Stereotactic magnetic resonance imaging-guided radiotherapy for intracardiac metastases: A case report.

Adrenocortical carcinoma is a malignant tumor with a poor prognosis and a frequent metastatic extension. In very rare cases, a cardiac metastatic disease may occur, and surgical resection is essential for its management. MR-guided stereotactic radiotherapy is an attractive radiotherapy modality for the treatment of mobile thoracic tumors, enabling the target to be monitored continuously during irradiation, while the dosimetric plan can be adapted daily if necessary. We report here the case of a patient with intracardiac metastasis secondary to malignant adrenocortical carcinoma, treated with magnetic resonance imaging-guided stereotactic radiotherapy.

Pediatric pheochromocytoma in association with Von Hippel-Lindau disease: Focus on screening strategies.

INTRODUCTION: Von Hippel-Lindau disease (VHL) is a syndrome of familial predisposition to the development of malignant and benign tumours, due to mutations in the VHL tumour suppressor gene. Pheochromocytoma is a tumour that develops in the adrenal gland, rare in pediatric age, and may be associated with genetic abnormalities including mutations in the VHL gene. Systematic screening of pheochromocytoma in children carrying a VHL mutation has been proposed. However, some VHL patients who have been screened may develop symptoms associated with pheochromocytoma despite screening. Here, we report on such a case. CLINICAL CASE: A 13-year-old boy, known to be a carrier of a mutation of the VHL gene, undergoing annual screening, was admitted to our hospital for clinical symptoms related to a right adrenal pheochromocytoma discovered on abdominal imaging. After hemodynamic stabilisation, the pheochromocytoma was surgically resected. Histology confirmed the diagnosis of pheochromocytoma. The postoperative care was simple. The event-free period is currently 2 years. DISCUSSION: The present case has led us to reflect on the French and international screening strategies for pheochromocytoma in children carrying a mutation of the VHL gene. Between 2013 and 2018, six different recommendations were proposed for pheochromocytoma screening in secondary prevention for children with a VHL mutation, with variability regarding the age of onset and complementary examinations to be carried out. Despite the existence of these recommendations, our case demonstrates that a pheochromocytoma can develop by escaping well-performed screening. The role of early abdominal imaging should be redefined to improve the efficiency of screening. CONCLUSION: The discovery of a pheochromocytoma in a child must be systematically investigated for an underlying genetic cause. In the particular case of children carrying a mutation of the VHL gene, annual abdominal imaging should be included in the pheochromocytoma screening protocol from the age of 5 years.

TREATMENT OF CUSHING'S SYNDROME : WHAT PLACE FOR MEDICAL TREATMENT?

Surgery plays a major role as a first-line treatment of the different etiologies of Cushing's syndrome (CS) and bilateral adrenalectomy (BA) is extremely effective as a second line, so that there seems to be little room for medical treatment (MT). However, during the past years several drugs acting either on ACTH secretion or cortisol synthesis have been developed, so that MT of CS might be reassessed. After briefly analyzing the efficiency and tolerance of surgical and medical treatments of CS we try to distinguish consensual and controversial indications for MT. We believe the former include "pre-operative treatment" in rare patients in whom the severity of CS is likely to increase the risks of surgery; "inoperability" for rare patients who cannot be operated even when CS is controlled and "surgical failure or recurrence", mainly in patients Cushing's disease (CD) not in remission after TSS. Controversial indications include "unavailability of an expert surgeon", which we believe does not make sense when the cost of MT is taken into consideration. Finally in patients with the "surgical failure or recurrence" indication the balance between efficacy and side effects of MT should be balanced with the efficacy and side effects of BA.

French Endocrine Society Guidance on endocrine side effects of immunotherapy.

The management of cancer patients has changed due to the considerably more frequent use of immune checkpoint inhibitors (ICPIs). However, the use of ICPI has a risk of side effects, particularly endocrine toxicity. Since the indications for ICPI are constantly expanding due to their efficacy, it is important that endocrinologists and oncologists know how to look for this type of toxicity and how to treat it when it arises. In view of this, the French Endocrine Society initiated the formulation of a consensus document on ICPI-related endocrine toxicity. In this paper, we will introduce data on the general pathophysiology of endocrine toxicity, and we will then outline expert opinion focusing primarily on methods for screening, management and monitoring for endocrine side effects in patients treated by ICPI. We will then look in turn at endocrinopathies that are induced by ICPI including dysthyroidism, hypophysitis, primary adrenal insufficiency and fulminant diabetes. In each chapter, expert opinion will be given on the diagnosis, management and monitoring for each complication. These expert opinions will also discuss the methodology for categorizing these side effects in oncology using 'common terminology criteria for adverse events' (CTCAE) and the difficulties in applying this to endocrine side effects in the case of these anti-cancer therapies. This is shown in particular by certain recommendations that are used for other side effects (high-dose corticosteroids, contraindicated in ICPI for example) and that cannot be considered as appropriate in the management of endocrine toxicity, as it usually does not require ICPI withdrawal or high-dose glucocorticoid intake.

Expert opinions on adrenal complications in immunotherapy.

Primary adrenal insufficiency during immunotherapy is rare and does not warrant systematic screening during treatment. It should be suspected in case of typical clinical and biological presentation, but also in case of subclinical presentation with impaired general health status and/or hyponatremia. Diagnosis is based on low cortisol levels, measured at any time in case of emergency or else at 8 am, associated to elevated ACTH to rule out pituitary origin. Secondarily, anti-21-hydroxylase antibody assay may be performed, with screening for mineralocorticoid deficiency. Imaging is recommended, although not urgent, to screen for "adrenalitis" or adrenal atrophy and rule out differential diagnosis of adrenal metastasis. Primary adrenal insufficiency during immunotherapy is a medical emergency requiring hydrocortisone replacement adapted to the clinical and biological context. Management by an endocrinologist is essential, in order to adapt hydrocortisone and fludrocortisone replacement therapy and to educate both patient and oncologist in hydrocortisone dose adaptation. Current data suggest that treatment needs to be life-long, even after termination of immunotherapy. The present article does not deal with secondary adrenal insufficiency, which is included in the section on "Pituitary toxicity".

Histologically Proven Bronchial Neuroendocrine Tumors in MEN1: A GTE 51-Case Cohort Study.

OBJECTIVE: To evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death. br-NETs frequency ranges from 3 to 13% and may reach 32% depending on the number of patients evaluated and on the criteria required for diagnosis. METHODS: The 1023-patient series of symptomatic MEN1 patients followed up in a median of 48.7 [35.5-59.6] years by the Groupe d'étude des Tumeurs Endocrines was analyzed using time-to-event techniques. RESULTS: br-NETs were found in 51 patients (4.8%, [95% CI 3.6-6.2%]) and were discovered by imaging in 86% of cases (CT scan, Octreoscan, Chest X-ray, MRI). Median age at diagnosis was 45 years [28-66]. Histological examination showed 27 (53%) typical carcinoids (TC), 16 (31%) atypical carcinoids (AC), 2 (4%) large cell neuroendocrine carcinomas (LCNEC), 3(6%) small cell neuroendocrine carcinomas (SCLC), 3(6%) TC associated with AC. Overall survival was not different from the rest of the cohort (HR 0.29, [95% CI 0.02-5.14]). AC tended to have a worse prognosis than TC (p = 0.08). Seven deaths were directly related to br-NETs (three AC, three SCLC and one LCNEC). Patients who underwent surgery survived longer (p = 10-4) and were metastasis free, while 8 of 14 non-operated patients were metastatic. There were no operative deaths. CONCLUSIONS: Around 5% of MEN1 patients develop br-NETs. br-NETs do not decrease overall survival in MEN1 patients, but poorly differentiated and aggressive br-NETs can cause death. br-NETs must be screened carefully. A biopsy is essential to operate on patients in time.

[Hyponatremic-hypertensive syndrome successfully treated by endovascular therapy: A case report]. / Syndrome hyponatrémie hypertension artérielle efficacement traité par angioplastie à propos d'un cas.

INTRODUCTION: Hyponatremic-hypertensive syndrome (HHS) is characterized by hypertension and hyponatremia. CASE PRESENTATION: We report a case of HHS in a 73-year-old woman, revealed by a hyponatremia leading to status epilepticus, without initial hypertension due to hypovolemia. She was successfully treated by endovascular therapy without any long-term supplementation or anti-hypertensive medication. CONCLUSION: Physiopathology hypothesis of HHS implicate pressure natriuresis, in this case, hypertension is not initially found and we discuss other hyponatremia mechanisms.

Cabergoline for Cushing's disease: a large retrospective multicenter study.

OBJECTIVE: The efficacy of cabergoline in Cushing's disease (CD) is controversial. The aim of this study was to assess the efficacy and tolerability of cabergoline in a large contemporary cohort of patients with CD. DESIGN: We conducted a retrospective multicenter study from thirteen French and Belgian university hospitals. METHODS: Sixty-two patients with CD received cabergoline monotherapy or add-on therapy. Symptom score, biological markers of hypercortisolism and adverse effects were recorded. RESULTS: Twenty-one (40%) of 53 patients who received cabergoline monotherapy had normal urinary free cortisol (UFC) values within 12 months (complete responders), and five of these patients developed corticotropic insufficiency. The fall in UFC was associated with significant reductions in midnight cortisol and plasma ACTH, and with clinical improvement. Compared to other patients, complete responders had similar median baseline UFC (2.0 vs 2.5xULN) and plasma prolactin concentrations but received lower doses of cabergoline (1.5 vs 3.5 mg/week, P < 0.05). During long-term treatment (>12 months), cabergoline was withdrawn in 28% of complete responders because of treatment escape or intolerance. Overall, sustained control of hypercortisolism was obtained in 23% of patients for 32.5 months (19-105). Nine patients on steroidogenesis inhibitors received cabergoline add-on therapy for 19 months (1-240). Hypercortisolism was controlled in 56% of these patients during the first year of treatment with cabergoline at 1.0 mg/week (0.5-3.5). CONCLUSIONS: About 20-25% of CD patients are good responders to cabergoline therapy allowing long-term control of hypercortisolism at relatively low dosages and with acceptable tolerability. No single parameter, including the baseline UFC and prolactin levels, predicted the response to cabergoline.

[Metastatic medullary thyroid carcinoma in a child with multiple endocrine neoplasia 2B. Efficiency of medium-term treatment with vandetanib without thyroid surgery]. / Carcinome médullaire de la thyroïde métastatique : efficacité à moyen terme d'un traitement par vandétanib sans chirurgie thyroïdienne chez un enfant porteur d'une néoplasie endocrinienne multiple de type 2B.

Medullary thyroid carcinoma (MTC) is a rare cancer during childhood. MTC is sporadic in approximately 80% of cases and hereditary in 20%. When hereditary, it can be associated with other endocrine neoplasias and/or typical nonendocrine diseases, thus configuring the multiple endocrine neoplasia (MEN) syndromes. Children with clinically obvious MTC belong to MEN 2A or 2B families, related to RET mutations. The standard treatment is total thyroidectomy and central neck dissection. However, treatment of advanced MTC has not yet been standardized, even if a new tyrosine kinase inhibitor specific to RET mutation has changed the outcome of such patients. Vandetanib plays a role in the treatment of children with metastatic, locally advanced and nonoperable MTC, with good tolerance. We report the 5-year treatment of an 11-year-old patient, with vandetanib and without thyroid surgery.

Prognostic factors in stage III-IV adrenocortical carcinomas (ACC): an European Network for the Study of Adrenal Tumor (ENSAT) study.

BACKGROUND: The clinical course of advanced adrenocortical carcinoma (ACC) is heterogeneous. Our study aimed primarily to refine and make headway in the prognostic stratification of advanced ACC. PATIENTS AND METHODS: Patients with advanced ENSAT ACC (stage III or stage IV) at diagnosis registered between 2000 and 2009 in the ENSAT database were enrolled. The primary end point was overall survival (OS). Parameters of potential prognostic relevance were selected. Univariate and multivariate analyses were carried out: model 1 'before surgery'; model 2 'post-surgery'. RESULTS: Four hundred and forty-four patients with advanced ENSAT ACC (stage III: 210; stage IV: 234) were analyzed. After a median follow-up of 55.2 months, the median OS was 24 months. A modified ENSAT (mENSAT) classification was validated: stage III (invasion of surrounding tissues/organs or the vena renalis/cava) and stage IVa, IVb, IVc (2, 3 or >3 metastatic organs, including N, respectively). Two- or 5-year OS was 73%, 46%, 26% and 15% or 50%, 15%, 14% and 2% for stages III, IVa, IVb and IVc, respectively. In the multivariate analysis, mENSAT stages (stages IVa, IVb, or IVc, respectively) were significantly correlated with OS (P < 0.0001), as well as additional parameters: age ≥ 50 years (P < 0.0001), tumor- or hormone-related symptoms (P = 0.01 and 0.03, respectively) in model 1 but also the R status (P = 0.001) and Grade (Weiss >6 and/or Ki67 ≥ 20%, P = 0.06) in model 2. CONCLUSION: The mENSAT classification and GRAS parameters (Grade, R status, Age and Symptoms) were found to best stratify the prognosis of patients with advanced ACC.

Unraveling the intrafamilial correlations and heritability of tumor types in MEN1: a Groupe d'étude des Tumeurs Endocrines study.

BACKGROUND: MEN1, which is secondary to the mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Most studies demonstrated the absence of direct genotype-phenotype correlations. The existence of a higher risk of death in the Groupe d'étude des Tumeurs Endocrines-cohort associated with a mutation in the JunD interacting domain suggests heterogeneity across families in disease expressivity. This study aims to assess the existence of modifying genetic factors by estimating the intrafamilial correlations and heritability of the six main tumor types in MEN1. METHODS: The study included 797 patients from 265 kindred and studied seven phenotypic criteria: parathyroid and pancreatic neuroendocrine tumors (NETs) and pituitary, adrenal, bronchial, and thymic (thNET) tumors and the presence of metastasis. Intrafamilial correlations and heritability estimates were calculated from family tree data using specific validated statistical analysis software. RESULTS: Intrafamilial correlations were significant and decreased along parental degrees distance for pituitary, adrenal and thNETs. The heritability of these three tumor types was consistently strong and significant with 64% (s.e.m.=0.13; P<0.001) for pituitary tumor, 65% (s.e.m.=0.21; P<0.001) for adrenal tumors, and 97% (s.e.m.=0.41; P=0.006) for thNETs. CONCLUSION: The present study shows the existence of modifying genetic factors for thymus, adrenal, and pituitary MEN1 tumor types. The identification of at-risk subgroups of individuals within cohorts is the first step toward personalization of care. Next generation sequencing on this subset of tumors will help identify the molecular basis of MEN1 variable genetic expressivity.

MEN1 disease occurring before 21 years old: a 160-patient cohort study from the Groupe d'étude des Tumeurs Endocrines.

CONTEXT: Multiple endocrine neoplasia Type-1 (MEN1) in young patients is only described by case reports. OBJECTIVE: To improve the knowledge of MEN1 natural history before 21 years old. METHODS: Obtain a description of the first symptoms occurring before 21 years old (clinical symptoms, biological or imaging abnormalities), surgical outcomes related to MEN1 Neuro Endocrine Tumors (NETs) occurring in a group of 160 patients extracted from the "Groupe d'étude des Tumeurs Endocrines" MEN1 cohort. RESULTS: The first symptoms were related to hyperparathyroidism in 122 cases (75%), pituitary adenoma in 55 cases (34%), nonsecreting pancreatic tumor (NSPT) in 14 cases (9%), insulinoma in 20 cases (12%), gastrinoma in three cases (2%), malignant adrenal tumors in 2 cases (1%), and malignant thymic-NET in one case (1%). Hyperparathyrodism was the first lesion in 90 cases (56%). The first symptoms occurred before 10 years old in 22 cases (14%) and before 5 years old in five cases (3%). Surgery was performed before age 21 in 66 patients (41%) with a total of 74 operations: pituitary adenoma (n = 9, 16%), hyperparathyroidism (n = 38, 31%), gastrinoma (n = 1, 33%), NSPT (n = 5, 36%), and all cases of insulinoma, adrenal tumors, and thymic-NET. One patient died before age 21 due to a thymic-NET. Overall, lesions were malignant in four cases. CONCLUSIONS: Various MEN1 lesions occurred frequently before 21 years old, but mainly after 10 years of age. Rare, aggressive tumors may develop at any age. Hyperparathyroidism was the most frequently encountered lesion but was not always the first biological or clinical abnormality to appear during the course of MEN1.

Patients lost to follow-up in acromegaly: results of the ACROSPECT study.

OBJECTIVE: The complex management of acromegaly has transformed this disease into a chronic condition, with the risk of patients being lost to follow-up. The objective of this study was to estimate the proportion of acromegalic patients lost to follow-up in France and to determine the impact that abandoning follow-up has on the disease and its management. DESIGN: ACROSPECT was a French national, multicentre, cross-sectional, observational study. METHODS: Acromegalic patients were considered lost to follow-up if no new information had been entered in their hospital records during the previous 2 years. They were traced where possible, and data were collected by means of a recall visit or questionnaire. RESULTS: In the study population, 21% of the 2392 acromegalic patients initially followed in 25 tertiary endocrinology centres were lost to follow-up. At their last follow-up visit, 30% were uncontrolled, 33% were receiving medical therapy and 53% had residual tumour. Of the 362 traced, 62 had died and 77% were receiving follow-up elsewhere; the leading reason for abandoning follow-up was that they had not been informed that it was necessary. Our analysis of the questionnaires suggests that they were not receiving optimal follow-up. CONCLUSIONS: This study underlines the need to better inform acromegalic patients of the need for long-term follow-up, the absence of which could be detrimental to patients' health, and to develop shared care for what must now be regarded as a chronic disease.

Serum miR-483-5p and miR-195 are predictive of recurrence risk in adrenocortical cancer patients.

Adrenocortical carcinoma (ACC) is a rare cancer with poor prognosis. Local and distant recurrences occur in a subset of tumors classified as 'aggressive' ACC (aACC), as opposed to 'non-aggressive' ACC (naACC). In this study, we investigated whether tissue and serum microRNAs (miRNAs) are predictive of ACC prognosis. Tissue miRNA expression profiles were determined using microarrays in a test series of six adrenocortical adenomas (ACAs), six naACCs, and six aACCs. Eight miRNAs were selected for further validation by quantitative RT-PCR (ten ACAs, nine naACCs, nine aACCs, and three normal adrenals). Serum levels of five miRNAs were measured in samples from 56 subjects (19 healthy controls (HC), 14 ACA, nine naACC, and 14 aACC patients). MiR-195 and miR-335 levels were significantly decreased in both tumor and serum samples of ACC patients relative to ACA patients or HC. MiR-139-5p and miR-376a levels were significantly increased in aACC compared with naACC patients in tumor samples only. Tissue miR-483-5p was markedly upregulated in a majority of ACC compared with ACA patients or HC, but most importantly, serum miR-483-5p was detected only in aACC patients. High circulating levels of miR-483-5p or low circulating levels of miR-195 were associated with both shorter recurrence-free survival (P=0.0004 and P=0.0014 respectively) and shorter overall survival (P=0.0005 and P=0.0086 respectively). In conclusion, this study reports for the first time that circulating miR-483-5p and miR-195 are promising noninvasive biomarkers with a highly specific prognostic value for the clinical outcome of ACC patients.

A new prognostic clinicopathological classification of pituitary adenomas: a multicentric case-control study of 410 patients with 8 years post-operative follow-up.

Pituitary adenomas are currently classified by histological, immunocytochemical and numerous ultrastructural characteristics lacking unequivocal prognostic correlations. We investigated the prognostic value of a new clinicopathological classification with grades based on invasion and proliferation. This retrospective multicentric case-control study comprised 410 patients who had surgery for a pituitary tumour with long-term follow-up. Using pituitary magnetic resonance imaging for diagnosis of cavernous or sphenoid sinus invasion, immunocytochemistry, markers of the cell cycle (Ki-67, mitoses) and p53, tumours were classified according to size (micro, macro and giant), type (PRL, GH, FSH/LH, ACTH and TSH) and grade (grade 1a: non-invasive, 1b: non-invasive and proliferative, 2a: invasive, 2b: invasive and proliferative, and 3: metastatic). The association between patient status at 8-year follow-up and age, sex, and classification was evaluated by two multivariate analyses assessing disease- or recurrence/progression-free status. At 8 years after surgery, 195 patients were disease-free (controls) and 215 patients were not (cases). In 125 of the cases the tumours had recurred or progressed. Analyses of disease-free and recurrence/progression-free status revealed the significant prognostic value (p < 0.001; p < 0.05) of age, tumour type, and grade across all tumour types and for each tumour type. Invasive and proliferative tumours (grade 2b) had a poor prognosis with an increased probability of tumour persistence or progression of 25- or 12-fold, respectively, as compared to non-invasive tumours (grade 1a). This new, easy to use clinicopathological classification of pituitary endocrine tumours has demonstrated its prognostic worth by strongly predicting the probability of post-operative complete remission or tumour progression and so could help clinicians choose the best post-operative therapy.

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.

[Therapeutic innovation in osteoporosis (antisclerostin antibody and denosumab)]. / Innovations thérapeutiques dans l'ostéoporose (anticorps antisclérostine et denosumab).

Prevalence of osteoporosis, a systemic disease characterized by an impairment of bone mass, will continue to increase due to an ageing population and result in greater risks of fractures with disastrous medical and socioeconomic consequences. A better understanding of the regulation pathway of bone remodeling has led to the identification of new therapeutic targets. Denosumab, a monoclonal antibody against Receptor Activator of Nuclear factor κB-ligand (key molecule in osteoclastogenesis) is a fast-working, reversible antiresorptive treatment. A subcutaneous injection is required twice a year, a significant advantage over bisphosphonates whose efficiency is limited by an inadequate long-term compliance. The only anabolic agent currently available, Teriparatide (parathyroid hormone residues 1-34), administered daily via subcutaneous injection, stimulates both sides of bone remodeling in favour of bone formation. Anti-sclerostin antibodies neutralize an inhibitor of Wnt pathway, the master switch for osteoblastic differentiation, and meet the challenge of pioneering an anabolic drug that does not increase bone resorption. If the tolerance of these promising treatments is good in clinical trials of short duration, their implication in signaling pathways affecting various tissues means that one has to keep a very close watch on their long-term potential risks. Finally, the endocrinologists must be aware that the local regulating factors of bone remodeling recently identified (sclerostin, osteoprotegerin) seem to be the key mediators of hormones with bone tropism.

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.