inappropriate for the staging of small lymphocytic lymphoma where it detected less than 58% of abnormal lymph node areas. PET showed more lesions than conventional staging for peripheral (34% more lymph node areas detected) and thoracic lymph node (39% more) areas but not for abdominal or pelvic lymph nodes (26% fewer areas detected). The sensitivity to detect bone marrow infiltration was unacceptably low for PET. In contrast, PET was as effective as standard procedures for the detection of other extranodal localizations, although a few localizations were detected only by PET and a few others only by conventional procedures. CONCLUSIONS: PET may contribute to the management of patients with low-grade follicular NHL. For the other low-grade lymphoma subtypes, the role of PET is less evident. Further studies using PET to evaluate the results of treatment or to diagnose disease recurrence are warranted in low-grade follicular NHL.

Adult↗
PubMed2001

Positron emission tomography (PET) for staging low-grade non-Hodgkin's lymphomas (NHL).

Although positron emission tomography (PET) imaging is now recognized as a useful tool for staging intermediate and high-grade non-Hodgkin's lymphoma (NHL), few data are available regarding its accuracy in low grade NHL. We therefore studied 36 patients with histologically proven low-grade NHL. Whole-body 2-(fluorine-18) fluoro-2-deoxy-D-glucose (FDG) PET was performed at the time of initial diagnosis (n = 21) or for disease recurrence (n = 15) prior to any treatment. PET results were compared to those of physical examination and computed tomography (CT). PET studies were read without knowledge of any clinical data. Any focus of increased activity was described and given a probability of malignancy using a 5 point-scale (0: normal to 4: definitively malignant). An individual biopsy was available for a total of 31 lesions. The sensitivity and specificity were 87% and 100% for FDG-PET, 100% and 100% for physical examination and 90% and 100% for CT respectively. In addition, 42 of 97 peripheral lymph node lesions observed by FDG-PET were clinically undetected, whereas the physical examination detected 23 additional nodal lesions. PET and CT both indicated 12 extranodal lymphomatous localizations. FDG-PET showed 7 additional extranodal lesions while 5 additional unconfirmed lesions were observed on CT. Regarding bone marrow infiltration, PET and biopsy were concordant in 24 patients with 11 true positive (TP) and 13 true negative (TN). However PET was FN in 11 patients and no biopsy was performed in one patient. The combination PET/CT/physical examination seems to be more sensitive than the conventional approach for staging low grade NHL. Its sensitivity however is unacceptably low for diagnosing bone marrow infiltration.

Adult↗
PubMed2001

Dobutamine stress echocardiography versus quantitative technetium-99m sestamibi SPECT for detecting residual stenosis and multivessel disease after myocardial infarction.

OBJECTIVE: To compare the relative accuracy of dobutamine stress echocardiography (DSE) and quantitative technetium-99m sestamibi single photon emission computed tomography (mibi SPECT) for detecting infarct related artery stenosis and multivessel disease early after acute myocardial infarction. DESIGN: Prospective study. SETTING: University hospital. METHODS: 75 patients underwent simultaneous DSE and mibi SPECT at (mean (SD)) 5 (2) days after a first acute myocardial infarct. Quantitative coronary angiography was performed in all patients after imaging studies. RESULTS: Significant stenosis (> 50%) of the infarct related artery was detected in 69 patients. Residual ischaemia was identified by DSE in 55 patients and by quantitative mibi SPECT in 49. The sensitivity of DSE and mibi SPECT for detecting significant infarct related artery stenosis was 78% and 70%, respectively, with a specificity of 83% for both tests. The combination of DSE and mibi SPECT did not change the specificity (83%) but increased the sensitivity to 94%. Mibi SPECT was more sensitive than DSE for detecting mild stenosis (73% v 9%; p = 0.008). The sensitivity of DSE for detecting moderate or severe stenosis was greater than mibi SPECT (97% v 74%; p = 0.007). Wall motion abnormalities with DSE and transient perfusion defects with mibi SPECT outside the infarction zone were sensitive (80% v 67%; NS) and highly specific (95% v 93%; NS) for multivessel disease. CONCLUSIONS: DSE and mibi SPECT have equivalent accuracy for detecting residual infarct related artery stenosis of >/= 50% and multivessel disease early after acute myocardial infarction. DSE is more predictive of moderate or severe infarct related artery stenosis. Combined imaging only improves the detection of mild stenosis.

Adult↗
PubMed2001

Whole-body positron emission tomography using 18F-fluorodeoxyglucose compared to standard procedures for staging patients with Hodgkin's disease.

BACKGROUND AND OBJECTIVES: Accurate staging is essential in order to determine appropriate treatment in Hodgkin's disease (HD). (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) offers the advantage of metabolic imaging that is largely independent of morphologic criteria. In the present study we evaluated the role of (18)F-FDG PET compared to routine procedures for the staging of patients with HD. DESIGN AND METHODS: Thirty-three patients with HD underwent standard staging procedures (clinical examination, laboratory screening, chest X-ray, computed tomography (CT) of the chest and abdomen and bilateral bone marrow biopsies) and a whole-body (18)F-FDG PET study. In clinical examination, an isolated lymph node > 1 cm or multiple lymph nodes > or = 1 cm in size were considered abnormal. Positive findings at both clinical examination or CT and (18)F-FDG PET were regarded as actual locations of disease. Negative findings with both methods were regarded as true negative (no involvement by HD). In cases of discrepancy, response to treatment and follow-up data were used to assess the overall accuracy of the patient's original evaluation. RESULTS: Completely concordant results in lymph node staging were observed in 20 patients. The two staging procedures indicated complementary information in 1 patient. Conventional staging indicated more pathologic lymph node areas in 6 patients (at least 1 false positive). (18)F-FDG PET showed more sites in 6 patients. The sensitivity of (18)F-FDG PET in detecting all known pathologic lymph nodes was 83% for peripheral lymph nodes, 91% for thoracic lymph nodes and 75% for abdominal and pelvic lymph nodes. Conventional staging procedures and (18)F-FDG PET indicated the same tumor stage in 26 patients. Based on (18)F-FDG PET, downstaging was suggested in 4 patients, including a biopsy-proven case. However in 1 of these cases this was incorrect. (18)F-FDG PET suggested upstaging in 3 patients. Based on conventional staging or (18)F-FDG PET the same treatment strategy was defined in 32 patients. In one patient (18)F-FDG PET downstaged disease extension (stage IIIA-->IIA) that would have suggested radiotherapy as a possible treatment option. INTERPRETATION AND CONCLUSIONS: (18)F-FDG PET provides an easy and efficient whole-body method for the evaluation of patients with HD. (18)F-FDG PET never missed tumor masses >1 cm. (18)F-FDG PET detected additional sites of disease not seen by conventional procedures and identified absence of disease in some sites suspected to be involved. However, in our patients this did not translate into changes in treatment strategy.

Adolescent↗
PubMed2000

Automatic quantification of defect size using normal templates: a comparative clinical study of three commercially available algorithms.

Infarct size assessed by myocardial single-photon emission tomography (SPET) imaging is an important prognostic parameter after myocardial infarction (MI). We compared three commercially available automatic quantification algorithms that make use of normal templates for the evaluation of infarct extent and severity in a large population of patients with remote MI. We studied 100 consecutive patients (80 men, mean age 63 +/- 11 years, mean LVEF 47% +/- 15%) with a remote MI who underwent resting technetium-99m tetrofosmin gated SPET study for infarct extent and severity quantification. The quantification algorithms used for comparison were a short-axis algorithm (Cedars-Emory quantitative analysis software, CEqual), a vertical long-axis algorithm (VLAX) and a three-dimensional fitting algorithm (Perfit). Semiquantitative visual infarct extent and severity assessment using a 20-segment model with a 5-point score and the relation of infarct extent and severity with rest LVEF determined by quantitative gated SPET (QGS) were used as standards to compare the different algorithms. Mean infarct extent was similar for visual analysis (30% +/- 21%) and the VLAX algorithm (25% +/- 17%), but CEqual (15% +/- 11%) and Perfit (5% +/- 6%) mean infarct extents were significantly lower compared with visual analysis and the VLAX algorithm. Moreover, infarct extent determined by Perfit was significantly lower than infarct extent determined by CEqual. Correlations between automatic and visual infarct extent and severity evaluations were moderate (r = 0.47, P < 0.0001 to r = 0.62, P < 0.0001) but comparable for all three algorithms. Correlations between LVEF and visual evaluation of infarct extent (r = -0.80, P < 0.0001) and severity (r = -0.82, P < 0.0001) were good but correlations were significantly lower for all three algorithms (r = -0.48, P < 0.0001 to r = -0.65, P < 0.0001). Systematically lower correlations were found in non-anterior infarctions (n = 69) and obese patients (BMI > or = 30 kg/m2, n = 32) compared with anterior infarctions and non-obese patients for all three algorithms. In this large series of post-MI patients, results of infarct extent and severity determination by automatic quantification algorithms that make use of normal templates were not interchangeable and correlated only moderately with semiquantitative visual analysis and LVEF.

Adult↗
PubMed2000

An appraisal of 18-fluorodeoxyglucose positron emission tomography for melanoma staging.

BACKGROUND: Positron emission tomography (PET scan) using fluorodeoxyglucose (FDG) is increasingly recognized as a reliable diagnostic method to detect metastases of malignant melanoma (MM). OBJECTIVE: To compare the diagnostic performance of 18-FDG PET scan to that of conventional imaging. METHODS: A total of 28 assessments were conducted in 24 patients at risk of metastatic MM. RESULTS: The diagnostic accuracy was over 80% and similar for PET scan and conventional imaging. CONCLUSION: Both the specificity and sensitivity of PET scan are high although not perfect. Confrontation of data with anatomical location and clinicopathological findings remains mandatory.

Humans↗
PubMed2000

[18FDG-PET imaging of pancreatic adenocarcinoma].

FDG-PET imaging non invasively studies the glucose metabolism which is usually increased in malignant lesions. We evaluated the clinical performance of PET for detecting pancreatic cancer and its recurrence. In our series of 24 studies, PET appears to complement other imaging modalities. As compared to CT, in particular, it demonstrated fewer false positive results in the pancreas and it was also more sensitive. Moreover, whole-body FDG-PET allows for the entire staging of the disease.

Adenocarcinoma↗
PubMed2000

[Diagnosis of primary hyperparathyroidism: role of scintigraphy].

We report a case of hyperparathyroidism whose diagnosis was suspected by a clinical history and confirmed by routine laboratory tests. Scintigraphy has permitted to localize a focalized lesion corresponding to an adenoma endocrinopathy. The new developments of this imaging technique will be discussed further. Some aspects of physiopathology will be briefly considered and a therapeutic algorithm will be proposed.

Adenoma↗
PubMed2000

[Contribution of positron emission tomography for the management of lung cancer].

18 FDG- PET is an imagining technique based on metabolic criteria rather than morphological criteria. (18) FDG- PET can demonstrate accelerated glycosis in cancer tissue related to increased transporter and glycolytic enzyme activity. Whole body PET is currently under validation in a growing number of indications during diagnostic and therapeutic assessment phases of cancer treatment. In the field of pulmonary oncology, (18) FDG- PET has already demonstrated its performance capacity to: 1) discriminate the malignant nature of a solitary pulmonary nodule, 2) improve sensitivity over CT for mediastinal assessment in small-cell lung cancer, 3) acquire whole body imaging to search for distant metastasis in patients with small-cell lung cancer; PET is particularly useful for evaluation of an adrenal mass, 4) complement CT imaging to better dissociate tumor residue or recurrence from post-therapeutic sequelae in small-cell lung cancer. Information provided by (18) FDG- PET is thus clinically relevant as it allows better dissociation of a benign process from a malignant process and better precision of small-cell lung cancer extension without necessitating systematic invasive exploration.

Bronchial Neoplasms↗
PubMed2000

[How I investigate ... a broncho-pulmonary cancer by metabolic imaging (PET-18-FDG)].

Continuing advances in PET imaging have resulted in an improved ability to evaluate thoracic malignancies. Published reports demonstrate that PET provides accurate noninvasive detection of malignancy that is useful in the characterization of a pulmonary solitary nodule and in the mediastinal or extrathoracic staging of known lung cancer. Preliminary studies suggest that PET may also be able to assess the therapeutic response after surgery or radiation therapy.

Diagnosis, Differential↗