Effects of gas adsorption on monolayer Si2BN and implications for sensing applications

Using density functional theory, we investigate the adsorption behavior of CO, NH3, and NO molecules on monolayer Si2BN. The energetically favorable structural configurations along with their adsorption energies, charge transfers, and electronic properties are discussed. The CO and NH3molecules show physisorption with moderate adsorption energies, whereas the NO molecule is subject to chemisorption. We further calculate the current-voltage characteristics using the non-equilibrium Green's function formalism. Significant anisotropy is observed for the armchair and zigzag directions, consistent with the anisotropy of the electronic band structure. Pronounced enhancement of the resistivity upon gas adsorption indicates that monolayer Si2BN is promising as gas sensing material.

Geographical variability of environmental parameters versus GPS precision: toward a better sampling strategy

To characterize a sedimentary environment, it is risky to take a single sample when the spatial variability is unknown. A reference station has to reflect the natural variations in order to allow the creation of long time series. However, it can remain unclear whether the temporal changes are real or due to a spatial variation. We highlight here the importance of spatial variability at the scale of precision of the GNSS. It appears that the number and arrangement of replicates depend on the environment and the studied parameters. InC, TOC and TS show a sufficiently low spatial variability to allow temporal tracking using GNSS without multiplying samples. The fine fraction percent shows a high spatial variability over small distances. The study of this parameter in the framework of temporal tracking requires a knowledge of its spatial variability during each period of sampling, and hence leads to the multiplication of samples.

Adrenal involvement in MEN1. Analysis of 715 cases from the Groupe d'etude des Tumeurs Endocrines database

OBJECTIVE

Limited data regarding adrenal involvement in multiple endocrine neoplasia type 1 (MEN1) is available. We describe the characteristics of MEN1-associated adrenal lesions in a large cohort to provide a rationale for their management.

METHODS

Analysis of records from 715 MEN1 patients from a multicentre database between 1956 and 2008. Adrenal lesions were compared with those from a multicentre cohort of 144 patients with adrenal sporadic incidentalomas.

RESULTS

Adrenal enlargement was reported in 20.4% (146/715) of patients. Adrenal tumours (>10 mm in size) accounted for 58.1% of these cases (10.1% of the whole patient cohort). Tumours were bilateral and >40 mm in size in 12.5 and 19.4% of cases respectively. Hormonal hypersecretion was restricted to patients with tumours and occurred in 15.3% of them. Compared with incidentalomas, MEN1-related tumours exhibited more cases of primary hyperaldosteronism, fewer pheochromocytomas and more adrenocortical carcinomas (ACCs; 13.8 vs 1.3%). Ten ACCs occurred in eight patients. Interestingly, ACCs occurred after several years of follow-up of small adrenal tumours in two of the eight affected patients. Nine of the ten ACCs were classified as stage I or II according to the European Network for the Study of Adrenal Tumors. No evident genotype/phenotype correlation was found for the occurrence of adrenal lesions, endocrine hypersecretion or ACC.

CONCLUSIONS

Adrenal pathology in MEN1 differs from that observed in sporadic incidentalomas. In the absence of relevant symptoms, endocrine biology can be restricted to patients with adrenal tumours and should focus on steroid secretion including the aldosterone-renin system. MEN1 is a high-risk condition for the occurrence of ACCs. It should be considered regardless of the size of the tumour.

Gender-related differences in MEN1 lesion occurrence and diagnosis: a cohort study of 734 cases from the Groupe d'etude des Tumeurs Endocrines

CONTEXT

Multiple endocrine neoplasia type 1 (MEN1) disease is an autosomal dominant syndrome that is believed to equally affect men and women. This assumption has never been confirmed.

OBJECTIVE

The aims of this study were to evaluate the impact of gender on the prevalence of MEN1 lesions, on their lifetime probability of occurrence, and on the diagnosis of MEN1.

DESIGN

Data regarding a study of 734 cases of MEN1 from the multicenter 'Groupe d'étude des Tumeurs Endocrines' were analyzed.

RESULTS

There were 57.8% females. The prevalence and probability of pancreatic tumors were higher in males than in females (P=0.06, P=0.0004). This difference was due to gastrinomas. The prevalence and probability of developing pituitary tumors were significantly greater in females (P<0.001, P<0.0001). Thymic tumors were exclusively found in men. There were no significant gender differences in the prevalence and the probability of developing hyperparathyroidism, or adrenal and bronchial tumors, or in the proportion of positive genetic tests. A family history of MEN1 was more frequently found in men than in women at the time of diagnosis (P=0.02). In the case of pituitary tumor, the proportion of patients diagnosed with MEN1 at the time of the first lesion was lower in women (44.2%) than in men (67.3%).

CONCLUSION

The phenotype expression of the MEN1 disease gene was different in males and females. In female patients, the possibility of MEN1 is not sufficiently taken into account. Any patient presenting a lesion that belongs to the MEN1 spectrum, such as a pituitary tumor, should be closely questioned about their family history and should be tested for hypercalcemia.

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.

The clinical variability of maternally inherited diabetes and deafness is associated with the degree of heteroplasmy in blood leukocytes

CONTEXT

Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes with a matrilineal transmission, sensorineural hearing loss, and macular pattern dystrophy due to an A to G transition at position 3243 of mitochondrial DNA (mtDNA) (m.3243A>G). The phenotypic heterogeneity of MIDD may be the consequence of different levels of mutated mtDNA among mitochondria in a given tissue.

OBJECTIVE

The aim of the present study was thus to ascertain the correlation between the severity of the phenotype in patients with MIDD and the level of heteroplasmy in the blood leukocytes.

PARTICIPANTS

The GEDIAM prospective multicenter register was initiated in 1995. Eighty-nine Europid patients from this register, with MIDD and the mtDNA 3243A>G mutation, were included. Patients with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) or with mitochondrial diabetes related to other mutations or to deletions of mtDNA were excluded.

RESULTS

A significant negative correlation was found between levels of heteroplasmy and age of the patients at the time of sampling for molecular analysis, age at the diagnosis of diabetes, and body mass index. After adjustment for age at sampling for molecular study and gender, the correlation between heteroplasmy levels and age at the diagnosis of diabetes was no more significant. The two other correlations remained significant. A significant positive correlation between levels of heteroplasmy and HbA(1c) was also found and remained significant after adjustment for age at molecular sampling and gender.

CONCLUSIONS

These results support the hypothesis that heteroplasmy levels are at least one of the determinants of the severity of the phenotype in MIDD.

Retinal and renal complications in patients with a mutation of mitochondrial DNA at position 3,243 (maternally inherited diabetes and deafness). A case-control study

AIMS/HYPOTHESIS

We assessed the prevalence and determinants of retinal and renal complications in patients with maternally inherited diabetes and deafness (MIDD).

METHODS

This was a multicentre prospective study comparing the prevalence of retinopathy and renal disease in 74 patients with MIDD and 134 control patients matched for sex, age and clinical presentation at onset of diabetes, duration of diabetes and current treatment. Comparisons were adjusted for HbA(1c) and hypertension.

RESULTS

In MIDD patients, HbA(1c) (7.6 +/- 1.6 vs 8.5 +/- 2.0%, p < 0.002), systolic blood pressure (126.6 +/- 16.2 vs 133.1 +/- 17.3 mmHg, p < 0.007) and prevalence of hypertension (33.8 vs 64.2%, p < 0.0001) were lower than in control patients. Prevalence of diabetic retinopathy was 3.7-fold lower in MIDD patients (6/74, 8 vs 40/134, 29.6%, p < 0.0001). Differences between groups remained significant after adjustment for hypertension, systolic blood pressure and HbA(1c). In MIDD, urinary albumin excretion (314.8 vs 80.1 mg/24 h, p = 0.035) and creatinine plasma levels (103.5 vs 82.2 micromol/l, p = 0.0178) were higher and GFR was lower. Impaired renal function (GFR <60 ml/min) was four- to sixfold more frequent in MIDD. Differences between MIDD and control diabetic patients further increased when adjusted for HbA(1c) and systolic blood pressure (p < 0.0001). Adjustment for treatment with an ACE inhibitor or angiotensin II receptor antagonist did not modify the results.

CONCLUSIONS/INTERPRETATION

This study indicates that diabetic retinopathy is less prevalent in MIDD than in control diabetes. This suggests that retinal alterations due to mitochondrial disease may have a protective role. By contrast, nephropathy is far more frequent in MIDD, suggesting the presence of a specific renal disease independent of diabetic nephropathy.

Hamartoma of the breast

Breast hamartoma is a rare benign tumour that leads to unilateral breast enlargement without a palpable localized mass lesion. Histologically, a hamartoma consists of varying amounts of adipose, gland, fibre and smooth muscle tissue. The characteristic mammographic appearance of hamartoma of breast has distinct mammographic features with circumscription and fat and soft-tissue density surrounded by a thin radiopaque capsule or pseudocapsule. Ultrasonographic findings include a well-defined mass lesion consisting of echogenic and sonolucent areas. We present histopathological and radiological findings of a 42-year-old female patient with breast hamartoma who has no complaint.

Observatoire francophone des néoplasies endocriniennes multiples de type 1. Un outil du Groupe d'étude des Tumeurs Endocrines (GTE)

Wermer's syndrome or Multiple Endocrine Neoplasia Type-1 (MEN1) is an autosomal dominant inherited disease, related to mutations in MEN1, an approximately 10-kb gene encoding menin, localized on chromosome 11q13. The Endocrine Tumor Group (GTE) has set up a MEN1 observatory of 1001 regularly followed MEN1 cases. This observatory aims at registering and evaluating MEN1 cases in a large cohort. Any new study on a particular unexplored aspect of the disease may be proposed by a physician to the GTE. This article describes the way to diagnose a new MEN1 case and to register it. Procedures for participating in a new study are presented. Some original results are quoted.

Clinical characterization of familial isolated pituitary adenomas

CONTEXT

Familial pituitary adenomas occur rarely in the absence of multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC).

OBJECTIVE

Our objective was to characterize the clinical and genealogical features of non-MEN1/CNC familial isolated pituitary adenomas (FIPA).

DESIGN AND SETTING

We conducted a retrospective study of clinical and genealogical characteristics of FIPA cases and performed a comparison with a sporadic population at 22 university hospitals in Belgium, Italy, France, and The Netherlands.

RESULTS

Sixty-four FIPA families including 138 affected individuals were identified [55 prolactinomas, 47 somatotropinomas, 28 nonsecreting adenomas (NS), and eight ACTH-secreting tumors]. Cases were MEN1/PRKAR1A-mutation negative. First-degree relationships predominated (75.6%) among affected individuals. A single tumor phenotype occurred in 30 families (homogeneous), and heterogeneous phenotypes occurred in 34 families. FIPA cases were younger at diagnosis than sporadic cases (P = 0.015); tumors were diagnosed earlier in the first vs. the second generation of multigenerational families. Macroadenomas were more frequent in heterogeneous vs. homogeneous FIPA families (P = 0.036). Prolactinomas from heterogeneous families were larger and had more frequent suprasellar extension (P = 0.004) than sporadic cases. Somatotropinomas occurred as isolated familial somatotropinoma cases and within heterogeneous FIPA families; isolated familial somatotropinoma cases represented 18% of FIPA cases and were younger at diagnosis than patients with sporadic somatotropinomas. Familial NS cases were younger at diagnosis (P = 0.03) and had more frequently invasive tumors (P = 0.024) than sporadic cases.

CONCLUSIONS

Homogeneous and heterogeneous expression of prolactinomas, somatotropinomas, NS, and Cushing's disease can occur within families in the absence of MEN1/CNC. FIPA and sporadic cases have differing clinical characteristics. FIPA may represent a novel endocrine neoplasia classification that requires further genetic characterization.

Bronchial atresia of the right lower lobe

Bronchial atresia (BA) is a rare congenital anomaly that is found incidentally in approximately 50% of cases. It predominantly affects young men and generally produces no symptoms. The other 50% of cases have pulmonary symptoms such as fever, cough, or shortness of breath due to recurrent pulmonary infection or overinflation of the involved lung parenchyma. The most common site is the left upper lobe, particularly of the apical-posterior segment. The right lower and middle lobes are affected in only 8% of cases. The radiographic features may be highly suggestive of the diagnosis. The mucus-filled bronchus is seen as a rounded, branching opacity emanating from the hilum and is surrounded by an area of increased hyper-translucency. We report an unusual presentation of BA in a 43-year-old woman with a history of recurrent pulmonary infection and dyspnea. The patient was found to have BA in all the basal segments of the lower lobe of the right lung.

High frequency of bone/bone marrow involvement in advanced medullary thyroid cancer

High hematological toxicity has been observed with anti-carcinoembryonic antigen radioimmunotherapy (RIT) in medullary thyroid carcinoma (MTC), suggesting metastatic bone involvement (BI). This retrospective study evaluated the rate of BI in MTC patients enrolled in two phase-I/II RIT trials using anti-carcinoembryonic antigen x anti-diethylenetriamine pentaacetic acid bispecific antibodies and [(131)I]di-diethylenetriamine pentaacetic acid hapten. Thirty-five patients underwent bone scintigraphy, bone magnetic resonance imaging (MRI), and post-RIT immunoscintigraphy (IS). IS performed in MTC patients was compared with IS conducted in 12 metastatic colorectal carcinoma (CRC) patients. Quantitative analysis of bone uptake was performed in three MTC and three CRC patients. In the MTC group, bone scintigraphy detected BI in 56.6% of patients, MRI in 75.8%, and IS in 88.6%. BI was confirmed by undirected (random) bone marrow biopsy, by bone surgery, or by two positive imaging methods in 74.3% of the patients. Sensitivity per patient of bone scintigraphy, MRI, and IS were 72.7, 100, and 100%, respectively. In contrast, IS visualized BI in only 33.3% of CRC patients; bone uptake was lower in CRC than in MTC patients. Bone MRI combined with post-RIT IS disclosed a much higher BI rate in advanced MTC than previously reported in the literature.

[Gastrinomas in multiple endocrine neoplasia type-1. A 127-case cohort study from the endocrine tumor group (ETG)]

On July 2000, 127 gastrinomas (31.1%) were studied by the Endocrine Tumour Group (GTE) using a 408-patient cohort of Multiple Endocrine Neoplasia Type 1 patients. The aim of this study was to assess clinical, biological, surgical data as well as their trends over three periods (<1980-1980/1989->1990). A Zollinger-Ellison syndrome (SZE) was present in 96% of the cases. Mean age at the onset of the disease was 39.4 years. There were 55.9% of men. Synchronous liver metastasis was present in 7.1%. Taken independently, the positivity of the four main diagnosis tests decreased over the time. The diagnosis of oesophagitis increased (4.5-29.7%), as well as the size of the resected tumours (9.9-16.8 mm). There was an increase in the familial background diagnosis (73.1-80%), an increasing use of Octreoscan scintigraphy and transduodenal ultrasound with positive detection of metastasis and tumours in 81.3% and 92.3%, respectively after 1991. Patients were operated on less frequently (96-52.5%), less frequently from the pancreas (87.5-37.5%), and from the gastro-intestinal tract (70.8-30%). The relative percentage of major pancreatic resections increased (with at least removal of the duodenum and the pancreatic head) (10-26.7%). The operative mortality disappeared. Six out of the seven patients (85.7%) who benefited from major pancreatic resections normalized their gastrine level postoperatively versus 15% in less radical techniques. Overall 5 years survival was 90 +/- 4.4%. Survival increased after 1985 (85 +/- 4.8% versus 95 +/- 3.6, P = 0.1).

CONCLUSION

SZE in NEM1 were diagnosed at an earlier stage and were less frequently operated on. Nevertheless, the incidence of synchronous metastasis did not change significantly. Patients were mainly operated on for gastric emergencies and pancreatic tumours in order to prevent metastasis without mortality after 1991.

Re-expansion pulmonary edema

Re-expansion pulmonary edema (REPE) is an uncommon complication following re-expansion of the lung as treatment of conditions such as hemopneumothorax, large pleural effusion, and after lobectomy, pneumothorax, or even during single-lung ventilation. The majority of REPE complications are associated with treatment of spontaneous pneumothorax. The etiology of REPE remains speculative, although it is thought to be caused by increased pulmonary capillary permeability. Risk factors, including young age, a large pneumothorax, and long duration of collapse, may help predict the patients that might encounter this complication.

Heterogeneity of diabetes phenotype in patients with 3243 bp mutation of mitochondrial DNA (Maternally Inherited Diabetes and Deafness or MIDD)

OBJECTIVE

In patients with maternally inherited diabetes and deafness (MIDD), due to 3 243 A > G mutation of mitochondrial DNA (mtDNA), diabetes may present with variable phenotypes.

OBJECTIVE

To ascertain the existence of two distinct phenotypes, MIDD1 and MIDD2, in a series of patients with MIDD.

DESIGN

Multicenter prospective study.

PATIENTS

77 patients with diabetes and the mtDNA 3243 mutation and 139 control patients with type 1 (T1D) or type 2 (T2D) diabetes, matched according to initial presentation of diabetes, age at onset, sex, and duration of diabetes (24 T1D and 115 T2D, including 55 treated with insulin).

MEASUREMENTS

Anthropometric characteristics (height, body weight, body mass index [BMI], sex), family history of diabetes, and characteristics of diabetes (age at onset, treatment, hemoglobin A1c [HbA1c]), extrapancreatic manifestations.

RESULTS

In 13 cases (17%, MIDD1), diabetes presented as insulin-dependent from the onset, with ketoacidosis in 6 cases. In 64 cases (83%, MIDD2), diabetes resembled T2D, and was treated with diet in 12 cases, oral hypoglycemic agents in 21 cases, or insulin in 31 cases. Compared with patients with MIDD2, patients with MIDD1 were characterized by lower age at onset of first manifestation of MIDD (25.4 +/- 9.6 vs 33.7 +/- 13.2 Years, P<0.0005), lower body weight (49.1 +/- 7.4 vs 56.3 +/- 10.9 kg, P<0.0025), lower BMI (18.2 +/- 2.3 vs 20.9 +/- 3.6 kg/m2, P<0.0005), and higher HbA1c levels (9.5 +/- 2.0 vs 7.5 +/- 1.6%, P<0.0005). Frequency of family history of diabetes and of extrapancreatic manifestations was the same in both MIDD subtypes. No difference was found within the MIDD2 subtype when comparing patients treated with or without insulin. Compared with matched controls, patients with MIDD had a lower BMI (MIDD1/T1D 18.2 +/- 2.3 vs 24.0 +/- 3.6 kg/m2 and MIDD2/T2D 20.9 +/- 3.6 vs 30.2 +/- 5.9 kg/m2, P<0.0025). Lastly, male patients with MIDD had a shorter height than controls (MIDD1/T1D: 166.1 +/- 3.2 vs 177.3 +/- 6.6 cm and MIDD2/T2D: 168.4 +/- 7.2 vs 173.6 +/- 6.6 cm P<0.025).

CONCLUSIONS

These results confirm the existence of two different phenotypes in MIDD, MIDD1 and MIDD2, which may be related to the severity of the mitochondrial disease. The role of other genetic and/or environmental factors in the variable phenotype of MIDD remains to be elucidated.

[Multiple endocrine neoplasia type I or Werner syndrome. What is important to know about surgery of a rate disease]

Multiple endocrine neoplasia type 1 (MEN1) is a rare but misleading disease. The diagnosis is evocated when two main lesions are present (parathyroid, endocrine pancreas, pituary gland) but also when a family tree shows recurrent lesions. Other lesions must be taken into account (adrenal glands, neuroendocrine thymic or bronchic lesions, cutaneous lesions, lipomas, nervous central system tumors). Any surgical cure without knowing the MEN1 background leads to failure. Specific treatment of each lesion is reviewed. Genetic diagnosis is possible but the mutation is not found in all cases. Nevertheless, when the mutation is known in a family, a negative genetic test allows to exclude the disease. Prognosis is related to hepatic metastases and to thymic neuroendocrine tumors which are rare (2.1%) but aggressive. As a general rule, any apparently isolated endocrine lesion such hyperparathyroidism must prompt the surgeon to look for another endocrine lesion and to look for an abnormal family tree with recurent monoglandular or pluriglandular lesions.

Presacral solitary giant neurofibroma without neurofibromatosis type 1 presenting as pelvic mass--case report

A 35-year-old woman presented with a solitary neurofibroma in an unusual presacral location without neurofibromatosis manifesting as bilateral chronic sciatica for 2 years. She was initially considered as having a giant right ovarian mass, but was referred with a prediagnosis of solitary giant sacral nerve sheath tumor. The initial differential diagnosis was based on neuroimaging. A right-sided J incision with the extraperitoneal approach provided good exposure and handling of the tumor bed. Almost total excision without neurological deficit was possible. The histological diagnosis was neurofibroma. Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease are quite rare. Intrapelvic tumors are often diagnosed at a later stage. Neuroimaging is very helpful to delineate this unusual site and the extent of tumor development, and to determine the appropriate surgical intervention. A clear understanding of retroperitoneal anatomy is essential for safe removal of such tumors. Complete resection is preferred to prevent local recurrence and malignant transformation. Although root section is inevitable, neurological deficit is unlikely.

RET rearrangements in familial papillary thyroid carcinomas

Familial papillary thyroid carcinoma (FPTC) is an inherited tumor characterized by a more aggressive phenotype than that of its sporadic counterpart. Its mode of inheritance as well as its genetic and molecular bases are still poorly understood. On the contrary, genetic alterations in sporadic papillary thyroid carcinoma (PTC) are better characterized, the most common one involving the activation of the proto-oncogene RET through somatic rearrangements. In the present study, we investigated by interphase fluorescence in situ hybridization the presence of RET rearrangements in a series of 20 FPTC. We show that one FPTC and the adenoma from the same patient carry a RET rearrangement (type PTC1) and that this rearrangement is absent in the germline. Furthermore, we excluded a RET haplotype sharing in two brothers of the same family. These results show that RET rearrangements can indeed be found in FPTC and confirm that RET is not involved in the inherited predisposition to FPTC.

Complete surgical lymph node resection does not prevent authentic recurrences of medullary thyroid carcinoma

BACKGROUND

Medullary thyroid carcinoma is a rare tumour derived from the thyroid parafollicular calcitonin-secreting cells. Calcitonin is a very specific marker of this cancer that allows preoperative diagnosis. Serum calcitonin assay is particularly useful to define the postoperative state of patients (cured, apparently cured, not cured) and, because of its great sensitivity, it has a major place in the postoperative follow-up.

OBJECTIVE

To identify, among patients thyroidectomized for medullary thyroid carcinoma (MTC), the characteristics of authentic recurrent MTC [re-elevation of stimulated serum calcitonin (CT) level measured by a sensitive immunoradiometric assay, after postoperative normalization].

PATIENTS AND METHODS

We first collected, through the national registry of the French Calcitonin Tumour Study Group (GETC), patients who had undergone a total thyroidectomy with or without lymph node surgery and who were not cured at the last follow-up visit. Among 453 such patients included in the database, 15 patients met the criteria for authentic recurrence as defined in previous studies: they had been first considered as cured during the 6 months following the initial surgical procedure (basal and pentagastrin-stimulated serum calcitonin level <or= 10 ng/l) but had a secondary rerise of their pentagastrin-stimulated calcitonin level, over 10 ng/l. Eight of them even had an undetectable (< 2 ng/l) immediate postoperative CT, confirming the initial postoperative cure. The characteristics (age, nature of disease, stage at surgery and type of node dissection) of these 15 patients were studied.

RESULTS

According to the Tumour Node Metastasis classification, nine patients were T1 and, among them, five patients had had complete lymph node surgery without any evidence of nodal metastases (N0). The recurrence was 3.2 +/- 2.2 years (range: 0.7-7.5) after the initial surgery.

CONCLUSIONS

3.3% of patients not cured at the last visit had a recurrent MTC. This recurrence occurred whatever the stage, and even if the primary surgery for MTC was a priori complete. These results emphasize the need for a regular biochemical follow-up because recurrence may appear many years after the initial surgery.

Familial medullary thyroid carcinoma with noncysteine ret mutations: phenotype-genotype relationship in a large series of patients

Familial medullary thyroid carcinoma only is related to germline mutations in the protooncogene RET, mainly in exons 10, whereas noncysteine mutations (exons 13-15) are considered infrequent. We analyzed 148 patients from 47 familial medullary thyroid carcinoma only families, and we found noncysteine RET mutations in 59.5% of these families. Of the index cases with noncysteine mutations, 43.4% presented with a multinodular goiter and high basal calcitonin; they were older at diagnosis than those with mutation in exon 10 and had more multifocal medullary thyroid carcinoma, but no difference in size, bilaterality, presence of C cell hyperplasia, or nodal metastases was found. Gene carriers with noncysteine RET mutations had a lower incidence of medullary thyroid carcinoma (78.2% vs. 94.1%) than those with mutation in exon 10; 20.2% had C cell hyperplasia only, although thyroidectomized at an older age. In conclusion, familial medullary thyroid carcinoma with noncysteine RET mutations are not infrequent and are overrepresented in presumed sporadic medullary thyroid carcinoma, suggesting that RET analysis should routinely be extended to exons 13, 14, and 15. The phenotype is characterized by a late onset of the disease, suggesting a delayed appearance of C cell disease rather than a less aggressive form. In familial medullary thyroid carcinoma gene carriers, the optimal timing for thyroidectomy remains controversial. Based on these data, we propose that surgery should be performed before elevation of the basal calcitonin level, potentially as soon as the pentagastrin test becomes abnormal.

Hyperparathyroidism in multiple endocrine neoplasia type I: surgical trends and results of a 256-patient series from Groupe D'etude des Néoplasies Endocriniennes Multiples Study Group

The French and Belgian GENEM study group's multiple endocrine neoplasia type I (MEN-I) database was used to evaluate trends in clinical presentation, surgical treatment of primary hyperparathyroidism (pHPT) (n = 245), and prognostic factors for hypercalcemia correction among 256 MEN-I cases. The patients were retrieved through the GENEM network from various Belgian and French institutions with the help of genetics laboratories. Among the 245 pHPT patients (96%), 42% were men. The mean age at the time of diagnosis was 39.5 +/- 13.3 years. Trends were studied for three periods: before 1986, from 1986 to 1990, and thereafter. After 1990 MEN-I patients were more often diagnosed with isolated pHPT (8%, 11%, 28%, for the three periods, respectively; p = 0.002); it was seen more often in screened patients (31%, 28%, 53%; p = 0.001), more often among those in already known MEN-I families (64%, 45%, 72%; p = 0.005), and among those with lower preoperative calcemia (2.93, 2.87, 2.79 mmol/L; p = 0.001). The age at pHPT diagnosis remained constant throughout the study. The percentage of cervical explorations dropped during the entire study (87%, 87%, 53%; p < 0.0001). After 1985 the percentage of subtotal parathyroidectomies increased (25%, 59%, 51%; p = 0.0004). Pathology disclosed more hyperplasias (59%, 85%, 74%; p = 0.008). Postoperative hypercalcemia decreased (47%, 15%, 19%; p < 0.0001); and postoperative hypocalcemia increased nonsignificantly (5%, 15%, 15%; p = 0.1). Subtotal parathyroidectomy [odds ratio (OR) 13], no MEN-I family background (OR 3), and the most recent study period (> 1985) (OR 3) were significant predictive factors of hypercalcemia correction according to the multivariate analysis. This is the first multicentric study on the management of MEN-I-related pHPT. Immediate postoperative hHPT cure increased, but only 80% of the operated patients were cured after 1990. Fifteen percent were hypocalcemic. Because MEN-I-related hHPT cure remains difficult to achieve, we advocate that subtotal parathyroidectomies be performed in specialized centers.

Maternally inherited diabetes and deafness: a multicenter study

BACKGROUND

Maternally inherited diabetes and deafness (MIDD), which is seen in 0.5% to 2.8% of patients with type 2 diabetes mellitus, is related to a point mutation at position 3243 of mitochondrial (mt) DNA. Its clinical description is incomplete.

OBJECTIVE

To study the clinical presentation and complications of diabetes in patients with MIDD and to identify clinical characteristics that may help select diabetic patients for mtDNA mutation screening.

DESIGN

Multicenter prospective descriptive study.

SETTING

16 French departments of internal medicine, diabetes and metabolic diseases, or both.

PATIENTS

54 patients with type 2 diabetes mellitus and the mtDNA 3243 mutation.

MEASUREMENTS

Characteristics of diabetes, metabolic control (glycosylated hemoglobin level), complications of diabetes, and involvement of other organs.

RESULTS

On average, patients with MIDD were young at diabetes onset and presented with a normal or low body mass index. None were obese. Seventy-three percent of probands had a maternal family history of diabetes. Diabetes was non-insulin-dependent at onset in 87% of patients; however, 46% of patients had non-insulin-dependent disease at onset but progressed to insulin therapy after a mean duration of approximately 10 years. Neurosensory hearing loss was present in almost all patients. Eighty-six percent of patients who received an ophthalmologic examination had macular pattern dystrophy (a specific retinal lesion). Forty-three percent of patients had myopathy, 15% had cardiomyopathy, and 18% (9 of 51) had neuropsychiatric symptoms. Although the prevalence of diabetic retinopathy was 8% among patients who received an ophthalmologic examination, lower than expected after a mean 12-year duration of diabetes, prevalence of kidney disease was 28%. This suggests that a specific renal involvement was the result of mitochondrial disease.

CONCLUSIONS

Maternally inherited diabetes and deafness has a specific clinical profile that may help identify diabetic patients for mtDNA testing.

Calcineurin blockade prevents cardiac mitogen-activated protein kinase activation and hypertrophy in renovascular hypertension

Chronic stimulation of the renin-angiotensin system induces an elevation of blood pressure and the development of cardiac hypertrophy via the actions of its effector, angiotensin II. In cardiomyocytes, mitogen-activated protein kinases as well as protein kinase C isoforms have been shown to be important in the transduction of trophic signals. The Ca(2+)/calmodulin-dependent phosphatase calcineurin has also been suggested to play a role in cardiac growth. In the present report, we investigate possible cross-talks between calcineurin, protein kinase C, and mitogen-activated protein kinase pathways in controlling angiotensin II-induced hypertrophy. Angiotensin II-stimulated cardiomyocytes and mice with angiotensin II-dependent renovascular hypertension were treated with the calcineurin inhibitor cyclosporin A. Calcineurin, protein kinase C, and mitogen-activated protein kinase activations were determined. We show that cyclosporin A blocks angiotensin II-induced mitogen-activated protein kinase activation in cultured primary cardiomyocytes and in the heart of hypertensive mice. Cyclosporin A also inhibits specific protein kinase C isoforms. In vivo, cyclosporin A prevents the development of cardiac hypertrophy, and this effect appears to be independent of hemodynamic changes. These data suggest cross-talks between the calcineurin pathway, the protein kinase C, and the mitogen-activated protein kinase signaling cascades in transducing angiotensin II-mediated stimuli in cardiomyocytes and could provide the basis for an integrated model of cardiac hypertrophy.

Malignant melanoma in patients with multiple endocrine neoplasia type 1 and involvement of the MEN1 gene in sporadic melanoma

Multiple endocrine neoplasia type 1 (MEN 1) is a familial cancer syndrome associated primarily with endocrine tumors of the parathyroids, enteropancreas and anterior pituitary. However, tumors of mesenchymal origin such as angiofibroma and collagenoma of the skin have also been associated with the syndrome. This highlights the possibility of an association between MEN 1 and some other types of tumors. Here we report 7 cases of primary malignant melanoma occurring in 7 MEN 1 families, all patients exhibiting classic features of MEN 1. Based on these findings and the previous implication of multiple melanoma tumor suppressor(s) in 11q, including the MEN1 region, we have investigated the involvement of the MEN1 gene in melanoma tumorigenesis. Mutation analysis was performed on a panel of 39 sporadic metastatic melanomas, 13 melanoma cell lines and 20 melanoma families without CDKN2A or CDK4 germline mutations. In addition, 19 sporadic metastatic tumors were screened for loss of heterozygosity (LOH) in 11q13. LOH was detected in 6 tumors (32%), and in 4 of the tumors the pattern of LOH suggested that the deletion included the MEN1 gene locus. A novel somatic nonsense mutation in exon 7 (Q349X) was identified in 1 sporadic tumor which also showed loss of the wild-type allele. We conclude that the MEN1 gene plays a role in the tumorigenesis of a small subgroup of melanoma.

Prognostic and immunohistochemical validation of the capella classification of pancreatic neuroendocrine tumours: an analysis of 82 sporadic cases

AIMS

To study the clinical outcome of 82 cases of pancreatic neuroendocrine tumours classified according to the recent histological and prognostic classification of Capella.

METHODS AND RESULTS

Eighty-two surgical cases of pancreatic neuroendocrine tumours were examined histologically with immunohistochemical staining of paraffin sections using streptavidin-biotin complex and application of antibodies against chromogranin A and 10 hormonal peptides. Classification in four groups correlated with long follow-up and outcome of these cases. Histological examination showed 30 group I, four group II, 41 group III and seven group IV tumours. Twenty-one (70%) of group I tumours were insulinomas, whereas 25% of group III tumours were glucagonomas and 25% were unclassified. Most group IV tumours were unclassified, showing no immunohistochemical staining with any of the 10 hormonal peptides tested. Outcome was clearly correlated with tumour group. Among the 14 patients who died of the disease, four had group IV and 10 group III tumours. Thus, unclassified asymptomatic tumours without immunohistochemical staining had a poorer prognosis than asymptomatic tumours with staining.

CONCLUSION

This study validates the Capella classification as easy to apply and useful in predicting clinical outcome.

[Prognostic factors of survival without clinical recurrences in medullary thyroid carcinoma: apropos of 52 operated cases]

The aim of this retrospective study on 52 operated medullary thyroid carcinoma (MTC) was to assess clinical and biochemical factors influencing survival without clinical recidive. There were 52% of familial cases. Mean age was 44 years (3 to 78 years) with 58% of women. The diagnostic was made prostoperatively in 38% of case (nodular specimen), when it was strongly suspected for 50% of patients before intervention (familial context, and/or preoperative Calcitonin (CT) levels, and/or mutation). The medial survival rate was 54 month (3 to 360 month). The absence of postoperative negativation of the CT (between 1 to 3 month) was meeting in 43% of case. Twenty one patients (42%) had presented one or several clinical relapse. At the end of the study, five patients were died in a postoperative time-limit of 22 to 110 month. The different parameters studed were: the sex, the age, the tumoral stage, the familial cases, the tum-oral size, the calcitonin levels normalisation in the three month postoperatively, and the local nodes extent. The 5-year survival rate was 90%, and the 10-year survival was 80%. The familial cases had a better pronostic than the sporadic (no death in the familial group versus 80% of 5-year survival rate in the sporadic cases). In univariate analysis, the good survival-factors without clinical recidive were: the stage I or II (p < 0,0001), the female sex (p = 0,02), the tumoral size under 10 mm (p < 0,02), the postoperative negativation of CT levels (p < 0, 0002), and the absence of cervical node extent (p < 0,0005). In multivariate analysis, only the postoperative negativation of CT-levels was a good survival-factor without clinical relapse (p < 0, 001).

Early or prophylactic thyroidectomy in MEN 2/FMTC gene carriers: results in 71 thyroidectomized patients. The French Calcitonin Tumours Study Group (GETC)

BACKGROUND

Once genetic testing accurately identifies MEN 2 gene carriers, affected children are given the opportunity to undergo thyroidectomy at the earliest stages of the C-cell disease.

OBJECTIVE

To define reliable parameters by which to identify the best moment for thyroidectomy in patients who are carriers of the MEN 2 gene.

PATIENTS AND METHODS

Seventy-one MEN 2/FMTC gene carriers, collected through the national register of the French Calcitonin Tumours Study Group, were evaluated. All the patients included were younger than 20 years of age and underwent total thyroidectomy. Basal and pentagastrin-stimulated calcitonin were assayed using an immunoradiometric method (sensitivity less than 2pg/ml). Calcitonin measurement was evaluated on the basis of histopathological findings in surgical thyroid specimens.

RESULTS

We found C-cell hyperplasia or medullary thyroid carcinoma in all the 71 gene carriers - even for the youngest patients - and nodal metastases were present in four cases. Calcitonin measurement (basal or pentagastrin-stimulated) detected C-cell disease preoperatively in all patients. Six of the 71 patients were not surgically cured: one had nodal metastases, one had an advanced staged disease and four had an incomplete nodal dissection or had not undergone lymph node surgery.

CONCLUSIONS

Determination of calcitonin forms an integral part of the management of MEN 2 gene carriers. Thyroidectomy is undisputably indicated when basal calcitonin is abnormal. When basal calcitonin is undetectable, a pentagastrin-stimulated increase in calcitonin to more than 10 pg/ml indicates an early thyroidectomy to cure the patient.

[Outcome in cervical recurrences of papillary or follicular thyroid cancer]

The aim of this study was to evaluate the treatment and outcome of patients with local recurrence (LR) of differentiated thyroid carcinoma. This retrospective study concerned patients treated between 1974 and 1990 for papillary or follicular thyroid cancer. Our patients had at least one LR. LR diagnosed within 6 months after thyroidectomy and patients with increased serum thyroglobulin levels were excluded. Thirty one patients (80% female) aged 15 to 84 years had at least one LR. LR was diagnosed 7 to 200 months after thyroidectomy (mean 63.7). There were 25 papillary and 6 follicular cancers. There were 1.5 LR per patient (range 1-6). LR were treated by radioiodine in 21 cases and by surgery in 22 cases. Among the 22 surgically treated patients, 7 had nodal recurrences, 7 had nodes and tumor, 3 had only tumor, 1 had recurrence in the remnant thyroid. After a mean follow-up of 75.8 months, 11 patients had distant metastases, 11 had died from their thyroid carcinoma (7 after metastases). Three of the 7 patients with nodal recurrence died. In one third of cases, LR announced distant metastases. Node recurrence had a poor prognosis.

Radioimmunotherapy in medullary thyroid cancer using bispecific antibody and iodine 131-labeled bivalent hapten: preliminary results of a phase I/II clinical trial

The toxicity and therapeutic efficacy of escalating doses of anti-carcinoembryonic antigen x anti-N alpha-(diethylenetriamine-N,N,N',N''-tetraacetic acid)-In bispecific monoclonal antibody (F6-734) and iodine 131-labeled bivalent hapten were determined in a Phase I/II trial. A total of 26 patients with recurrences of medullary thyroid cancer documented by imaging and a rise in serum thyrocalcitonin were enrolled. Twenty to 50 mg of F6-734 and 40-100 mCi of 131I-hapten were injected 4 days apart. Quantitative scintigraphy was performed after the second injection for dosimetry estimations in eight cases. Clinical, biological, and morphological follow-up was carried out for 1 year after treatment. The mean percentage of injected activity per gram of tumor at the time of maximum uptake was 0.08% (range, 0.003-0.26%). The tumor biological half-life ranged from 3 to 95 days, and tumor doses ranged from 2.91 to 184 cGy/mCi. The estimated tumor-to-nontumor dose ratios were 43.8 x 53.4, 29.6 x 35.3, 10.9 x 13.6, and 8.4 x 10.0 for total body, red marrow, liver, and kidney, respectively. Grade III/IV hematological toxicity was observed in seven patients, most of them with bone metastases. Among the 17 evaluable patients, 4 pain reliefs, 5 minor tumor responses, and 4 biological responses with decrease of thyrocalcitonin were observed. Nine patients developed human anti-mouse antibody. Dose-limiting toxicity was hematological, and maximum tolerated activity was 48 mCi/m2 in this group of patients, most of whom had suspected bone marrow involvement. The therapeutic responses observed in patients mainly with a small tumor burden are encouraging for the performance of a Phase II trial with minimal residual disease.

Lipid profile in actinic keratosis and basal cell carcinoma

BACKGROUND

The lipid content of the skin and its changes are important in the pathogenesis of many disorders affecting the skin, particularly actinic keratosis (AK) and basal cell carcinoma (BCC).

METHODS

Cholesterol, phospholipid, triglyceride, and total lipid levels were studied in paired lesional (AK and BCC) and nonlesional intact skin of 13 patients with AK and 12 patients with BCC. Serum concentrations of the same lipid fractions studied in the skin were investigated in AK and BCC patients and in 11 healthy, age-matched controls.

RESULTS

Levels of all lipid fractions were increased in both AK and BCC skin. When AK and BCC skin were compared with each other, a significant increase in phospholipids (p < 0.02) and total lipids (p < 0.01) was found in BCC. Serum cholesterol (p < 0.001), phospholipid (p < 0.001), triglyceride (p < 0.05), and total lipid (p < 0.001) concentrations of AK patients were significantly higher than those of the control group. When BCC and controls were compared, a significant increase in phospholipids and total lipids (p < 0.001) was seen. Serum cholesterol in BCC patients was significantly lower (p < 0.001) and serum phospholipid levels were significantly higher (p < 0.05) than those in the AK group.

CONCLUSIONS

An increase in the metabolically active serum phospholipid fraction is reflected in elevated neoplastic tissue phospholipid. This produces altered proportions between lipid fractions in tumorous areas and may result in changes in the intact nature of the cellular membrane, spread, and malignant proliferation.

[Von Hippel-Lindau disease: recent genetic progress and patient management. Francophone Study Group of von Hippel-Lindau Disease (GEFVH)]

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder, predisposing to the development of central nervous system (CNS) and retinal hemangioblastomas, endolymphatic sac tumors, renal cell carcinoma and/or renal cysts, pheochromocytomas, pancreatic cysts and/or tumors. Incidence of the disease is 1/36,000. CNS hemangioblastomas and renal cell carcinoma are the main causes of death. The VHL gene, located on 3p25-26, is a tumor-suppressor gene which plays a major role in regulation of VEGF expression. Germline mutations of the VHL gene are identified in about 70-99% of the patients. Mutations associated with VHL type 2 (with pheochromocytoma) are mainly missense mutations with hot-spot at codon 167. Somatic mutations of the VHL gene are found in both sporadic central nervous system hemangioblastomas and sporadic renal cell carcinoma. For endocrinologists search for VHL disease (as for MEN) should be imperative in presence of a patient with pheochromocytoma and neuroendocrine pancreatic tumor.

Improvement of blood glucose control in Type 1 diabetic patients treated with lispro and multiple NPH injections

AIMS

To evaluate a multiple daily injections (MDI) regimen combining lispro with multiple NPH insulin injections in order to replace basal insulin optimally.

METHODS

Twenty-five C-peptide negative Type 1 patients already trained to MDI were randomized to lispro (lispro + NPH 5 min before breakfast and lunch, lispro before dinner, NPH at bedtime) or soluble insulin (20-30 min before each meal and NPH at bed-time) for 3 months before crossing over to the other regimen for another 3 months. The mean initial HbA1c level was 8.32+/-1.5%.

RESULTS

The variability of capillary blood glucose values was significantly lower with lispro (MAGE 0.75+/-0.36 g/l vs. 0.99+/-0.50, P<0.01; MODD 0.64+/-0.26 g/l vs. 0.80+/-0.40, P<0.05). There was a nonsignificant reduction in HbA1c with lispro: -0.40+/-0.86 vs. -0.08+/-0.71. Mean daily blood glucose levels were significantly lower with lispro (1.53+/-0.48 g/l vs. 1.82+/-0.57 g/l, P<0.05). The frequency of all hypoglycaemic episodes was the same with both regimens but the number of severe hypoglycaemic events was reduced with lispro, P = 0.048. At the end of the study, 75% of the patients chose the lispro associated with multiple NPH regimen for their own treatment. The total insulin doses was the same with both regimens but the proportion of NPH was higher with lispro (53% vs. 34%).

CONCLUSIONS

An MDI regimen using lispro combined with multiple NPH compared to a standard MDI regimen using soluble insulin reduced day-to-day blood glucose fluctuations, was generally preferred by patients and was associated with a reduced incidence of severe hypoglycaemia with no loss of overall control.

Predictive factors for node involvement in papillary thyroid carcinoma. Univariate and multivariate analyses

For patients with papillary thyroid carcinoma, lymph node involvement is a common complication, resulting in node dissection and its resulting morbidity. To determine means of limiting lymph node dissections, we attempted to define intra-operative criteria predictive of node metastasis and so identify the patients likely to benefit from this procedure. This retrospective study concerned 158 patients (118 female) treated between 1974 and 1996 for papillary thyroid carcinoma by total thyroidectomy associated with bilateral (central and lateral) (n = 119) or unilateral (n = 39) dissection. The following criteria were used to study the predictive value of node involvement: age, sex, tumour size, tumour site, uni- or multifocality, existence or not of a tumour capsule, existence or not of perithyroid involvement and presence or not of vascular invasion. 99 patients (63%) had node involvement. Four factors showed predictive value for node involvement in univariate analysis: vascular invasion (P = 0.02), male sex (P = 0.008), absence of a tumour capsule (P < 0.0001) and perithyroid involvement (P < 0.0001). Two factors were predictive in multivariate analysis: absence of a tumour capsule and perithyroid involvement. Our results enabled us to calculate the risk of node involvement for each patient as a function of the existence of a peritumoral capsule and/or perithyroid involvement and to determine the indication for dissection. When neither of these factors was present, the risk of node involvement was 38.3% and dissection was not considered essential. If both risk factors were found, the risk was 87.1% and dissection was considered necessary.

Prognostic factors in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. Groupe d'Etude des Néoplasies Endocriniennes Multiples (GENEM and groupe de Recherche et d'Etude du Syndrome de Zollinger-Ellison (GRESZE)

BACKGROUND & AIMS

Risk factors of metachronous liver metastases and death are not well known in patients with the Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. These factors were retrospectively determined in 77 patients.

METHODS

Data chart review was performed.

RESULTS

Median follow-up was 102 months (range, 12-366). Surgery was performed on 48 patients, including 9 of the 10 patients with large pancreatic tumors (>/=3 cm). Liver metastases developed in 4 patients (40%) with large pancreatic tumors, in 3 (4.8%) without, and in 1 of the 4 patients with pancreatic tumors of unknown size; all had previously undergone surgery. The only independent factor associated with development of liver metastases identified by multivariate analysis was large pancreatic tumors (risk ratio, 29.0; 95% confidence interval [CI], 3. 2-260.7). Surgery was not selected. The probability of being free of liver metastases in the 63 patients without large pancreatic tumors was 96% (95% CI, 88-100) at 10 and 15 years. Thirteen (16.9%) patients died. The only independent factors of death selected by multivariate analysis were Zollinger-Ellison syndrome diagnosis before 1980 (risk ratio, 8.2; 95% CI, 1.7-40.6) and age at diagnosis (risk ratio/year, 1.08; 95% CI, 1.03-1.14).

CONCLUSIONS

Large pancreatic tumors are predictive of the development of metachronous liver metastases, and surgery does not seem to prevent them.

Sporadic medullary microcarcinoma of the thyroid: a retrospective analysis of eighty cases

Clinical characteristics and prognosis of 80 patients (53 women and 27 men) with sporadic medullary thyroid carcinomas (MTC), less than 1 cm in size (micro-MTC), operated on between 1971 and 1996 are reported (73 total and 7 partial thyroidectomies). These patients, obtained from a national database of 899 patients with MTC, were compared with 357 cases of sporadic MTC greater than 1 cm and 149 subjects with familial MTC less than 1 cm (familial micro-MTC). Median age at surgery was 52.5 years, a distribution similar to larger sporadic MTC. Micro-MTC was identified due to elevated calcitonin (47.5%), clinically identified lymph node (10.0%), distant metastases (6.3%) or pathologic finding at surgery (36.2%). Diarrhea and/or flushing were observed in 6 patients including 4 with clinically identified lymph node. Among patients who had lymph node dissection at surgery (68.8%), lymph node involvement with tumor was observed in 30.9%, and was significantly more frequent in multifocal (7/11) than in unifocal micro-MTC (p < 0.03). All sporadic micro-MTC were unilateral. Survival rate was 93.9% +/- 4.4% (SE) at 10 years, greater than that observed in sporadic macro-MTC (p = 0.04). Normal postoperative basal calcitonin (CT) was obtained in 71.1% of micro-MTC patients versus 33.6% in sporadic macro-MTC (p < 0.01). Sporadic micro-MTC is much more frequent than expected, 15% of MTC in our series. Although specific survival rate and percentage of biological cure in micro-MTC are significantly better than for larger tumors, the frequency of lymph node involvement, however, justifies an aggressive surgical approach including total thyroidectomy and bilateral central lymph node dissection.

[Early therapeutic management of patients genetically predisposed to medullary thyroid cancer]

STUDY

The aim of our study was to study therapeutic results after thyroidectomy in patients positive for predictive genetic analysis and with preoperative calcitonin (CT) response to pentagastlin (Pg) < 150 pg/ml.

MATERIAL AND METHODS

36 patients (13 F, 23 M) were selected: 13 F-MTC from 8 families, 22 MEN 2A from 15 families and 1 MEN 2B. They were positive for direct RET mutation analysis. CT was assayed by immunoradiometric method before and after Pg. Pg test results before and after thyroidectomy, age at operation and histologic results were analysed.

RESULTS

Mean preoperative peak CT was 82.5 +/- 34.0 pg/ml (22-133): among these 36 patients preoperative basal and peak CT were normal in 16 and 2 patients respectively. F-MTC and MEN 2A patients were different according to their preoperative peak CT levels (58.1 +/- 24.0 vs 97.6 +/- 31.3) pg/ml, p < 0.01) and age at thyroidectomy (20.4 +/- 10.5 vs 11.6 +/- 7.6 years, p < 0.01 by Mann-Whitney test). Total thyroidectomy was performed in all patients at a mean age of 14.8 +/- 9.8 years (2.5-41.7) and was associated with lymph node dissection in 30 cases. The 2 F-MTC patients with normal preoperative peak CT levels had bilateral C-cell hyperplasia (CCH) associated with uni or bilateral micro-MTC. Other patients had uni or bilateral micro MTC except 4 who had isolated CCH without carcinoma. The age of two MEN-2A and 1 MEN 2B patients with micro-MTC ranged from 2.5 to 4.7 yr. Micro MTC was present in 100% of MEN-2A cases after the age of 10 yr. There were no lymph nodes metastases. During postoperative survey, the last PG tests (n = 33) were performed 27.5 months (1-92) after thyroidectomy: peak CT values were always < 10 pg/ml.

IN CONCLUSION

Thyroidectomy should be performed at a very young age in RET mutation carriers, regardless of the plasma CT values. This choice is justified in NEM-2A and NEM-2B patients but must be discussed in F-MTC families with less aggressive forms of the disease.

Germ-line mutation analysis in patients with multiple endocrine neoplasia type 1 and related disorders

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant syndrome predisposing to tumors of the parathyroid, endocrine pancreas, anterior pituitary, adrenal glands, and diffuse neuroendocrine tissues. The MEN1 gene has been assigned, by linkage analysis and loss of heterozygosity, to chromosome 11q13 and recently has been identified by positional cloning. In this study, a total of 84 families and/or isolated patients with either MEN1 or MEN1-related inherited endocrine tumors were screened for MEN1 germ-line mutations, by heteroduplex and sequence analysis of the MEN1 gene-coding region and untranslated exon 1. Germ-line MEN1 alterations were identified in 47/54 (87%) MEN1 families, in 9/11 (82%) isolated MEN1 patients, and in only 6/19 (31.5%) atypical MEN1-related inherited cases. We characterized 52 distinct mutations in a total of 62 MEN1 germ-line alterations. Thirty-five of the 52 mutations were frameshifts and nonsense mutations predicted to encode for a truncated MEN1 protein. We identified eight missense mutations and five in-frame deletions over the entire coding sequence. Six mutations were observed more than once in familial MEN1. Haplotype analysis in families with identical mutations indicate that these occurrences reflected mainly independent mutational events. No MEN1 germ-line mutations were found in 7/54 (13%) MEN1 families, in 2/11 (18%) isolated MEN1 cases, in 13/19 (68. 5%) MEN1-related cases, and in a kindred with familial isolated hyperparathyroidism. Two hundred twenty gene carriers (167 affected and 53 unaffected) were identified. No evidence of genotype-phenotype correlation was found. Age-related penetrance was estimated to be >95% at age >30 years. Our results add to the diversity of MEN1 germ-line mutations and provide new tools in genetic screening of MEN1 and clinically related cases.

[Thymic and bronchial neuroendocrine tumors in multiple endocrine neoplasia type 1. GENEM1]

OBJECTIVES

Multiple endocrine neoplasia type 1 (MEN 1) mainly affects parathyroid glands, pancreatic islets and pituitary gland. The aim of this study in 95 MEN 1 patients was to examine less frequent localizations thymic and bronchic neuroendocrine tumors (NET).

PATIENTS AND METHODS

Two cases of bronchic NET were observed, both in women, and 4 cases of thymic NET, all in men, giving a prevalence of 7.3%. These NET were often asymptomatic. A metastatic diffusion was observed in 3 cases. Elevated plasma levels of glycoprotein hormone alpha subunit (SU) and FSH were observed in 3 and 1 cases respectively. Immunohistochemistry indicated the tumor cells to be frequently positively stained for HCG alpha and FSH.

DISCUSSION

We conclude that all patients with MEN 1 should undergo screening for thoracic NET, especially in high risk familial subgroups and in case of elevated plasma alpha SU or FSH.

[Postpartum thyroiditis and Basedow disease]

BACKGROUND

The postpartum period is characterized by a rebound in autoimmunity secondary to immune tolerance induced by pregnancy, creating favorable conditions for flare up of Graves' disease or autoimmune thyroiditis. Postpartum thyroiditis is a recognized clinical entity.

CASE REPORT

Six years after onset of Graves' disease treated with antithyroid drugs, a 25-year-old woman had a high serum level of antithyroperoxidase antibodies a few months before she became pregnant. Six weeks after delivery, she developed signs of hyperthyroidism and goiter. The diagnosis of postpartum thyroiditis was retained. Her condition regressed spontaneously to euthyroidism then hypothyroidism.

DISCUSSION

The therapeutic options involved underline the importance of distinguishing between Graves' disease and postpartum thyroiditis. The diagnosis of postpartum thyroiditis is based on history taking, clinical findings, and laboratory tests, especially isotope uptake.

Management of patients and subjects at risk for multiple endocrine neoplasia type 1: MEN 1. GENEM 1. Groupe d'Etude des Néoplasies Endocriniennes Multiples de type 1

Multiple endocrine neoplasia type 1 (MEN 1) is characterized by the combined occurrence, to variable degree, of hyperparathyroidism (HPT) (85.7% of cases according to the French Registry of GENEM 1), tumors of the endocrine pancreas (49.6%), pituitary adenomas (38.4%) and, less frequently, adrenal tumors (9.6%) and neuroendocrine tumors (5.8%). Currently, diagnosis of MEN 1 is done in the fourth decade of life, but familial screening (using genetic tools whose diagnostic accuracy approaches 100%) has lowered the age of diagnosis. Screening for MEN 1 in a patient harboring an apparently sporadic tumor will depend on the endocrine gland involved. Extensive screening for MEN 1 in the presence of HPT will be conducted only when the familial history is suggestive, when parathyroid glands are hyperplastic or when multiple parathyroid adenomas have been found at surgery. All patients with an endocrine pancreas tumor need to be investigated for the presence of other endocrine lesions of MEN 1. Extensive screening for MEN 1 is only recommended when a patient with a pituitary tumor or an adrenal tumor has a familial history suggestive of MEN 1. Otherwise regular measurement of blood calcium and PTH levels seem sufficient. Extensive screening for endocrine lesions when MEN 1 is suspected involves hormone measurements and imaging procedures. For the diagnosis of HPT, calcemia and PTH 1-84 must be measured. In the absence of clinical symptoms, basal measurement of serum gastrin, glucose, insulin, glucagon, VIP, somatostatin and pancreatic polypeptide levels are combined with abdominal ultrasonography. When symptoms suggest the Zollinger-Ellison syndrome, the secretin stimulation test is recommended. The diagnosis of a pituitary tumor is made by pituitary imaging and selected hormone assays (mainly PRL). To detect an adrenal tumor, CT scan is recommended, combined with serum potassium, urinary free cortisol and androgen measurement. When the diagnosis of MEN 1 is made, clinical and hormonal follow-up (once a year) and imaging surveillance (every 3-5 years) may be sufficient to detect new other endocrinopathies (unless suggestive clinical symptoms arise). Surgical management of each endocrine lesion must be done by skilled surgeons according to therapeutic protocols which have been discussed in detail. Genetic screening is an integral part of familial screening which may be conducted in collateral and in the offspring of MEN 1 patients. Obviously ethical principles (informed consent, etc.) must be respected. As it is now possible to detect presymptomatic gene carriers with a high degree of accuracy, follow-up is needed to make appropriate management decisions. The marked anxiety provoked by screening in an overtly asymptomatic healthy subject must not be underestimated. Conversely, a negative genetic diagnosis helps to reassure the subject and avoid repetitive and costly follow-up.

Multiple endocrine neoplasia type 2: management of patients and subjects at risk. French Study Group on Calcitonin-Secreting Tumors (GETC)

Multiple endocrine neoplasia type 2 (MEN-2) is an inherited multiglandular disease with age-related penetrance and variable expression. The prognosis of MEN-2 is linked to the carcinological evolution of medullary thyroid cancer (MTC), which depends mainly on the stage of discovery, and to the incidents related to pheochromocytomas. The emphasizes the need for early diagnosis and management of MEN-2. Since 1993, mutations evidenced on the protooncogene RET have allowed subjects at risk to be identified, thus leading to a three-step management of these patients. (1) For all the potentially affected members of a MEN-2 family, screening by molecular genetics of the ret gene enables one to identify the subjects at risk who bear the mutation. When no mutation is observed, a linkage analysis study may be proposed. (2) In the subjects at risk, early screening for the various types of endocrine lesions may then start in childhood and be performed using specific biological markers of MTC, pheochromocytoma and primary hyperparathyroidism, and particularly, basal and pentagastrin-stimulated calcitonin measurement, which is known to be the most sensitive marker for the monitoring of MTC. (3) This step of biological investigations enables the earliest possible treatment of any endocrine lesion detected before it is expressed clinically, thus improving the prognosis of MEN-2. When genetic screening cannot be performed, only annual clinical and biological monitoring remain available in all members of a family affected with MEN-2.