[The thyrogastric syndrome: its effects on micronutriments and gastric tumorigenesis]

The thyrogastric autoimmune syndrome (TAS) was described in patients in whom the serum cross-reacted both with gastric parietal cells antigens and thyroid antigens. We report two cases illustrating the spectrum of pathogical features of TAS. The first case associates Hashimoto's thyroiditis and anemia perniciosa,and develops a gastric neuroendocrine tumor during follow up. The second case presents with a Graves' disease and an autoimmune reversible gastritis, secondary to Helicobacter pylori. Whereas type III autoimmune polyendocrinopathy is rare, TAS is frequent in our experience. Some 13% (32/240) of patients that we have prospectively followed affected with thyroiditis have also autoimmune gastritis. Helicobacter pylori is clearly implicated in 16% of autoimmune gastritis cases. Infection, malabsorption and gastritis are potentially reversible after bacterial eradication treatment. In the other 84% of gastritis patients, no histological or serological proof of Helicobacter pylori is found. Gastric autoimmunity is then irreversible, leading to gastric severe atrophy, hypochlorhydria and hypergastrinemia. Hypergastrinemia stimulates enterochromaffin cell hyperplasia, possibly progressing to neuroendocrine tumors. We propose a diagnostic approach to improve the characterization of TAS. We review the literature on the subject and discuss some interesting animal models of infectious gastric autoimmunity.

[Neonatal hyperthyroidism: clinical pattern and therapy]

Neonatal hyperthyroidism is a rare pathology, most often the consequence of Graves' disease in the mother. Around 0.2% of pregnant women have Graves disease and 1 to 2% of newborns of mother with Graves' disease. This article will describe the case of 4 newborns who have been diagnosed and treated in CHU-NDB between 2007 and 2011. The second part will focus on the new recommendations about the management of these young patients from foetal period to birth.

[Clinical case of the month. Anterior mediastinal mass in a patient with acromegaly]

The discovery of an anterior asymptomatic mediastinal mass with acromegaly creates a dilemma for the clinician. As acromegaly can be due to a pituitary tumor but also to an ectopic production of GHRH, the first diagnostic step consists of finding the etiology of the disease in order to use adequate treatment. This can be complicated by the fact that acromegaly can be associated with other tumors (for instance in MEN-1 disease and Carney Complex) and because chronic GH hypersecretion can stimulate tumor overgrowth and perhaps tumor formation. We describe the case of a 44-year-old acromegalic woman with an anterior mediastinal mass. We present the different diagnoses and a review of the literature.

The treatment of sporadic versus MEN1-related pituitary adenomas

The treatment of pituitary tumours strongly depends on their clinical presentation. In general, the treatment aims are reducing tumour volume and/or decreasing hormone hypersecretion. It relies on single or a combination of three different methods: surgery, medication and radiotherapy. The rationale for deciding the treatment are many but include the aggressiveness of the tumour. The aetiologies of sporadic pituitary adenomas are not fully understood. However, several causes have been identified resulting in specific familial phenotypes like multiple endocrine neoplasia type I (MEN1). MEN1 is related to mutations in the MEN1 gene, a tumour suppressor gene localized on chromosome 11q13 and which encodes menin, a 610 amino acid protein. During the last years, an evidence progressively emerged that MEN1-related adenomas were more aggressive and less responsive to therapy than their sporadic counterparts. In this article, we review the differences between sporadic and MEN1-related adenomas and suggest specific ways of treatment and follow-up for MEN1-related tumours.

The changing spectrum of TSH-secreting pituitary adenomas: diagnosis and management in 43 patients

OBJECTIVE

Our aim was to report the recent changes in diagnosis and management of TSH-secreting pituitary adenomas.

METHODS

We retrieved 43 consecutive patients with TSH-secreting pituitary tumors (23 male and 20 female) among 4400 pituitary adenomas followed between 1976 and 2001 in six Belgian and French centers.

RESULTS

TSH was elevated in 18/43 and alpha subunit in 13/32 patients. In patients with intact thyroid (n=30), mean free tri-iodothyronine was 13.1 pmol/l (range 3.5-23) and mean free thyroxine was 38.4 pmol/l (range 10.2-62.7). Hyperprolactinemia and acromegaly were associated in 9/43 and 8/43 cases. The number of associated hypersecretions was higher in macroadenomas than in microadenomas (Chi square = 11.2, P<0.01). Two women had sporadic multiple endocrine neoplasia type 1-associated syndrome. The proportion of microadenomas versus macroadenomas was 1/11 (period 1974-1986) and 8/32 (period 1987-2001). Bilateral petrosal sinus sampling, (111)In-pentreotide scintigraphy and ((11)C)-l-methionine positron emission tomography scan confirmed diagnosis in four questionable microadenomas. Macroadenomas with extrasellar extension (31 cases) had a tendency to be medially located. Medical treatment with somatostatin analogs was initiated as first-line treatment in 26 patients. TSH levels were reduced by more than 50% in 23/26 cases. A tumoral shrinkage of more than 20% was observed in 5/13 cases. Surgery was performed in 36 patients. After 1 year, 21 of them (58.3%) met the criteria of surgical favorable outcome. Pituitary radiotherapy (n=8) and somatostatin analogs allowed normalization in cases not cured by surgery.

CONCLUSION

Ultrasensitive methods for TSH measurement led to an earlier recognition of TSH-secreting pituitary tumors. In this series, we observed that TSH-secreting pituitary tumors are today more frequently found at the stage of microadenomas, medially located, without associated hypersecretions and needing new exploration methods as compared with older series. This changing spectrum in the presentation of TSH-secreting pituitary tumors and the excellent response to somatostatin analogs has been accompanied by an improvement in the prognosis of the disease.

[Acromegaly and pregnancy]

Acromegaly usually results from GH hypersecretion by a somatotroph adenoma. The fertility of acromegalic patients is often impaired. Several factors may impact the course of pregnancy in acromegaly. Disturbed pituitary function might lead to infertility or spontaneous abortion. GH is a powerful insulin antagonist, and pregnant acromegalic patients are prone to added glucose intolerance and diabetes. Pregnancy itself might also impact the course of the pituitary tumor. During pregnancy, the normal pituitary increases in size due to estrogens-mediated hyperplasia. Therefore, tumors are at risk for hemorrhage due to enhanced vascularity, and might compress the optic chiasm. In this article we summarize the data on the literature on the reciprocal influences between acromegaly and pregnancy, we discuss therapeutic options and advance diagnostic and surveillance schedules of acromegaly during pregnancy.

[Multihormonal bilateral petrosal sinus sampling in Cushing's disease: radiological, surgical and pathological correlations]

Multihormonal bilateral petrosal sinus sampling (BPSS) has been proposed to improve corticotroph microadenomas prediction of lateralisation. Few series have simultaneously compared data of pituitary MRI, surgical findings and multihormonal BPSS. Seven patients (6F/1M) with Cushing's disease, mean age at diagnosis of 35 years (range 24-55) were prospectively studied to compare radiological and multihormonal BPSS data with surgical and pathological findings. In untreated patients, simultaneous measures of ACTH, TSH and prolactine (PRL) were done at time 0, 7, 15, 22 minutes after CRH (500 microgram) and TRH (200 microgram) stimulation. An intersinus gradient of 1.4 was considered as a lateralisation. All microadenomas were identified during surgery, diameters ranged from 2 to 7 mm. All patients were in long-term surgical remission. Pathological studies confirmed a tumoral tissue with ACTH immunostaining in 6/7 cases and PRL in 3/7 cases. Pituitary MRI correctly identified tumors in 4 cases, the remaining tumors were not seen. Basal and stimulated intersinus gradients of ACTH, TSH and PRL were homolateral in 6/7 cases and were coincident with surgical findings in 4/7 cases. The other three cases were contralateral to MRI and surgical data. In conclusion, simultaneous gradient of ACTH, PRL and TSH did not improve lateralisation prediction in this series. Hormonal hypersecretion was homolateral in six cases whereas pathological studies demonstrated a mixed secretion in only three cases. A preferential pituitary draining could explain these discordances. Data from our series and from others (done with CRH stimulation and ACTH-PRL measures) strongly suggest a paracrine interaction between tumoral and normal pituitary tissue.

[Pituitary pathology and MEN 1]

Multiple Endocrine Neoplasia type 1 (MEN 1) is an autosomal dominant syndrome characterized by neoplasia of the parathyroid glands, the endocrine pancreas and the anterior pituitary gland. Recently the identification on chromosome 11 (locus q13) of the gene responsible for MEN 1 has allowed direct genetic diagnosis of MEN 1-affected family members. To date almost 300 families have been described and genetically characterized. The genetic etiology of most pituitary tumours remains unknown. Pituitary adenomas can develop sporadically or as a part of multiple endocrine neoplasia type 1. In this review, the recently published data on the pathology of the MEN 1 syndrome will be summarized. The clinical, morphological and genetic aspects of sporadic and MEN 1-associated pituitary adenomas will be outlined.