Update on Pheochromocytoma and Paraganglioma from the SSO Endocrine/Head and Neck Disease-Site Work Group. Part 1 of 2: Advances in Pathogenesis and Diagnosis of Pheochromocytoma and Paraganglioma

This first part of a two-part review of pheochromocytoma and paragangliomas (PPGLs) addresses clinical presentation, diagnosis, management, treatment, and outcomes. In this first part, the epidemiology, prevalence, genetic etiology, clinical presentation, and biochemical and radiologic workup are discussed. In particular, recent advances in the genetics underlying PPGLs and the recommendation for genetic testing of all patients with PPGL are emphasized. Finally, the newer imaging methods for evaluating of PPGLs are discussed and highlighted.

Update on Pheochromocytoma and Paraganglioma from the SSO Endocrine and Head and Neck Disease Site Working Group, Part 2 of 2: Perioperative Management and Outcomes of Pheochromocytoma and Paraganglioma

This is the second part of a two-part review on pheochromocytoma and paragangliomas (PPGLs). In this part, perioperative management, including preoperative preparation, intraoperative, and postoperative interventions are reviewed. Current data on outcomes following resection are presented, including outcomes after cortical-sparing adrenalectomy for bilateral adrenal disease. In addition, pathological features of malignancy, surveillance considerations, and the management of advanced disease are also discussed.

Persistent/Recurrent Primary Hyperparathyroidism: Does the Number of Abnormal Glands Play a Role?

BACKGROUND

Persistent/recurrent hyperparathyroidism occurs in 2%-5% of patients with sporadic primary hyperparathyroidism (PHPT). In this study, the incidence and time to recurrence in patients with single-gland disease (SGD), double adenomas (DAs), or four-gland hyperplasia (FGH) at initial parathyroidectomy were compared.

METHODS

This retrospective review included adult patients with sporadic PHPT who underwent initial parathyroidectomy with intraoperative parathyroid hormone monitoring (IOPTH) from 1/2000 to 12/2016 with ≥6 mo follow-up. An abnormal parathyroid was defined by a gland weight of ≥50 mg. A concurrent serum calcium >10.2 mg/dL and parathyroid hormone >40 pg/mL was defined as persistent PHPT if present <6 mo and recurrent PHPT if present ≥6 mo postoperatively after initial normocalcemia.

RESULTS

Of 1486 patients, 1203 (81%) had SGD, 159 (11%) DA, and 124 (8%) FGH. Among the 3 groups, there was no difference in the percent decrease from the baseline or time of excision to final postexcision IOPTH levels between groups (79% versus 80% versus 80%, respectively; P = 0.954) or in the proportion of patients with a final IOPTH ≥40 (22% versus 18% versus 14%; P = 0.059). Overall, 22 (1.5%) had persistent PHPT and 26 (1.7%) had recurrent PHPT. Persistent PHPT was more frequent with DAs (6; 3.8%) than other groups (SGD: 16, 1.3%; FGH: 0; P = 0.02). At median follow-up of 33 mo (IQR, 18-60), there was no difference in recurrence rate (1.6% versus 2.5% versus 2.4%; P = 0.57) or median time (mo) to recurrence (SGD: 59 [IQR, 21-86], DAs: 36 [IQR, 29-58], FGH: 23 [IQR, 17-40]; P = 0.46).

CONCLUSIONS

Recurrent PHPT occurred in 1.7% of patients who underwent curative initial parathyroidectomy, with no difference in incidence or time to recurrence between groups based on the number of glands removed. Patients with DA more commonly had persistent PHPT, raising the possibility of unrecognized FGH.

Features of synchronous versus metachronous metastasectomy in adrenal cortical carcinoma: Analysis from the US adrenocortical carcinoma database

BACKGROUND

Adrenocortical carcinoma is a rare, aggressive cancer. We compared features of patients who underwent synchronous versus metachronous metastasectomy.

METHODS

Adult patients who underwent resection for metastatic adrenocortical carcinoma from 1993 to 2014 at 13 institutions of the US adrenocortical carcinoma group were analyzed retrospectively. Patients were categorized as synchronous if they underwent metastasectomy at the index adrenalectomy or metachronous if they underwent resection after recurrence of the disease. Factors associated with overall survival were assessed by univariate analysis.

RESULTS

In the study, 84 patients with adrenocortical carcinoma underwent metastasectomy; 26 (31%) were synchronous and 58 (69%) were metachronous. Demographics were similar between groups. The synchronous group had more T4 tumors at the index resection (42 vs 3%, P < .001). The metachronous group had prolonged median survival after the index resection (86.3 vs 17.3 months, P < .001) and metastasectomy (36.9 vs 17.3 months, P = .007). Synchronous patients with R0 resections had improved survival compared to patients with R1/2 resections (P = .008). Margin status at metachronous metastasectomy was not associated with survival (P = .452).

CONCLUSION

Select patients with metastatic adrenocortical carcinoma may benefit from metastasectomy. Patients with metachronous metastasectomy have a more durable survival benefit than those undergoing synchronous metastasectomy. This study highlights need for future studies examining differences in tumor biology that could explain outcome disparities in these distinct patient populations.

Patients with Oncocytic Variant Papillary Thyroid Carcinoma Have a Similar Prognosis to Matched Classical Papillary Thyroid Carcinoma Controls

BACKGROUND

Previous studies have suggested that oncocytic variant papillary thyroid carcinoma (PTC) may be more aggressive, with higher rates of recurrent disease. The aim of this study was to evaluate characteristics and outcomes of patients with oncocytic variant PTC compared to classical PTC.

METHODS

Patients with oncocytic variant PTC were retrospectively identified from 519 patients who underwent thyroidectomy for PTC between January 2009 and August 2015. Data collected included patient demographics, laboratory and pathology findings, imaging studies, treatment, and follow-up. Patients were matched 1:1 by age, sex, and TNM stage with patients who underwent total thyroidectomy for classical PTC during the same time period.

RESULTS

The cohort included 21 patients, of whom 18 (86%) were female, with a median age of 53 years (range 23-68 years). All patients underwent total thyroidectomy, and 17 (81%) had a central compartment neck dissection (8 [38%] prophylactic). The median tumor size was 2.0 cm (range 0.9-6.5 cm), and four (19%) patients had extrathyroidal extension. There was no significant difference in histopathologic characteristics, including extrathyroidal extension and lymphovascular invasion, between the two groups except for an increased incidence of thyroiditis in oncocytic variant PTC (90.5% vs. 57%; p = 0.01). In oncocytic variant PTC patients who underwent central compartment neck dissection, malignant lymph nodes were found in 12 (57%) patients compared to 13 (62%) classical (p = 0.75). Lateral neck dissection was performed in 5 (24%) oncocytic variant and classical PTC patients, with metastatic lymphadenopathy found in four (a median of four malignant lymph nodes; range 1-6) and five (a median of 2.5 malignant lymph nodes; range 1-9), respectively. Radioactive iodine was administered to 18 (86%) oncocytic variant PTC and 18 (86%) classical PTC patients. At a median follow-up of 51 months (interquartile range 38-61), one oncocytic variant PTC patient had recurrent disease and underwent reoperation at 24 months. In classical PTC patients with a median follow-up time of 77 months (range 56-87 months), two (9.5%) patients had detectable thyroglobulin levels indicating early recurrence, but neither has undergone reoperation.

CONCLUSIONS

Oncocytic variant PTC was present in 5% of PTC patients. Most (95%) patients remain disease-free at four years, similar to classical PTC outcomes, suggesting that oncocytic variant may not represent a more aggressive variant.

Thyroid surgery for differentiated thyroid cancer - recent advances and future directions

Population-based studies have demonstrated that an increasing number of incidental thyroid nodules are being identified. The corresponding increase in thyroid-based diagnostic procedures, such as fine-needle aspiration biopsy, has in part led to an increase in the diagnoses of thyroid cancers and to more thyroid surgeries being performed. Small papillary thyroid cancers account for most of this increase in diagnoses. These cancers are considered to be low risk because of the excellent patient outcomes, with a 5-year disease-specific survival of >98%. As a result, controversy remains regarding the optimal management of newly diagnosed differentiated thyroid cancer, as the complications related to thyroidectomy (primarily recurrent laryngeal nerve injury and hypoparathyroidism) have considerable effects on patient quality of life. This Review highlights current debates, including undertaking active surveillance versus thyroid surgery for papillary thyroid microcarcinoma, the extent of thyroid surgery and lymphadenectomy for low-risk differentiated thyroid cancer, and the use of molecular testing to guide decision-making about whether surgery is required and the extent of the initial operation. This Review includes a discussion of current consensus guideline recommendations regarding these topics in patients with differentiated thyroid cancer. Additionally, innovative thyroidectomy techniques (including robotic and transoral approaches) are discussed, with an emphasis on patient preferences around decision-making and outcomes following thyroidectomy.

Continuous Etomidate Infusion for the Management of Severe Cushing Syndrome: Validation of a Standard Protocol

Objective

Demonstrate the safety and efficacy of a standardized intravenous etomidate infusion protocol in normalizing cortisol levels in patients with severe and life-threatening hypercortisolism.

Methods

A retrospective case series of seven patients representing nine episodes of severe hypercortisolism at two large academic medical centers was conducted. Patients were included in this series if they received an etomidate infusion for the treatment of severe and life-threatening hypercortisolism. The etomidate infusion was administered via a newly developed protocol designed to safely reduce cortisol levels until more long-term medical or definitive surgical therapy could be instituted.

Results

Seven patients representing nine episodes received etomidate treatment. In eight of nine episodes of therapy, rapid control of hypercortisolemia was achieved, generally defined as a serum cortisol level of 10 to 20 µg/dL. Patients with a median baseline cortisol of 105 µg/dL (range, 32 to 245 µg/dL) achieved a median nadir serum cortisol of 15.8 µg/dL (range, 6.9 to 27 µg/dL) after a median of 38 hours (range, 26 to 134 hours).

Conclusions

A standardized continuous intravenous etomidate infusion protocol is a safe and effective means of achieving a serum cortisol level of 10 to 20 µg/dL in patients with severe hypercortisolemia.

The prognostic significance of adrenocortical carcinomas identified incidentally

BACKGROUND AND OBJECTIVES

Little is known regarding the difference in prognosis among patients who have an incidentally discovered adrenocortical carcinoma (ACC) vs those who present with signs or symptoms. We aimed to explore differences in the outcomes of these two populations.

METHODS

Data were collected on patients who underwent resection of ACC at 1 of 13 institutions between January 1993 and December 2014. Presentations were categorized as incidental vs symptomatic and outcomes were compared.

RESULTS

Among 227 patients, 100 were diagnosed incidentally while 127 patients presented with symptoms/signs. Clinical and pathological features were comparable among incidental vs nonincidental patients with ACC following the exceptions. Patients with incidentalomas were more likely to have a T1/T2 tumor (55.8% vs 34.8%; P < 0.01) and less likely to have a functional tumor (33.7% vs 47.9%; P = 0.04). Patients with an incidental ACC had improved median recurrence-free survival (RFS; 29.4 months) compared with patients with a nonincidental ACC (13.0 months; P = 0.03); however, on multivariable analysis, incidental ACC was not an independent predictor of survival.

CONCLUSIONS

Patients with resected ACC identified incidentally had an improved RFS compared with the patients who presented with symptoms or signs. This difference may be related to the patients with incidental tumors having earlier T-stage disease.

Molecular evaluation of a sporadic paraganglioma with concurrent IDH1 and ATRX mutations

PURPOSE

Pheochromocytomas and paragangliomas (PPGLs) are neuroendocrine tumors of neural crest origin. Germline or somatic mutations of numerous genes have been implicated in the pathogenesis of PPGLs, including the isocitrate dehydrogenase 1 (IDH1) gene and alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene. Although concurrent IDH1 and ATRX mutations are frequently seen in gliomas, they have never been reported together in PPGLs. The aim of this study was to characterize one paraganglioma with concurrent IDH1 and ATRX mutations identified by whole exome sequencing.

METHODS

Leukocyte and tumor DNA were used for whole exome sequencing and Sanger sequencing. 2-hydroxyglurarate level and the global DNA methylation status in the tumor were measured. ATRX's cDNA transcripts were analyzed. Tyrosine hydroxylase (TH), HIF1α and ATRX staining, as well as telomere-specific FISH was also performed.

RESULTS

The presence of a somatic IDH1 (c.394C>T, p.R132C) mutation and a concurrent somatic ATRX splicing mutation (c.4318-2A>G) in the current case was confirmed. Dramatic accumulation of 2-hydroxyglutarate was detected in the paraganglioma without the global DNA hypermethylation, and pseudohypoxia was also activated. Importantly, immunohistochemistry revealed negative TH staining in the tumor and the first exon region of TH gene was hypermethylated resulting in normal plasma metanephrines. The splicing ATRX mutation resulted in two transcripts, causing frameshifts. Immunohistochemistry revealed scarce ATRX staining in the tumor. Alternative lengthening of telomeres (ALT) was detected by FISH.

CONCLUSIONS

This case represents the first concurrence of IDH1 and ATRX mutations in PPGLs. Although relatively rare, a somatic R132C mutation of IDH1 might play a role in a small subset of sporadic PPGLs.

Effect of pH on uranium(VI) biosorption and biomineralization by Saccharomyces cerevisiae

Biosorption of radionuclides by microorganisms is a promising and effective method for the remediation of contaminated areas. pH is the most important factor during uranium biosorption by Saccharomyces cerevisiae because the pH value not only affects the biosorption rate but also affects the precipitation structure. This study investigated the effect of pH on uranium (VI) biosorption and biomineralization by S. cerevisiae. Cells have the ability to buffer the solution to neutral, allowing the biosorption system to reach an optimal level regardless of the initial pH value. This occurs because there is a release of phosphate and ammonium ions during the interaction between cells and uranium. The uranyl and phosphate ions formed nano-particles, which is chernikovite H₂(UO₂)₂(PO₄)₂·8H₂O (PDF #08-0296), on cell surface under the initial acidic conditions. However, under the initial alkaline conditions, the uranyl, phosphate and ammonium ions formed a large amount of scale-like precipitation, which is uramphite (NH₄)(UO₂)PO₄·3H₂O (PDF #42-0384), evenly over on cell surface.

Role of Additional Organ Resection in Adrenocortical Carcinoma: Analysis of 167 Patients from the U.S. Adrenocortical Carcinoma Database

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare and aggressive cancer. This report describes factors and outcomes associated with resection of extra-adrenal organs en bloc during index adrenalectomy.

METHODS

Patients who underwent ACC resection for non-metastatic disease from 1993 to 2014 at 13 participating institutions of the US-ACC Group were included in the study. Factors associated with en bloc resection were assessed by uni- and multivariate analysis. The primary end point was overall survival.

RESULTS

In this study, 167 patients were included and categorized as adrenalectomy with en bloc resection (AdEBR) if they had extra-adrenal organs removed or adrenalectomy (Ad) if they did not. The demographics were similar between the AdEBR (n = 68, 40.7%) and Ad groups, including age, gender, race, American Society of Anesthesiology (ASA) class, and body mass index (BMI). The AdEBR group had larger tumors (13 vs. 10 cm), more open operations (97.1 vs. 63.6%), and more lymph node dissections (LNDs) (36.8 vs. 12.1%). The most common organs removed were kidney (55.9%), liver (27.9%), and spleen (23.5%). Multiple organs were removed in 38.2% (n = 26) of the patients. Margin-negative resections were similar between the two groups. In the multivariate Cox regression adjusted for T and N stages, LND, margin, size, and hormone hypersecretion, en bloc resection was not associated with improved survival (hazard ratio [HR], 1.42; p = 0.323).

CONCLUSION

The study findings validated current practice by showing that en bloc resection should occur at index adrenalectomy for ACC when a T4 lesion is suspected pre- or intraoperatively, or when it is necessary to avoid tumor rupture. However, in this study, when a negative margin resection was otherwise achieved, removal of extra-adrenal organs en bloc was not associated with additional survival benefit.

Absence of single critical dose for the amorphization of quartz under ion irradiation

In this work, we first simulated the amorphization of crystalline quartz under 50 keV [Formula: see text]Na ion irradiation with classical molecular dynamics (MD). We then used binary collision approximation algorithms to simulate the Rutherford backscattering spectrometry in channeling conditions (RBS-C) from these irradiated MD cells, and compared the RBS-C spectra with experiments. The simulated RBS-C results show an agreement with experiments in the evolution of amorphization as a function of dose, showing what appears to be (by this measure) full amorphization at about 2.2 eV⋅[Formula: see text]. We also applied other analysis methods, such as angular structure factor, Wigner-Seitz, coordination analysis and topological analysis, to analyze the structural evolution of the irradiated MD cells. The results show that the atomic-level structure of the sample keeps evolving after the RBS signal has saturated, until the dose of about 5 eV⋅[Formula: see text]. The continued evolution of the [Formula: see text] structure makes the definition of what is, on the atomic level, an amorphized quartz ambiguous.

The role and timing of parathyroid hormone determination after total thyroidectomy

Postoperative hypocalcemia is a common complication of total thyroidectomy resulting from manipulation, resection, or devascularization of the parathyroid glands. Parathyroid hormone (PTH) levels assessed in the perioperative period have been used to predict development of hypocalcemia. Articles examining the role of PTH measurement in the perioperative period following total or completion thyroidectomy are reviewed. Focus is placed on the timing of PTH measurement and the ability to predict which patients will develop hypocalcemia requiring supplementation. Postoperative PTH determination is highly accurate in predicting the development of hypocalcemia. Studies have examined PTH levels drawn at differing time points, ranging from intraoperatively until postoperative day 1 (POD1) with similar accuracy. This data is used to guide postoperative selective calcium and calcitriol supplementation in patients at highest risk for hypocalcemia. When evaluated within the first 4 hours postoperatively, predictive accuracy is maintained but can allow for earlier discharge for those patients at lower risk. Alternatively, some authors argue for routine supplementation, which can reduce the rate of postoperative hypocalcemia but increases the rate of unnecessary supplementation and potential risks associated with hypercalcemia. PTH determination at four hours after total thyroidectomy is an accurate predictor of hypocalcemia and can guide selective calcium supplementation for those at high risk, as well as facilitate a safe earlier hospital discharge for those at low risk of developing postoperative hypocalcemia.