Citations

AbstractMagnetic resonance elastography (MRE) is an accurate noninvasive diagnostic tool for assessing the stiffness of parenchymal organs, including the spleen. However, this measurement may be biased due to postprandial changes in splenic stiffness. The aim of the current study was to evaluate postprandial changes in spleen stiffness assessed by MRE in a large sample of healthy volunteers. This was a prospective institutional research ethics board‐approved study. Healthy volunteers with no history of liver disease were recruited for an MRE test and blood draw from December 2018 to July 2019. Each participant underwent spleen MRE after at least 4 h of fasting and again 30 min after a 1000 kcal meal. Also, 14 randomly selected volunteers underwent additional MRE examinations at 1.5 and 2.5 h after food intake. The MRE data were acquired at 60 Hz using a 1.5‐T MRI scanner. The spleen stiffness was assessed using a weighted mean of stiffness values from regions of interest manually drawn on three to five spleen slices. Spearman's rank correlation, Wilcoxon signed‐rank, Friedman, and Mann–Whitney tests were used for statistical analysis. A total of 100 volunteers met the inclusion criteria and were eventually enrolled in this study (age 23 ± 2 years; 65 women). The mean spleen stiffness for the whole group increased by 7.9% (p < 0.001) from the mean ± SD value of 5.09 ± 0.63 (95% CI: 4.96–5.21) kPa in the fasting state to 5.47 ± 0.66 (95% CI 5.34–5.60) kPa 30 min after the meal and then gradually decreased. However, even 2 h 30 min after the meal, the spleen stiffness was higher than in the fasting state. This difference was statistically significant at p less than 0.001. It was concluded that meal intake results in a statistically significant elevation of spleen stiffness that persists for 2.5 h. This finding supports the recommendation for routine fasting for more than 2.5 h prior to assessing MRE‐based spleen stiffness.

Abstract Disclosure: O.A. Shariq: None. T.J. McKenzie: None. W.F. Young: None. Background: Multiple endocrine neoplasia type 2B (MEN2B) is most commonly caused by a germline methionine-to-threonine substitution at codon 918 (M918T) of the RET proto-oncogene. The syndrome is characterized by medullary thyroid carcinoma, pheochromocytoma, and extra-endocrine manifestations (intestinal ganglioneuromas, mucosal neuromas, and skeletal and ophthalmic abnormalities). We describe a patient with MEN2B and bilateral pheochromocytomas, in whom the slow-growing nature of the lesions, and previous history of an extra-endocrine manifestation, precluded the typical approach to surgical resection. Clinical Case: A 58-year-old-male with MEN2B, diagnosed at age 15, presented with a 6-month history of episodic palpitations and labile blood pressures. His past surgical history included a total abdominal colectomy and ileorectal anastomosis at age 7 years for megacolon, secondary to intestinal ganglioneuromatosis. He subsequently required multiple laparotomies and adhesiolysis procedures for recurrent small bowel obstructions. During his most recent laparotomy at age 44, he was noted to have a ‘frozen’ abdomen with dense adhesions involving the small bowel. CT abdomen revealed bilateral adrenal masses, measuring 2.9 cm and 1.5 cm on the right and left, respectively. Review of previous imaging revealed that the right adrenal mass had been present 16 years prior, measuring 1.0 cm at that time, while the left-sided mass was not seen. Biochemical workup was negative previously, but now showed elevated plasma metanephrine (4.1 nmol/L [N&lt;0.5 nmol/L ]) and normetanephrine 2.3 nmol/L [N&lt;0.9 nmol/L ]) levels. In the setting of extensive intra-abdominal adhesions and the slow-growing nature of both masses, the decision was made to perform a unilateral right adrenalectomy through a retroperitoneoscopic, rather than a transabdominal, approach. Pathology confirmed a 4.4 cm pheochromocytoma. The patient was discharged on postoperative day 1 and was symptom free at 1 year follow-up. His most recent plasma metanephrine and normetanephine levels were 0.7 nmol/L and 0.5 nmol/L, respectively. Clinical Lessons: Patients with MEN2B have a 50% lifetime risk of developing pheochromocytoma. Unlike medullary thyroid cancer, which exhibits an aggressive phenotype in this syndrome, MEN2B-associated pheochromocytomas may be slow growing, thereby avoiding the need for an initial bilateral adrenalectomy. Many patients with MEN2B develop gastrointestinal manifestations, including megacolon during infancy, for which multiple surgical interventions may be required. These procedures carry a risk of adhesion formation, which presents a challenge if further abdominal surgery is required later in life for pheochromocytoma. Retroperitoneoscopic adrenalectomy provides a safe approach in such patients, as the need to perform risky adhesiolysis and mobilize adjacent organs is obviated. Presentation: Saturday, June 17, 2023

Abstract Disclosure: S.A. Jacob: None. M. Itani: None. M.J. Hoegger: None. D. Ludwig: None. T. Pandian: None. T.C. Brown: None. L.M. Brunt: None. I. Bancos: None. N. Genere: None. Introduction: Adrenal mass incidence has increased tenfold over the last two decades, with most masses detected in individuals over 40 years of age. The majority of these adrenal masses are benign (&gt;80%), and few are malignant (8%) or hormonally active (4%); most are incidentally detected. Studies suggest higher rates of hormonally active and malignant adrenal masses in younger patients, however, evidence for this age group is scarce. In two recent large cohort studies of adrenal masses, young adults (18-40 years) represented only 0.2-7.1% of individuals studied. This study aimed to characterize clinical, imaging, and biochemical presentation of young adults diagnosed with adrenal masses. Methods: This is a retrospective cohort study of young adults (18-40 years) with adrenal masses detected based on a radiology report text database search between January 2015 and December 2021 at a tertiary medical center. Exclusion criteria included pre-existing adrenal masses before 2015, hyperplasia, or masses &lt;1cm. Images were reviewed by abdominal radiologists, and clinical data were obtained through review of electronic medical records. Results: A total of 255 young adults (56% women, 61% white) were diagnosed with adrenal masses with median age 35 (IQR 30-39) years. Genetic predisposition syndrome was present in 6%. Comorbidities included: BMI &gt;30 kg/m2 in 48%, hypertension in 35%, and diabetes in 10%. Adrenal masses were detected incidentally in 72% and during cancer staging in 16%. Median mass size was 1.9cm (IQR 1.4-2.7cm) and 49% (39/79) were lipid poor (Hounsfield units &gt;10). Only 22% of patients underwent hormonal evaluation. Final diagnoses included 16% malignancy, 9% benign adenoma with overt hormone excess, 40% benign adenoma with incomplete hormonal evaluation and 24% radiographically indeterminate masses. Subgroup analysis showed that adrenal masses in those &lt;30 years old compared to 31-40 year-olds were more frequently associated with tumor predisposition syndrome (15% vs 3%, p&lt;0.01) and more often lipid poor (76% vs 40%, p&lt;0.01); but, no differences in frequency of malignancy or overt hormone excess were identified. Discussion: We found a higher frequency of malignancy and overt hormonal excess in our cohort of young adults compared to previously published studies, though direct comparisons are limited by differences in methodology. These findings, in addition to high frequencies of metabolic disease in our cohort, would suggest the need for hormonal assessment in young adults; yet, this was completed in only a minority of patients. Additional areas of research may include studying hormonal status of adrenal masses in young adults in a multi-center cohort to overcome issues of selection bias and increase the rates of those with complete hormonal evaluation. Presentation: Thursday, June 15, 2023

Abstract Disclosure: A. Blinder: None. K. Nanba: None. D. Sapiro: None. J. Baker: None. C. Liu: None. I. Bancos: None. M. Lyden: None. W. Young: None. H. Wachtel: None. D. Cohen: None. J. Luther: None. T.A. Williams: None. M. Reincke: None. T. Else: None. T.J. Giordano: None. A. Udager: None. W.E. Rainey: None. Background: There is accumulating evidence that changes in adrenal histology and regulation of renin-angiotensin-aldosterone system occur with age. Primary aldosteronism (PA) is the most common cause of endocrine hypertension. Recent clinical studies suggest unique characteristics of PA in elderly patients, including high prevalence of comorbidities and low clinical cure rate after adrenalectomy. However, histologic and genetic features of PA in late adulthood have not been well elucidated. Objective: To determine histologic and genetic characteristics of PA in late adulthood. Methods: Seventy-six patients who underwent unilateral adrenalectomy at the age of 60 or older were included in this study. Formalin-fixed, paraffin-embedded (FFPE) sections of resected adrenal tissue were used for the analysis. Aldosterone synthase (CYP11B2) immunohistochemistry (IHC) was performed to identify the source of inappropriate aldosterone production. Histologic classification was made according to the HISTALDO (histopathology of primary aldosteronism) consensus. CYP11B2 IHC-guided DNA capture followed by sequencing analysis using direct Sanger sequencing or ion torrent based next-generation sequencing (NGS) was performed. Results: Median age of the studied patients was 70 (interquartile range: 64-73). Based on the CYP11B2 IHC, histologic diagnosis was made as follows; aldosterone-producing adenoma (APA, n=23), aldosterone-producing nodule (APN, n=41), and non-functioning adrenocortical adenoma (NFA, n=6). The remaining six cases had multiple CYP11B2-expressing neoplastic lesions, including APA with APN (n=2) and multiple APNs (n=4). Co-existence of NFA with APA or APN(s) was also observed in 13. Sequencing analysis revealed that somatic KCNJ5 mutation was the most frequent genetic alteration in APA (7/23, 30%), whereas somatic CACNA1D mutation was the most common genetic cause of APN (20/39 with successful sequencing, 51%). Of the 18 sequenced NFA DNA samples, two had somatic mutations in CTNNB1 (n=1) and GNAS (n=1). Conclusion: APN is the major histologic feature of PA in late adulthood. Co-existence of NFA also appears to be a frequent observation in this age population. Somatic CACNA1D and KCNJ5 mutations are common in APN and APA, respectively. Presentation: Friday, June 16, 2023

Abstract Disclosure: S. Rolak: None. N. Venkatesan: None. R. Gregg Garcia: None. W.F. Young: None. I. Bancos: None. Background: Bilateral primary hyperaldosteronism (PA) is treated with mineralocorticoid receptor antagonist (MRA) therapy. However, the best way to monitor the success of MRA therapy is unclear. Aims: To compare the impact of curative adrenalectomy versus MRA therapy in patients with PA on plasma renin activity (PRA), renal function, and hypertension control. Methods: Single center retrospective study of patients with unilateral PA treated with adrenalectomy or bilateral PA treated with MRAs, 2017-2021. Patients underwent adrenal vein sampling to confirm laterality. Hypertension control was defined based on blood pressure measurements and the standardized hypertension daily dose (HDD). Minimum follow-up was defined as first nonsuppressed PRA or &gt;1 month from therapy. Results: Of 73 patients, 53 underwent unilateral adrenalectomy for unilateral PA (median age 57, range 25-71 years, 36% women) and 20 had bilateral PA treated with MRA (median age 49, range 30-70 years, 70% women). At baseline, when compared to the bilateral PA, patients with unilateral PA had higher plasma aldosterone concentrations (median 31 ng/dL vs 19 ng/dL, P= 0.001), similarly suppressed PRA, and similar estimated glomerular filtration rate (eGFR). Uncontrolled hypertension (&gt;130/90 mmHg) was seen in 40 (75%) of patients with unilateral PA and 14 (70%) patients with bilateral PA, despite a more intensive antihypertensive regimen in unilateral PA (median HDD 5, range 1-18 vs median HDD 3.5 in bilateral PA, range 0.5-9; P=0.016). Hypokalemia was present in 50 (94%) patients with unilateral PA and 15 (75%) in bilateral PA, P = 0.02.Following treatment, hyperkalemia developed in 10 (19%) patients post-adrenalectomy and in 2 (10%) patients treated with MRAs, P = 0.36. At a median follow up of 108 days, 24 (45%) patients treated with adrenalectomy and 16 (80%) patients treated with MRAs demonstrated PRA &gt;1.5 ng/mL/hr, P = 0.008. eGFR decreased by at least 10 points in 15 (30%) patients treated with adrenalectomy vs in 11 (59%) patients treated with MRAs (P=0.033). Post-adrenalectomy, antihypertensive management lessened by a median of 2.5 HDD, while HDD increased in patients treated with MRAs by a median of 1.25, P&lt;0.0001. Hypertension control improved, with a mean decrease in systolic blood pressure of -11 mmHg (95%CI -16.5-(-5.5)) without between group differences. Diastolic blood pressure decreased by a mean of -4.7 mmHg (95%CI -8.7-(-0.7)) in the adrenalectomy group but did not change in those treated with MRAs. Conclusions: Following curative adrenalectomy in unilateral PA, more than half of patients continue to have suppressed PRA. Despite less severe PA at baseline, patients treated with MRAs, as compared to those treated with adrenalectomy, demonstrate a higher prevalence of non-suppressed PRA, lower eGFR, similar hypertension control, and a more intense antihypertensive regimen during follow up. Presentation: Thursday, June 15, 2023

Chronic myeloid leukemia (CML) is usually a disease of the elderly population characterized by a clonal hematopoietic progenitor cell disorder propelled by the product of the breakpoint cluster region-Abelson murine leukemia (BCR-ABL) chimeric gene, known as the Philadelphia chromosome. It occurs due to a balanced reciprocal translocation between the long arms of chromosomes 9 and 22, which codes for tyrosine kinase. The incidence of CML increases with age, and the median age of diagnosis in Western countries is 64 years. The most common finding at presentation is abdominal pain due to splenomegaly which is present in about half of the patients. We present a rare case of CML in the chronic phase where a young 23-year-old male presented with complaints of severe bilateral lower limb bone pain restricting mobility at the hip joint for 1 year. The upper end of the femur showed heterogeneous areas of bone infarct on the technetium 99 m-methylene diphosphonate bone scan. He was treated with imatinib mesylate, and he entered remission within 5 months of starting therapy. This case highlights the atypical presentation of the chronic phase of CML with the e13a2 BCR-ABL fusion transcript in a young patient and the complete recovery achieved with standard therapy.

Abstract Lithium is the gold standard treatment for bipolar disorder (BD). However, its mechanism of action is incompletely understood, and prediction of treatment outcomes is limited. In our previous multi-omics study of the Pharmacogenomics of Bipolar Disorder (PGBD) sample combining transcriptomic and genomic data, we found that focal adhesion, the extracellular matrix (ECM), and PI3K-Akt signaling networks were associated with response to lithium. In this study, we replicated the results of our previous study using network propagation methods in a genome-wide association study of an independent sample of 2,039 patients from the International Consortium on Lithium Genetics (ConLiGen) study. We identified functional enrichment in focal adhesion and PI3K-Akt pathways, but we did not find an association with the ECM pathway. Our results suggest that deficits in the neuronal growth cone and PI3K-Akt signaling, but not in ECM proteins, may influence response to lithium in BD.

Abstract Histone H3 lysine 9 methylation (H3K9me), which is written by the Euchromatic Histone Lysine Methyltransferases EHMT1 and EHMT2 and read by the heterochromatin protein 1 (HP1) chromobox (CBX) protein family, is dysregulated in many types of cancers. Approaches to inhibit regulators of this pathway are currently being evaluated for therapeutic purposes. Thus, knowledge of the complexes supporting the function of these writers and readers during the process of cell proliferation is critical for our understanding of their role in carcinogenesis. Here, we immunopurified each of these proteins and used mass spectrometry to define their associated non-histone proteins, individually and at two different phases of the cell cycle, namely G1/S and G2/M. Our findings identify novel binding proteins for these writers and readers, as well as corroborate known interactors, to show the formation of distinct protein complex networks in a cell cycle phase-specific manner. Furthermore, there is an organizational switch between cell cycle phases for interactions among specific writer–reader pairs. Through a multi-tiered bioinformatics-based approach, we reveal that many interacting proteins exhibit histone mimicry, based on an H3K9-like linear motif. Gene ontology analyses, pathway enrichment, and network reconstruction inferred that these comprehensive EHMT and CBX-associated interacting protein networks participate in various functions, including transcription, DNA repair, splicing, and membrane disassembly. Combined, our data reveals novel complexes that provide insight into key functions of cell cycle-associated epigenomic processes that are highly relevant for better understanding these chromatin-modifying proteins during cell cycle and carcinogenesis.