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J Leclère

Publications and source records attributed to J Leclère.

At least 19 recordsLinked to original sources
PubMed2006

Improving the interpretation of bone marrow imaging in cancer patients.

Magnetic resonance imaging (MRI) is the best technique for bone marrow imaging. The MRI signal of bone marrow depends on the quantity of fat it contains and on its cellularity. Evaluation of marrow of patients treated for cancer is complicated by age and osseous site related changes in the distribution of normal haematopoietic (red) and fatty (yellow) marrow and by the changes induced by treatments: decrease in pathological cellularity, increase in fat proportion, conversion of red marrow to fatty marrow or, conversely, reconversion of fatty marrow in normal haematopoietic red marrow. The treatments used in oncology modify pathological marrow but also normal marrow and may sometimes lead to complications. These modifications may be focal or diffuse, homogeneous or patchy and symmetrical or asymmetric. The knowledge of bone marrow physiological status and post-therapeutic patterns is important for the interpretation of marrow disorders and effects of therapy and to avoid false-positive diagnosis of marrow metastases and tumour progression. The aim of this paper is to recall the MRI patterns of normal bone marrow and normal variations and to show the effects of treatments on bone tissue and normal bone marrow and treatment-related modifications on pathological marrow.

Antineoplastic Agents↗
PubMed2006

[Communication between radiologist and cancer patients].

Along with advances in medicine and social evolution, we are seeing an increase in the number of patients afflicted with cancer, and a change in the doctor-patient relationship. Patients' rights are now registered in the Hospitalised Patient's Charter, the Huriet Act and the Act of March 4, 2002. The evolution in cancer diseases is monitored by a range of imaging examinations, putting the radiologist in the front line. Lesions are typically first detected by the radiologist. This task is complicated by the fact that radiologists usually have no formal training with regards to the disclosure of cancer diagnoses to patients. There is a great risk of inappropriate responses which can have a profoundly damaging effect on the patient's state of mind. Even if we have the best of ideals and intentions, there is a great need for us to examine and improve our modes of interaction, in dealing with the patient's need for information. The radiologist possesses technical know-how, but technique alone is not enough - the right amount of information, based on clinical competence, is required; but so is empathy towards the patient, and respect for his or her wishes and rights.

Communication↗
PubMed2006

[Improving overall patient care during imaging studies: the radiologist's CREDO and PERLES].

The protocols specifying the basic rules of the doctor-patient relationship that have been proposed in the literature are primarily intended for referring physicians, in particular oncologists. With regard to the improving radiologists' communication skills, a simple tool, RADPED, was developed to help residents in pediatric radiology to memorize the main points of the patient-radiologist interaction. We suggest a protocol, CREDO, more precisely appropriated to the everyday practice of medical imaging, in particular in oncology. This protocol relates not only to the radiologist-patient relationship, but also to the rules common to the department's entire team. The aims are to establish a partnership with the patient (for this purpose, we suggest using the PERLES model: partnership, excuses (apology), respect, legitimization, empathy, support), carrying out the examination under optimal conditions, listening to what the patient has to say, giving information and, above all, organizing the imaging department around the patient.

Clinical Protocols↗
PubMed2005

Doctor-patient relationship in oncologic radiology.

Progress in medicine and changes in our society have led to an increasing number of patients with cancer and a change in the doctor-patient relationship. Patients rights are now defined in several countries by laws. The course of cancer involves numerous imaging examinations in which the radiologist is primarily involved. It is often the radiologist who discovers abnormalities and who must break the news to the patient. This task is made all the more difficult by the radiologist's lack of specific training in the management of difficult situations such as announcing bad news. There is a high risk of inappropriate responses that can have a seriously damaging effect on the patient's state of mind. Even with the best intentions, it can be very profitable to review and improve our relational modalities and to more effectively meet the patient's increasing demand for information. The radiologist's technical know-how is not sufficient, as he must also be able to give just the right amount of information based on his clinical competence, and his relationship with patients while respecting their wishes and their rights.

Humans↗
PubMed2005

Role of contrast-enhanced color Doppler ultrasonography and dynamic flow in the evaluation of hepatic tumors treated with radiofrequency.

The contribution of contrast-enhanced color Doppler ultrasonography (CDUS) and dynamic flow (DF) (Toshiba) in the evaluation following treatment of hepatic tumors with radiofrequency (RF) is discussed. Twenty-seven patients with 34 hepatic tumors were included in this prospective study. The treated tumors measured 10-58 mm in diameter (mean diameter 29 mm). Two tumors were treated twice and one three times, comprising a total of 38 target lesions treated with RF and evaluated by 127 contrast-enhanced CDUS. The results of CDUS follow-up were compared to those of the dynamic MRI at 2 months, 4 months, 6 months and 1 year. Before RF, the injection of Levovist raised the number of vascularized lesions seen with unenhanced Doppler from 44% to 79%. All the non-vascularized lesions were metastases. Twenty-four hours after RF, four tumors presented an enhancement with Levovist, in which two were insufficiently treated lesions. Twenty-one treated tumors have been followed-up jointly by CDUS and MRI at the same time at 2 months, 20 at 4 months, 12 at 6 months and nine at 1 year. Compared to the MRI and the evolution, the CDUS presented a sensitivity of 100% and a specificity of 90% for the detection of progressive recurrence. The preliminary results show that the CDUS is useful to confirm the absence of detectable vascularity after treatment with RF ablation, whereas the presence of enhancement must be confirmed by MRI.

Adult↗
PubMed2005

Imaging in evaluation of response to neoadjuvant breast cancer treatment.

The role of imaging for patients treated with neoadjuvant therapy for breast cancer is not only to evaluate the therapeutic response in terms of tumour shrinkage, but also to predict the histological response to chemotherapy, which is correlated to survival. Surgery and histopathological analysis after neoadjuvant therapy allow for an objective assessment of the accuracy of imaging techniques in evaluating response. The aim of this study is to compare the value of the different conventional and functional imaging techniques for determining response to neoadjuvant chemotherapy in breast cancer treatment.

Breast Neoplasms↗
PubMed2004

[Functional and early evaluation of treatments in oncology: interest of ultrasonographic contrast agents].

The early and functional evaluation of new treatments in oncology is a main goal. At present, technical advances in Doppler-ultrasonography allow the detection of neovascularization for superficial and deep malignant tumors in order to evaluate the efficiency of new treatments as Treatment response can be early predicted according to modifications of this vascularization before Volume modification. Contrast agents injection improves the efficiency of this technique and developments in perfusion softwares optimize this detection.

Adult↗
PubMed2003

[Treatment of local recurrent melanomas by isolated limb perfusion: value of Doppler ultrasonography].

PURPOSE: To assess the effectiveness of Color Doppler Ultrasound (US) in the follow-up of recurrent melanoma of the limbs treated by isolated limb perfusion (ILP). MATERIALS AND METHODS: A retrospective study was done looking at 18 patients treated by isolated perfusion of the limb. Number, size and vascularity of subcutaneous metastases were examined for all patients. The results of pre and post therapeutic examinations were compared with clinical data and evolution. RESULTS: US was superior to clinical examination in the detection and measurement of subcutaneous metastases. Decrease in tumor size and early disappearance of tumoral vascularity were associated with an effective tumor response to treatment. Early disappearance of vascularity was associated with early complete response. Initial presence or persistence of vascularity before the third month after treatment were not poor prognostic factors. The appearance of vascularity seemed to be an indicator of early failure of the treatment. CONCLUSION: Color Doppler US is highly effective for the follow-up of patients with recurrent melanoma of the limbs. It provides prognostic factors of treatment failure, which may lead to early modification of the treatment strategy.

Adult↗
PubMed2001

The fluorescence of advanced Maillard products is a good indicator of lysine damage during the Maillard reaction.

The objective of this study was to determine whether in heat-treated milk-resembling models or milk there is a lag phase, before lactulosyllysine (LL) is converted into advanced Maillard products (AMP), and if there is a step during the heat treatment where LL is actively degraded into AMP. For that purpose, a low temperature (60-85 degrees C) and a long heat treatment (15-90 h) were chosen. We observe that the heat treatment first induces a parallel increase in furosine and AMP fluorescence, confirming that AMP are produced very early during the heat treatment. At this step, both indicators are correlated with each other and precisely reflect the lysine damage. After a time, however, furosine reaches a steady-state concentration, whereas AMP fluorescence still increases, remaining correlated with the lysine blockage. Nevertheless, heat treatment applied to milk does not reach this step so that AMP fluorescence appears as a rapid alternative to furosine quantification.

Animals↗
PubMed2001

Increased expression of the vascular endothelial growth factor is a pejorative prognosis marker in papillary thyroid carcinoma.

Vascular endothelial growth factor (VEGF) is a potent stimulator of endothelial cell proliferation. It has been implicated in tumor growth of human thyroid carcinomas. Using the VEGF immunohistochemistry staining score, we correlated the level of VEGF expression with the metastatic spread of 19 cases of thyroid papillary carcinoma. The VEGF immunostaining score, ranging from 0-9, was determined as the multiplication of a percentage of labeled thyrocytes score (0, no labeling; 1, <30%; 2, 31--60%; 3, >61% of labeled thyrocytes) and an intensity score (0, no staining; 1, weak; 2, mild; 3, strong staining). The mean score +/- SD was 5.74 +/- 2.59 for all carcinomas. The mean score for metastatic papillary carcinoma was 8.25 +/- 1.13 vs. 3.91 +/- 1.5 for nonmetastatic papillary cancers (P < 0.001). By discriminant analysis, we found a threshold value of 6.0, with a sensitivity of 100% and a specificity of 87.5%. There were no statistical differences between metastatic and nonmetastatic carcinomas when age, tumor size, or thyroglobulin levels were considered. The VEGF immunostaining score seems to be a helpful marker for metastasis spread in differentiated thyroid cancers. An increased production of VEGF could assess an aggressive disease and be the hallmark of a trend to produce metastasis. We propose the VEGF immunostaining score as a marker for the prognosis in differentiated thyroid cancers. A value of 6 or more, should be considered as at high risk for metastasis threat, prompting the physician to institute a tight follow up of the patient.

Adolescent↗
PubMed2000

Factors of variation and reference values for TSH in 45-70 year old women.

Thyroid stimulating hormone (TSH) was measured in a sample of 4,403 women, aged 45-70 years in 11 Centers for health screening, to define the interest of this biological indicator for screening subclinical hypothyroidism. The aim of this work was to describe clinical signs, symptoms and medical history linked to TSH variations, to estimate the distribution of this hormone in a general population and reference limits in a selected subgroup. All the participating laboratories used the same third-generation immunoassay on fresh samples. In the general sample population (age mean: 55.2 6.9 yrs), 1.1% presented hyperthyroidism (TSH<0.3 mU/l) and 0.4% had hypothyroidism (TSH>12 mU/l). In the sub-sample of 151 women (3.4%) with TSH between 4-12 mU/l, 131 had subclinical hypothyroidism (FT4>8 ng/l). The TSH mean was significantly lower (- 10 to - 23%) in women presenting a nodular goiter. Inversely, TSH was higher in women with muscle cramps, asthenia, recent weight gain, morning eyelid edema and abnormal electrocardiogram. The reference limits for percentiles 2.5 and 97.5 were 0.43 and 3.71 mU/l on 1 348 subjects after excluding women having one of these symptoms or taking any drug treatment.

Aged↗
PubMed1999

Selective estrogen receptor modulators.

Selective estrogen receptor modulators are a growing class of nonsteroidal compounds with estrogen-like actions in bone, lipid metabolism, and antiestrogenic actions in the breast. Tamoxifen and its derivatives have a weak estrogenic action in the uterus and are responsible for endometrial hyperplasia. Raloxifene does not stimulate endometrial growth but is less effective than tamoxifen for the treatment of patients with breast cancer. The duality of selective estrogen receptor modulators and 1 7B-estradiol actions is explained by several hypotheses referring to the molecular biology of estrogen receptor. Clinical trials are conducted with raloxifene in post-menopausal women. The results show a significant decrease in vertebral fracture risk and a decrease of low-density lipoprotein cholesterol, with no change in triglyceride levels. Endometrial thickness does not change. Interestingly, the risk for newly diagnosed breast cancer decreases significantly with no change in risk for estrogen receptor-negative tumors. Selective estrogen receptor modulators might change the way we manage hormone replacement therapy of postmenopausal women.

Bone Density↗
PubMed1999

New hemodynamic approach to angiogenesis: color and pulsed Doppler ultrasonography.

RATIONALE AND OBJECTIVES: To determine the capacity of color and spectral Doppler ultrasonography (US) to quantify angiogenesis in vivo and to characterize low-resistance intratumor blood flow. METHODS: Thirty-two tumors, xenografted into mice, were studied with Doppler US. The number of intratumor vessels visualized with color Doppler US was compared with the density of microvessels and the number of vessels >100 microm determined by histologic examination. The resistance index and the peak systolic velocities were evaluated. RESULTS: The number of intratumor vessels visualized by color Doppler US was correlated with the number of vessels >100 microm (P<0.001) determined histologically. When vessel density was >30, intratumor vessels were always detected by color Dopper US. The resistance index and peak systolic velocities were significantly lower in intratumor than in peritumor vessels. CONCLUSIONS: Color Doppler US evaluated tumor angiogenesis accurately. Spectral analysis confirmed the low resistance of intratumor blood flow.

Animals↗
PubMed1999

Vascular endothelial growth factor gene and protein: strong expression in thyroiditis and thyroid carcinoma.

Angiogenesis is implicated in several pathological conditions, such as inflammation and tumor growth. Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, is a potent stimulator of endothelial cell proliferation in vitro and in vivo. The present work aimed to compare VEGF expression in human normal thyroid glands, thyroiditis tissue and thyroid carcinomas using immunohistochemistry and in situ hybridization (ISH). Both chronic lymphocytic thyroiditis and differentiated thyroid carcinomas were found to strongly express VEGF mRNA and encode larger amounts of VEGF than normal thyroid tissue as attested by a VEGF immunostaining score. In addition, tumor samples from patients with metastases showed a higher immunostaining score than their non-metastatic counterparts (P<0.05). Carcinomas with the greatest contents of VEGF mRNA and VEGF protein had the most intense mitogenic activity. Special focus on endothelial cells showed intense mitogenic activity in neoplastic tissues in contrast to the total quiescence of endothelial cells in non-tumoral tissues. An intense VEGF production by differentiated thyroid carcinoma, attested either by a higher immunostaining score or a strong VEGF mRNA expression using ISH, could be a promising marker of tumor aggressiveness and may also be useful as a predictor of metastatic potential.

Adult↗
PubMed1999

Prognostic value of high-frequency sonography and color Doppler sonography for the preoperative assessment of melanomas.

OBJECTIVE: The purposes of this study were to determine the efficacy of high-frequency sonography for the preoperative assessment of melanomas and to determine the prognostic value of tumor vascularity measured by color Doppler sonography. SUBJECTS AND METHODS: Twenty-seven patients with melanomas were prospectively examined using high-frequency sonography before they underwent surgery. For each tumor, morphologic evaluation (20-MHz probe), including the measurement of maximum tumor thickness, and color Doppler sonography analysis (13-MHz probe), including the measurement of intratumor vascularity, were performed. Diagnosis was confirmed by histologic findings, tumor thickness was measured using the Breslow index, and vascularity was assessed by immunochemical findings. RESULTS: Each of the 27 melanomas was depicted on high-frequency sonography as a homogeneous hypoechoic structure with well-defined margins. Tumor thickness was measured using high-frequency sonography as ranging from 0.3 to 8.0 mm, whereas it was measured using the Breslow index as ranging from 0.26 to 8.0 mm. Sonography measurements and Breslow index values were strongly correlated (r > .95). In the cases in which the Breslow index value exceeded 1 mm (n = 11), surgical reexcision was necessary but could have been avoided if surgery had been planned on the basis of high-frequency sonography measurements. Intratumor vessels were depicted on color Doppler sonography (n = 10). Color Doppler sonography data and histologic findings were significantly correlated. CONCLUSION: High-frequency sonography is a simple, reliable, noninvasive, and accurate method for the preoperative measurement of melanoma thickness. In fact, surgical planning could be adapted according to this measurement. The prognostic value of vascularization evaluated with color Doppler sonography is comparable with that determined by the Breslow index.

Aged↗
PubMed1999

[Urinary lithiasis: between metabolism and dietetics].

Prevalence and incidence of urinary lithiasis are increasing in western countries. Oxalocalcic stone is the major form of urinary calculi but other forms are not unusual. Caracteristics of the collected stone may improve the diagnosis investigations. Rationnal blood and urine examinations are essential for this medical managment. Most of the various metabolic abnormalities in cause can be corrected from specific dietary measures.

Calcium↗
PubMed1998

[Diagnosis of hypothyroidism in the adult].

Hypothyroidism is a common endocrine disease, specially in women after the age of fourty. The clinical manifestations may be insensitive, aspecific or absent, which may impair diagnosis. Clinical, anamnestical and biological features may lead to a diagnostical suspicion that needs to be confirmed by a determination of serum TSH. Serum TSH determination allows the early recognition of subclinical hypothyroidism. However the signification of this moderate increase in TSH level is controversial, and uncertainty remains over the benefits of treating such patients yielding slightly elevated TSH concentration. Hypothyroidism is usually caused by a primary autoimmune thyroid disease, and seldom due to central hypothalamic or pituitary disorder.

Adult↗