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Composite pheochromocytoma (CP) is a very rare tumor originating from neural crest cells, predominantly composed of pheochromocytoma (PCC), a chromaffin cell tumor arising in adrenal medulla, and ganglioneuroma, a tumor derived from autonomic ganglion cells of the nervous system. Moreover, CP may be present in the hereditary syndromes of which pheochromocytoma is part. Literature offers scarce data on this subject, and particularly about its biological behavior, clinical evolution, and molecular profile. We report the phenotype and outcome of three cases of CP (PCC and ganglioneuroma components), followed up at the Endocrine Service of the Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil. Two nonsyndromic patients (cases 1 and 2) were negative to germline mutations in genes VHL, SDHB, SDHC, SDHD, SDHAF2, TMEM127, and MAX, while the third case (case 3) had clinical diagnosis of neurofibromatosis syndrome. Cases 1, 2, and 3 were diagnosed at 29, 39, and 47 years old, respectively, and were followed up for 3, 17, and 9 years without no CP recurrence. All cases had apparent symptoms of catecholaminergic excess secreted by PCC. Ganglioneuroma, the neurogenic component present in all three cases, had a percentage representation ranging from 5% to 15%. Tumors were unilateral and large, measuring 7.0 cm × 6.0 cm × 6.0 cm, 6.0 cm × 4.0 cm × 3.2 cm, and 7.5 cm × 6.0 cm × 4.5 cm, respectively. All cases underwent adrenalectomy with no recurrence, metastasis, or development of contralateral tumor during follow-up. Genetic testing has been scarcely offered to CP cases. However, a similar frequency of genetic background is found when compared with classic PCC, mainly by the overrepresentation of NF1 cases in the CP subset. By literature review, we identified a notorious increase in cases reported with CP in the last decade, especially in the last 3 years, indicating a recent improvement in the diagnosis of this rare disorder in clinical practice.

Context Von Hippel-Lindau (VHL) disease is an autosomal dominant syndrome caused by germline mutations in the VHL gene. Guidelines recommend pheochromocytoma (PHEO) biochemical screening should start at age 5 years. Objective Genotype–phenotype correlations in VHL, focusing on PHEO penetrance in children, were studied. Design We retrospectively evaluated 31 individuals (median age at diagnosis was 26 years) with diagnosed VHL disease. Results PHEO was diagnosed in six children with VHL. A large PHEO (5 cm) was detected in a 4-year-old boy with p.Gly114Ser mutation. PHEO penetrance was 55% starting at age 4 years. VHL missense mutations were identified in 11 of 22 families (50%), frameshift mutations in four (18.2%), stop codon in three (13.6%), splicing site in two (9.1%), and large gene deletion in two (9.1%). The codon 167 (n = 10) was a hotspot for VHL mutations and was significantly associated with PHEO (90% vs. 38%; P = 0.007). PHEOs and pancreatic neuroendocrine tumors (PNETs) were strongly associated with VHL missense mutations compared with other mutations (89.5% vs. 0% and 73.7% vs. 16.7%; P = 0.0001 and 0.002, respectively). In contrast, pancreatic cysts (91.7% vs. 26.3%; P = 0.0001), renal cysts (66.7% vs. 26.3%; P = 0.027), and central nervous system hemangioblastomas (91.7% vs. 47.3%; P = 0.012) were more frequent in VHL with nonmissense mutations. Conclusion VHL missense mutations were highly associated with PHEO and PNETs. Our data support that in children with VHL harboring missense mutations, biochemical screening for PHEO should be initiated at diagnosis.

Scarce data are available on the quality of life and psychosocial distress of patients with multiple endocrine neoplasia type 2 (MEN2), a genetic cancer syndrome caused by RET germline mutations. Carriers of RET mutations can face several challenges, including fear for the future, guilt for transmission of a germline mutation to an offspring, side effects of cancer treatment, coping behaviors in the face of a chronic and frequently incurable cancer, and difficulties in access to adequate health care. We have addressed the effects of genetic testing on the quality of life of patients with MEN2 and the lifelong physical and psychosocial challenges experienced by these patients. We have also suggested strategies to minimize the burden of living with this chronic condition and the perspectives on future studies to improve the health-related quality of life of the patients.

Background Loss-of-function germline MEN1 gene mutations account for 75–95% of patients with multiple endocrine neoplasia type 1 (MEN1). It has been postulated that mutations in non-coding regions of MEN1 might occur in some of the remaining patients; however, this hypothesis has not yet been fully investigated. Objective To sequence for the entire MEN1 including promoter, exons and introns in a large MEN1 cohort and determine the mutation profile. Methods and patients A target next-generation sequencing (tNGS) assay comprising 7.2 kb of the full MEN1 was developed to investigate germline mutations in 76 unrelated MEN1 probands (49 familial, 27 sporadic). tNGS results were validated by Sanger sequencing (SS), and multiplex ligation-dependent probe amplification (MLPA) assay was applied when no mutations were identifiable by both tNGS and SS. Results Germline MEN1 variants were verified in coding region and splicing sites of 57/76 patients (74%) by both tNGS and SS (100% reproducibility). Thirty-eight different pathogenic or likely pathogenic variants were identified, including 13 new and six recurrent variants. Three large deletions were detected by MLPA only. No mutation was detected in 16 patients. In untranslated, regulatory or in deep intronic MEN1 regions of the 76 MEN1 cases, no point or short indel pathogenic variants were found in untranslated, although 33 benign/likely benign and three new VUS variants were detected. Conclusions Our study documents that point or short indel mutations in non-coding regions of MEN1 are very rare events. Also, tNGS proved to be a highly effective technology for routine genetic MEN1 testing.

Paraganglioma, HIF-2α, and Cyanotic Heart Disease Four of five patients with paragangliomas and pheochromocytomas who had received a diagnosis of congenital cyanotic heart disease had mutant HIF-2α. This contrasts with the prevalence of mutant HIF-2 in these tumor types in the absence of cyanotic heart disease (6 to 10%).

Background: Surgery is the elective therapy for primary hyperparathyroidism (HPT) in patients with multiple endocrine neoplasia type 1 (MEN1). As MEN1 mutation carriers invariably will develop HPT up to 50 years, the annual periodic screening have allowed an early diagnosis of HPT in MEN1 syndrome, frequently before manifestation of clinical symptoms. Health-related quality of life (HR-QoL) both before after parathyroidectomy (PTx) has been poorly described. As the ideal timing to indicate PTx is yet controversial and undefined and, most recently, the value of less extensive surgeries has been considered for some groups, data on HR-QoL may be useful to clarify better these conflicting issues. Objectives: To investigate post-operative HR-QoL aspects of patients submitted to PTx for MEN1-related HPT (HPT/MEN1). Methods: Prospective analysis of HPT/MEN1 patients submitted to total PTx with immediate forearm autograft (TPTx+A) or subtotal parathyroidectomy (SPTx) in single institution. A psychologist applied Short Form 36 Health Survey Questionnaire immediately before and 6 months after surgery. Changes of both Physical Component Summary Score (PCS) and Mental Component Summary Score (MCS) were analyzed considering persistence of HPT, hypoparathyroidism and pancreatectomy after the PTx. Results: Of 19 patients (mean age 38.4±14.4, 7 men), 8 underwent TPTx+A and 11 had SPTx. Overall, median (interquartiles ranges) of pre-operative PCS and MCS were 73.8 (50.0-88.0) and 65.0 (44.5-83.2), respectively. At 6 months, median PCS was 71.2 (55.8-91.0) and median MCS was 80.2 (46.8-88.0). There were five (4, PTxT+A; 1, SPTx) patients with postoperative hypoparathyroidism, one with persistent HPT (SPTx) and 13 with normal parathyroid function (4, TPTx+A; 9, SPTx) six months after PTx. PCS worsened in four cases with hypoparathyroidism (80%) and in five euparathyroid (36%), but without statistical significance (p, 0.14). MCS worsened in four cases with hypoparathyroidism (80%), but in only one euparathyroid (7%) (p, 0.0061). The worst decrease of both PCS and MCS occurred in two patients submitted to pancreatectomy during the follow-up after parathyroidectomy (PCS decreased 79% in one case and 53% in the other; MCS decreased 75% and 37%, respectively). Conclusion: Hypoparathyroidism worsens the HR-QoL after PTx in HPT/MEN1, particularly in patients undergoing subsequent pancreatectomy.

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant genetic disease caused by RET gene germline mutations that is characterized by medullary thyroid carcinoma (MTC) associated with other endocrine tumors. Several reports have demonstrated that the RET mutation profile may vary according to the geographical area. In this study, we collected clinical and molecular data from 554 patients with surgically confirmed MTC from 176 families with MEN2 in 18 different Brazilian centers to compare the type and prevalence of RET mutations with those from other countries. The most frequent mutations, classified by the number of families affected, occur in codon 634, exon 11 (76 families), followed by codon 918, exon 16 (34 families: 26 with M918T and 8 with M918V) and codon 804, exon 14 (22 families: 15 with V804M and 7 with V804L). When compared with other major published series from Europe, there are several similarities and some differences. While the mutations in codons C618, C620, C630, E768 and S891 present a similar prevalence, some mutations have a lower prevalence in Brazil, and others are found mainly in Brazil (G533C and M918V). These results reflect the singular proportion of European, Amerindian and African ancestries in the Brazilian mosaic genome.

Context: Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant genetic syndrome caused by germline pathogenic allele variants (PAV) in the MEN1 tumor suppressor gene, which predispose MEN1 carriers to the increased risk of several endocrine neoplasms throughout life. The MEN1 gene (11q13), contains 10 exons encoding the MENIN protein. About 600 different PAVs have been reported, with 25% of them being missense variants. Of value, the definition of pathogenicity can be challenging, especially for missense variants. Thus, international guidelines for improving the classification of allele variants were recently defined by the ACMG-AMP (2015). Recently, applying ACMG-AMP criteria with inclusion of clinical features the TENGEN French group suggested modifications aiming to refine the classification of variants in MEN1 syndrome. Objective: To classify missense allelic variants found in the MEN1 gene by the ACMG-AMP guideline using VARSOME and by the TENGEN group to support a comparative analysis of the results obtained with these two methodologies (ACMG-AMP; TENGEN). Methods: the classification of 16 different missense allele variants identified in 17 index cases with or suspected to MEN1 syndrome was conducted according to ACMG-AMP criteria using the VARSOME software followed by the analysis defined by the TENGEN group. Results: Of the 16 variants, 6 were new, 1 was recurrent (2 unrelated index cases) and 9 of them occurred in codons with previous reports of different amino acid exchanges in the same region. Differences observed in the classification by ACMG-AMP and TENGEN were: pathogenic variant (6% vs. 65%); probably pathogenic (88% vs. 12%) and variants of uncertain significance (VUS) (6% vs. 23%). The four VUS classified by TENGEN (one of them for ACMG-AMP) were of sporadic cases without clinical diagnosis of MEN1 (2, for one MEN1-related tumor in early age; 1, for suspected MEN1) or with high risk of phenocopy (1, HPT + acromegaly). Conclusion: The difference observed in the classification of the pathogenicity of these variants, especially due to the higher occurrence of VUS in TENGEN, indicates that the criteria adopted by ACMG-VARSOME would have to be refined for clinical features. By other side, TENGEN apparently reinforce the classification of pathogenicity in cases with clinical diagnosis of MEN1 and reduce the definition of pathogenicity to variants found in MEN1-suspected cases without clinical criteria for the MEN1 diagnosis. These protocols apparently need to be investigate, validated and, probably, improved in other cohorts to reduce risks of misinterpretations and classifications that can, lately, interfere in genetic counseling and in the clinical management of patients. Finally, long-term outcome of cases classified as VUS, functional studies and, familial segregation may reinforce the initial impressions obtained with TENGEN classification.

Multiple endocrine neoplasia type 1 (MEN1) is a heterogeneous disorder, with tumors among some 30 different tissue types (1). The tumors may be hormone-secreting or hormone non-secreting. The tumors are expressed mainly in adults; however, the penetrance of primary hyperparathyroidism (PHPT) in MEN1 is already around 50% by age 20 years (2). Few MEN1 series focusing on children have been described or collected (2–5). Thus, it is not possible to make well-supported assessments about many issues on this topic. In this article, we highlight and provide opinions about important issues that are unresolved or even controversial. Most issues focus on the parathyroids in MEN1. Some of these issues may have a different approach in other articles of this volume.

Insulinoma is a rare pancreatic tumor and, usually, a benign disease but can be a malignant one and, sometimes, a highly aggressive disease. The aim of this study was to determine differences between benign and malignant tumors.Retrospective study of 103 patients with insulinoma treated in a tertiary center. It was analyzed demographic, clinical, laboratory, localization and histologic analysis of tumor and follow up data of subjects in order to identify differences between individuals benign and malignant disease.Almost all patients (87%) had a benign tumor and survival rates of 100% following pancreatic tumor surgery. Those with malignant tumors (13%) have a poor prognosis, 77% insulinoma-related deaths over a period of 1-300 months after the diagnosis with a survival rate of 24% in five years. The following factors are associated with an increased risk of malignant disease: duration of symptoms 24 months, fasting time for the occurrence of hypoglycemia 8 h, blood plasma insulin concentration ≥ 28 μU/mL and C-peptide ≥ 4.0 ng/mL at the glycemic nadir and tumor size ≥ 2.5 cm.Our data help to base the literature about these tumors, reinforcing that although insulinoma is usually a single benign and surgically treated neoplasia, the malignant one is difficult to treat. We highlight the data that help predict a malignancy behavior of tumor and suggest a long follow up after diagnosis in these cases.

Six syndromes of familial hyperparathyroidism are compared: 1) Familial hypocalciuric hypercalcemia (FHH) expresses primary hyperparathyroidism (PHPT) beginning at birth with lifelong hypercalcemia. There is nonsuppressed PTH secretion from outwardly normal parathyroid glands. It reflects germline heterozygous mutation in CASR, GNA11, or AP2S1. 2) Neonatal severe primary hyperparathyroidism is severest of the six syndromes. It requires urgent total parathyroidectomy in infancy. It usually reflects biallelic inactivation of the CASR. 3) Multiple endocrine neoplasia type 1 (MEN1) is most frequently expressed as PHPT with asymmetric enlargement of 3–4 parathyroids. Benign or malignant tumors may occur among 30 other tissues. It is predisposed by germline inactivation of MEN1 or rarely by inactivation of a cyclin dependent kinase inhibitor, and then termed MEN4. 4) Multiple endocrine neoplasia type 2A from RET activating mutation rarely presents as familial hyperparathyroidism, because medullary thyroid cancer and pheochromocytoma are more prominent. 5) Hyperparathyroidism-jaw tumor syndrome (HPT-JT) has frequent PHPT and benign jaw tumors. Twenty percent develop parathyroid cancer. It is predisposed by inactivating mutation in CDC73. 6) Familial isolated hyperparathyroidism causes multiple parathyroid tumors. It can be an incomplete expression of FHH, MEN1, HPT-JT or even of relatives without a shared driver mutation. However, in 20% of families it reflects GCM2 activating mutation. Five of the PHPT syndromes reflect overgrowth of parathyroid tissue; in contrast, familial hypocalciuric hypercalcemia reflects dysregulation of PTH secretion with little or no parathyroid overgrowth. These differences underlie major differences in clinical expression.

Data on psychological harm in multiple endocrine neoplasia type 2 (MEN2) are scarce.The aim of this study was to assess anxiety, depression, quality of life, and coping in long-standing MEN2 patients.Patients were 43 adults (age ≥18 years) with clinical and genetic diagnosis of MEN2 and long-term follow-up (10.6 ± 8.2 years; range 1-33 years). This was a cross-sectional study with qualitative and quantitative psychological assessment using semi-directed interviews and HADS, EORTC QLQ C30, and MINI-MAC scales. Adopting clinical criteria from 2015 ATA Guidelines on MEN2, biochemical cure (39%; 16/41), persistence/recurrence (61%; 25/41), and stable chronic disease (22/41) of medullary thyroid carcinoma (MTC) were scored. Pheochromocytoma affected 19 (44%) patients, with previous adrenalectomy in 17 of them.Overall, anxiety (42%; mean score 11 ± 2.9; range 8-18; anxiety is defined as a score ≥8) and depression (26%; mean score 11 ± 3.8; range 8-20; depression is defined as a score ≥8) symptoms were frequent. Patients who transmitted RET mutations to a child had higher scores for weakness-discouragement/anxious preoccupation and lower scores for cognitive, emotional, and physical functioning (p 0.05). Feelings of guilt were present in 35% of patients with mutation-positive children. Lower mean score values for depression and anxiety and higher scores for role, cognitive, and emotional functioning were noticed in 33 patients who were well-informed about their disease (p 0.05). Fighting spirit was more frequently found in patients with multiple surgical procedures (p = 0.019) and controlled chronic adrenal insufficiency (p = 0.024). Patients with MEN2-related stress-inducing factors had lower scores for fighting spirit and cognitive functioning and higher scores for insomnia and dyspnea (p 0.05). Eleven patients required sustained psychotherapeutic treatment. Mean global health status was relatively good in MEN2 cases (68.1 ± 22.3), and the cured group had higher physical functioning (p = 0.021).Psychological distress is likely chronic in MEN2 patients. This study identified diverse MEN2-related factors (degree of information on disease, mutation-positive children, number of surgeries, comorbidities, stress-inducing factors, and cure) interfering positively or negatively with the results of the psychometrics scales. The active investigation of these factors and the applied psychological assessment protocol are useful to identify MEN2 patients requiring psychological assistance.

The treatment of advanced medullary thyroid carcinoma (MTC) has evolved significantly over the past decade. The discovery of genetic abnormalities in MTC has led to the development of targeted therapies such as vandetanib and cabozantinib. Other kinase inhibitors (KI), such as sorafenib, have been investigated in this setting and are an alternative therapeutic option. The lack of specificity of these KIs to a single target may result in additional, unexpected effects. In this report, we describe a patient with metastatic MTC and Ectopic ACTH (adrenocorticotropic hormone) Syndrome in whom treatment with sorafenib resulted in complete resolution of hypercortisolism.A 45-year-old male with progressive metastatic MTC presented with clinical manifestations suspicious for Cushing's syndrome. Investigation revealed ACTH-dependent hypercortisolism suggestive of Ectopic ACTH Syndrome. Treatment with sorafenib 400 mg twice a day was initiated resulting in a rapid and significant reduction of cortisol and ACTH levels associated with dramatic clinical improvement. The rapid and effective control of hypercortisolism in the absence of a significant tumor reduction raises the question of whether sorafenib may have a direct effect on ACTH or cortisol hypersecretion.This report suggests a previously unknown potential effect of sorafenib on the pituitary-adrenal axis. Further studies will be necessary to investigate the role of sorafenib in other cases of ACTH excess and to understand the mechanisms by which it alters steroid synthesis, action, or secretion.

After a total parathyroidectomy, well-established protocols for the cryopreservation of parathyroid tissue and for the delayed autograft of this tissue exist, especially in cases of secondary hiperparathyroidism (HPT) or familial or sporadic parathyroid hyperplasia. Although delayed autografts are effective, the published success rates vary from 10% to 83%. There are numerous factors that influence the viability, and therefore the success, of an autograft, including cryopreservation time. Certain authors believe that the tissue is only viable for 24 months, but there is no consensus on how long the parathyroid tissue can be preserved. A 63-year-old male who was diagnosed with sporadic multiple endocrine neoplasia type 1 and primary hyperparathyroidism, and was submitted to a total parathyroidectomy and an autograft in the forearm. The implant failed, and the patient developed severe hypoparathyroidism in the months following the surgery. Thirty-six months after the total parathyroidectomy, the cryopreserved autograft was successfully transplanted, and hypoparathyroidism was reversed (most recent systemic parathyroid hormone, PTH, of 36 pg/mL, and total calcium of 9.1 mg/dL; no oral calcium supplementation). The case presented here indicates that cryopreserved parathyroid tissue may remain viable after 24 months in storage, and may retain the capacity to reverse permanent postsurgical hypoparathyroidism. These data provide reasonable evidence that the time limit for cryopreservation remains undetermined and that additional research would be valuable. Arq Bras Endocrinol Metab. 2014;58(3):313-6

Data are scarce on the penetrance of multiple endocrine neoplasia type 1 (MEN1)-related nonfunctioning pancreatic neuroendocrine tumors (NF-PETs) and insulinomas in young MEN1 patients. A potential positive correlation between tumor size and malignancy (2-3 cm, 18%;3 cm, 43%) has greatly influenced the management of MEN1 adults with NF-PETs.The aim of the study was to estimate the penetrance of NF-PETs, insulinomas, and gastrinomas in young MEN1 carriers.The data were obtained from a screening program (1996-2012) involving 113 MEN1 patients in a tertiary academic reference center.Nineteen MEN1 patients (aged 12-20 y; 16 patients aged 15-20 y and 3 patients aged 12-14 y) were screened for NF-PETs, insulinomas, and gastrinomas.Magnetic resonance imaging/computed tomography and endoscopic ultrasound (EUS) were performed on 10 MEN1 carriers, magnetic resonance imaging/computed tomography was performed on five patients, and four other patients underwent an EUS.The overall penetrance of PETs during the second decade of life was 42% (8 of 19). All eight PET patients had NF-PETs, and half of those tumors were multicentric. One-fifth of the screened patients (21%; 4 of 19) harbored at least one large tumor (2.0 cm). Insulinoma was detected in two NF-PET patients (11%) at the initial screening; gastrinoma was not present in any cases. Six of the 11 (54%) screened patients aged 15-20 years who underwent an EUS had NF-PETs. Potential false-positive EUS results were excluded based on EUS-guided biopsy results, the reproducibility of the NF-PET findings, or the observation of increased tumor size during follow-up. Distal pancreatectomy and the nodule enucleation of pancreatic head tumors were conducted on three patients with large tumors (2.0 cm; T2N0M0) that were classified as grade 1 neuroendocrine tumors (Ki-672%).Our data demonstrated high penetrance of NF-PETs in 15- to 20-year-old MEN1 patients. The high percentage of the patients presenting consensus criteria for surgery for NF-PET alone or NF-PET/insulinoma suggests a potential benefit for the periodic surveillance of these tumors in this age group.

Differences in bone mineral density (BMD) patterns have been recently reported between multiple endocrine neoplasia type 1–related primary hyperparathyroidism (HPT/MEN1) and sporadic primary HPT. However, studies on the early and later outcomes of bone/renal complications in HPT/MEN1 are lacking. In this cross-sectional study, performed in a tertiary academic hospital, 36 patients cases with uncontrolled HPT from 8 unrelated MEN1 families underwent dual-energy X-ray absorptiometry (DXA) scanning of the proximal one-third of the distal radius (1/3DR), femoral neck, total hip, and lumbar spine (LS). The mean age of the patients was 38.9 ± 14.5 years. Parathyroid hormone (PTH)/calcium values were mildly elevated despite an overall high percentage of bone demineralization (77.8%). In the younger group ( 50 years of age) had a higher frequency of bone demineralization at all sites (p 10 years) and gastrinoma/HPT presented significantly lower 1/3DR BMD values. Urolithiasis occurred earlier (

Summary Objective Limited data have been reported on the effect of parathyroidectomy (PTx) on bone mineral density (BMD) in the setting of patients with hyperparathyroidism (HPT) associated with multiple endocrine neoplasia type 1 (MEN1). This study investigates the impact of total PTx on BMD in patients with HPT/MEN1. Design and patients A case series study was performed in a tertiary academic hospital. A total of 16 HPT/MEN1 patients from six families harbouring MEN1 germline mutations were subjected to total PTx followed by parathyroid auto-implant in the forearm. Measurements Bone mineral density values were assessed using dual-energy X-ray absorptiometry. Results Before PTx, reduced BMD (Z-score

Hypercalcitoninemia has frequently been reported as a marker for medullary thyroid carcinoma. Currently, calcitonin measurements are mostly useful in the evaluation of tumor size and progression, and as an index of biochemical improvement of medullary thyroid carcinomas. Although measurement of calcitonin is a highly sensitive method for the detection of medullary thyroid carcinoma, it presents a low specificity for this tumor. Several physiologic and pathologic conditions other than medullary thyroid carcinoma have been associated with increased levels of calcitonin. Several cases of thyroid nodules associated with increased values of calcitonin are not medullary thyroid carcinomas, but rather are related to other conditions, such as hypercalcemias, hypergastrinemias, neuroendocrine tumors, renal insufficiency, papillary and follicular thyroid carcinomas, and goiter. Furthermore, prolonged treatment with omeprazole (2-4 months), beta-blockers, glucocorticoids and potential secretagogues, have been associated with hypercalcitoninemia. An association between calcitonin levels and chronic auto-immune thyroiditis remains controversial. Patients with calcitonin levels100 pg/mL have a high risk for medullary thyroid carcinoma (approximately 90%-100%), whereas patients with values from 10 to 100 pg/mL (normal values:8.5 pg/mL for men,5.0 pg/mL for women; immunochemiluminometric assay) have a25% risk for medullary thyroid carcinoma.In multiple endocrine neoplasia type 2 (MEN2), RET mutation analysis is the gold-standard for the recommendation of total preventive thyroidectomy to relatives at risk of harboring a germline RET mutation (50%). False-positive calcitonin results within MEN2 families have led to incorrect indications of preventive total thyroidectomy to RET mutation negative relatives. In this review, we focus on the differential diagnosis of hypercalcitoninemia, underlining its importance for the avoidance of misdiagnosis of medullary thyroid carcinoma and consequent incorrect recommendation for thyroid surgery.

INTRODUCTION: Medullary thyroid carcinoma may occur in a sporadic (s-medullary thyroid carcinoma, 75%) or in a multiple endocrine neoplasia type 2 form (MEN2, 25%). These clinical forms differ in many ways, as s-medullary thyroid carcinoma cases are RET-negative in the germline and are typically diagnosed later than medullary thyroid carcinoma in MEN2 patients. In this study, a set of cases with s-medullary thyroid carcinoma are documented and explored. PURPOSE: To document the phenotypes observed in s-medullary thyroid carcinoma cases from a university group and to attempt to improve earlier diagnosis of s-medullary thyroid carcinoma. Some procedures for diagnostics are also recommended. METHOD: Patients (n=26) with apparent s-medullary thyroid carcinoma were studied. Their clinical data were reviewed and peripheral blood was collected and screened for RET germline mutations. RESULTS: The average age at diagnosis was 43.9 years (± 10.82 SD) and did not differ between males and females. Calcitonin levels were increased in all cases. Three patients presented values that were 100-fold greater than the normal upper limit. Most (61.54%) had values that were 20-fold below this limit. Carcinoembryonic antigen levels were high in 70.6% of cases. There was no significant association between age at diagnosis, basal calcitonin levels or time of disease onset with thyroid tumor size (0.6–15 cm). Routine thyroid cytology yielded disappointing diagnostic accuracy (46.7%) in this set of cases. After total thyroidectomy associated with extensive cervical lymph node resection, calcitonin values remained lower than 5 pg/mL for at least 12 months in eight of the cases (30.8%). Immunocyto- and histochemistry for calcitonin were positive in all analyzed cases. None of the 26 cases presented germline mutations in the classical hotspots of the RET proto-oncogene. CONCLUSION: Our cases were identified late. The basal calcitonin measurements and immunostaining for calcitonin were highly useful for diagnosing s-medullary thyroid carcinoma. The rate of complete patient recovery was low, and none of the parameters analyzed were useful predictors of the thyroid tumor size. Our findings support previous recommendations for routine serum calcitonin evaluation and immunostaining analysis involving single thyroid nodules.

ObjectiveOnly few large families with multiple endocrine neoplasia type 1 (MEN1) have been documented. Here, we aimed to investigate the clinical features of a seven-generation Brazilian pedigree, which included 715 at-risk family members.DesignGenealogical and geographic analysis was used to identify the MEN1 pedigree. Clinical and genetic approach was applied to characterize the phenotypic and genotypic features of the family members.ResultsOur genetic data indicated that a founding mutation in the MEN1 gene has occurred in this extended Brazilian family. Fifty family members were diagnosed with MEN1. Very high frequencies of functioning and non-functioning MEN1-related tumors were documented and the prevalence of prolactinoma (29.6%) was similar to that previously described in prolactinoma-variant Burin (32%). In addition, bone mineral density analysis revealed severe osteoporosis (T, −2.87±0.32) of compact bone (distal radius) in hyperparathyroidism (HPT)/MEN1 patients, while marked bone mineral loss in the lumbar spine (T, −1.95±0.39), with most cancellous bone, and femoral neck (mixed composition; T, −1.48±0.27) were also present.ConclusionsIn this study, we described clinically and genetically the fifth largest MEN1 family in the literature. Our data confirm previous findings suggesting that prevalence of MEN1-related tumors in large families may differ from reports combining cumulative data of small families. Furthermore, we were able to evaluate the bone status in HPT/MEN1 cases, a subject that has been incompletely approached in the literature. We discussed the bone loss pattern found in our MEN1 patients comparing with that of patients with sporadic primary HPT.

Summary Objective To characterize clinical features and identify MEN1 germline mutations in Brazilian families with multiple endocrine neoplasia type 1 (MEN1). Settings Non-profit academic centre. Patients Fourteen Brazilian families with MEN1 and 141 at-risk relatives. Results We identified 12 different MEN1 disease-causing mutations, seven of them previously unreported: 308delC; 375del21; 549A>T (I147F); 1243delA; 1348T>G (L413R); 1351T>C (L414P) and 1523G>T (W471C). Families with the recurrent mutations 360delTCTA and L413R were shown to be unrelated by mitochondrial-DNA and Y-chromosome haplotype analyses. Most of the MEN1 single point mutations involved evolutionarily conserved residues, whereas most of the deletion/frameshift changes occurred in GC-rich repetitive regions. Genetic screening of 141 at-risk family members identified 38 MEN1 mutation carriers, 37 (97·4%) of whom had at least one major MEN1-related tumour upon clinical investigation. Conclusions High frequencies of MEN1 gene mutations were detected in Brazilian families with MEN1, including seven new genetic mutations that are predicted to cause inactivation of the MEN1 tumour suppressor gene. Our data underscore the need to implement a systematic MEN1 screening programme in Brazil.

Accurate interpretation of germline mutations of the rearranged during transfection (RET) proto-oncogene is vital for the proper recommendation of preventive thyroidectomy in medullary thyroid carcinoma (MTC)-prone carriers. To gain information regarding the most disputed variant of RET, ATA-A Y791F, we sequenced blood DNA samples from a cohort of 2904 cancer-free elderly individuals (1261 via Sanger sequencing and 1643 via whole-exome/genome sequencing). We also accessed the exome sequences of an additional 8069 individuals from non-cancer-related laboratories and public databanks as well as genetic results from the Catalogue of Somatic Mutations in Cancer (COSMIC) project. The mean allelic frequency observed in the controls was 0.0031, with higher occurrences in Central European populations (0.006/0.008). The prevalence of RET Y791F in the control databases was extremely high compared with the 40 known RET pathogenic mutations (P=0.00003), while no somatic occurrence has been reported in tumours. In this study, we report new, unrelated Brazilian individuals with germline RET Y791F-only: two tumour-free elderly controls; two individuals with sporadic MTC whose Y791F-carrying relatives did not show any evidence of tumours; and a 74-year-old phaeochromocytoma patient without MTC. Furthermore, we showed that the co-occurrence of Y791F with the strong RET C634Y mutation explains the aggressive MTC phenotypes observed in a large affected family that was initially reported as Y791F-only. Our literature review revealed that limited analyses have led to the misclassification of RET Y791F as a probable pathogenic variant and, consequently, to the occurrence of unnecessary thyroidectomies. The current study will have a substantial clinical influence, as it reveals, in a comprehensive manner, that RET Y791F only shows no association with MTC susceptibility.

Context: The phenotype of familial pheochromocytoma (PHEO) associated with germline TMEM127 mutations (TMEM127-related PHEO) has not been clearly defined. Objective: This study aimed to investigate the penetrance, full phenotypic spectrum and effectiveness of clinical/genetic screening in TMEM127-related PHEO. Design, Setting, and Participants: Clinical and genetic screening, and genetic counseling were offered to 151 individuals from a six-generation family carrying a TMEM127 germline mutation in a referral center. Intervention and Main Outcome Measures: TMEM127 genetic testing was offered to at-risk relatives and clinical surveillance for pheochromocytoma was performed in mutation-positive carriers. Results: Forty seven individuals carried the c.410-2A>C TMEM127 mutation. Clinical data were obtained from 34 TMEM127-mutation carriers followed up for 8.7 ± 8.1 years (range, 1–20 y). Pheochromocytoma was diagnosed in 11 carriers (32%) at a median age of 43 years. In nine patients, symptoms started at 29 years (range, 10–55 y) and two cases were asymptomatic. Tumors were multicentric in five (45%) and bilateral in five (45%) patients. Six patients (54%) had at least one adrenomedullary nodule less than 10 mm. No paragangliomas, distant metastases, or other manifestations were detected. Cumulative penetrance of pheochromocytoma was 0% at 0–20 years, 3% at 21–30 years, 15% at 31–40 years, 24% at 41–50 years, and 32% at 51–65 years. The youngest case was diagnosed at 22 years and the earliest symptoms were reported at age 10. Conclusions: Tumor multicentricity, nodular adrenomedullary hyperplasia, and the occurrence of symptoms more than a decade earlier than the age at diagnosis are novel findings in TMEM127-related PHEO. The high penetrance of pheochromocytoma in this condition validates the benefits of genetic testing of at-risk relatives. We thus recommend that TMEM127 genetic testing should be offered to at-risk individuals at age 22 years and mutation carriers should undergo clinical surveillance annually.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Objective: To date, no evidence of robust genotype-phenotype correlation or disease modifiers for multiple endocrine neoplasia type 1 (MEN1) syndrome has been described, leaving the highly variable clinical presentation of patients unaccounted for.Design: As the CDKN1B (p27) gene causes MEN4 syndrome and it is transcriptionally regulated by the product of the MEN1 gene (menin), we sought to analyze whether p27 influences the phenotype of MEN1-mutated patients. the cohort consisted of 100 patients carrying germline MEN1 gene mutations and 855 population-matched control individuals.Methods: Genotyping of the coding p27 c.326T>G (V109G) variant was performed by sequencing and restriction site digestion, and the genotypes were associated with clinical parameters by calculating odds ratios (ORs) and their 95% CIs using logistic regression.Results: There were significant differences in p27 V109G allele frequencies between controls and MEN1-mutated patients (OR=2.55, P=0.019, CI=1.013-5.76). Among patients who are >= 30 years old carrying truncating MEN1 mutations, the T allele was strongly associated with susceptibility to tumors in multiple glands (three to four glands affected vs one to two glands affected; OR=18.33; P=0.002, CI=2.88-16.41). This finding remained significant after the Bonferroni's multiple testing correction, indicating a robust association. No correlations were observed with the development of MEN1-related tumors such as hyperparathyroidism, pituitary adenomas, and enteropancreatic and adrenocortical tumors.Conclusions: Our study suggests that the p27 tumor suppressor gene acts as a disease modifier for the MEN1 syndrome associated with MEN1 germline mutations. If confirmed in independent patient cohorts, this finding could facilitate the management of this clinically complex disease. Univ São Paulo, Sch Med, Endocrine Genet Unit, Lab Invest Med LIM 25, São Paulo, Brazil Univ São Paulo, Sch Med, Neuroendocrinol Unit, São Paulo, Brazil Univ São Paulo, Sch Med, Neuroendocrinol Neurosurg Unit, São Paulo, Brazil Univ São Paulo, Sch Med, Adrenal Unit LIM 42, São Paulo, Brazil Univ São Paulo, Sch Med, Gen Endocrinol Unit, São Paulo, Brazil Univ São Paulo, Sch Med, Expt Oncol Lab LIM 24, São Paulo, Brazil Univ São Paulo, Sch Med, Dept Pathol, São Paulo, Brazil Univ São Paulo, Sch Med, Sch Nursing, São Paulo, Brazil Univ São Paulo, Sch Med, Hosp Clin, Sch Publ Hlth, São Paulo, Brazil Brigadeiro Hosp, São Paulo, Brazil Univ São Paulo, Human Genome Res Ctr, São Paulo, Brazil Israelita Ensino & Pesquisa Albert Einstein, Inst Cerebro, São Paulo, Brazil NIA, NIH, Bethesda, MD 20892 USA Helmholtz Zentrum Munchen, Inst Pathol, Neuherberg, Germany Univ São Paulo, Inst Biomed Sci, São Paulo, Brazil Fed Univ São Paulo UNIFESP, Div Endocrinol, São Paulo, Brazil Fed Univ São Paulo UNIFESP, Div Endocrinol, São Paulo, Brazil Web of Science

The Prophet of Pit-1 gene (PROP1) encodes a paired-like homeodomain protein, which is expressed early in pituitary gland development. When mutated, it is responsible for combined pituitary hormone deficiency (CPHD) in humans, as well as in Ames dwarf mice (df/df). Several independent mutations in the homeodomain of PROP1 have been identified as causative for the human CPHD phenotype, which has been characterized, thus far, as absence or low levels of GH, PRL, TSH, LH, and FSH. Here, we report 10 CPHD cases, 9 of which were born to consanguineous marriages occurring in a large family living in an isolated area in the Southeast of Brazil. All affected patients present complete absence of puberty and low GH, PRL, TSH, LH, and FSH associated with severe hypoplasia of the pituitary gland, as seen by MRI. All 3 exons of the PROP1 genes of these patients were sequenced. The 301-302delAG frameshift mutation was found in both alleles of each affected case. Surprisingly, we observed ACTH/cortisol insufficiency associated with the PROP1 phenotype. The patients' ages varied between 8 and 67 yr, and cortisol response impairment was identified in 5 of 6 of the older patients and in an 11-yr-old patient. Previous studies have not fully characterized patients at advanced ages, leading us to conclude that the phenotype of this PROP1 mutation includes late-onset adrenal insufficiency. We present an extensive clinical analysis of all of these patients. The presence of ACTH/cortisol deficiency in this family bearing the PROP1 301-302delAG mutation indicates the importance of a complete endocrine characterization and of life-long monitoring of PROP1 patients.

Introduction: The American Thyroid Association appointed a Task Force of experts to revise the original Medullary Thyroid Carcinoma: Management Guidelines of the American Thyroid Association.

The identification of mutations in the Aryl hydrocarbon receptor interacting protein (AIP) gene in a subset of familial isolated pituitary adenoma (FIPA) cases has recently expanded our understanding of the pathophysiology of inherited pituitary adenoma disorders. However, a genetic cause of has not yet been determined in the majority (85%) of FIPA families and half of the families with isolated familial somatotropinoma. Several studies and reviews have assessed the genetic and clinical features of AIP-mutated FIPA patients, which range from a complete lack of symptoms in adult/elderly individuals to large, aggressive early-onset pituitary tumors. In this study, we aimed to briefly revise the data available for the 11q13 locus and other additional loci that have been implicated in genetic susceptibility to FIPA: 2p16-12; 3q28; 4q32.3-4q33; chr 5, 8q12.1, chr 14, 19q13.4 and 21q22.1. These candidate regions may contain unidentified gene(s) that can be potentially disrupted in AIP-negative FIPA families. A better knowledge of these susceptibility loci may disclose modifier genes that are likely to play exacerbating or protective roles in the phenotypic diversity of AIP-mutated families.

Differences in bone mineral density (BMD) patterns have been recently reported between multiple endocrine neoplasia type 1-related primary hyperparathyroidism (HPT/MEN1) and sporadic primary HPT. However, studies on the early and later outcomes of bone/renal complications in HPT/MEN1 are lacking. In this cross-sectional study, performed in a tertiary academic hospital, 36 patients cases with uncontrolled HPT from 8 unrelated MEN1 families underwent dual-energy X-ray absorptiometry (DXA) scanning of the proximal one-third of the distal radius (1/3DR), femoral neck, total hip, and lumbar spine (LS). The mean age of the patients was 38.9 ± 14.5 years. Parathyroid hormone (PTH)/calcium values were mildly elevated despite an overall high percentage of bone demineralization (77.8%). In the younger group (50 years of age), demineralization in the 1/3DR was more frequent, more severe, and occurred earlier (40%; Z-score -1.81 ± 0.26). The older group (50 years of age) had a higher frequency of bone demineralization at all sites (p .005) and a larger number of affected bone sites (p .0001), and BMD was more severely compromised in the 1/3DR (p = .007) and LS (p = .002). BMD values were lower in symptomatic (88.9%) than in asymptomatic HPT patients (p .006). Patients with long-standing HPT (10 years) and gastrinoma/HPT presented significantly lower 1/3DR BMD values. Urolithiasis occurred earlier (30 years) and more frequently (75%) and was associated with related renal comorbidities (50%) and renal insufficiency in the older group (33%). Bone mineral- and urolithiasis-related renal complications in HPT/MEN1 are early-onset, frequent, extensive, severe, and progressive. These data should be considered in the individualized clinical/surgical management of patients with MEN1-associated HPT.

Previous studies have shown that double RET mutations may be associated with unusual multiple endocrine neoplasia type 2 (MEN 2) phenotypes.Our objective was to report the clinical features of patients harboring a previously unreported double mutation of the RET gene and to characterize this mutation in vitro.Sixteen patients from four unrelated families and harboring the C634Y/Y791F double RET germline mutation were included in the study.Large pheochromocytomas measuring 6.0-14 cm and weighing up to 640 g were identified in the four index cases. Three of the four tumors were bilateral. High penetrance of pheochromocytoma was also seen in the C634Y/Y791F-mutation-positive relatives (seven of nine, 77.7%). Of these, two cases had bilateral tumors, one presented with multifocal tumors, two cases had large tumors (5 cm), and one case, which was diagnosed with a large (5.5 x 4.5 x 4.0 cm) pheochromocytoma, reported early onset of symptoms of the disease (14 yr old). The overall penetrance of pheochromocytoma was 84.6% (11 of 13). Development of medullary thyroid carcinoma in our patients seemed similar to that observed in patients with codon 634 mutations. Haplotype analysis demonstrated that the mutation did not arise from a common ancestor. In vitro studies showed the double C634Y/Y791F RET receptor was significantly more phosphorylated than either activated wild-type receptor or single C634Y and Y791F RET mutants.Our data suggest that the natural history of the novel C634Y/Y791F double mutation carries a codon 634-like pattern of medullary thyroid carcinoma development, is associated with increased susceptibility to unusually large bilateral pheochromocytomas, and is likely more biologically active than each individual mutation.

The identification of mutations in the Aryl hydrocarbon receptor interacting protein (AIP) gene in a subset of familial isolated pituitary adenoma (FIPA) cases has recently expanded our understanding of the pathophysiology of inherited pituitary adenoma disorders. However, a genetic cause of has not yet been determined in the majority (85%) of FIPA families and half of the families with isolated familial somatotropinoma. Several studies and reviews have assessed the genetic and clinical features of AIP-mutated FIPA patients, which range from a complete lack of symptoms in adult/elderly individuals to large, aggressive early-onset pituitary tumors. In this study, we aimed to briefly revise the data available for the 11q13 locus and other additional loci that have been implicated in genetic susceptibility to FIPA: 2p16-12; 3q28; 4q32.3-4q33; chr 5, 8q12.1, chr 14, 19q13.4 and 21q22.1. These candidate regions may contain unidentified gene(s) that can be potentially disrupted in AIP-negative FIPA families. A better knowledge of these susceptibility loci may disclose modifier genes that are likely to play exacerbating or protective roles in the phenotypic diversity of AIP-mutated families.

In 1948, Albright and Reifenstein stated that ‘‘almost all patients with hyperparathyroidism have a marked oliguria immediately following the successful removal of a parathyroid adenoma. In some instances it may be sufficient to cause alarm’’ [1]. This scenario appears to have changed. Today, the risk of hypocalcemia is a great concern after a parathyroid adenoma resection. Some patients are discharged on the day of the operation or on a next-day basis. We have observed, however, that the phenomenon that caused the postoperative course described by Albright and Reifenstein is still occurring, although it is silent in most patients. Notwithstanding, it may cause clinical acute kidney injury, as observed by Laroche et al. [2]. After parathyroidectomy for hyperparathyroidism after renal transplantation, Schwarz et al. correlated the transitory decrease in renal function with a decrease of parathormone (PTH) levels [3]. As PTH reduction is also observed after surgery for primary hyperparathyroidism, we retrospectively analyzed creatinine levels before and during the first 72 h after the operation, when available. A transient increase in creatinine levels above 10% was noted in 77 of 105 cases, and was higher than 50% in 18 cases (17.1%), including one patient that required dialysis [4]. We think that the issue may therefore be of clinical interest. In 38 patients with a preoperative creatinine level less than 1.4 mg/dl (ages varied from 20 to 81 years), it was possible to compare preoperative creatinine levels with the highest levels observed in the first 48 h after the operation. They were significantly increased. The preoperative mean ± standard deviation was 0.84 ± 0.19 mg/dl and, after 48 h, it was 1.13 ± 0.38 mg/dl (p \ 0.0001, Student’s paired test). Astonishingly, in nine patients (23%), the relative increase of creatinine was higher than 50%. Figure 1 illustrates the patterns of creatinine changes observed in these patients. Fortunately, the creatinine levels declined in most patients during the long-term follow-up (they were only slightly elevated when compared to the preoperative levels). Of interest, these observations are in accordance with the effects described by Edvall in 1958 [5]. Perhaps Albright and Reifenstein’s phrase is still valid, but with a small change: ‘‘almost all patients with hyperparathyroidism have a marked creatinine increase immediately following the successful removal of a parathyroid adenoma. In some instances it may be sufficient to cause alarm.’’ Notably, the underlying mechanism of this increase is yet to be explained. We think that until this condition is better understood, nephrotoxic agents or other potential risk factors for kidney injury should be avoided in patients undergoing parathyroidectomy. One may think that the effect here described would be an argument against performing parathyroidectomy in asymptomatic patients. We strongly disagree: parathyroidectomy should be considered very early after the diagnosis, even in asymptomatic cases, before any renal damage caused by hyperparathyroidism ensues. F. Montenegro (&) Department of Head and Neck Surgery, University of Sao Paulo Medical School, Sao Paulo, Brazil e-mail: fabiomonte@uol.com.br

Context: Acromegaly is usually sporadic, but familial cases occur in association with several familial pituitary tumor syndromes. Recently mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene were associated with familial pituitary adenoma predisposition. Objective: The objective of the study was to investigate the status of AIP in a pituitary tumor predisposition family. Settings: The study was conducted at a nonprofit academic center and medical centers. Patients: Eighteen members of a Brazilian family with acromegaly were studied. Results: A novel germline mutation in the AIP gene, Y268X, predicted to generate a protein lacking two conserved domains, was identified in four members of this family: two siblings with early-onset acromegaly; a third, 41-yr-old sibling with a microadenoma but no clinical features of disease, and his 3-yr-old son. No changes were found in 14 unaffected at-risk relatives or 92 healthy controls. Conclusions: We confirm the role of the AIP gene in familial acromegaly. This finding increases the spectrum of molecular defects that can give rise to pituitary adenoma susceptibility. Establishment of genotype-phenotype correlations in AIP mutant tumors will determine whether AIP screening can be used as a tool for clinical surveillance and genetic counseling of families with pituitary tumor predisposition. The underlying basis for the phenotypic variation within AIP-mutant families and the mechanism of AIP-mediated tumorigenesis remain to be defined.

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant inherited tumor syndrome caused by RET proto-oncogene germline mutations (RET). Here we tested the Conformation Sensitive Gel Electrophoresis (CSGE) as a screening method for RET hot-spot mutations. Seven MEN2 families were studied by direct sequencing analysis, CSGE and Single Strand Conformational Polymorphism (SSCP). Using CSGE/SSCP, we were able to detect four out of five types of RET mutations verified by sequencing analysis: Cys620Arg, Cys634Arg, Cys634Tyr, and Met918Thr, furthermore a missense substitution at codon 648 (Val648Ile). RET polymorphisms 691 and 769 were also verified. Data obtained using CSGE/SSCP were fully concordant. We conclude that CSGE showed to be a sensitive, fast, low-cost, and simple procedure to detect RET mutations in codons which are reported as the most prevalent RET variants (~ 95%) in large MEN2 series. As to the Val804Met mutation, this method still needs to be optimized.

OBJECTIVE: Little information is available on glomerular function changes after surgical treatment of primary hyperparathyroidism. The acute effects of some head and neck operations on renal function were studied. MATERIAL AND MATHODS: Retrospective analysis of changes in creatinine levels and estimated glomerular filtration rate (eGFR) after surgery. Preoperative values were compared with values available until 72 hours after the operation. RESULTS: In tertiary hyperparathyroidism, mean preoperative and postoperative eGFR values were 57.7 mL/min and 40.8 mL/min (p < 0.0001), respectively. A similar decrease was observed after parathyroidectomy for primary hyperparathyroidism, from 85.4 mL/min to 64.3 mL/min (p < 0.0001). After major head and neck procedures, there was a slight increase in eGFR (from 94.3 mL/min to 105.4 mL/min, p = 0.002). CONCLUSION: Parathyroidectomy may be followed by a transient decrease in eGFR that is not often observed in other head and neck operations.