Loosening the belt on magnetic sphincter augmentation indications: does body mass index matter?

BACKGROUND: Magnetic sphincter augmentation (MSA) is an effective treatment for gastroesophageal reflux disease (GERD). However, the impact of obesity on MSA outcomes is unknown. The objective of this study was to evaluate the effectiveness of MSA in patients with GERD and obesity. METHODS: A retrospective cohort study was performed of consecutive patients who underwent laparoscopic MSA at three high-volume centers from 2016 to 2019. Patients were grouped into four cohorts according to the World Health Organization body mass index (BMI) classification: BMI < 25 (normal weight), BMI 25-29.9 (overweight), BMI 30-34.9 (obese class I), and BMI > 35 (obese class II-III). Preoperative, operative, and postoperative data were compared between groups. RESULTS: A total of 621 patients underwent laparoscopic MSA during the study period. Follow-up with endoscopy or video esophagram was available for 361 patients (58%) with a median follow-up of 15.4 months. Baseline characteristics of the groups were similar except the BMI > 35 group had more females and a higher preoperative median DeMeester score. There were no significant differences in outcomes between normal weight, overweight, and obese patient groups undergoing MSA. All groups experienced significant reductions in acid suppressive medication use, low GERD-HRQL scores, low DeMeester scores, few intraoperative and postoperative complications, and low rates of hiatal hernia recurrence after MSA. CONCLUSIONS: Magnetic sphincter augmentation is safe and effective in improving GERD symptoms, reducing esophageal acid exposure, and preventing hiatal hernia recurrence, irrespective of patient BMI. MSA should be considered an acceptable treatment option for obese patients with GERD.

Parathyroid conditions in childhood.

This review of parathyroid surgery in children will briefly discuss parathyroid gland embryology and anatomy before focusing on the pathophysiology, clinical presentation, and treatment of hyperparathyroidism in children. Hyperparathyroidism (HPT) is the overproduction of PTH and it is rare in children, with an incidence of 2-5 per 100,000. This rarity means that the principles of caring for children with parathyroid disease are largely extrapolated from the richer adult experience; however, the unique pediatric aspects of parathyroid problems and their surgical treatment, including presentation, imaging, operative approach, and complications, will be considered.

MK-2206 causes growth suppression and reduces neuroendocrine tumor marker production in medullary thyroid cancer through Akt inhibition.

BACKGROUND: Development of targeted therapies for medullary thyroid cancer (MTC) has focused on inhibition of the rearranged during transfection (RET) proto-oncogene. Akt has been demonstrated to be a downstream target of RET via the key mediator phosphoinositide-3-kinase. MK-2206 is an orally administered allosteric Akt inhibitor that has exhibited minimal toxicity in phase I trials. We explored the antitumor effects of this compound in MTC. METHODS: Human MTC-TT cells were treated with MK-2206 (0-20 µM) for 8 days. Assays for cell viability were performed at multiple time points with MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). The mechanism of action, mechanism of growth inhibition, and production of neuroendocrine tumor markers were assessed with Western blot analysis. RESULTS: MK-2206 suppressed MTC cell proliferation in a dose-dependent manner (p ≤ 0.001). Levels of Akt phosphorylated at serine 473 declined with increasing doses of MK-2206, indicating successful Akt inhibition. The apoptotic proteins cleaved poly (ADP-ribose) polymerase and cleaved caspase-3 increased in a dose-dependent manner with MK-2206, while the apoptosis inhibitor survivin was markedly reduced. Importantly, the antitumor effects of MK-2206 were independent of RET inhibition, as the levels of RET protein were not blocked. CONCLUSIONS: MK-2206 significantly suppresses MTC proliferation without RET inhibition. Given its high oral bioavailability and low toxicity profile, phase II studies with this drug alone or in combination with RET inhibitors are warranted.

Octreotide-functionalized and resveratrol-loaded unimolecular micelles for targeted neuroendocrine cancer therapy.

Medullary thyroid cancer (MTC) is a neuroendocrine tumor (NET) that is often resistant to standard therapies. Resveratrol suppresses MTC growth in vitro, but it has low bioavailability in vivo due to its poor water solubility and rapid metabolic breakdown, as well as lack of tumor-targeting ability. A novel unimolecular micelle based on a hyperbranched amphiphilic block copolymer was designed, synthesized, and characterized for NET-targeted delivery. The hyperbranched amphiphilic block copolymer consisted of a dendritic Boltorn® H40 core, a hydrophobic poly(l-lactide) (PLA) inner shell, and a hydrophilic poly(ethylene glycol) (PEG) outer shell. Octreotide (OCT), a peptide that shows strong binding affinity to somatostatin receptors, which are overexpressed on NET cells, was used as the targeting ligand. Resveratrol was physically encapsulated by the micelle with a drug loading content of 12.1%. The unimolecular micelles exhibited a uniform size distribution and spherical morphology, which were determined by both transmission electron microscopy (TEM) and dynamic light scattering (DLS). Cellular uptake, cellular proliferation, and Western blot analyses demonstrated that the resveratrol-loaded OCT-targeted micelles suppressed growth more effectively than non-targeted micelles. Moreover, resveratrol-loaded NET-targeted micelles affected MTC cells similarly to free resveratrol in vitro, with equal growth suppression and reduction in NET marker production. These results suggest that the H40-based unimolecular micelle may offer a promising approach for targeted NET therapy.

Multigland disease and slower decline in intraoperative PTH characterize mild primary hyperparathyroidism.

BACKGROUND: Many patients with primary hyperparathyroidism (PHPT) present with less severe biochemical parameters. The purpose of this study was to compare the presentation, operative findings, and outcomes of these patients with "mild" PHPT to patients with "overt" disease. METHODS: A retrospective review of a prospectively collected parathyroid database was performed to identify cases of PHPT undergoing an initial neck operation. Patients were classified as mild when either the preoperative calcium or PTH was within the normal limits. Comparisons were made with the Student's t test, Chi-squared test, or Wilcoxon rank-sum test where appropriate. Kaplan-Meier estimates were plotted for disease-free survival and compared by the log-rank test. RESULTS: Of the 1,429 patients who met inclusion criteria, 1,049 were classified as overt and 388 (27.1 %) were mild. Within the mild group, 122 (31.4 %) presented with normocalcemic PHPT and 266 (68.6 %) had a normal PTH. The two groups had similar demographics and renal function. Interestingly, the mild group had more than double the rate of kidney stones (3.1 vs. 1.3 %, p = 0.02). The mild group was less likely to localize on sestamibi scan (62.4 vs. 78.7 %, p < 0.01). Intraoperatively, more mild patients exhibited multigland disease (34.3 vs. 14.1 %, p < 0.01). When examining intraoperative PTH (IoPTH) kinetics where single adenomas were excised, the IoPTH fell at a rate of 6.9 pg/min in mild patients compared with 11.5 pg/min in the overt group (p < 0.01). Accordingly, 62.2 % of patients in the overt group and 53.3 % in the mild group were cured at 5 min postexcision (p < 0.01). There was no difference in the rates of persistence or recurrence between the groups, and disease-free survival estimates were identical (p = 0.27). CONCLUSIONS: Patients with mild PHPT were more likely to have multigland disease and a slower decline in IoPTH, but these patients can be successfully treated with surgery.

Radioguided parathyroidectomy effective in pediatric patients.

BACKGROUND: Radioguided parathyroidectomy (RGP) has been shown to be effective in adult patients with hyperparathyroidism (HPT), but the utility of RGP in pediatric patients has not been systematically examined. It is not known if adult criteria for radioactive counts can accurately detect hyperfunctioning parathyroid glands in pediatric patients. The purpose of our study was to determine the utility of RGP in children with primary HPT. MATERIALS AND METHODS: A retrospective review of our prospectively maintained single-institution database for patients who underwent a RGP for primary HPT identified 1694 adult and 19 pediatric patients aged 19 y or younger. From the adult population, we selected a control group matched three to one for gland weight and gender and compared pre- and postoperative laboratory values, surgical findings, pathology, and radioguidance values between the control and the pediatric groups. RESULTS: Excised glands from pediatric patients were smaller than those in the total adult population (437 ± 60 mg versus 718 ± 31 mg, P = 0.0004). When controlled for gland weight, ex vivo counts as a percentage of background were lower in the pediatric group (51% ± 5% versus 91% ± 11%, P = 0.04). However, ex vivo radionuclide counts >20% of the background were found in 100% of pediatric patients and 95% of the adult-matched control group. CONCLUSIONS: All pediatric patients met the adult detection criteria for parathyroid tissue removal when a RGP was performed, and 100% cure was achieved. We conclude that RGP is a useful treatment option for pediatric patients with primary HPT.

Leflunomide suppresses growth in human medullary thyroid cancer cells.

BACKGROUND: Medullary thyroid cancer (MTC) is a neuroendocrine tumor that arises from the calcitonin-secreting parafollicular cells of the thyroid gland. Leflunomide (LFN) is a disease-modifying antirheumatic drug approved for the treatment of rheumatoid arthritis, and its active metabolite teriflunomide has been identified as a potential anticancer drug. In this study we investigated the ability of LFN to similarly act as an anticancer drug by examining the effects of LFN treatment on MTC cells. METHODS: Human MTC-TT cells were treated with LFN (25-150 µmol/L) and Western blotting was performed to measure levels of neuroendocrine markers. MTT assays were used to assess the effect of LFN treatment on cellular proliferation. RESULTS: LFN treatment downregulated neuroendocrine markers ASCL1 and chromogranin A. Importantly, LFN significantly inhibited the growth of MTC cells in a dose-dependent manner. CONCLUSIONS: Treatment with LFN decreased neuroendocrine tumor marker expression and reduced the cell proliferation in MTC cells. As the safety of LFN in human beings is well established, a clinical trial using this drug to treat patients with advanced MTC may be warranted.

Early-phase technetium-99m sestamibi scintigraphy can improve preoperative localization in primary hyperparathyroidism.

BACKGROUND: In hyperparathyroidism, dual-phase technetium-99m sestamibi scintigraphy is important for parathyroid adenoma localization. We hypothesized that reviewing early-phase scans can increase localization in patients with primary hyperparathyroidism (PHPT). METHODS: We reviewed our prospectively maintained database for patients with sestamibi scans before parathyroidectomy for PHPT from 2001 to 2011. Early-phase scans were read and compared with the location of the gland(s) removed at operation. RESULTS: Of 902 patients identified, radiologists read 693 scans as positive. Of 209 negative scans, 141 (67%) were positive in the early phase; 135 (96%) correctly identified the side of the adenoma. Using radiologist reads, 35% of patients with negative scans and 41% of patients with falsely localized glands required bilateral exploration compared with 5% of patients with correctly localized glands. CONCLUSIONS: A review of early scans in patients with negative imaging increases accurate adenoma localization and allows for minimally invasive operations in more patients.

Evolution of pediatric thyroid surgery at a tertiary medical center.

BACKGROUND: Thyroidectomy in the pediatric population is often avoided due to perceived risks in children. With growing subspecialization and establishment of high volume endocrine surgery centers, the indications for thyroid surgery and extent of resection continue to change. We examined the evolution of pediatric thyroid surgery at a high volume tertiary medical center. METHODS: From our prospectively collected database, we reviewed medical records of individuals younger than 19 y who underwent thyroidectomy at our institution from 1994 to 2009. Patients were divided into two groups: (1) before establishment of our endocrine surgery center (1994-2001) and (2) since establishment of the center (2002-2009). RESULTS: We identified 78 operations performed on 74 patients with a median age of 15 (range 3-18) y. We found that the number of patients doubled in the later time period, with 26 operations in group 1 and 52 in group 2. The age of patients and percentage of females were similar between groups. After establishment of the endocrine surgery center, there was a significant increase in total thyroidectomies for all indications, including significantly more for benign disease. Overall, 9% of the patient population experienced transient complications, with no permanent complications or long-term sequelae. CONCLUSIONS: Pediatric thyroid surgery is extremely safe, especially when performed at a high volume endocrine surgery center. We more often select surgical treatment for benign disease and choose total thyroidectomy over limited resection. This may reflect increasing confidence in the safety and efficacy of surgery and reliability of thyroid hormone replacement.