The Role of Demographic and Clinical Factors in Germline Mutation Testing for Patients with Primary Hyperparathyroidism.

INTRODUCTION: Guidelines recommending genetic counseling in primary hyperparathyroidism (PHPT) vary. To further delineate current recommendations, this study examined genetic counseling referral patterns and rates of mutations in surgical patients with PHPT. PATIENTS AND METHODS: A single-institution review was performed of adult patients who underwent parathyroidectomy for presumed sporadic PHPT. Genetic testing indications of hypercalcemia onset ≤ 40 years, multigland disease (MGD), family history (FHx) of PHPT, or other clinical indications suspicious for a PHPT-related endocrinopathy were examined by demographics and mutation detection rates. RESULTS: Genetic counseling was performed in 237 (37.9%) of 625 patients. Counseling was discussed but not performed in 121 (19.4%) patients. No evidence was noted of genetic referral discussion in the remaining 267 (42.7%). Of these groups, patients who received genetic counseling were youngest, p < 0.001 [median age 55.3 (IQR 43.2, 66.7) years]. The majority of patients with indications of age ≤ 40 years (65.7%), FHx (78.0%), and other clinical indications (70.7%) underwent genetic counseling, while most with MGD (57.0%) did not. Eight mutations were detected in 227 patients (3.5%). Mutations included: MEN1 (n = 2), CDC-73 (n = 4), and CASR (n = 2). Detection was most common in patients with FHx (4/71, 5.6%), then age ≤ 40 years (3/66, 4.5%), and other clinical indications (3/80, 3.8%). No mutations were identified in 48 patients tested solely for MGD. CONCLUSIONS: Most patients with onset of hypercalcemia age ≤ 40 years, positive FHx, or other clinical concerns underwent genetic counseling, while most with MGD did not. As no germline mutations were identified in patients with MGD alone, further investigation of MGD as a sole indication for genetic counseling may be warranted.

Older Patients With Asymptomatic Primary Hyperparathyroidism: Should Criteria for Surgery Be Expanded?

Context: Patients with primary hyperparathyroidism (PHPT) can present with variable signs, symptoms, and end-organ effects. Clinical practice guidelines influence referral for consideration of parathyroidectomy. Objective: This study compared the demographic, biochemical, and symptom profile and examine indications for surgery in patients older than 50 years who underwent parathyroidectomy to determine how changes to current guidelines may affect recommendations for parathyroidectomy. Methods: A retrospective review was conducted of patients age 50 years or older who underwent initial parathyroidectomy for sporadic PHPT from 2012 to 2020. Patients were classified by indications for surgery per guideline criteria (classic, asymptomatic, and no criteria met) and age group (AG): 50 to 59 years; 60 to 69 years; 70 years or older. Patients were treated at a high-volume tertiary medical center by endocrine surgeons. Results: Of 1182 patients, 367 (31%) classic and 660 (56%) asymptomatic patients met the criteria for surgery. The most common indications for surgery were extent of hypercalcemia (51%), osteoporosis (28%), and nephrolithiasis (27%). Of the 155 (13%) patients who did not meet the criteria, neurocognitive symptoms (AG1: 88% vs AG2: 81% vs AG3: 70%; P = .14) and osteopenia (AG1: 53% vs AG2: 68% vs AG3: 68%; P = .43) were frequently observed regardless of patient age. If the age threshold of younger than 50 years was expanded to 60, 65, or 70 years, an additional 61 (5%), 99 (8%), and 124 (10%) patients in the entire cohort would have met the guideline criteria for surgery, respectively. Conclusion: Expanding current guidelines for PHPT to include a broader age range, osteopenia, and neurocognitive symptoms may allow for earlier surgical referral and evaluation for definitive treatment.

Variation in parathyroid adenoma size in patients with sporadic, primary hyperparathyroidism: small gland size does not preclude single gland disease.

PURPOSE: Small, abnormal parathyroid glands are usually associated with multigland hyperplasia in patients with primary hyperparathyroidism (pHPT). The purpose of this study was to determine the association between parathyroid adenoma size and biochemical cure rates in patients undergoing single gland parathyroidectomy. METHODS: The study included patients with sporadic pHPT who underwent initial parathyroidectomy and met intraoperative PTH criteria for cure after resection of a single adenoma (SGD). Patients were divided into quartiles (Q1 = smallest) based on gland weight and maximum dimension; cure rates were compared across groups. RESULTS: A single parathyroid adenoma was removed in 517 patients, with a median gland weight of 500 mg (range 50-11890). Median maximum gland dimension was 15 mm (range 5-55). With median follow-up of 28 months (range 6-81), the biochemical cure rate was 97.1%. There was no difference in cure rate by gland weight (Q1 94.6%, Q2 96.9%, Q3 98.4%, Q4 98.5%, p = 0.217) or maximum gland dimension (Q1 95.6%, Q2 97.6%, Q3 97.1%, Q4 98.2%, p = 0.641). When Q1 patients (by gland weight) were divided by quartile, there was no difference in cure rates (93.1% [50-140 mg]; 95.2% [150-190 mg]; 97.1% [200-230 mg]; 93.3% [240-280 mg]; p = 0.665). CONCLUSION: For patients with pHPT who underwent single gland parathyroidectomy, there was no difference in cure rates by gland weight or maximum dimension. These data suggest that the removal of parathyroid adenomas as small as 50 mg with an appropriate decline in ioPTH likely represent single gland disease and additional exploration may not be necessary.

The Clinical Utility of Preoperative Thyroglobulin for Surgical Decision Making in Thyroid Disease.

BACKGROUND: Serum thyroglobulin (Tg) levels are used to monitor for differentiated thyroid cancer (DTC) recurrence and have been correlated with posttreatment disease burden. The clinical significance of Tg in the preoperative setting to predict the risk of DTC is unclear. Our aim is to examine the clinical utility of preoperative Tg levels in those undergoing thyroidectomies for DTC or benign disease. MATERIALS AND METHODS: From a prospectively collected database, we identified 385 patients who underwent thyroidectomy from 01/14 to 12/19 and had preoperative Tg levels available. Preoperative Tg levels were compared by preoperative indication for surgery, Bethesda category of biopsied nodules, presence of DTC on surgical pathology, and number of metastatic lymph nodes. RESULTS: There was no difference in mean preoperative Tg level when comparing indication for surgery (P = 0.2) or Bethesda classification (P = 0.4). Mean preoperative Tg levels were lower in patients with DTC (238 ± 77) compared to without DTC (532 ± 97) on final pathology (P = 0.02). Among 188 DTC patients who had lymph nodes removed, there was no significant correlation between the preoperative Tg level and number of positive lymph nodes on final pathology (P = 0.4). CONCLUSIONS: Preoperative serum Tg levels were lower in patients with DTC compared to those with benign disease on final pathology and did not correlate with extent of lymph node metastasis in patients with DTC. We found that serum Tg levels obtained in the preoperative setting do not predict DTC or lymph node metastasis and, therefore, do not inform the extent of surgery for differentiated thyroid cancer.

An Institutional experience with primary hyperparathyroidism in the elderly over two decades.

BACKGROUND: Parathyroidectomy is the only curative treatment for primary hyperparathyroidism (pHPT) and is associated with low morbidity. This study examined the severity of disease and outcomes of parathyroidectomy based on patient age at a high-volume institution. METHODS: This is a retrospective review of sporadic pHPT patients who underwent initial parathyroidectomy. To study disease severity over time, patients were divided into timeframes: 1999-2007, 2007-2012, and 2013-2018. Elderly was defined as age ≥75 years. RESULTS: Over time, the elderly had progressively lower preoperative calcium (11.0, 10.7, 10.7; p = 0.05) and PTH (150.4, 111.9, 107.9; p < 0.001) levels. By age, there was no difference in preoperative calcium (10.8, 10.9; p = 0.91) or in rates of recurrent laryngeal nerve injury, hypoparathyroidism, or persistent/recurrent pHPT. CONCLUSIONS: Over the 3 time periods of the study, elderly patients had progressively lower calcium and PTH levels. There was no difference in endocrine-specific complications between the age groups, suggesting that parathyroidectomy in the elderly is safe and therefore, age-associated morbidity should not preclude parathyroidectomy.

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.

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.

Parathyroidectomy for primary hyperparathyroidism improves sleep quality: A prospective study.

BACKGROUND: This prospective survey study assessed changes in sleep quality in patients with primary hyperparathyroidism after parathyroidectomy. METHODS: Patients undergoing parathyroidectomy for primary hyperparathyroidism (n = 110) or thyroidectomy for benign euthyroid disease (control group; n = 45) were recruited between June 2013 and June 2015 and completed the Pittsburgh Sleep Quality Index preoperatively and at 1- and 6 months postoperatively. "Poor" sleep quality was defined as a score >5; a clinically important and relevant improvement was a ≥3-point decrease. RESULTS: Preoperatively, parathyroid patients had worse sleep quality than thyroid patients (mean 8.1 vs 5.3; P < .001); 76 (69%) parathyroid and 23 (51%) thyroid patients reported poor sleep quality (P = .03). Postoperatively, only parathyroid patients demonstrated improvement in sleep quality; mean scores did not differ between the parathyroid and thyroid groups at 1 month (6.3 vs 5.3; P = .12) or 6 months (5.8 vs 4.6; P = .11). The proportion of patients with a clinically important improvement in sleep quality was greater in the parathyroid group at 1 month (37% vs 10%; P < .001) and 6 months (40% vs 17%; P = .01). Importantly, there was no difference in the proportion of patients with poor sleep quality between the 2 groups at 1 month (50% vs 40%; P = .32) and 6 months (40% vs 29%; P = .22). CONCLUSION: More than two-thirds of patients with primary hyperparathyroidism report poor sleep quality. After parathyroidectomy, over one-third experienced improvement, typically within the first month postoperatively.

Delayed Calcium Normalization After Presumed Curative Parathyroidectomy is Not Associated with the Development of Persistent or Recurrent Primary Hyperparathyroidism.

BACKGROUND: Following parathyroidectomy for primary hyperparathyroidism (pHPT), serum calcium levels typically normalize relatively quickly. The purpose of this study was to identify potential factors associated with delayed normalization of calcium levels despite meeting intraoperative parathyroid hormone (IOPTH) criteria and to determine whether this phenomenon is associated with higher rates of persistent pHPT. METHODS: This was a retrospective review of 554 patients who underwent parathyroidectomy for sporadic pHPT from January 2009 to July 2013. Patients who underwent presumed curative parathyroidectomy and had elevated POD0 calcium levels (>10.2 mg/dL) were matched 1:2 for age and gender to control patients with normal POD0 calcium levels. RESULTS: Of the 554 patients, 52 (9 %) had an elevated POD0 Ca (median 10.7, range 10.3-12.2). Compared with the control group, these patients had higher preoperative calcium (12 vs. 11.1, p < 0.001) and PTH (144 vs. 110 pg/mL, p = 0.004) levels and lower 25OH vitamin D levels (26 vs. 31 pg/mL; p = 0.024). Calcium normalization occurred in 64, 90, and 96 % of patients by postoperative days (POD) 1, 14, and 30, respectively. There was no difference in rates of single-gland disease or cure rates between the groups. CONCLUSIONS: After presumed curative parathyroidectomy, nearly 10 % of patients had transiently persistent hypercalcemia. Most of these patients had normal serum calcium levels within the first 2 weeks and did not have increased rates of persistent pHPT. Immediate postoperative calcium levels do not predict the presence of persistent pHPT, and these patients may not require more stringent follow-up.

Factors that influence parathyroid hormone half-life: determining if new intraoperative criteria are needed.

IMPORTANCE: Minimally invasive parathyroidectomy using intraoperative parathyroid hormone monitoring remains the standard approach to the majority of patients with primary hyperparathyroidism. This study demonstrates that individual patient characteristics do not affect existing criteria for intraoperative parathyroid hormone monitoring. OBJECTIVE: To identify patient characteristics, such as age, sex, race, body mass index (BMI), and renal function, that may affect existing criteria for intraoperative parathyroid hormone (IOPTH) levels during minimally invasive parathyroidectomy. DESIGN: Retrospective review of a prospectively collected parathyroid database populated from August 2005 to April 2011. SETTING: Academic medical center. PARTICIPANTS: Three hundred six patients with sporadic primary hyperparathyroidism who underwent initial parathyroidectomy between August 2005 and April 2011. INTERVENTIONS: All patients underwent minimally invasive parathyroidectomy with complete IOPTH information. MAIN OUTCOME AND MEASURES: Individual IOPTH kinetic profiles were fitted with an exponential decay curve and individual IOPTH half-lives were determined. Univariate and multivariate analyses were performed to determine the association between patient demographics or laboratory data and IOPTH half-life. RESULTS: Mean age of the cohort was 60 years, 78.4% were female, 90.2% were white, and median BMI was 28.3. Overall, median IOPTH half-life was 3 minutes, 9 seconds. On univariate analysis, there was no association between IOPTH half-life and patient age, renal function, or preoperative serum calcium or parathyroid hormone levels. Age, BMI, and an age × BMI interaction were included in the final multivariate median regression analysis; race, sex, and glomerular filtration rate were not predictors of IOPTH half-life. The IOPTH half-life increased with increasing BMI, an effect that diminished with increasing age and was negligible after age 55 years (P = .001). CONCLUSIONS AND RELEVANCE: Body mass index, especially in younger patients, may have a role in the IOPTH half-life of patients undergoing parathyroidectomy. However, the differences in half-life are relatively small and the clinical implications are likely not significant. Current IOPTH criteria can continue to be applied to all patients undergoing parathyroidectomy for sporadic primary hyperparathyroidism.

Annexin-V promotes anti-tumor immunity and inhibits neuroblastoma growth in vivo.

The goal of the current study is to determine the effects of blocking phosphatidylserine (PS) on the growth of neuroblastoma in mice. PS, an anionic phospholipid restricted to the cytoplasmic surface of plasma membranes in most cells, is externalized to the surface of apoptotic cells. PS has been shown to induce immune tolerance to self-antigens. PS can also be found on the surface of live cells and in particular tumor cells. Annexin-V (AnV) is a protein that specifically binds and blocks PS. To determine the effects of blocking PS with AnV on tumor growth and immunogenicity, mice were inoculated with AGN2a, a poorly immunogenic murine neuroblastoma that expresses high level of PS on the cell surface. Survival and anti-tumor T cell response were determined. AGN2a were engineered to secrete AnV. Secreted protein effectively blocked tumor PS. 40 % of mice inoculated with AnV-expressing AGN2a cells survived free of tumor, whereas none of the mice inoculated with control cells survived (p = 0.0062). The benefits of AnV were lost when mice were depleted of T cells. The findings suggest that AnV could protect mice from tumor challenge through an immune mediated mechanism. Mice were then immunized with irradiated AnV-secreting or control cells, and challenged with wild-type AGN2a cells. AnV-secreting cell vaccine protected 80 % of mice from AGN2a challenge, while control cell vaccine prevented tumor growth in only 30 % of animals (p = 0.012). ELISPOT analysis demonstrated that AnV-secreting cell vaccine induced a greater frequency of interferon-gamma producing splenic T cells. T cells isolated from mice immunized with AnV-secreting but not control vaccine lysed AGN2a. In summary, AnV blocked PS, enhanced T cell mediated tumor immunity, and inhibited tumor growth.

Zollinger-Ellison syndrome associated with a history of alcohol abuse: coincidence or consequence?

BACKGROUND: This 47-year observational study suggests that sporadic Zollinger-Ellison (Z-E) syndrome, particularly duodenal wall gastrinomas (DWG), is associated with a history of alcohol abuse. METHODS: Thirty-nine consecutive Z-E patients were followed from 1962 through 2010. The drinking patterns of these patients were assessed and compared with 3,786 community controls. RESULTS: Thirty-five patients had extrapancreatic gastrinomas (34 DWG and/or paraduodenal lymph nodes, 1 antral gastrinoma). Total gastrectomy was done in 24; 9 underwent less extensive operations to remove DWG, and 2 patients had no operations. There were no deaths from tumor progression. Four patients presented with pancreatic gastrinoma (PG) and liver metastasis, all died from tumor progression. Alcohol abuse (>50 g/d) was documented in 81% of patients with DWG and/or paraduodenal lymph nodes. The drinking patterns (drinks per day) of DWG patients were significantly different: DWG vs community control-abstainers, 3% vs 24%; 1-2 drinks, 16% vs 62%; 3-5 drinks, 29% vs 12%; and ≥ 6 drinks, 52% vs 2.5% (P < .01). CONCLUSION: Alcohol abuse is strongly associated with and may be a risk factor for sporadic Z-E with extrapancreatic DWG. Liver metastases and tumor deaths were not observed in this subgroup, supporting the concept that DWG and PG are different tumor entities.

Primary hyperparathyroidism with a history of head and neck irradiation: the consequences of associated thyroid tumors.

BACKGROUND: Information on thyroid tumors is scant in patients with primary hyperparathyroidism (HPT) and history of head and neck irradiation. The study objective was to investigate thyroid pathology in primary HPT patients with irradiation history presenting for parathyroidectomy. METHODS: A prospective database of 1,020 parathyroidectomy patients was analyzed. 916 consecutive HPT patients were identified. History of radiation, neck ultrasound results, thyroid operations, and pathology was assessed. Patients with radiation history were compared to those with no radiation. RESULTS: Of the 916 HPT patients, 49 (5%) had a history of radiation and were more likely to have nodular thyroid disease (95% vs 52%), undergone a prior thyroidectomy (29% vs 4%), or had concurrent thyroidectomy (49% vs 26%). Nine of 49 (24%) had thyroid cancer. Of the 867 patients with no history of radiation, 259 underwent thyroid resection (32 prior and 227 concurrent) and 32 (12%) had thyroid cancer. CONCLUSION: Primary HPT patients with head and neck irradiation presenting for parathyroidectomy had marked increase in nodular thyroid disease: nearly 1 in 2 had concurrent thyroidectomy, and nearly 1 in 4 had thyroid carcinoma. High resolution ultrasound prior to parathyroidectomy detects associated thyroid pathology and allows the surgeon to plan the extent of thyroid resection.

Operative failures after parathyroidectomy for hyperparathyroidism: the influence of surgical volume.

OBJECTIVE: To determine whether surgical volume influences the cause of operative failures after parathyroidectomy for hyperparathyroidism. SUMMARY AND BACKGROUND DATA: The surgical success rate for hyperparathyroidism from high-volume centers exceeds 95%, but some patients have unsuccessful parathyroidectomies. Although operative failure can be due to hyperfunctioning parathyroid glands in ectopic locations, less experienced surgeons may be more likely to miss an abnormal parathyroid in normal anatomic locations, which we describe as "preventable operative failure." METHODS: We used 2 prospective databases containing over 2000 consecutive patients who underwent parathyroidectomy. We identified 159 patients with persistent/recurrent hyperparathyroidism subsequently cured with additional surgery. The initially failed operations were classified as being performed at high- (>50 cases/yr) or low-volume (<50 cases/yr) hospitals. Hospital volume was obtained from a Wisconsin state database of 89 hospitals, which reported 6336 parathyroid operations during the same decade. RESULTS: Patients who initially failed their operation performed at the high- or low-volume centers were similar with regard to age, laboratory values, gender, and parathyroid weights. Despite a higher incidence of multigland disease (which increases the likelihood of operative failure) in the high-volume group, patients in the low-volume group were more likely to have a missed parathyroid gland in a normal anatomic location (89% vs. 13%, P < 0.0001), and thus a higher proportion of preventable operative failures. CONCLUSIONS: Surgical volume influences the failure pattern after parathyroidectomy for hyperparathyroidism. Preventable operative failures are more common in low-volume centers.

Reoperative parathyroidectomy: an algorithm for imaging and monitoring of intraoperative parathyroid hormone levels that results in a successful focused approach.

BACKGROUND: Advances in preoperative imaging and use of intraoperative parathyroid hormone (IOPTH) levels are changing the approach to reoperative parathyroidectomy (ReopPTX). We sought to develop a protocol for imaging and IOPTH monitoring that allows for a focused, successful operative approach. METHODS: We reviewed our prospective database of consecutive patients with primary hyperparathyroidism who underwent ReopPTX with IOPTH monitoring between December 1999 and June 2007. RESULTS: Thirty-nine patients underwent 43 ReopPTXs for persistent (79%)/recurrent (21%) disease. All underwent ultrasonography and sestamibi imaging; 24 cases (56%) underwent additional imaging studies. Sensitivity of ultrasonography was 56%, sestamibi 53%, both studies 67%, computed tomography (CT) 48%, magnetic resonance imaging (MRI) 67%, and selective venous sampling (SVS) 50%. IOPTH monitoring predicted accurately cure in 100% and failure in 78%. A focused/unilateral approach was performed in 60%; median operative time was 45 minutes (range, 12-127). At last follow-up, 36 (92%) patients were normocalcemic. CONCLUSIONS: We propose that ultrasonography and sestamibi studies should be done before all ReopPTXs; failure to localize should prompt sequential CT, MRI, and SVS until localization is achieved. IOPTH monitoring defines cure and is recommended for all ReopPTXs. This algorithm allows for a focused operative approach in >50% of ReopPTXs with operative times comparable with first-time, minimally invasive parathyroidectomy.

Induction of cytolytic T lymphocytes against pediatric solid tumors in vitro using autologous dendritic cells pulsed with necrotic primary tumor.

PURPOSE: Effective and generally applicable methods for generating cancer vaccines in children have not been defined. Dendritic cells (DCs) are the most potent professional antigen-presenting cells capable of activating primary cytolytic T cells. We tested the ability of DCs generated from pediatric patients' peripheral blood monocytes and pulsed with a necrotic tumor to activate autologous tumor-specific cytolytic T cells. METHODS: Tumor and peripheral blood cells were obtained from pediatric patients undergoing biopsy or resection for advanced solid tumors according to an institutional research board-approved protocol and after acquiring informed consent from them. To generate DCs, we treated peripheral blood monocytes with granulocyte-macrophage colony stimulating factor and interleukin (IL)-4. Maturation was induced with a cytokine cocktail (CC) containing tumor necrosis factor-alpha, IL-6, IL-1beta, and prostaglandin E2. The DC phenotype was assayed using flow cytometry. Tumor necrosis was induced by exposure to UV-B irradiation (1000 mJ). Dendritic cells pulsed with a UV-B-treated primary tumor and matured with CC were used to stimulate autologous peripheral blood lymphocytes weekly. Tumor-specific cytolytic activity was assayed using 4-hour 51Cr release. RESULTS: Peripheral blood monocytes isolated from pediatric patients differentiated into immature DCs (CD14-, MHCII+ [major histocompatibility complex], CD80(low), CD86(low)) in the presence of granulocyte-macrophage colony stimulating factor and IL-4. Cytokine cocktail induced maturation of DCs, as characterized by increased expressions of MHCII, CD83, CD80, and CD86. Patients' peripheral blood lymphocytes stimulated in vitro with DCs loaded with a necrotic primary tumor and matured with CC specifically lysed autologous neuroblastoma in 7 of 9 patients. CONCLUSION: Dendritic cells generated from the peripheral blood of children with advanced solid tumors and pulsed with a necrotic primary tumor undergo maturation and effectively stimulate autologous tumor-specific cytolytic T cells in vitro. We describe a simple method for generating a vaccine capable of activating cytotoxic T cells against pediatric solid tumors that does not require the genetic identification of tumor-associated antigens.

Neuroblastoma cells inhibit the immunostimulatory function of dendritic cells.

PURPOSE: Dendritic cells (DC) are critical for induction of antitumor immunity. Recent studies suggest that tumors may avoid immune destruction by inhibiting DC function. The authors investigated the effect of neuroblastoma (NB) on surface antigen expression and T cell activation by DCs. METHODS: DCs were generated in the presence of granulocyte and macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) from peripheral blood of healthy donors. On day 6 of culture, DCs were exposed to human NB cells and were analyzed by flow cytometry. RESULTS: The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) failed to upregulate the expression of HLA-DR and costimulatory molecule CD86 by DCs that were cultured with NB. Conversely, upregulation was preserved when DCs were cultured in the absence of NB. Exposure to NB also led to apoptosis of DCs as shown by 2-fold increase in surface phosphatidylserine. It appears that direct contact was required to inhibit DC maturation, because DCs separated from NB cells using a transwell insert did not suppress surface antigen expression. Finally, DCs exposed to NB inhibited the proliferation of allogeneic T cells in mixed lymphocyte reactions. CONCLUSIONS: These findings have significant implications for tumor-pulsed DC vaccines in the treatment of NB and suggest a mechanism by which NB escape rejection.