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In response to the French hospital system crisis and the challenges faced by the heads of departments, we have undertaken an initiative to create a community of heads of haematology departments willing to assist each other. Our inaugural seminar, held in January 2023, established the foundational "core" group of heads of department. Throughout 2023, this emerging community has prospered, offering sustained support to peers. In January 2024, we broadened our community to include other heads of departments, following a second seminar gathering 36 participants. During this event, we took the time to exchange thoughts and reflect on our missions. Building on the experience of guest speakers and employing methods of co-development and co-construction in plenary sessions, small-group workshops, and social gathering, we were able to discover and experience the collective intelligence, creativity, strength, and support stemming from such a group. This peer community of heads of departments stands as a powerful tool for management support, whereby personal experiences nourish and enrich the experience of others. We hope that our initiative will inspire heads of departments from other specialties so that, together, we can better work towards our missions as heads of departments and collaborate on rebuilding the hospital "from the bottom up"., (Copyright © 2024 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

Calcitonin (CT), a hypocalcemic and hypophosphatemic hormone, is produced by the C-cells of the thyroid gland. It is the main tumoral marker of medullary thyroid carcinoma (MTC). Hypersecretion of CT is also associated with other types of tumors. Thus, heterogeneity of circulating CT can play an important role in the accurate determination of hormone levels in blood samples obtained from MTC patients. Further studies will be necessary to establish the predictive value of the several peptides coded by the calcitonin gene family. All of them specifically reflect the ways and the pattern of alternative splicing of the primary transcript of the Calc I gene. Such relations implicate further investigations concerning the relationship between calcitonin circulating levels, biosynthetic activity of C-cells and the expression of gene encoding for this hormone, in normal and neoplastic conditions.

We have recently identified in medullary thyroid carcinoma the existence of a second calcitonin messenger, generated by a splicing between the 3' coding region of exon 4 and exon 5 of Calc I gene. It differs from the first one in its 3' coding sequence and codes for a calcitonin precursor which generates the same N terminal peptide, calcitonin and a specific 21 amino acid carboxy terminal peptide differing from Katacalcin by its 8 last amino acids. We searched for the expression of this new messenger in normal human thyroid tissue by Northern and by polymerase chain reaction techniques. This second calcitonin messenger was expressed in 4/4 normal thyroids and 4/5 medullary thyroid carcinoma tissue samples. The expression of this second messenger is apparently a common occurrence in C cells whether normal or tumoral.

Medullary thyroid cancer (MTC) is either of the sporadic or familial type, whether it be isolated or constitute part of a type II multiple endocrine neoplasia. Progress in the knowledge of the disease has recently been obtained in the following ways: the IRMA assay of mature calcitonin, the disease marker, has permitted earlier diagnosis of familial cases and recurrence; the locus assignment of the gene on chromosome 10 now enables a valid discrimination in certain families of gene carriers; collaborative clinical, biological, pathological, therapeutic and epidemiological research on a nation-wide scale has had a beneficial effect on patients, with improvement in diagnosis of the familial forms, in disease prognosis, in cancer detection at an infraclinical stage, and in the regrouping and distribution of families in France.

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.

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.

Carcinoembryonic antigen (CEA) and calcitonin (CT) were extracted from medullary carcinoma of the thyroid (MCT) tissues, fractionated on Sephacryl S-200 and chromatographed on Concanavalin A. CEA purified from MCT is closely related to CEA extracted from colonic tumors. It has an equivalent molecular weight, is a glycoprotein and has a similar electrophoretic mobility in both SDS and basic polyacrylamide electrophoresis. A certain degree of heterogeneity is present in the form of a smaller molecular weight component. Large molecular forms of CT which are present in MCT tissues and which co-elute with the minor component of CEA on Sephacryl chromatography can be separated by Concanavalin A chromatography.

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.

Plasma from patients with medullary carcinoma containing very high levels of immunoreactive calcitonin were fractionated by filtration on Sephadex gel. In all cases the elution gave four immunoreactive fractions. Two of these fractions correspond to the volume of elution of the monomere and of the dimere of human calcitonin. The two other fractions emerge at an elution volume corresponding to much higher molecular weights. After stimulation of calcitonin secretion in vivo, by dynamic tests, the fractions corresponding to the monomere and dimere increase more strongly than the two other fractions. Preliminary studies of secretion, in vitro, of calcitonin by medullary carcinoma tissue, show the presence in the incubate of four immunoreactive forms having the same elution characteristics as those found in the plasma. The significance of these results is discussed.

We have recently studied a kindred in which there have been 2 proven and 2 probable cases of medullary thyroid carcinoma without pheochromocytoma, hyperparathyroidism or Cushing's disease. Four other members suffered from intestinal occlusion and death occurred in three of them. The family has been traced through 4 generations (80 members) and 47 members could be examined; circulating calcitonin and carcinoembryonic antigen levels were measured. This study leads to two conclusions: 1) Medullary thyroid carcinoma is transmitted as an autosomal dominant trait with a high degree of penetrance. 2) Carcinoembryonic antigen is a valuable tumour marker particularly if no calcitonin radioimmunoassay is avialable for the diagnosis of M.C.T.

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.

We have recently studied a large family of 80 persons in which 47 were examined. The evaluation included history, blood pressure determination, palpation of the thyroid gland and determination of serum carcino-embryonic antigen (C.E.A.) and calcitonin (C.T.). Two members of the kindred had a proven M.C.T. without pheochromocytoma, hyperparathyroidism or Cushing's disease and two others a probable M.C.T. Four members suffered from intestinal occlusion and death occurred in three of them. Our conclusions are: 1) In this family traced through 4 generations: it appears that M.C.T. is transmitted as an autosomal dominant trait with a high degree of penetrance; 2) Our cases associated with those reported in the literature in the past few years point to the existence of a rare but distinct syndrome characterised by the association of M.C.T. and congenital megacolon with hyperplasia of the myenteric plexus; 3) As far as we know, this is the first indication of C.E.A. coupled with elevated calcitonin among several individuals of the same family. We confirm here the conclusions of previous studies: "C.E.A. is a valuable tumour marker which can be used for the detection of M.C.T., particularly if no calcitonin radio-immuno assay is available.