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C Calmettes

Publications and source records attributed to C Calmettes.

At least 37 records · Page 2Linked to original sources
PubMed1989

Early calcitonin hypersecretion and C cell hyperplasia in rats with high incidence of C cell tumors (Wag/Rij).

Wag/Rij rats, a Wistar-derived strain, develop on aging a spontaneous medullary thyroid carcinoma which shows many morphological similarities to the human neoplasm. Using biochemical and histological methods, we studied calcitonin secretion and C cell distribution in young and adult Wag/Rij rats, to characterize possible modifications in calcitonin synthesis and secretion as compared to the original Wistar strain. During the period investigated, the mean basal circulating levels of calcitonin of both sexes were not significantly different between the two strains, although the Wag/Rij rats tended to have higher values. After a calcium challenge, the circulating calcitonin levels increased normally in the Wag/Rij strain as compared to Wistar rats of the same ages. Histological observations of their thyroids revealed a significant C cell hyperplasia, along with a weak immunostaining in some of the cells, due to a lack of secretory granules. Thus, in addition to the ability of developing C cell tumours on aging, the Wag/Rij strain is characterized by an early C cell hyperplasia leading to an increase of calcitonin secretion after a provocative secretion test.

Aging↗
PubMed1989

Multiple endocrine neoplasia type II: clinical, biological and epidemiological features. French Medullary Study Group.

Medullary thyroid carcinoma (MTC) is a particularly interesting model of gene expression in cancer. As a matter of fact, it is remarkable from many points of view: it occurs in two forms: (1) MTC only or part of a multiple endocrine neoplasia II (MEN II), and (2) it is sporadic or inherited and benefits from a specific and sensible marker, calcitonin; the gene responsible for the hereditary form is localized on chromosome 10. Taking into account clinical, biological, genealogical and epidemiological features of the disease as supporting one another, a French collective study has been initiated; preliminary analysis of data allows to conclude on the value of such national collaboration for early diagnosis, prognosis and estimation of the incidence of the disease.

Carcinoma↗
PubMed1989

Screening for medullary thyroid cancer in France: a national effort. French Medullary Study Group (GETC).

Screening for medullary thyroid cancer (MTC) in France is based on a protocol that has been widely distributed nationally. A network of coordinators utilizing a common questionnaire provides for an effective national screening program. Calcitonin stimulation procedures are systematically used for all first-degree relatives of MTC patients. Pathological studies utilize special immunopathologic techniques. Genealogic information is obtained on all index cases, and blood specimens are collected for establishing permanent cell lines. The data collected are used not only to establish the diagnosis of the hereditary or sporadic form of the disease but also to expand the screening as appropriate. This common protocol has benefited patients and their families by improving early detection of cases, increasing the number of families available for follow-up, and improving the prognosis of this cancer. Studies on these families have contributed significantly to the localization of the multiple endocrine neoplasia type 2 gene.

France↗
PubMed1989

Screening for medullary cancer of the thyroid in France.

Screening of medullary cancer of the thyroid (MCT) in France relies on a collaborative work since 1982. The diagnosis of the index case relies on the detection of calcitonin in the tumor as well as on assay of circulating CT. A common protocol is used for patients and families. The familial screening is systematically carried out, even in apparently sporadic MCTs. A pentagastrin CT stimulation test is asked for all family members, whatever the age. All the data are collected by regional coordinators and centralized in a national register. Until 1987, 1031 MCT cases have been recorded, including 226 familial cases belonging to 62 families (29 MCT only, 29 MEN IIa and 4 MEN IIb).

Carcinoma↗
PubMed1988

[Medullary cancer of the thyroid. Apropos of 20 years' experience in France].

The majority (1013) of cases of medullary carcinoma of the thyroid observed in France in the last twenty years have been registered in a national file. Once overcome the difficulty of diagnosing the index case, all first degree parents at least should undergo a pentagastrin stimulation test and calcitonin estimation. Though such a policy involves difficulties of several types, it has resulted in the detection of 203 cases belonging to 61 families. 29 families suffered only from isolated MCT; in the 32 other families this cancer was a part of polyendocrinopathies of type 2a (28 cases) or type 2b (4 cases). The tumour was apparently of the sporadic type in 208 subjects. In 602 other cases the data were insufficient for a correct classification. An epidemiological enquiry of the disease is in progress since 1986. Though the number of complete files analysed is still insufficient, this study will be essential in understanding the natural history of the disease, the causes of its heterogeneity and in deducing eventually preventive measures even if in meantime a genetic marker is available.

Carcinoma↗
PubMed1988

[Endocrine polyadenomatosis of 2a type (MEN 2a). Clinical and genetic study of a family].

In a large kindred with multiple endocrine neoplasia type 2a (MEN 2a) (137 members, 5 generations), bilateral thyroid medullary carcinoma was found in all affected members. Pheochromocytoma was present in 59% of the cases, and was responsible at least for 4 out the 5 deaths related to MEN 2a. Hyperparathyroidism was less frequent (41%). Family screening leads to a reduction in age for diagnosis and to an improvement in the prevalence of complete healing after surgery. Linkage between HLA loci and a dominant gene for MEN 2a was investigated in this kindred. Lod scores for recombination fraction were all negative (-0.47 for a recombination fraction of 0.05). These results comfort the lack of linkage between MEN 2a and the HLA complex.

Adolescent↗
PubMed1986

Uptake of 131I-MIBG by medullary carcinoma of thyroid in familial cases.

Medullary carcinoma of the thyroid (MCT) and pheochromocytoma are APUD tumors. MIBG (Meta Iodo Benzyl Guanidine) uptake by pheochromocytomas is now well known but very few cases of MIBG uptake in sporadic MCT have been described. We report here the two first cases of inherited MCT with MIBG uptake.

3-Iodobenzylguanidine↗
PubMed1986

[Hemothorax disclosing hemorrhagic necrosis of a pheochromocytoma: circumstance for detection of multiple endocrine neoplasia type IIa. Detection of 5 familial cases].

Whilst investigating 26 members of the same family, we discovered 5 cases of multiple endocrine neoplasia type II a. The present report demonstrates the diagnostic value of basal plasma thyrocalcitonin (TCT) assays, before and after stimulation with pentagastrin, and of plasma carcinoembryonic antigen (CEA) assays. Some of the clinical features encountered were novel--e.g. in one patient the phaeochromocytoma was revealed by a haemothorax with cardiovascular collapse--and others were peculiar; thus, in 4 cases the medullary thyroid carcinoma (MTC) was less than 2 cm in diameter and without lymph node or visceral metastases, even in patients aged 87, 59 and 56. More classically, MTC, always multifocal, was clinically silent, as were the two cases of phaeochromocytoma and hyperparathyroidism. Phaeochromocytomas were difficult to diagnose. Ultrasonic tomography did not prove very helpful and the disease was transmitted as an autosomal dominant trait. Finally, MTC secreted a variety of substances (TCT, CEA, beta-endorphin, somatostatin), and HLA A2-B15 antigens were found in 3 patients.

Adrenal Gland Neoplasms↗
PubMed1985

On the presence of autoantibodies in the plasma of patients suffering from medullary carcinoma of the thyroid.

Thyroiditis is associated with certain cases of medullary carcinoma of the thyroid (MCT). In order to determine if this was due to the presence of autoantibodies, we have investigated whether plasma from patients suffering from the disease contain autoantibodies. The specificity of the reaction was established using specific antibodies to antigens such as: calcitonin (CT), carcinoembryonic antigen (CEA) and thyroglobulin (Tg); no antibodies against CT, CEA or Tg were detected in the plasma from the patients investigated. The presence of autoantibodies to a constituent of the tumor was established in each case studied. The detection of autoantibodies to a "specific" constituent of MCT could be of potential interest in the early screening for the disease.

Antibodies, Neoplasm↗
PubMed1984

[Calcitonin cancers: definition, history, various forms].

Calcitonin secreting tumors, as their name indicates, share a common denominator; yet, their clinical, morphological and biochemical features are polymorphous. Medullary thyroid carcinoma is a well-known disease, with sporadic and familial forms, associated or not with type II multiendocrinopathy; not only calcitonin and carcinoembryonic antigen, its reliable markers, but also multiple other hormones may be secreted. Atypical forms, more or less undifferentiated, even heterogenous may also exist: the presence of the hormone in tumoral cells allows their recognition. Moreover, ectopic calcitonin secretion may be related to quite different tumors with regard to their clinic, pathologic, embryologic aspects. Thus, strict criteria are necessary for their diagnosis. Molecular biology will certainly help the understanding of the functional and genetic aspects of these tumors.

Calcitonin↗
PubMed1984

[Use of thyrocalcitonin for the detection of familial medullary cancers in children].

The preoperative diagnosis of medullary thyroid carcinoma (MTC) can be made by measuring serum calcitonin levels (CT). If the patient has a thyroid nodule--sporadic or familial MTC--the serum CT will be raised but in the familial form of the disease, the diagnosis should be made at a much earlier, subclinical stage when surgery can be curative: this is possible when raised hormone levels are observed after stimulation tests. However, as this form of cancer sometimes presents late, repeated stimulation tests are necessary, with all the difficulties that it implies, in all patients with normal hormone levels in whom it is impossible to exclude tumoral heredity, whether they belong to a family with a case of sporadic MTC or to a healthy branch of a family affected by heredity.

Calcitonin↗
PubMed1984

[Analysis of circulating calcitonin for the detection of familial and sporadic medullary cancer].

Medullary carcinoma of the thyroid is always linked to a high basal level of calcitonin or to an abnormal increase of the hormone after stimulation: this is generally the case in incipient tumoral metastases and in sub-clinical familial cases. Moreover, a normal stimulation test does not allow to eliminate the probability of a tumoral heredity and it is often difficult to discriminate between sporadic and familial cases or normal and high risk subjects during familial screening. So, in the absence of established rules of follow-up, repetitive stimulation tests will be often necessary as well as an extensive investigation of members of the families.

Calcitonin↗