A New Pattern of Multiple Endocrine Adenomatosis

Beyond the "3 Ps": A critical appraisal of the non-endocrine manifestations of multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN1), an autosomal-dominantly inherited tumor syndrome, is classically defined by tumors arising from the "3 Ps": Parathyroids, Pituitary, and the endocrine Pancreas. From its earliest descriptions, MEN1 has been associated with other endocrine and non-endocrine neoplastic manifestations. High quality evidence supports a direct association between pathogenic MEN1 variants and neoplasms of the skin (angiofibromas and collagenomas), adipose tissue (lipomas and hibernomas), and smooth muscle (leiomyomas). Although CNS tumors, melanoma, and, most recently, breast cancer have been reported as MEN1 clinical manifestations, the published evidence to date is not yet sufficient to establish causality. Well-designed, multicenter prospective studies will help us to understand better the relationship of these tumors to MEN1, in addition to verifying the true prevalence and penetrance of the well-documented neoplastic associations. Nevertheless, patients affected by MEN1 should be aware of these non-endocrine manifestations, and providers should be encouraged always to think beyond the "3 Ps" when treating an MEN1 patient.

The 3PAs: An Update on the Association of Pheochromocytomas, Paragangliomas, and Pituitary Tumors

Pituitary adenomas (PA) and pheochromocytomas/paragangliomas (PHEO/PGL) are rare tumors. Although they may co-exist by coincidence, there is mounting evidence that genes predisposing in PHEO/PGL development, may play a role in pituitary tumorigenesis. In 2012, we described a GH-secreting PA caused by an SDHD mutation in a patient with familial PGLs and found loss of heterozygosity at the SDHD locus in the pituitary tumor, along with increased hypoxia-inducible factor 1α (HIF-1α) levels. Additional patients with PAs and SDHx defects have since been reported. Overall, prevalence of SDHx mutations in PA is very rare (0.3-1.8% in unselected cases) but we and others have identified several cases of PAs with PHEOs/PGLs, like our original report, a condition which we termed the 3 P association (3PAs). Interestingly, when 3PAs is found in the sporadic setting, no SDHx defects were identified, whereas in familial PGLs, SDHx mutations were identified in 62.5-75% of the reported cases. Hence, pituitary surveillance is recommended among patients with SDHx defects. It is possible that the SDHx germline mutation-negative 3PAs cases may be due to another gene, epigenetic changes, mutations in modifier genes, mosaicism, somatic mutations, pituitary hyperplasia due to ectopic hypothalamic hormone secretion or a coincidence. PA in 3PAs are mainly macroadenomas, more aggressive, more resistant to somatostatin analogues, and often require surgery. Using the Sdhb +/- mouse model, we showed that hyperplasia may be the first abnormality in tumorigenesis as initial response to pseudohypoxia. We also propose surveillance and follow-up approach of patients presenting with this association.

15 YEARS OF PARAGANGLIOMA: The association of pituitary adenomas and phaeochromocytomas or paragangliomas

The combination of pituitary adenomas (PA) and phaeochromocytomas (phaeo) or paragangliomas (PGL) is a rare event. Although these endocrine tumours may occur together by coincidence, there is mounting evidence that, in at least some cases, classical phaeo/PGL-predisposing genes may also play a role in pituitary tumorigenesis. A new condition that we termed '3Pas' for the association of PA with phaeo and/or PGL was recently described in patients with succinate dehydrogenase mutations and PAs. It should also be noted that the classical tumour suppressor gene, MEN1 that is the archetype of the PA-predisposing genes, is also rarely associated with phaeos in both mice and humans with MEN1 defects. In this report, we review the data leading to the discovery of 3PAs, other associations linking PAs with phaeos and/or PGLs, and the corresponding clinical and molecular genetics.

Multiple leiomyomas of the esophagus, lung, and uterus in multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary disorder characterized by multiple parathyroid, pancreatic, duodenal, and pituitary neuroendocrine tumors. Nonendocrine mesenchymal tumors, such as lipomas, collagenomas, and angiofibromas have also been reported. MEN1-associated neuroendocrine and some mesenchymal tumors have documented MEN1 gene alterations on chromosome 11q13. To test whether the MEN1 gene is involved in the pathogenesis of multiple smooth muscle tumors, we examined the 11q13 loss of heterozygosity (LOH) and clonality patterns in 15 leiomyomata of the esophagus, lung, and uterus from five patients with MEN1. Forty sporadic uterine leiomyomata were also studied for 11q13 LOH. LOH analysis was performed using four polymorphic DNA markers at the MEN1 gene locus; D11S480, PYGM, D11S449, and INT-2. 11q13 LOH was detected in 10 of 12 (83%) MEN1-associated esophageal and uterine smooth muscle tumors. In contrast, LOH at the MEN1 gene locus was demonstrated only in 2 of 40 (5%) sporadic uterine tumors. LOH at 11q13 was not documented in three lung smooth muscle tumors from a single patient with MEN1. Ten tumors from two female patients were additionally assessed for clonality by X-chromosome inactivation analysis. The results demonstrated different clonality patterns in multiple tumors in the same organ in each individual patient. The data indicate that leiomyomata of the esophagus and uterus in MEN1 patients arise as independent clones, develop through MEN1 gene alterations, and are an integral part of MEN1. However, the MEN1 gene is not a significant contributor to the tumorigenesis of sporadic uterine leiomyomata.

Diagnostic challenges in the fine-needle aspiration diagnosis of carotid body paragangliomas: report of two cases

Two cases of carotid body paragangliomas sampled by fine-needle aspiration (FNA) cytology prior to other medical diagnostic studies are presented. In the first case, the presence of an ipsilateral ulcerative lesion of the nasopharynx along with pronounced atypia of the specimen posed a challenge to the correct cytologic interpretation, which was initially sidetracked in favor of a metastatic epithelial lesion. In the second case, a tumor mass of unusually large size and extension which included the pharynx, coupled with a large amount of profusely hemorrhagic aspirate, presented a diagnostic problem, which was overcome by processing part of the specimen as a cell block, which by its histologic and immunochemical features provided a definitive pathologic diagnosis. In handling these two clinically complex cases of carotid paraganglioma, two learning principles became clear on how to reach a correct FNA diagnosis in such lesions: 1) The anatomic location of the lateral neck mass with its prolonged history, along with a hemorrhagic FNA specimen exhibiting at least some cytologic features reminiscent of endocrine neoplasm, are among the factors that help in arriving at a suggestive diagnosis of paraganglioma, when other clinical features tend to sidetrack from interpretation of the cytologic changes. 2) In the practice of FNA cytology, if the possibility of paraganglioma arises, processing part of the specimen as a cell block with accompanying histology and immunohistochemistry can provide a definitive diagnosis of such lesion.

Carotid body tumor associated with hyperparathyroidism

Hyperparathyroidism in association with carotid body tumor is a rare combination. A common embryologic cellular origin was postulated previously to explain this unusual occurrence. We report a case of left carotid body tumor and left inferior parathyroid adenoma. We believe this to be the sixth reported case in the literature with this combination.

Dominant familial syndromes with endocrine hyperfunction: An additional syndrome?

At least 8 separate dominant syndromes have been described which have hyperfunctioning endocrine tumors as an important component. Scattered reports in the literature suggest that there may be an additional syndrome, in which extra-adrenal paragangliomas (often multiple), pituitary adenomas, and parathyroid hyperplasia coexist. Of 3 such cases described to date, 2 have included information about the family history, which in each case suggested dominant inheritance. This would presumably be a less common syndrome than the others recognized previously, so that full evaluation of endocrine findings and family history in future cases will be important for developing our understanding of the syndrome.

Multiple endocrine neoplasia: how many syndromes?

The phrase multiple endocrine neoplasia (MEN) generally denotes an association of tumors so specific as to constitute a syndrome. Three well-recognized such syndromes exist. All are autosomal dominant traits and all have been tentatively mapped to specific chromosomes. Other purported endocrine tumor syndromes have been suggested either as new entities or as subtypes of the existing MEN syndromes. The evidence in favor of these contentions is examined critically. Only one "new" association, that of pheochromocytomas and islet cell tumors, seems reasonable, and even in this setting, some relatives have had manifestations of von Hippel-Lindau syndrome. There is no compelling reason why such conditions as von Hippel-Lindau syndrome, peripheral neurofibromatosis, McCune-Albright syndrome, and others should be reclassified as MEN syndromes, although awareness of their collective endocrine abnormalities is clinically important.

Malignant insulinoma with metastasis to gallbladder and bone, accompanied by past history of peptic ulcer and hyperthyroidism

A case of a malignant insulinoma in a 53-year-old female is presented. In 1973, the patient underwent caudal pancreatectomy for a malignant insulinoma. Ten years later, it was discovered that the insulinoma had spread to the bones. On admission for cholecystectomy because of a gallbladder polyp and gallstones, she often experienced hypoglycemic attacks, and both calcium and glucagon provocation tests elicited marked release of insulin. Selective angiography of the common hepatic artery showed a tumor blush near the hilum of the liver. Immunohistochemical staining of the gallbladder polyp and the bone tumors proved positive for insulin. Plasma levels of insulin and prolactin were abnormally high. The patient had also been treated for a perforated duodenal ulcer and hyperthyroidism. It is concluded that this may have been a case of a multiple endocrine neoplasia.

Clinical significance of the association of the Von Hippel-Lindau disease with pheochromocytoma and pancreatic apudoma

Von Hippel-Lindau disease (VHLD) is a rare disorder known to occur with pheochromocytoma. We report a case with this association and also with pancreatic apudoma. We believe that this is the fifth reported case of this triad, which represents an overlap in the multiple endocrine neoplasia (MEN) classification. Many recent reports of overlap of MEN syndromes challenge the validity of this classification. New understanding of the embryologic origin of cells of endocrine organs has led to the elucidation of the APUD (amine precursor uptake and decarboxylation)-neuroendocrine system. Integration of the APUD system may be important to understanding the pathogenesis of the MEN-like syndromes as well as their relationship to the neurocutaneous syndromes. Any endocrine tumor or neurocutaneous syndrome should be evaluated to exclude a spectrum of possible associations.

Malignant catecholamine-secreting carotid body paraganglioma

The second known case of a malignant catecholamine-secreting (DA)-secreting carotid body paraganglioma is presented. Dopamine synthesis and secretion can be increased in malignant tumors derived from neural crest cells. Whether this is true, in addition, for extra-adrenal paragangliomas is not yet clear. Malignant paragangliomas of the carotid body and larynx, although rare, frequently have been accompanied by increased catecholamine secretion. Malignant catecholamine-secreting carotid body paragangliomas are best treated by composite resection (internal carotid artery and neck dissection), with special attention being given to measures preventing severe hypertension and arrhythmias in the perioperative period.

Neck paraganglioma with a pituitary adenoma. Case report

✓ A 66-year-old man presented for evaluation of a mass of the sella turcica. Previously, he had undergone resection of a neck paraganglioma, which subsequently metastasized to the lungs. A tumor was removed transsphenoidally that proved to be a pituitary adenoma. This combination failed to fit the classical multiple endocrine neoplasia syndromes.

Familial carotid body tumors: case report and epidemiologic review

We report on the cases of two sisters with carotid body tumor (CBT) and present a literature review that assembles epidemiologic information on 88 familial and 835 nonfamilial CBT patients. The sex ratio (males/females) of 1.0 for familial CBT (0.7 for nonfamilial) and CBT reports with complete sibship information suggest autosomal dominant genetic transmission. As in other familial cancers, bilateral disease is significantly more frequent in familial (31.8% of cases) than in nonfamilial CBT (4.4%). However, there is no difference in age at diagnosis between familial and nonfamilial CBR. Thus, this adult-onset familial cancer does not completely fit the Knudson "two-step mutation" model of carcinogenesis. We also found that 6% of reported CBT patients developed second primary tumors, mostly other paragangliomas. This feature suggests that CBT may be part of a larger neurocristopathy syndrome of multiple tumors of cells of neural crest origin.

Aortic body tumours and hyperplasia in the rat

The histologic features of aortic body neoplasia, hyperplasia, and normal aortico-pulmonary paraganglia were described for a series of 56 rats of several strains. Argyrophilic cytoplasmic granules were demonstrated in chief cells of the aortic body lesions, and electron microscopic examination disclosed the presence of electron-dense, membrane-bound granules in these cells. In a series of ageing rats, hyperplasia and neoplasia of the aortico-pulmonary paraganglia occurred more frequently in female WAG/Rij rats than in males of that strain, and more frequently than in males and females of the BN/Bi strain or of the (WAG X BN)F1 hybrid. No apparent causal relationship to chronic hypoxia could be shown, in that no correlation between the development of aortic body neoplasia or hyperplasia and cardiopulmonary disease was found. Aortic body lesions did not appear to occur as part of a multiple endocrinopathy syndrome, although hyperplasia and neoplasia of various endocrine organs occurred relatively frequently in the WAG/Rij strain.