Are dietary reports in a case-control study on thyroid cancer biased by risk perception of Chernobyl fallout?

BACKGROUND: In retrospective case-control studies performed following nuclear tests or nuclear accidents, individual thyroid radiation dose reconstructions are based on fallout and meteorological data from the residential area, demographic characteristics, and lifestyle as well as dietary information. Collecting the latter is a controversial step, as dietary declarations may be affected by the subjects' beliefs about their risk behavior. This report analyses the potential for such bias in a case-control study performed in eastern France. METHODS: The study included 765 cases of differentiated thyroid carcinoma matched with 831 controls. Risk perceptions and beliefs of cases and controls were compared using Chi2 tests and differences in dietary reports were analyzed using a two-way ANOVA. RESULTS: In general, atmospheric pollution and living near a nuclear power plant were the two major risks that may influence thyroid cancer occurrence cited by cases and controls. When focusing in particular on the consequences of the Chernobyl accident, cases were more likely to think that the consequences were responsible for thyroid cancer occurrence than controls. Vegetable consumption during the two months after the Chernobyl accident was correlated with the status of subjects, but not to their beliefs. Conversely, consumption of fresh dairy products was not correlated with the status or beliefs of subjects. CONCLUSION: We found no evidence of systematic bias in dietary reports according to the status or beliefs held by subjects about the link between thyroid cancer occurrence and Chernobyl fallout. As such, these dietary reports may be used in further studies involving individual dosimetric reconstructions.

Recent trends in incidence, geographical distribution, and survival of papillary thyroid cancer in France.

BACKGROUND: Over the past few decades, the incidence of thyroid cancer has dramatically increased in many countries. This increase was mainly seen in papillary cancer. The role of diagnostic practices and the effects of other risk factors were suggested to explain this increase. We provide a descriptive analysis in terms of changes in incidence, geographical distribution, and survival to check the relevance of assumptions about the increase. METHODS: A detailed analysis of changes in incidence recorded in French cancer registries between 1982 and 2010 was performed taking into account age, period, and birth cohort. The geographical distribution of the incidence in the 2006-2010 period was estimated from the standardized incidence ratios. The net survival was estimated to evaluate the effects of sex, age, and period of diagnosis in patients diagnosed between 1989 and 2004 and followed-up until 2013. RESULTS: The incidence of papillary cancer has increased sharply over the 1982-2010 period; the average annual rate of increase was 7.8% in men and 7.2% in women. The increase has slowed in the recent period in people aged less than 50 at the time of diagnosis. It has also slowed in the cohorts born 1945 and after. There was a strong geographic disparity in incidence between areas covered by cancer registries. Finally, the net survival was very high; the 10-year net survival was 96% and improved progressively from 82% in patients diagnosed between 1989 and 1993 to 95% in those diagnosed between 1999 and 2004. CONCLUSION: The increased incidence results most probably from the effect of medical practice, although other risk factors seem also involved, but to a lesser extent. The increase seems to have slowed down in the recent years, especially in the youngest age groups. This observation suggests a recent trend towards saturation of the effects of medical practices in post-1945 cohorts associated with an effect of the gradual dissemination of the recommendations relative to the management of thyroid nodules.

Long-term follow-up of patients with papillary and follicular thyroid cancer: a prospective study on 715 patients.

PURPOSE: This prospective study evaluated the recurrence rate in 715 patients with differentiated thyroid cancer who had no evidence of persistent disease after total thyroidectomy and lymph node dissection in 94% of them followed up by radioiodine ablation (30-100 mCi) and assessed the predictive value of the initial thyroglobulin (Tg) levels for detecting recurrence, both during levothyroxine (LT4) treatment and after TSH stimulation. PATIENTS AND METHODS: Patients had Tg determinations performed at 3 months on LT4 treatment (Tg1) and at 9-12 months after stimulation by either thyroid hormone withdrawal or recombinant human TSH (Tg2); the Access kit was used (functional sensitivity of 0.11 ng/ml); they had undetectable anti-Tg antibodies. Patients were followed up annually. Predictive values were calculated by comparing Tg levels (Tg1 and Tg2) and the outcome in terms of recurrence. RESULTS: During the median follow-up of 6.2 yr, 32 patients had a recurrence. Assuming a cutoff level for Tg1 at 0.27 ng/ml, Tg1 sensitivity and specificity reached 72 and 86%, respectively, whereas predictive positive and negative values were 20 and 99%, respectively. With a cutoff level for Tg2 at 1.4 ng/ml, sensitivity and specificity reached 78 and 90%, respectively, whereas positive and negative predictive values were 26 and 99%, respectively. CONCLUSION: This large prospective cohort of patients presented a low rate of recurrence. Initial Tg measurements allow to predict long-term recurrence with an excellent specificity. Stimulated Tg determination presented a slightly higher sensitivity than Tg determination on LT4. TSH stimulation may be avoided when Tg measured 3 months after ablation is less than 0.27 ng/ml during LT4 treatment.

Prognostic factors of disease-free survival after thyroidectomy in 170 young patients with a RET germline mutation: a multicenter study of the Groupe Francais d'Etude des Tumeurs Endocrines.

BACKGROUND: In hereditary medullary thyroid carcinoma (HMTC), prophylactic surgery is the only curative option, which should be properly defined both in time and extent. OBJECTIVES: To identify and characterize prognostic factors associated with disease-free survival (DFS) in children from HMTC families. DESIGN: We conducted a retrospective analysis of a multi-center cohort of 170 patients below age 21 at surgery. Demographic, clinical, genetic, biological data [basal and pentagastrine-stimulated calcitonin (CT and CT/Pg, respectively)], and tumor node metastasis (TNM) status were collected. DFS was assessed based on basal CT levels. Kaplan-Meier curves, Cox regression, and logistic regression models were used to determine factors associated with DFS and TNM staging. RESULTS: No patients with a preoperative basal CT <31 ng/ml had persistent or recurrent disease. Medullary thyroid carcinoma defined by a diameter ≥10 mm [hazard ratio (HR): 6.0; 95% confidence interval (95% CI): 1.8-19.8] and N1 status (HR: 20.8; 95% CI: 3.9-109.8) were independently associated with DFS. Class D genotype [odds ratio (OR): 48.5, 95% CI: 10.6-225.1], preoperative basal CT >30 ng/liter (OR: 43.4, 95% CI: 5.2-359.8), and age >10 (OR: 5.5, 95% CI: 1.4-21.8) were associated with medullary thyroid carcinoma ≥10 mm. No patient with a preoperative basal CT <31 ng/ml had a N1 status. Class D genotype (OR: 48.6, 95% CI: 8.6-274.1), and age >10 (OR: 4.6, 95% CI: 1.1-19.0) were associated with N1 status. CONCLUSION: In HMTC patients, DFS is best predicted by TNM staging and preoperative basal CT level below 30 pg/ml. Basal CT, class D genotype, and age constitute key determinants to decide preoperatively timely surgery.

[Time trends in the geographic variation of thyroid cancer incidence by tumor size from 1983 to 2000 in France]. / Disparités géographiques d'évolution d'incidence des cancers de la thyroïde par taille entre 1983 et 2000 en France.

BACKGROUND: The aim of this investigation was to study geographic time trends of thyroid cancer incidence according to tumor size in France, 1983 to 2000. METHODS: Incidence data were provided from six French registries over the period 1983-2000 covering seven administrative districts. Five tumor size groups were distinguished: < 10mm, 10-20mm, 20-40mm, > 40mm and unknown size. Papillary cancers diagnosed in women were analyzed according to tumor size in each geographic area. World age standardized rates were calculated and annual percent change rates were estimated for each tumor size group in each geographic area. Loglinear Poisson regression models were used to study geographic discrepancies in time trends incidences. RESULTS: The six French registries included 2222 papillary thyroid cancers in women between 1983 et 2000. Thyroid cancer incidence was increasing in the six geographic areas. Geographical variations in time trends incidence between registries reflected geographical variations in time trends incidence of small sized tumors (less than 10mm). CONCLUSION: Wide geographic variations in thyroid cancer incidence were noticed for small size tumors, which may be correlated with geographic variations in medical practices.

Cancer incidence and mortality in France over the period 1980-2005.

BACKGROUND: The objective of this study was to provide updated estimates of national trends in cancer incidence and mortality for France for 1980-2005. METHODS: Twenty-five cancer sites were analysed. Incidence data over the 1975-2003 period were collected from 17 registries working at the department level, covering 16% of the French population. Mortality data for 1975-2004 were provided by the Inserm. National incidence estimates were based on the use of mortality as a correlate of incidence, mortality being available at both department and national levels. Observed incidence and mortality data were modelled using an age-cohort approach, including an interaction term. Short-term predictions from that model gave estimates of new cancer cases and cancer deaths in 2005 for France. RESULTS: The number of new cancer cases in 2005 was approximately 320,000. This corresponds to an 89% increase since 1980. Demographic changes were responsible for almost half of that increase. The remainder was largely explained by increases in prostate cancer incidence in men and breast cancer incidence in women. The relative increase in the world age-standardised incidence rate was 39%. The number of deaths from cancer increased from 130,000 to 146,000. This 13% increase was much lower than anticipated on the basis of demographic changes (37%). The relative decrease in the age-standardised mortality rate was 22%. This decrease was steeper over the 2000-2005 period in both men and women. Alcohol-related cancer incidence and mortality continued to decrease in men. The increasing trend of lung cancer incidence and mortality among women continued; this cancer was the second cause of cancer death among women. Breast cancer incidence increased regularly, whereas mortality has decreased slowly since the end of the 1990s. CONCLUSION: This study confirmed the divergence of cancer incidence and mortality trends in France over the 1980-2005 period. This divergence can be explained by the combined effects of a decrease in the incidence of the most aggressive cancers and an increase in the incidence of less aggressive cancers, partly due to changes in medical practices leading to earlier diagnoses.

Comparison of seven serum thyroglobulin assays in the follow-up of papillary and follicular thyroid cancer patients.

BACKGROUND: Serum thyroglobulin (Tg) is the marker of differentiated thyroid cancer after initial treatment and TSH stimulation increases its sensitivity for the diagnosis of recurrent disease. AIM: The goal of the study is to compare the diagnostic values of seven methods for serum Tg measurement for detecting recurrent disease both during L-T4 treatment and after TSH stimulation. METHODS: Thyroid cancer patients who had no evidence of persistent disease after initial treatment (total thyroidectomy and radioiodine ablation) were studied at 3 months on L-T4 treatment (Tg1) and then at 9-12 months after withdrawal or recombinant human TSH stimulation (Tg2). Sera with anti-Tg antibodies or with an abnormal recovery test result were excluded from Tg analysis with the corresponding assay. The results of serum Tg determination were compared to the clinical status of the patient at the end of follow-up. RESULTS: Thirty recurrences were detected among 944 patients. A control 131I total body scan had a low sensitivity, a low specificity, and a low clinical impact. Assuming a common cutoff for all Tg assays at 0.9 ng/ml, sensitivity ranged from 19-40% and 68-76% and specificity ranged from 92-97% and 81-91% for Tg 1 and Tg2, respectively. Using assays with a functional sensitivity at 0.2-0.3 ng/ml, sensitivity was 54-63% and specificity was 89% for Tg1. Using the two methods with a lowest functional sensitivity at 0.02 and 0.11 ng/ml resulted in a higher sensitivity for Tg1 (81% and 78%), but at the expense of a loss of specificity (42% and 63%); finally, for these two methods, using an optimized functional sensitivity according to receiver operating characteristic curves at 0.22 and 0.27 ng/ml resulted in a sensitivity at 65% and specificity at 85-87% for Tg1. CONCLUSION: Using an assay with a lower functional sensitivity may give an earlier indication of the presence of Tg in the serum on L-T4 treatment and may be used to study the trend in serum Tg without performing any TSH stimulation. Serum Tg determination obtained after TSH stimulation still permits a more reliable assessment of cure and patient's reassurance.

A time trend analysis of papillary and follicular cancers as a function of tumour size: a study of data from six cancer registries in France (1983-2000).

The incidence of thyroid cancers, and in particular the papillary forms, has been increasing sharply for many years in Western countries. However, the factors explaining this increase have not been clearly established. Some studies mention the effects of radioactive fallout, particularly after the accident in Chernobyl. Another probable cause is related to progress in medical practice, and particularly in diagnosis. In this article, we describe time trends in the incidence of papillary and follicular cancers, taking into account the size of the tumour at the time of diagnosis. The analysis was carried out on cases from six French cancer registries for the period 1983-2000. Anatomopathological reports concerning 3381 cancer cases were systematically recoded and centralised, following ICDO-3 rules. Over the whole period, the annual percent change of the incidence of papillary cancers was +8.13% and +8.98%, respectively in men and in women. For micropapillary carcinomas (< or = 10 mm), this increase was respectively +12.05% and +12.85%. There is no significant effect of period apart from micropapillary carcinomas in women. However, a birth cohort effect exists for some groups. This effect corresponds to an acceleration in the risk for people born after the 1930s. For the most recent period (1998-2000), half the cases of papillary cancer were micropapillary carcinomas, and for one third of these, the tumour was < or = 5 mm. Our description of a time trend of incidence as a function of tumour size supports the hypothesis of the role of medical practice in a context of high prevalence. Obviously, these findings do not exclude the possible role of other factors.

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.

[Predictive value and sensibility of hospital discharge system (PMSI) compared to cancer registries for thyroïd cancer (1999-2000)]. / Valeur prédictive et sensibilité du programme de médicalisation des systèmes d'information (PMSI) par rapport aux registres des cancers: application au cancer de la thyroïde (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.

[Prevention of recurrent amiodarone-induced hyperthyroidism by iodine-131]. / Prévention des récidives d'hyperthyroïdie a l'amiodarone par l'iode131.

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.

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.

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.

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.

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.

[Positive antithyroglobulin antibodies in patients with differentiated thyroid carcinoma. What significance?]. / Présence d'anticorps antithyroglobuline chez les patients suivis pour cancer différencié de la thyroïde. Quelle signification?

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.

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.

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.

[Cancers of the thyroid. Value of a regional registry on 627 patients diagnosed, treated and followed by a multidisciplinary team]. / Les cancers de la thyroïde. Intérêt d'un registre régional de 627 patients diagnostiqués, traités et suivis par une équipe multidisciplinaire.

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.