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C Schvartz

Publications and source records attributed to C Schvartz.

18 recordsLinked to original sources
PubMed2006

Survival of cancer patients in France: a population-based study from The Association of the French Cancer Registries (FRANCIM).

We present the main results of the first population-based cancers survival study gathering all French registry data. Survival data on 205,562 cancer cases diagnosed between 01/01/1989 and 31/12/1997 were analysed. Relative survival was estimated using an excess rate model. The evolution of the excess mortality rate over the follow-up period was graphed. The analysis emphasised the effect of age at diagnosis and its variation with time after diagnosis. For breast and prostate cancers, the age-standardised five-year relative survivals were 84% and 77%, respectively. The corresponding results in men and women were 56% versus 58% for colorectal cancer and 12% versus 16% for lung cancer. For some cancer sites, the excess mortality rate decreased to low values by five years after diagnosis. For most cancer sites, age at diagnosis was a negative prognostic factor but this effect was often limited to the first year after diagnosis.

Adolescent↗
PubMed2006

[Predictive value and sensibility of hospital discharge system (PMSI) compared to cancer registries for thyroïd cancer (1999-2000)].

BACKGROUND: Cancer registries have a complete recording of new cancer cases occurring among residents of a specific geographic area. In France, they cover only 13% of the population. For thyroid cancer, where incidence rate is highly variable according to the district conversely to mortality, national incidence estimates are not accurate. A nationwide database, such as hospital discharge system, could improve this estimate but its positive predictive value and sensibility should be evaluated. METHODS: The positive predictive value and the sensitivity for thyroid cancer case ascertainment (ICD-10) of the national hospital discharge system in 1999 and 2000 were estimated using the cancer registries database of 10 French districts as gold standard. The linkage of the two databases required transmission of nominative information from the health facilities of the study. From the registries database, a logistic regression analysis was carried out to identify factors related to being missed by the hospital discharge system. RESULTS: Among the 973 standardized discharge charts selected from the hospital discharge system, 866 were considered as true positive cases, and 107 as false positive. Forty five of the latter group were prevalent cases. The predictive positive value was 89% (95% confidence interval (CI): 87-91%) and did not differ according to the district (p=0,80). According to the cancer registries, 322 thyroid cancer cases diagnosed in 1999 or 2000 were missed by the hospital discharge system. Thus, the sensitivity of this latter system was 73% (70-76%) and varied significantly from 62% to 85% across districts (p<0.001) and according to the type of health facility (p<0.01). CONCLUSION: Predictive positive value of the French hospital discharge system for ascertainment of thyroid cancer cases is high and stable across districts. Sensitivity is lower and varies significantly according to the type of health facility and across districts, which limits the interest of this database for a national estimate of thyroid cancer incidence rate.

Age Factors↗
PubMed2004

[Prevention of recurrent amiodarone-induced hyperthyroidism by iodine-131].

Amioradone-induced hyperthyroidism is a common complication of amiodarone therapy. Although definitive interruption of amiodarone is recommended because of the risks of aggravation of the arrhythmias, some patients may require the reintroduction of amiodarone several months after normalisation of thyroid function. The authors undertook a retrospective study of the effects of preventive treatment of recurrences of amiodarone-induced hyperthyroidism with I131. The indication of amiodarone therapy was recurrent, symptomatic, paroxysmal atrial fibrillation in 13 cases and ventricular tachycardia in 5 cases (M = 14, average age 64 +/- 13 years). The underlying cardiac disease was dilated cardiomyopathy (N = 5), ischaemic heart disease (N = 3), hypertensive heart disease (N = 2), arrhythmogenic right ventricular dysplasia (N = 2) or valvular heart disease (N = 2). Two patients had idiopathic atrial fibrillation. An average dose of 576 +/- 184 MBq of I131 was administered 34 +/- 37 months after an episode of amiodarone-induced hyperthyroidism. Amiodarone was reintroduced in 16 of the 18 patients after a treatment-free period of 98 +/- 262 days. Transient post-radioiodine hyperthyroidism was observed in 3 cases (17%). Sixteen patients (89%) developed hypothyroidism requiring replacement therapy with L-thyroxine. There were no recurrences of amiodarone-induced hyperthyroidism. After 24 +/- 17 months follow-up, the arrhythmias were controlled in 13 of the 16 patients (81%) who underwent the whole treatment sequence. The authors conclude that preventive treatment with I131 is an effective alternative to prevent recurrence of amiodarone-induced hyperthyroidism in patients requiring reintroduction of amiodarone to control their arrhythmias.

Adult↗
PubMed2003

Second primary malignancies in thyroid cancer patients.

The late health effects associated with radioiodine ((131)I) given as treatment for thyroid cancer are difficult to assess since the number of thyroid cancer patients treated at each centre is limited. The risk of second primary malignancies (SPMs) was evaluated in a European cohort of thyroid cancer patients. A common database was obtained by pooling the 2-year survivors of the three major Swedish, Italian, and French cohorts of papillary and follicular thyroid cancer patients. A time-dependent analysis using external comparison was performed. The study concerned 6841 thyroid cancer patients, diagnosed during the period 1934-1995, at a mean age of 44 years. In all, 17% were treated with external radiotherapy and 62% received (131)I. In total, 576 patients were diagnosed with a SPM. Compared to the general population of each of the three countries, an overall significantly increased risk of SPM of 27% (95% CI: 15-40) was seen in the European cohort. An increased risk of both solid tumours and leukaemias was found with increasing cumulative activity of (131)I administered, with an excess absolute risk of 14.4 solid cancers and of 0.8 leukaemias per GBq of (131)I and 10(5) person-years of follow-up. A relationship was found between (131)I administration and occurrence of bone and soft tissue, colorectal, and salivary gland cancers. These results strongly highlight the necessity to delineate the indications of (131)I treatment in thyroid cancer patients in order to restrict its use to patients in whom clinical benefits are expected.

Adolescent↗
PubMed2003

Cancer incidence and mortality in France over the period 1978-2000.

BACKGROUND: Monitoring cancer incidence and mortality time trends is essential for cancer research and health-care planning. French cancer registries do not cover the entire population and do not provide a representative sample of the national population. Our study aimed at estimating national cancer incidence and mortality trends over the longest period available. METHODS: Incidence and mortality data were collected over the period 1978-1997. Twenty-seven cancer sites were selected and age, sex and site specific incidence and mortality rates were estimated for each year from 1978 up to 2000. Observed incidence and mortality data in the population covered by cancer registries were modelled using age-cohort methods. An estimation of the incidence/mortality ratio was obtained from these models and applied to the mortality rates predicted from an age-cohort model for the entire French population. The person-years of observation were calculated cohort-wise from census data provided by the national institute of statistics RESULTS: Cancer incidence increased by 63% throughout the study period, from 170,000 new cases in 1980 to 278,000 in 2000. This evolution was due to demographic changes but also to an increase in the risk of cancer which was estimated to more than 35% during the same period. In men, this change is largely explain by the increase of prostate cancer incidence. Among women, the increase was dominated by the continuing increase in breast cancer incidence. Large increases were also seen for non-Hodgkin lymphoma, melanoma, and thyroid cancer in both genders and for lung cancer in women. Cancer mortality increased by 20% from 125,000 deaths in 1980 to 150,000 in 2000. This increase is less than that predicted from changes in demographic factors and corresponds in fact to a decrease in the risk of death estimated to about 8%, slightly greater for women than for men. This decrease is associated with a decreasing incidence for stomach cancers for both sexes, alcohol-related cancer for men and cervical cancer for women. Colo-rectal cancer decreasing mortality contributes to this improvement despite an incidence increase. CONCLUSION: Between 1980 and 2000, the study showed a large change in the cancer burden both quantitatively and qualitatively. Decrease in exposure, earlier diagnosis and therapeutic improvement explained part of this change, but overall the distribution of cancer cases shifted toward a distribution including less aggressive cancers. A striking divergence between incidence and mortality trends is observed for a great number of cancers. Prostate cancer shares with breast cancer the same pattern of a severe increasing incidence and a stable mortality. This points to important changes in medical practice and needs further analysis. The trend of lung cancer mortality among women should be emphasised since the situation will inevitably worsen in the coming years. It is already the third cause of cancer death among women.

Age Distribution↗
PubMed2002

Incidence of thyroid cancer in adults recorded by French cancer registries (1978-1997).

This article analyses time trends and geographical variations of thyroid cancer by histological type. Incidence data were provided by 8 French cancer registries over the period 1978-1997, with 3853 adult cases reported. To assess the effects of age, period, cohort and area on incidence, log-linear Poisson regression models were used. Thyroid cancer increased exponentially from the cohort born in 1925. This increase was essentially due to papillary cancer, which increased by 6.2% per year in men and 8.1% per year in women over the entire period (1978-1997). In women, the recent trends were significantly different between the studied geographical areas. The analysis shows that the increase in thyroid cancer, essentially of the papillary type, is not recent. It may be attributed to a possible screening effect or to an increase in the number of "incidentally" discovered cases linked to the use of modern diagnostic tools.

Adenoma↗
PubMed2001

Clinical impact of (18)F-FDG PET in thyroid carcinoma patients with elevated thyroglobulin levels and negative (131)I scanning results after therapy.

UNLABELLED: 18F-FDG PET has been shown to effectively detect differentiated thyroid carcinoma (DTC) metastases with impaired iodine-trapping ability. This article evaluates the potential contribution of FDG PET in the follow-up of patients with differentiated thyroid carcinoma, elevated thyroglobulin (Tg) levels, and negative whole-body scan results obtained after high doses of (131)I. METHODS: We prospectively assessed the ability of FDG to detect metastases in 37 DTC patients who had undergone total thyroidectomy and radioactive ablation and presented with persistent disease, as assessed from elevated Tg levels and negative results of whole-body scans performed after therapeutic doses of (131)I. Additional conventional imaging procedures were performed to detect residual disease, and the patients were divided into 2 groups: group 1, with positive conventional imaging findings (n = 10), and group 2, with negative conventional imaging findings (n = 27). RESULTS: FDG PET showed positive findings in 28 patients and accurately localized tumor sites in 89% of them. In group 1, FDG PET confirmed 17 of 18 previously known tumor sites and detected 11 additional sites. In group 2, FDG PET findings were positive in 19 of 27 patients with no previously detected metastases. PET was effective for both low- and high-stage tumors. The FDG data led to a change in the clinical management of 29 of 37 patients with further surgical resection in 23 patients, 14 of whom achieved disease-free status, and external radiation therapy in 4 patients. CONCLUSION: FDG PET is able to detect metastases undetected by (131)I posttherapy whole-body scanning in patients with elevated Tg levels. It should be proposed as a first-line investigation in patients with persistent disease but negative findings on (131)I whole-body scans after treatment.

Adult↗
PubMed2000

[Positive antithyroglobulin antibodies in patients with differentiated thyroid carcinoma. What significance?].

The aim of this retrospective study was to determine the predictive value of antithyroglobulin antibodies (TgAb) in 238 patients with undetectable thyroglobulin after whole thyroidectomy for differentiated cancer and ablative dose of radioiodine. TgAb titers were elevated in 30 patients with undetectable Tg level after withdrawal of T4 treatment. In 21 patients, initially positive TgAb titers became undetectable without clinical event within 3-84 months after therapy (median 12 months). In 2 cases, TgAb levels became undetectable whereas scintigraphy detected pathologic fixations. In 7 cases, high levels of TgAb titles remained unchanged 5 years after primary diagnosis In 3 of them, clinical course and distant metastases, were associated with an increased TgAb level despite normal Tg values. The investigation confirmed that serum TgAb measurement is one of the most important tools for the follow-up of patients with differentiated thyroid cancer. The presence of metastatic thyroid tissue has to be suspected in positive TgAb patients.

Adolescent↗
PubMed1997

Thoracic and abdominal SPECT-CT image fusion without external markers in endocrine carcinomas. The Group of Thyroid Tumoral Pathology of Champagne-Ardenne.

UNLABELLED: Superimposition of SPECT and computed tomography (CT) slices from the thoracoabdominal region was achieved without the use of external markers for 14 studies in 13 patients with endocrine carcinoma. Technical feasibility and clinical validation of this retrospective fusion method were assessed. METHODS: Patients had a history of thyroid cancer or of carcinoid tumor. To detect tumor sites, CT scan and dual-isotope tomoscintigraphy were performed, with 99mTc-hydroxymethylene diphosphonate for bone scintigraphy and with 111In-pentetreotide, 131I or 131I-metaiodobenzylguanidine for tumor scintigraphy (TS). A superimposition method previously developed for the pelvic region was adapted to the nonrigid thoraco-abdominal region. CT-bone scintigraphy and CT-TS superimposed images were obtained. Clinical validation of the information obtained from the superimposed images was obtained from surgery or follow-up imaging studies performed after clinical evolution of the disease process. RESULTS: Reliable and reproducible registration was achieved in all patients. CT-TS superimposed images produced accurate localization of abnormal TS foci. Accuracy was limited primarily by variable relative displacements of the thoracoabdominal organs. For 10 sites in 8 patients, localization and/or characterization obtained from CT-TS images was confirmed by a reference technique. Superimposition enabled the localization of tumor sites that otherwise could not have been suspected from CT alone and allowed the characterization of CT suspicious masses and the confirmation of CT positive sites. Nonspecific tumor TS uptake sites were also localized. CONCLUSION: With standard CT and dual-isotope SPECT acquisitions, SPECT-CT fusion is feasible in the thoracoabdominal region without the use of external markers. Fused images were validated in 8 patients for 10 sites. The use of this technique could probably improve the management and care of patients with endocrine carcinoma.

3-Iodobenzylguanidine↗
PubMed1996

Functional characteristics of three new germline mutations of the thyrotropin receptor gene causing autosomal dominant toxic thyroid hyperplasia.

We report three unrelated families in which hyperthyroidism associated with thyroid hyperplasia was transmitted in an autosomal dominant fashion, in the absence of signs of autoimmunity. Exon 10 of the TSH receptor gene was directly sequenced after PCR amplification from DNA of peripheral leukocytes. In one family, a C to A transversion resulted in an S505R substitution in the third transmembrane segment; in the second, an A to T transversion caused a N650Y substitution in the sixth transmembrane segment; and in the third family, an A to G transition resulted in an N670S substitution in the seventh transmembrane segment. When expressed by transfection in COS-7 cells, each mutated receptor displayed an increase in constitutive stimulation of cAMP production; no effect on basal accumulation of inositol phosphates (IP) could be detected. In binding studies, cells transfected with wild-type or mutated receptors showed similar levels of expression, with the mutated receptors displaying similar or slightly increased affinity for bovine TSH (bTSH) binding. Cells transfected with S505R and N650Y mutants showed a similar cAMP maximal TSH-stimulated accumulation over the cells transfected with the wild type, whereas N670S transfectants showed a blunted response with an increase in EC50. A higher IP response to 100 mU/mL bTSH over that obtained with the wild-type receptor was obtained in cells transfected with N650Y; in contrast, cells transfected with S505R showed a blunted IP production (50% less), and the N670S mutant completely lost the ability to stimulate IP accumulation in response to bTSH. The differential effects of individual mutations on stimulation by bTSH of cAMP or IP accumulation suggest that individual mutant receptors may achieve different active conformations with selective abilities to couple to Gs alpha and to Gq alpha.

Amino Acid Sequence↗
PubMed1996

[Cancers of the thyroid. Value of a regional registry on 627 patients diagnosed, treated and followed by a multidisciplinary team].

Since 1966, data from 1536 patients with a thyroid carcinoma, living in the French region Champagne-Ardenne, a geographical area with 1,350,000 inhabitants were registered. The creation of a multidisciplinary group and the involvement of the general practitioners, allowed us to reach an exhaustive and continued registration process for the French administrative area of Marne and Ardennes (855,000 inhibitants, 627 patients). The sex-ratio F/M was 3.8 and the median ages were respectively equal to 46 [10-93] and 52 [13-82] in females and males. In the age groups 10-14 and 15-19, 3 cases and 13 cases were respectively registered. An history of external irradiation was noted in 2.9% of the patients. The study of the incidence around the Chooz nuclear plant (Ardennes) did not show an increase of the risk. For the French administrative area Marne and Ardennes, for the period 1975-1979, the incidence rates, standardized on the European population, were equal to 1.75/100,000 in males (SD = 0.15) and 6.38/100,000 (SD = 0.29) in females. These values among the highest from the data published by the other European registries should be explained by a more intensive diagnosis procedure and an improvement in the accuracy of histological diagnosis. An increase of the incidence rate was observed between the periods 1975-1983 and 1984-1992 from 1.04 to 2.05/100,000 and 4.99 to 6.39/100,000 in males and females respectively. This was associated with changes in clinical and histological features and an improvement in survival curves. For patients under the age of 19, we have compared both periods before and after the accident of Chernobyl. The incidence rates increased from 0.13 to 0.45/100,000 and 0.49 to 1.81/100,000 in the age groups 10-14 and 15-19 respectively. This change was at the order of magnitude to this observed in our adults population. We did not found the histological aggressiveness which characterized the Chernobyl-induced thyroid cancer in children. The knowledge of the significant prognostic factors determined by multifactorial analyses is a major foundation of our therapeutic strategy.

Adolescent↗
PubMed1996

[131 iodine and differentiated thyroid cancers].

By its dual gamma and beta emission, 131I permits both external detection and selective irradiation of residual or metastatic differentiated thyroid carcinoma. Indications based on the evaluation of prognostic factors and on the quality of surgical excision are more advisable than systematic use. Useless, even harmful after unilateral surgery decided because of a very good prognosis, 131I is recommended according to several retrospective studies for post surgical ablation of the remnants, the detection and the treatment of the recurrences and the distant metastases. The use of therapeutic doses in patients with an isolated elevation of thyroglobuline (Tg) without any clinical or radiological signs favors early diagnosis and cure of metastases with negative diagnostic scintigraphy. Dosimetric considerations and radioprotection measures must be guided by specific rules concerning radiometric material, adapted rooms and skilful personnel. Scintigraphic detection must be done in the best technical conditions. Protracted follow-up is based on Tg dosages and 131I whole body scintigraphies. Early diagnosis of metastases and positive response to 131I irradiation influence favorably remission rates. Even if a complete remission is not achieved, repeated treatments by a specialized team improve the quality of survival for metastatic patients.

Adult↗
PubMed1994

Germline mutations in the thyrotropin receptor gene cause non-autoimmune autosomal dominant hyperthyroidism.

The thyrotropin receptor (TSHR), a member of the large family of G protein-coupled receptors, controls both the function and growth of thyroid cells via stimulation of adenylyl cyclase. We report two different mutations in the TSHR gene of affected members of two large pedigrees with non-autoimmune autosomal dominant hyperthyroidism (toxic thyroid hyperplasia), that involve residues in the third (Val509Ala) and seventh (Cys672Tyr) transmembrane segments. When expressed by transfection in COS-7 cells, the mutated receptors display a higher constitutive activation of adenylyl cyclase than wild type. This new disease entity is the germline counterpart of hyperfunctioning thyroid adenomas, in which different somatic mutations with similar functional characteristics have been demonstrated.

Adenoma↗
PubMedDate not supplied

[Value of parathyroid scintigraphy in preoperative localization of parathyroid adenoma. Study apropos of 138 tests].

The authors have studied, about a total of 138 exams, the value of parathyroid nuclide scan. All the patients, who had primary hyper parathyroidism, have been operated upon. The results of parathyroid scintigraphy have been compared to the results of surgical exploration. Overall sensibility of the exam has been 80%, better with the MIBI (89%) than with the Thallium (78%). The specificity has also been better with the MIBI (95%) than with the Thallium (87%) with a global result of 88%). Computerized treatment of images with automatized subtraction especially studied in Institut Jean-Godinot, Rheims, explain the quality of these results.

Adenoma↗