Higher SUVmax on FDG-PET is associated with shorter survival in adrenocortical carcinoma

BACKGROUND

Adrenocortical carcinoma (ACC) is an aggressive, rare malignancy. 2-deoxy-2-[18F]-fluoro-d-glucose positron emission tomography (FDG-PET) assesses tumor metabolism and glucose utilization. We hypothesized that higher maximum standard uptake value (SUV_max) is associated with decreased survival.

METHODS

We performed a retrospective analysis of patients with ACC. Included patients (n = 26) had an FDG-PET scan available with a documentable SUV_max. Patients were dichotomized into "High" (≥8.4, n = 12) and "Low" (<8.4, n = 14) SUV_max. Univariate analysis and survival analysis were performed to compare groups.

RESULTS

Demographics between groups were equivalent. The high SUV_max cohort demonstrated lower survival (median 479 days or 15.7 months) compared to the low group (median 1490 days or 48.6 months, p = .01). Log-Rank curve confirmed differences in survival (p = .007).

CONCLUSIONS

Higher SUV_max was associated with significantly worse survival in ACC and may reflect a more aggressive phenotype. FDG-PET may provide clinically useful information to determine prognosis and treatment. Further studies should prospectively evaluate using FDG-PET/CT in ACC.

Evaluating the Rising Incidence of Thyroid Cancer and Thyroid Nodule Detection Modes: A Multinational, Multi-institutional Analysis

Importance

There is epidemiologic evidence that the increasing incidence of thyroid cancer is associated with subclinical disease detection. Evidence for a true increase in thyroid cancer incidence has also been identified. However, a true increase in disease would likely be heralded by an increased incidence of thyroid-referable symptoms in patients presenting with disease.

Objectives

To evaluate whether modes of detection (MODs) used to identify thyroid nodules for surgical removal have changed compared with historic data and to determine if MODs vary by geographic location.

Design, Setting, and Participants

This was a retrospective analysis of pathology and medical records of 1328 patients who underwent thyroid-directed surgery in 16 centers in 4 countries: 4 centers in Canada, 1 in Denmark, 1 in South Africa, and 12 in the US. The participants were the first 100 patients (or the largest number available) at each center who had thyroid surgery in 2019. The MOD of the thyroid finding that required surgery was classified using an updated version of a previously validated tool as endocrine condition, symptomatic thyroid, surveillance, or without thyroid-referable symptoms (asymptomatic). If asymptomatic, the MOD was further classified as clinician screening examination, patient-requested screening, radiologic serendipity, or diagnostic cascade.

Main Outcomes and Measures

The MOD of thyroid nodules that were surgically removed, by geographic variation; and the proportion and size of thyroid cancers discovered in patients without thyroid-referable symptoms compared with symptomatic detection. Data analyses were performed from April 2021 to February 2022.

Results

Of the 1328 patients (mean [SD] age, 52 [15] years; 993 [75%] women; race/ethnicity data were not collected) who underwent thyroid surgery that met inclusion criteria, 34% (448) of the surgeries were for patients with thyroid-related symptoms, 41% (542) for thyroid findings discovered without thyroid-referable symptoms, 14% (184) for endocrine conditions, and 12% (154) for nodules with original MOD unknown (under surveillance). Cancer was detected in 613 (46%) patients; of these, 30% (183 patients) were symptomatic and 51% (310 patients) had no thyroid-referable symptoms. The mean (SD) size of the cancers identified in the symptomatic group was 3.2 (2.1) cm (median [range] cm, 2.6 [0.2-10.5]; 95% CI, 2.91-3.52) and in the asymptomatic group, 2.1 (1.4) cm (median [range] cm, 1.7 [0.05-8.8]; 95% CI, 1.92-2.23). The MOD patterns were significantly different among all participating countries.

Conclusions and Relevance

This retrospective analysis found that most thyroid cancers were discovered in patients who had no thyroid-referable symptoms; on average, these cancers were smaller than symptomatic thyroid cancers. Still, some asymptomatic cancers were large, consistent with historic data. The substantial difference in MOD patterns among the 4 countries suggests extensive variations in practice.

The glass podium: Gender representation within the American Association of Endocrine Surgeons (AAES) from 2010 to 2019

BACKGROUND

Despite increasing numbers of women in surgery, female underrepresentation in surgical societies remains an ongoing issue. We sought to determine the gender composition of presenters at the American Association of Endocrine Surgery annual meetings.

METHODS

Utilizing previous meeting data, we collected gender information for presenters from 2010 to 2019, including first/senior author combinations. Awards winners and invited lecturers were also reviewed. We performed binomial testing to analyze proportions of male to female presenters, with significance set at P < .05. Temporal trends were analyzed via linear regression.

RESULTS

Fifty-six percent of American Association of Endocrine Surgery fellows and 36% of members are female. Of 354 podium and 477 poster presentations, women were listed less often as first (42.7%, P = .007) and senior (30.6%, P < .0001) podium authors and less often as first (42.8%, P = .002) and senior (29.8%, P < .0001) poster authors. The most common combination of first/senior authors was male-male (43.1%), followed by female-male (26.8%), female-female (16.1%), and male-female (14.0%). Less than 15% of invited lecturers were women, and women represented a minority in nearly all award categories. We observed a positive trend in female first authorship over time (slope = 0.766, 95% confidence interval, 0.70%-2.23%, P = .26) but no change in female senior authorship over time (slope = 0.03348, 95% confidence interval, 1.086%-1.153%, P = .95).

CONCLUSION

Women are underrepresented as American Association of Endocrine Surgery presenters and less likely to receive awards or deliver invited lectures. Although female first authorship increased over time, women continued to lag behind men as senior authors and mentors to trainees and junior faculty. Opportunities to improve speaker and awardee representation should be explored.

Practice patterns for surgical management of low-risk papillary thyroid cancer from 2014 to 2019: A CESQIP analysis

BACKGROUND

Patients with low-risk-PTC who undergo thyroid lobectomy (TL) have comparable disease-specific survival with lower morbidity than total thyroidectomy (TT). We aim to describe the surgical management of low-risk-PTC using the Collaborative Endocrine Surgery Quality Improvement Program (CESQIP).

METHOD

CESQIP thyroidectomies of PTC tumors <4 cm were analyzed from 2014 to 2019 (n = 740). Postoperative outcomes were compared. Subgroup analysis examined temporal and institutional trends, and stratified for tumor size. Statistics utilized t-test, ANOVA, and Chi-squared.

RESULTS

TT patients had greater hypoparathyroidism, operative time, and length-of-stay (all p < 0.001). Incidence of TL decreased with increasing tumor size (24.2% for <1 cm, 15.8% for 1-2 cm, 6.1% for 2-4 cm). TL rates increased from 2.0% in 2014 to 21.2% in 2018-19. Completion thyroidectomy was recommended in 12.0% of TL subjects. There was significant variation in TL rate by institution (p < .001).

CONCLUSIONS

For low-risk-PTC, TT remained the most commonly utilized operation. TL rates increased following release of the new ATA guidelines. TT was associated with higher perioperative morbidity. Further insight is needed to understand factors influencing operative approach.

Primary aldosteronism

Primary aldosteronism (PA) is a common cause of secondary hypertension caused by excessive and inappropriate secretion of the hormone aldosterone from one or both adrenal glands. The prevalence of PA ranges from 10% in the general hypertensive population to 20% in resistant hypertension, yet only a small fraction of patients is diagnosed. Disease and symptom recognition, screening in indicated populations, multidisciplinary communication, and appropriate imaging and biochemical workup can identify patients who might benefit from effective and targeted treatment modalities. Effective treatments available include both surgical and medical approaches, usually dependent on the subtype of PA present. Our collective understanding of the pathophysiology of PA is expanded by recent developments in molecular biology and genetics, including understanding the specific somatic and germline mutations involved in pathogenesis. We review the pathophysiology, diagnostic workup, and treatment considerations for this disease process.

Avian lungs: A novel scaffold for lung bioengineering

Allogeneic lung transplant is limited both by the shortage of available donor lungs and by the lack of suitable long-term lung assist devices to bridge patients to lung transplantation. Avian lungs have different structure and mechanics resulting in more efficient gas exchange than mammalian lungs. Decellularized avian lungs, recellularized with human lung cells, could therefore provide a powerful novel gas exchange unit for potential use in pulmonary therapeutics. To initially assess this in both small and large avian lung models, chicken (Gallus gallus domesticus) and emu (Dromaius novaehollandiae) lungs were decellularized using modifications of a detergent-based protocol, previously utilized with mammalian lungs. Light and electron microscopy, vascular and airway resistance, quantitation and gel analyses of residual DNA, and immunohistochemical and mass spectrometric analyses of remaining extracellular matrix (ECM) proteins demonstrated maintenance of lung structure, minimal residual DNA, and retention of major ECM proteins in the decellularized scaffolds. Seeding with human bronchial epithelial cells, human pulmonary vascular endothelial cells, human mesenchymal stromal cells, and human lung fibroblasts demonstrated initial cell attachment on decellularized avian lungs and growth over a 7-day period. These initial studies demonstrate that decellularized avian lungs may be a feasible approach for generating functional lung tissue for clinical therapeutics.

Increased risk organ transplantation in the pediatric population

IRD organs are classified by the Public Health Service to be at above-average risk for harboring human immunodeficiency virus, hepatitis C, and hepatitis B. Traditionally underutilized, there exists even greater reluctance for their use in pediatric patients. We performed a retrospective analysis via the United Network for Organ Sharing database of all pediatric renal and hepatic transplants performed from 2004 to 2008 in the United States. Primary outcomes were patient and graft survival. Proportional hazards regression was performed to control for potentially confounding factors. Waitlist time, organ acceptance rates, and infectious transmissions were analyzed. There were 1830 SRD renal, 92 IRD renal, 1695 SRD hepatic, and 59 IRD hepatic transplants. There were no statistically significant differences in allograft or patient survival in either group. Acceptance rates of IRD organs were lower for kidney (1.5% IRD vs 4.82% SRD) and liver (1.99% IRD vs 4.51% SRD). One transmission of a bloodborne pathogen involving a pediatric recipient out of 7797 unique transplants was reported from 2008 to 2015. IRD organs appear to have equivalent outcomes. Increasing their utilization may improve access to transplant while decreasing wait times and circumventing waitlist morbidity and mortality.

Acute large bowel pseudo-obstruction due to atrophic visceral myopathy: A case report

PURPOSE

Atrophic visceral myopathy is a pathological diagnosis characterized by atrophy of the smooth muscle layers of the viscera with intact ganglia. Rarely, it can present acutely as an intestinal pseudo-obstruction. We describe a rare case report and explore how this diagnosis can be distinguished from other forms of intestinal obstruction.

CASE DESCRIPTION

A 60-year-old male with a past medical history of hypothyroidism presented to the emergency department with a two-day history of worsening abdominal distention and pain associated with nausea and vomiting. Upon evaluation patient was found to have tachycardia, with abdominal distention and localized tenderness with peritonitis. Computed tomography demonstrated large bowel obstruction, likely caused by sigmoid volvulus. The patient underwent emergent laparotomy. Intra-operatively, the entire colon was found to be extremely dilated and redundant. With a working diagnosis of recurrent sigmoid volvulus causing intermittent large bowel obstruction, a sigmoid colectomy and primary anastomosis was performed. Pathology revealed atrophic visceral myopathy, with an extremely thin colonic wall and atrophic circumferential and longitudinal muscularis propria without inflammation or fibrosis. The ganglion cells and myenteric plexus were unaffected. Post-operatively, the patient developed prolonged ileus requiring nasogastric decompression and parenteral nutrition. The ileus resolved with pro-kinetic agents, and patient was discharged home on post-operative day fifteen.

CONCLUSIONS

Atrophic visceral neuropathy is a rare cause of intestinal pseudo-obstruction. While often presenting with chronic obstruction in younger populations, we present a rare late-onset acute presentation that may have been secondary to underlying hypothyroidism.

Cycloheximide impairs and enhances memory depending on dose and footshock intensity

This experiment examined the effects on memory of interactions of cycloheximide dose and training foot shock intensity. Mice received injections of cycloheximide (120 mg/kg, s.c.) or saline 30 min prior to inhibitory avoidance training with shock intensities of 100, 150, 250 or 300 μA (1 s duration). Memory was tested 48 h later. The saline control mice showed increasing memory latencies as a function of shock intensity. The ability of cycloheximide to impair memory increased as the training shock intensity increased. In a second experiment, mice were trained with a 200 μA (1 s duration) shock and received injections of saline or cycloheximide at one of several doses (30, 60 or 120 mg/kg). Under these training conditions, cycloheximide enhanced memory in an inverted-U dose-response manner. These findings are consistent with prior findings suggesting that protein synthesis inhibitors act on memory by altering modulators of memory formation as a secondary consequence of the inhibition of protein synthesis rather than by interfering with training-initiated synthesis of proteins required for memory formation.

Hypercholesterolemia in the rabbit induced by feeding graded amounts of low-level cholesterol. Methodological considerations regarding individual variability in response to dietary cholesterol and development of lesion type

While a number of studies have presented detailed examinations of lesion development in the cholesterol-fed rabbit, individual variability in response to cholesterol feeding and type of lesion produced relative to the degree of cholesterol exposure is not well defined. This study analyzed such critical parameters in an attempt to further characterize the model and establish a baseline for future testing of treatments targeted at limiting atherosclerosis. For these experiments, male New Zealand White rabbits were fed atherogenic diets consisting of 0.05%, 0.10%, 0.15%, 0.20%, or 0.25% cholesterol dissolved in 6% peanut oil for 31 to 32 weeks. Raising dietary cholesterol from 0.05% to 0.15% resulted in a less than twofold stepwise increase in total plasma cholesterol (TPC) exposure (area under plasma cholesterol versus time curve), whereas further increases in cholesterol intake resulted in an exponential four- to fivefold increase in TPC exposure. Regression analysis of TPC exposure with aortic sudanophilia demonstrated a threshold of approximately 5000 cholesterol weeks; below this limit lesions were minimal, and above this value the degree of plaque correlated with TPC exposure. Furthermore, a wide biological variability occurred among rabbits with respect to individual responsiveness to dietary cholesterol. In the aorta, various types of plaques, from fatty streaks to atheromatous lesions, were observed, depending on the degree of cholesterol intake. Diets consisting of < 0.15% cholesterol resulted in the development of fatty streak lesions, while transitional lesions and atheromatous plaques were mostly found with higher cholesterol feeding. Coronary artery atherosclerosis was present in > 50% of animals fed diets > or = 0.15% cholesterol. Despite the level of TPC exposure, coronary lesions in epicardial vessels were generally the fibrous type, whereas intramyocardial arteries demonstrated predominantly intimal foam cells. In conclusion, by adjusting dietary cholesterol intake and selecting rabbits with a similar responsiveness to cholesterol, the overall cholesterol exposure can be more closely controlled to minimize the inherent individual variability among animals in this model. The nature of the target lesion must also be carefully considered, because the efficacy of some treatments may depend on the type of atherosclerotic plaque.

ACAT inhibitors CL 283,546 and CL 283,796 reduce LDL cholesterol without affecting cholesterol absorption in African green monkeys

Previous studies with a number of selective acylcoenzyme A:cholesterol acyltransferase (ACAT) inhibitors in several animal models have demonstrated significant reductions in plasma cholesterol and, in some studies, triglyceride levels. This study was conducted to examine the effects of two ACAT inhibitors, CL 283,546 and CL 283,796, in cholesterol-high fat diet fed African green monkeys, a relevant primate model of hyperlipidemia and coronary artery atherosclerosis. Treatment with CL 283,546 or CL 283,796 resulted in significant reductions (ca. 25-30%) in total plasma cholesterol at both 10 and 30 mg/kg per day doses. This reduction in plasma cholesterol was due almost entirely to reduction in low density lipoprotein (LDL) cholesterol (ca. 45%) without significantly affecting high density lipoprotein (HDL) cholesterol, very low density lipoprotein + intermediate density lipoprotein (VLDL + IDL) cholesterol, or triglyceride concentrations. There were no significant effects on plasma concentrations of apolipoproteins A-I, E, or B and, thus, the reduction seen in LDL cholesterol appears to be due to a diminished cholesterol content of LDL particles. Our studies revealed that treatment with these compounds did not reduce cholesterol absorption, which was somewhat surprising as ACAT inhibitors are generally thought to exert their hypolipidemic effects, at least in part, by inhibition of intestinal cholesterol absorption. Our data are consistent with a principal activity of these drugs on the liver to reduce cholesteryl ester secretion in VLDL, leading to a diminished LDL-cholesterol content, and, presumably, enhanced biliary cholesterol-bile acid excretion.

Characterization of the purine-reactive site of the rat testis cytosolic adenylate cyclase

Naturally soluble rat germ cell adenylate cyclase was inhibited by adenosine and the adenosine analogs, 9-beta-D-arabinofuranosyl adenine (AFA) and 2',5'-dideoxyadenosine (DDA), all of which inhibited hormone-sensitive adenylate cyclases at the "P" site. The IC50 values for adenosine and DDA were approximately 0.1 and for AFA, 4.0 mM. The onset of adenosine inhibition was very rapid whether adenosine was added to the enzyme reactant mixture at time zero concomitantly with the addition of substrate or after the enzyme had been activated by the addition of substrate. The adenosine analogs, N6-methyladenosine (MeA) and N6-phenylisopropyl adenosine (PIA), which interact with plasma membrane receptors ("R" receptors) for hormone-sensitive adenylate cyclase, had little effect on the activity of the cytosolic adenylate cyclase. Additionally, aminophylline, which has been shown to competitively antagonize adenosine interactions with the plasma membrane "R" receptors but not "P" site interactions, had no effect upon substrate activation of the soluble enzyme and did not prevent adenosine from inhibiting the activity of the enzyme. These data provide evidence for an adenosine regulatory site on the cytosolic enzyme which resembles the "P" site described for membrane bound-adenylate cyclase.

Phospholipids inhibit cytotoxic effects of Actinobacillus actinomycetemcomitans leukotoxin on human polymorphonuclear leukocytes

Isolated human peripheral blood neutrophils were exposed to sonic extracts of Actinobacillus actinomycetemcomitans. Such bacterial preparations contain a potent leukotoxin which rapidly kills the leukocytes as reflected by cellular uptake of trypan blue, extracellular release of lactate dehydrogenase, or discharge of 51Cr from pre-labeled cells. Exogenous phospholipids with a glycerol skeleton esterified by fatty acids or positively charged liposomes inhibited cytotoxic phenomena. The data suggest that cell damage may involve the interaction of leukotoxin with phospholipids in the neutrophil cell membrane and that exogenous lipids either compete for or sterically block binding of the leukotoxin to these moieties in the membrane.

Photoaffinity label for the beta-adrenergic receptor: synthesis and effects on isoproterenol-stimulated adenylate cyclase

An azide derivative of the beta-adrenergic antagonist acebutolol has been synthesized and its effect examined on the isoproterenol-stimulated adenylate cyclase [ATP pyrophosphate-lyase (cyclizing); EC 4.6.1.1] activity of rat reticulocytes. It behaved as an effective competitive antagonist (Kd = 2 X 10(-7) M) prior to photolysis. However, when the reticulocyte preparation pretreated with acebutolol azide was photolyzed, a noncompetitive inhibition of isoproterenol-stimulated adenylate cyclase was obtained. Photolysis of the azide derivative in buffer alone did not convert it to a product of higher affnity. Labeling of the beta-adrenergic receptor appeared to be irreversible; multiple washings could not reverse the inhibition produced during photolysis with the label whereas washing would completely reverse the antagonism produced by the same concentration of label prior to photolysis. The effect appears to be specific for the beta-adrenergic receptor because the inhibition could be blocked stereoselectively by propranolol and there was no inhibition of fluoride- or GMP-P(NH)P-stimulated adenylate cyclase. furthermore, no effect was observed on the glucagon-mediated stimulation of adenylate cyclase of liver membranes, whereas the catecholamine response in the same membranes was inhibited.