A 14-year-old girl with premature ovarian insufficiency but with a positive pregnancy test.

OBJECTIVES: Childhood cancer survivors are at risk for premature ovarian insufficiency, especially after treatment with alkylating agents. The objective of this report is to highlight a case in which this phenomenon caused a false-positive pregnancy test. CASE PRESENTATION: A workup was performed in a 14-year-old girl with a positive pregnancy test. She was diagnosed with stage IV neuroblastoma of the left adrenal gland at the age of 4 years. She received extensive treatment, including alkylating agents, and had been diagnosed with premature ovarian insufficiency. An LH/hCG suppression test was performed using high dose 17 bèta-estradiol: hCG levels normalized. CONCLUSIONS: The pregnancy test was false-positive due to production of low amounts of hCG by the pituitary gland as a result of high LH concentrations following premature ovarian insufficiency. It may be helpful to perform the LH/hCG suppression test to prove pituitary origin of the hCG overproduction.

Changes in thyroid function parameters 3 months after allogeneic and autologous hematopoietic stem cell transplantation in children.

BACKGROUND: Thyroid dysfunction (hypo- and hyperthyroidism) has been reported as a late effect after hematopoietic stem cell transplantation (HSCT) in children. Short-term effects of HSCT on thyroid function parameters are, however, unclear. METHODS: We prospectively evaluated thyroid function parameters before and 3 months after HSCT in all children (<21 years) who underwent HSCT during a 2-year period in the Princess Máxima Center, the Netherlands. RESULTS: Among 72 children, none had thyroidal hypothyroidism or hyperthyroidism 3 months after HSCT. Changes in thyroid function parameters (either aberrant thyroid-stimulating hormone [TSH] or free thyroxine [FT4] concentrations) were found in 16% before and in 10% 3 months after HSCT. Reverse triiodothyronine (rT3) was found elevated in 9.3% before and in 37% 3 months after HSCT, which could be related to poor physical condition. An individual decline in FT4 concentration of ≥20% was found in 10.5% (6/57) 3 months after HSCT. CONCLUSION: In conclusion, thyroidal hypo- and hyperthyroidism are very rare 3 months after HSCT. These results indicate that surveillance for hypo- and hyperthyroidism may start later in time. The changes in thyroid function parameters found 3 months after HSCT might reflect euthyroid sick syndrome.

Thyroid Profile in the First Three Months after Starting Treatment in Children with Newly Diagnosed Cancer.

BACKGROUND: Thyroid hormone anomalies during childhood might affect neurological development, school performance and quality of life, as well as daily energy, growth, body mass index and bone development. Thyroid dysfunction (hypo- or hyperthyroidism) may occur during childhood cancer treatment, although its prevalence is unknown. The thyroid profile may also change as a form of adaptation during illness, which is called euthyroid sick syndrome (ESS). In children with central hypothyroidism, a decline in FT4 of >20% has been shown to be clinically relevant. We aimed to quantify the percentage, severity and risk factors of a changing thyroid profile in the first three months of childhood cancer treatment. METHODS: In 284 children with newly diagnosed cancer, a prospective evaluation of the thyroid profile was performed at diagnosis and three months after starting treatment. RESULTS: Subclinical hypothyroidism was found in 8.2% and 2.9% of children and subclinical hyperthyroidism in 3.6% and in 0.7% of children at diagnosis and after three months, respectively. ESS was present in 1.5% of children after three months. In 28% of children, FT4 concentration decreased by ≥20%. CONCLUSIONS: Children with cancer are at low risk of developing hypo- or hyperthyroidism in the first three months after starting treatment but may develop a significant decline in FT4 concentrations. Future studies are needed to investigate the clinical consequences thereof.

Testosterone analysis in castrated prostate cancer patients: suitability of the castration cut-off and analytical accuracy of the present-day clinical immunoassays.

OBJECTIVES: Testosterone testing is relevant for evaluating castration adequacy and diagnosis of castration-resistant prostate cancer (PCa). However, the recommended testosterone cut-off of 1.7 nmol/L (50 ng/dL) to define adequate castration is based on consensus and not validated for the automated immunoassays (AIA) used in today's medical laboratories. Furthermore, appropriate population intervals have not been determined by a state-of-the-art assay. We investigated the analytical suitability of this cut-off and the accuracy of the present-day AIAs for testosterone analysis in castrated PCa patients. METHODS: Leftover serum from 120 PCa patients castrated with luteinizing hormone-releasing hormone agonists was analysed for testosterone by five methods: Architect i2000 (Abbott), Access (Beckman), Cobas 6000 (Roche), Atellica (Siemens), LC-MS/MS. For all assays, the castration 95th, 97.5th and 99th percentile upper limits were determined. Furthermore, Passing-Bablok regression, mean bias and Spearman's correlation coefficients were compared to the LC-MS/MS method and total error based on biological variation. RESULTS: All castration upper limits, ranging from 0.472 nmol/L (LC-MS/MS) to 1.25 nmol/L (Access) (95% percentile), were significantly lower than the current castration cut-off (1.7 nmol/L). Slopes of Passing-Bablok regressions comparing the AIA with the LC-MS/MS method ranged from 1.4 (Cobas and Atellica) to 3.8 (Access). The Architect showed the highest correlation with LC-MS/MS (ρ=0.58). All AIA failed to meet the desirable total error criterion. CONCLUSIONS: These results suggest that a lower general testosterone castration cut-off may be more appropriate in evaluating the adequacy of castration in PCa and that present-day AIA lack analytical accuracy to quantify testosterone levels in castrated PCa.

Impact of Thyroglobulin and Thyroglobulin Antibody Assay Performance on the Differential Classification of DTC Patients.

CONTEXT: Measurements of thyroglobulin (Tg) and Tg antibodies are crucial in the follow-up of treated differentiated thyroid cancer (DTC) patients. Interassay differences may significantly impact follow-up. OBJECTIVE: The aim of this multicenter study was to explore the impact of Tg and Tg antibody assay performance on the differential classification of DTC patients, as described in national and international guidelines. DESIGN: Four commonly used Tg and Tg antibody assays were technically compared to reflect possible effects on patients with DTC follow-up. Storage stability at different storage temperatures was also investigated for LIAISON® and Kryptor assays, as this is an underexposed topic in current literature. RESULTS: B.R.A.H.M.S. assays yield approximately 50% lower Tg values over the whole range compared to the DiaSorin and Roche assays investigated. These differences between assays may result in potential misclassification in up to 7% of patients if fixed cutoffs (eg, 1 ng/mL) are applied. Poor correlation was also observed between the Tg antibody assays when the method-specific upper limits of normal are used as cutoffs. Storage of Tg and Tg antibodies was possible for 3 to 4 weeks at -20°C and -80°C. Calibration of the assays, however, was found to be crucial for stable results over time. CONCLUSIONS: Technical aspects of Tg and Tg antibody assays, including interassay differences, calibration and standardization, and cutoff values, may have a significant clinical impact on the follow-up of DTC patients.

Clinical Applicability of Low Levels of Thyroglobulin Autoantibodies as Cutoff Point for Thyroglobulin Autoantibody Positivity.

BACKGROUND: Thyroglobulin (Tg) is an established tumor marker in differentiated thyroid carcinoma (DTC). However, Tg assays can be subject to interference by autoantibodies against Tg (TgAbs). No clinical consensus exists on the cutoff value of TgAb positivity and its relationship to Tg assay interference. The aims of this study were to investigate the most applicable cutoff value for TgAb positivity in clinical practice and to evaluate whether tumor characteristics differ between TgAb+ and TgAb- patients during ablation therapy using the manufacturer's cutoff (MCO) and institutional cutoff (ICO). METHODS: This single-center cohort study included 230 DTC patients diagnosed between January 2006 and December 2014. Serum Tg and TgAbs were measured with the Tg-IRMA (Thermo Fisher Scientific) and ARCHITECT Anti-Tg (Abbott Laboratories) assays. Patients were divided into TgAb- and TgAb+ based on the limit of detection (LoD; ≥0.07 IU/mL), functional sensitivity (FS; ≥0.31 IU/mL), MCO (≥4.11 IU/mL), and ICO (≥10 IU/mL). RESULTS: All patients were TgAb+ based on the LoD; one patient was negative on FS. Fifty-five (23.9%) and 34 (14.8%) patients had TgAbs above the MCO and ICO, respectively. Histology, presence of multifocality, tumor-node-metastasis, and American Thyroid Assocation risk stratification did not differ between TgAb- and TgAb+ patients using MCO and ICO during ablation. CONCLUSIONS: This study supports the use of a higher cutoff value than that of the FS for TgAb positivity in clinical settings. The LoD and FS are too sensitive to discriminate TgAb positivity and negativity in DTC patients during ablation therapy. The presence of TgAbs during ablation is not related to tumor characteristics and risk profile. This implies that TgAb positivity should not be considered a separate risk factor.

Prediagnostic Serum Vitamin D Levels and the Risk of Crohn's Disease and Ulcerative Colitis in European Populations: A Nested Case-Control Study.

Background: A low vitamin D status has been put forward as a potential risk factor for the development of inflammatory bowel disease (IBD). This study investigated the association between prediagnostic circulating vitamin D concentrations and dietary intakes of vitamin D, and the risk of Crohn's disease (CD) and ulcerative colitis (UC). Methods: Among 359,728 participants of the European Prospective Investigation into Cancer and Nutrition cohort, individuals who developed CD or UC after enrollment were identified. Each case was matched with2 controls by center, gender, age, date of recruitment, and follow-up time. At cohort entry, blood samples were collected and dietary vitamin D intakes were obtained from validated food frequency questionnaires. Serum 25-hydroxyvitamin D levels were measured using liquid chromatography-tandem mass spectrometry. Conditional logistic regression was performed to determine the odds of CD and UC. Results: Seventy-two participants developed CD and 169 participants developed UC after a median follow-up of 4.7 and 4.1 years, respectively. Compared with the lowest quartile, no associations with the 3 higher quartiles of vitamin D concentrations were observed for CD (p trend = 0.34) or UC (p trend = 0.66). Similarly, no associations were detected when serum vitamin D levels were analyzed as a continuous variable. Dietary vitamin D intakes were not associated with CD (p trend = 0.39) or UC (p trend = 0.83). Conclusions: Vitamin D status was not associated with the development of CD or UC. This does not suggest a major role for vitamin D deficiency in the etiology of IBD, although larger studies are needed to confirm these findings.

Role of Vitamin D in Maintaining Renal Epithelial Barrier Function in Uremic Conditions.

As current kidney replacement therapies are not efficient enough for end-stage renal disease (ESRD) treatment, a bioartificial kidney (BAK) device, based on conditionally immortalized human proximal tubule epithelial cells (ciPTEC), could represent an attractive solution. The active transport activity of such a system was recently demonstrated. In addition, endocrine functions of the cells, such as vitamin D activation, are relevant. The organic anion transporter 1 (OAT-1) overexpressing ciPTEC line presented 1α-hydroxylase (CYP27B1), 24-hydroxylase (CYP24A1) and vitamin D receptor (VDR), responsible for vitamin D activation, degradation and function, respectively. The ability to produce and secrete 1α,25-dihydroxy-vitamin D3, was shown after incubation with the precursor, 25-hydroxy-vitamin D3. The beneficial effect of vitamin D on cell function and behavior in uremic conditions was studied in the presence of an anionic uremic toxins mixture. Vitamin D could restore cell viability, and inflammatory and oxidative status, as shown by cell metabolic activity, interleukin-6 (IL-6) levels and reactive oxygen species (ROS) production, respectively. Finally, vitamin D restored transepithelial barrier function, as evidenced by decreased inulin-FITC leakage in biofunctionalized hollow fiber membranes (HFM) carrying ciPTEC-OAT1. In conclusion, the protective effects of vitamin D in uremic conditions and proven ciPTEC-OAT1 endocrine function encourage the use of these cells for BAK application.

Additional value of a high sensitive thyroglobulin assay in the follow-up of patients with differentiated thyroid carcinoma.

OBJECTIVE: Thyroglobulin (Tg) is an excellent tumour marker, as detectable or increasing Tg levels are highly indicative of persistent or recurrent differentiated thyroid carcinoma (DTC). The clinical value of a highly sensitive (hs)-Tg assay in patients with DTC has not yet been established. The aim of this study was to investigate the additional value of unstimulated hs-Tg measurements (Tg-on) compared to stimulated IRMA-Tg measurements (Tg-off) in the follow-up of patients with DTC. DESIGN, PATIENTS, MEASUREMENTS: We retrospectively studied patients treated for DTC between 2006 and 2013 and compared hs-Tg and IRMA-Tg measurements. The study group consisted of 99 DTC patients in remission; Tg-on was measured 3 months after remnant ablation and Tg-off 6 months after ablation. RESULTS: In the study group, 44 patients showed a hs-Tg-on <0·15 µg/l (functional sensitivity); of these, 43 had an IRMA-Tg-off measurement <1·0 µg/l, resulting in a negative predictive value of 97·7% and a positive predictive value of 56·4%. CONCLUSIONS: The hs-Tg-on measurement is able to predict patients with an IRMA-Tg-off <1·0 µg/l, and therefore decreases the need for Tg stimulation after ablation.

Antimüllerian hormone: prediction of cumulative live birth in gonadotropin-releasing hormone antagonist treatment for in vitro fertilization.

OBJECTIVE: To assess the accuracy of antimüllerian hormone (AMH) in predicting cumulative live birth rate (CLBR) within 1 year after treatment initiation in GnRH antagonist treatment cycles for in vitro fertilization (IVF). DESIGN: Observational (retrospective) substudy as part of an ongoing prospective cohort study. SETTING: University medical center. PATIENT(S): A total of 487 patients scheduled for IVF/intracytoplasmic sperm injection (ICSI). INTERVENTION(S): Patients starting their first IVF/ICSI cycle with 150 or 225 IU recombinant FSH and GnRH antagonist cotreatment were included. Serum samples collected before the first IVF treatment were used to determine AMH. Treatment data after treatment initiation for a maximum of 1 year were recorded. MAIN OUTCOME MEASURE(S): Prediction of CLBR with the use of AMH. RESULT(S): The model for predicting CLBR within 1 year included age at first treatment, AMH, type of infertility, and previous assisted reproductive technology treatment leading to live birth. The accuracy in discriminating between women who did or did not achieve a live birth was only 59%. AMH had intermediate added value in the prediction of CLBR as demonstrated by the net reclassification improvement (total 29.8). A nomogram based on age and AMH was developed by which a subgroup of patients could be identified with the poorest pregnancy prospects. CONCLUSION(S): The predictive accuracy of AMH for 1-year CLBR in GnRH antagonist treatment cycles was limited and did not yield much additional value on top of age. Withholding treatment based on predictors such as age and AMH, or a combination, remains problematic. CLINICAL TRIAL REGISTRATION NUMBER: www.clinicaltrials.gov, NCT02309073.

Alphafetoprotein in the Dutch External Quality Assurance programme: a need for improvement.

BACKGROUND: Elevated alphafetoprotein (AFP) concentrations may result from a variety of clinical conditions, but their role as an important tumour marker has been well established. There may be differences in AFP values due to laboratories using different methods, even though most methods have been calibrated with the same international standard (WHO IS 72/225). Therefore it is important to know the analytical performance of the various methods in relation to the analytical requirements for AFP measurement. METHODS: Annually, from January 2005 to July 2010, the results were analysed from the 65-75 laboratories that took part in the AFP survey of the External Quality Assurance programme of the Foundation Quality Control Medical Laboratories (the SKML/Binding Analysis) in the Netherlands. RESULTS: The Elecsys/Modular (36%) and the Immulite 2000/2500 (29%) are the methods used most. The methods show, on average, up to 15% positive and 12% negative bias, compared with the all-laboratory trimmed mean. Of the laboratories using the Immulite or the Elecsys/Modular analyser, over 70% show sufficient analytical performance to meet the Fraser criterion for method imprecision. Of the laboratories using a different method, over 50% do not meet this criterion. CONCLUSIONS: AFP immunoassays suffer from method bias, even though all methods have been calibrated with the same international standard. Some of the methods used show insufficient performance.

Administration route-dependent effects of estrogens on IGF-I levels during fixed GH replacement in women with hypopituitarism.

OBJECTIVE: GH-deficient women using oral estradiol treatment require higher doses of recombinant human GH (rhGH) to achieve similar IGF-I levels when compared with men and women on transdermal estradiol replacement. The aim of this study was to evaluate the effects of oral versus transdermal estrogen administration at similar plasma estradiol levels on IGF-I, IGF-binding protein-3, and sex hormone-binding globulin (SHBG) concentrations. DESIGN: Parallel crossover study in which two groups of hypogonadal and GH-deficient women with fixed and stable rhGH replacement passed through four different estradiol treatment schemes (2 and 4 mg oral, and 50 and 100 microg transdermal estradiol) with a duration of four cycles each to ensure a new steady state. Group I (18 patients using oral estradiol prior to the study) was treated with oral followed by transdermal estradiol and group II (five patients with transdermal estradiol prior to inclusion) with transdermal followed by oral estradiol. RESULTS: Estradiol concentrations were lowest during 50 microg transdermal and highest during 4 mg oral estradiol treatment. Estradiol concentrations did not differ during 100 microg transdermal and 2 mg oral treatment. Nevertheless, IGF-I levels were significantly higher during 100 microg transdermal when compared with 2 mg oral treatment (P=0.005 in group I and 0.02 in group II), while SHBG levels were significantly lower (P=0.002 in group I and P=0.004 in group II). SHBG and IGF-I concentrations were negatively correlated (R=-0.41, P=0.0001). CONCLUSION: During fixed GH replacement, the route of estrogen administration is a determinant of IGF-I levels in hypogonadal GH-deficient women.

Multicenter evaluation of a rapid electrochemiluminescent adrenocorticotropic hormone (ACTH) immunoassay.

BACKGROUND: Measuring plasma adrenocorticotropic hormone (ACTH) is a key step in the differential diagnosis of hypothalamic-pituitary-adrenal disorders. METHODS: The recently developed electrochemiluminescence Elecsys ACTH immunoassay (Roche Diagnostics, Mannheim, Germany) was evaluated at six clinical laboratories on the Modular E170 and/or the Elecsys 2010 (Roche Diagnostics) immunoanalysers. RESULTS: The within-run and between-run imprecision was

Acromegaly in a multiple endocrine neoplasia type 1 (MEN1) family with low penetrance of the disease.

Multiple endocrine neoplasia type 1 (MEN1) is an inherited syndrome that is characterised by the occurrence of tumours in the parathyroid glands, the endocrine pancreas, the pituitary gland and the adrenal glands and by neuroendocrine carcinoid tumours, often at a young age. The penetrance of MEN1 among gene carriers is reported to be high; 82-99% at age 50. We present a patient with a history of parathyroid adenomas also showing signs of acromegaly. He turned out to be a carrier of a MEN1 germ-line mutation in intron 3 (IVS3-6C > G). This germ-line mutation was also found in nine of his family members. However, none of these relatives have developed any MEN1-related lesion yet, although several are older than 60 years. To our knowledge, a MEN1 family with as few clinical features as this family has not been reported to date. Because MEN1 patients have an increased risk of developing acromegaly, insulin-like growth factor (IGF-I) levels are monitored periodically. We investigated whether IGF-I levels might serve as a presymptomatic marker for acromegaly; 9% (3/33) of MEN1 patients showed temporary IGF-I elevations. One patient (1/3) later developed clinical signs of acromegaly. Possibly, acromegaly in MEN1 is preceded by a transient preacromegalic state.

Repeated [131I]metaiodobenzylguanidine therapy in two patients with malignant pheochromocytoma.

CONTEXT: Approximately 10% of pheochromocytomas are malignant with a 5-yr survival rate of less than 40%. Promising results have been published on single high-dosage [131I]metaiodobenzylguanidine ([131I]MIBG) treatment for malignant pheochromocytoma. We present our experience with multiple intermediate-dosage [131I]MIBG therapy instead of single high-dosage therapy. SETTING AND PATIENTS: The study took place at University Medical Centers and included two patients (one male, 36 yr of age, and one female, 43 yr of age) with widely spread metastatic pheochromocytoma and bad prognosis because of liver and lung metastases. INTERVENTIONS: Instead of a single high dosage, these two patients were treated with multiple intermediate dosages of [131I]MIBG. The first patient received 37 GBq (1 Ci) [131I]MIBG in five sessions [7400 MBq (200 mCi) each; interval range, 2-11 months]; the second patient received 66.6 GBq (1.8 Ci) [131I]MIBG in 12 sessions [5550 MBq (150 mCi) each; interval range, 2-14 months]. OUTCOME MEASURES: We measured efficacy, toxicity, and survival. RESULTS: Both patients had a complete symptomatic response and a partial tumor volume response. The first patient had a partial biochemical response, the second a complete biochemical response. In both cases, toxicity has been confined to nausea during treatment. Hematological toxicity was minimal, and both patients stayed euthyroid. The survival (so far) of these patients was 5 yr (clinical case 1) and 16 yr (clinical case 2) after initial diagnosis. CONCLUSIONS: Repeated intermediate-dosage [131I]MIBG treatment appears to be a reliable and well-tolerated radionuclide therapy and might be a useful adjunct in patients with malignant pheochromocytoma, providing longstanding palliation and prolonged survival.

The spectrum of carcinoid tumours and carcinoid syndromes.

Carcinoids are neuroendocrine tumours of the gut which may also be found in the bronchus, pancreatic islets and retroperitoneum. They probably arise from gastrointestinal or bronchopulmonary pluripotential stem cells. Carcinoid tumours derived from these cells are potentially malignant; the strength of the tendency for aggressive growth correlates with the site of origin, depth of local penetration and the size of the tumour. Carcinoids occur sporadically or result from specific hereditary tumour syndromes. Mutations and/or aberrant expression of specific genes induce and promote tumour growth. Clinical features include local symptoms due to angulation or obstruction and hepatomegaly due to liver metastases. The carcinoid syndrome commonly involves flushing, diarrhoea, bronchospasm and hypotension. Other distinct syndromes may be caused by tumour release of products that may also be used as biochemical markers in diagnosis and follow-up. Scanning using radiolabelled octreotide, an analogue of somatostatin, sensitively identifies occult primary and metastatic deposits. Localized carcinoid tumours should be resected. Some patients benefit from hepatic resection. Palliation of symptoms is best achieved with octreotide. Hepatic artery chemoembolization may produce long-acting palliation. Further genetic characterization of the different types and stages of carcinoid development as well as assessment of gene expression profiles may improve differential diagnosis, prognosis and treatment.

Steroids in adult men with type 1 diabetes: a tendency to hypogonadism.

OBJECTIVE: To compare steroids and their associations in men with type 1 diabetes and healthy control subjects. RESEARCH DESIGN AND METHODS: We studied 52 adult men with type 1 diabetes without microvascular complications, compared with 53 control subjects matched for age and BMI. Steroids and their binding globulins were assessed in a single venous blood sample and a 24-h urine sample. RESULTS: In adult men with type 1 diabetes, total testosterone did not differ from healthy control subjects, but sex hormone-binding globulin (SHBG) (42 [14-83] vs. 26 [9-117] nmol/l, P < 0.001), cortisol-binding globulin (CBG; 0.87 +/- 0.17 vs. 0.73 +/- 0.10 nmol/l, P < 0.001), and cortisol levels (0.46 +/- 0.16 vs. 0.39 +/- 0.14 nmol/l, P < 0.01) were higher. The free testosterone index was lower (60 [17-139] vs. 82 [24-200], P < 0.001), and the calculated free testosterone was slightly lower (497 [115] vs. 542 [130], P < 0.064), but the pituitary-gonadal axis was not obviously affected in type 1 diabetes. The calculated free serum cortisol was not different, and 24-h urinary free cortisol excretion was lower in type 1 diabetes (121 [42-365] vs. 161 [55-284] nmol/24 h, P < 0.009). Testosterone was mainly associated with SHBG. Estimated portal insulin was a contributor to SHBG in control subjects but not in type 1 diabetes. Cortisol was associated with CBG. HbA(1c) contributed to CBG in men with diabetes but not in control subjects, whereas estimated portal insulin did not contribute. CONCLUSIONS: Adult men with fairly controlled type 1 diabetes without complications who are treated with subcutaneous insulin have a tendency to hypogonadism, as reflected by lower free testosterone levels in the presence of similar total testosterone levels and higher SHBG levels.