Improving the prediction of persistent and recurrent differentiated thyroid cancer using the American Thyroid Association 2015 risk stratification system.

PURPOSE: The 2015 American Thyroid Association risk stratification system (ATA RSS) is used in patients with differentiated thyroid carcinoma (DTC) to assess their risk of persistent/recurrent disease. Our aims were to validate the 2015 ATA RSS in a registry of DTC patients and to examine whether the addition of factors not included in it, such as pre-radioactive iodine therapy stimulated thyroglobulin (pre-RAI sTg), gender, and age could increase its predictive ability. METHODS: We studied 403 patients with DTC, treated at a tertiary center from 1990 to 2018 and subjected to total thyroidectomy. All patients had received RAI therapy, except those with low-risk papillary microcarcinoma. RESULTS: Of our patients, 81.9% were women and 91.1% had papillary thyroid carcinoma. After a median follow-up of 5.0 years, 53 cases of persistent and 21 cases of recurrent disease were recorded. The proportion of variance explained (PVE) regarding the outcome (presence or absence of recurrent/persistent disease) using the 2015 ATA RSS alone was 18.3% (persistence) and 16.9% (recurrence), increasing to 74.4% and 52.0%, respectively, when pre-RAI sTg was added to the logistic regression model. Gender and age were not associated with the disease outcome. In ROC analysis, pre-RAI sTg had a high predictive value for persistent (AUC 0.983, 95% CI 0.962-1.000) and recurrent disease (AUC 0.856, 95% CI 0.715-0.997). The optimal cut-offs and sensitivity, specificity, and positive and negative predictive value for pre-RAI sTg were the following: for persistence 12.75 ng/ml, 100%, 90.5%, 64%, and 100%, and for recurrence 8.05 ng/ml, 77.8%, 85.5%, 36.8%, and 97%. CONCLUSIONS: The 2015 ATA RSS displayed moderate performance in predicting recurrent/persistent disease in patients with DTC, which improved with the inclusion of pre-RAI sTg values; pre-RAI sTg was an independent predictor of the disease outcome, with high negative prognostic value.

Thyroid-stimulating hormone is not the primary regulator of thyroid development in euthyroid children and adolescents living in an iodine-replete area.

OBJECTIVES: It is known that there are multiple factors which can affect thyroid gland development during childhood and adolescence. Our aim was to investigate this issue by examining the relationships between age, sex, several anthropometric parameters, pubertal status, thyroid function tests, and iodine intake status with thyroid volume (TV) in children and adolescents. STUDY DESIGN: This was a cross-sectional field study conducted in 11 representative cities and villages of Uzbekistan. Six hundred and ten children and adolescents participated. Anthropometric indices and TV were estimated. In addition, thyroid function tests (TFTs) and urinary iodine excretion (UIE) measures were obtained. RESULTS: Median UIE was 151 µg/L, thus the studied areas were iodine-sufficient. TFTs fluctuated in both genders during childhood and adolescence and the thyroid growth spurt was observed, in both sexes, at the ages of 12 and 13 years, which coincided with the age of menarche in girls. Thyroid volume was positively correlated with body surface area (BSA) (r = 0.800, p < 0.001), age (r = 0.780, p < 0.001), fat-free mass (FFM) (r = 0.797, p < 0.001) and negatively correlated with serum TSH (r = -0.154, p = 0.05). No association between thyroid volume and UIE was observed. CONCLUSIONS: In euthyroid children and adolescents living in iodine-replete areas, thyroid gland development appears to follow the pattern of linear growth and displays a growth spurt at the onset of puberty, probably due to the abrupt increase of circulating sex steroids. At this age, TSH does not appear to be the main regulator of thyroid gland development.

Improved levothyroxine pharmacokinetics after bariatric surgery.

BACKGROUND: The absorption of levothyroxine (LT4) is affected by many factors. Bariatric surgery is recommended in severely obese patients. The aim of this study was to determine the consequences of bariatric surgery on LT4 pharmacokinetic parameters, and to identify the regions of the gastrointestinal tract where LT4 is absorbed in patients with severe obesity before and after surgery. METHODS: We studied 32 severely obese nonhypothyroid patients who underwent sleeve gastrectomy (SG; n=10), Roux-en-Y gastric bypass (RYGBP; n=7), or biliopancreatic diversion with long limbs (BPD-LL; n=15). Before surgery, from 8:00 a.m., blood samples were collected before and every 30 minutes after the oral administration of a solution of 600 µg of LT4. The same procedure was repeated 35 days after surgery. We estimated the pharmacokinetic parameters of LT4 before and after surgery, including the area under the curve (AUC), the peak thyroxine concentration (Cmax), and the time to peak thyroxine concentration (Tmax). RESULTS: Following surgery, in the SG group, the mean AUC was higher than it was before surgery (18.97±6.01 vs. 25.048±6.47 [µg/dL]·h; p<0.01), whereas the values of Cmax and Tmax were similar to those before surgery. In the RYGBP group, mean AUC, Cmax, and Tmax were similar before and after surgery. In the BPD-LL group, mean AUC and Cmax were higher after surgery than before (14.18±5.64 vs. 25.51±9.1 [µg/dL]·h, p<0.001; 5.62±1.34 vs. 8.16±2.57 µg/dL, p<0.001, respectively), whereas Tmax was similar. CONCLUSIONS: The pharmacokinetic parameters of LT4 absorption are improved following SG and BPD-LL types of bariatric procedures. We conclude that the stomach, the duodenum, and the upper part of the jejunum are not sites for LT4 absorption, because in the above-mentioned bariatric procedures these are bypassed or removed.

The expression of omental 11ß-HSD1 is not increased in severely obese women with metabolic syndrome.

OBJECTIVE: Plasma cortisol in obese subjects does not differ from that in normoweight subjects. Extra-adrenal cortisol production by 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) can result in local hypercortisolemia. The aim of the present study was to examine the role of visceral hypercortisolemia in the development of metabolic syndrome in severe obesity. METHODS: Eight lean women during hysterectomy (controls) and 19 severely obese women during bariatric surgery were studied, 8 without metabolic syndrome (OM- group) and 11 with it (OM+ group). Biopsies of omental and subcutaneous fat were performed in the severely obese women during surgery, but only omental biopsies in the controls. Expression of 11ß-HSD1, glucocorticoid receptor α (GRα) and glucocorticoid receptor ß (GRß) was evaluated using real-time PCR. RESULTS: Omental 11ß-HSD1 expression was different between groups (one-way ANOVA, p < 0.01). Post-hoc analysis revealed that mean omental 11ß-HSD1 mRNA levels were higher in the OM- group compared to controls, whereas they were similar when comparing the OM+ group with lean controls. Expression of 11ß-HSD1 in subcutaneous fat was not different between OM+ and OM- groups. GRα expression in omental fat did not differ among groups or between omental and subcutaneous fat in severely obese patients. An expression of GRß was not detected. CONCLUSION: Contrary to our original hypothesis, omental 11ß-HSD1 expression is not increased in the OM+ group.

Growth velocity and final height in elite female rhythmic and artistic gymnasts.

PURPOSE: The aim of this study was to determine the impact of intensive training on adult final height in elite female rhythmic and artistic gymnasts. METHODS: The study included 215 rhythmic gymnasts (RG) and 113 artistic gymnasts (AG). RESULTS: AG were below the 50th percentile, while RG were taller than average. Final adult height was lower than target height in AG, while in RG, it exceeded target height. AG started training earlier than RG (p<0.001) and reported lower intensity of training (p<0.001). RG were taller than AG, with higher target height, greater Δ final height-target height and lower body fat and BMI (p<0.001). Using multiple regression analysis, the main factors influencing final height were weight SDS (p<0.001), target height SDS (p<0.001) and age of menarche (p<0.001) for RG, and weight SDS (p<0.001) and target height SDS (p<0.001) for AG. CONCLUSION: In both elite female RG and AG, genetic predisposition to final height was not disrupted and remained the main force of growth. Although in elite RG genetic predisposition for growth was fully preserved, in elite female AG final adult height falls shorter than genetically determined target height, though within the standard error of prediction.

Impaired pharmacokinetics of levothyroxine in severely obese volunteers.

BACKGROUND: Suppressive or replacement doses of levothyroxine (LT4) are affected by the rate and extent of the active ingredient absorbed, as well as by the lean body mass. Obesity has reached epidemic proportions worldwide and is related with many comorbidities. The aim of this study was to determine the pharmacokinetic parameters of LT4 in severely obese individuals and compared them with similar data in lean control subjects. METHODS: We studied 62 euthyroid subjects who had negative tests for anti-thyroid peroxidise antibodies (Ab-TPO). Thirty eight of these subjects were severely obese but otherwise healthy (severe obese subjects [SOS] group). Twenty-four were healthy control subjects (control group), with a body mass index of 23.3 ± 1.7 kg/m(2). Subjects received 600 µg oral sodium LT4 after an overnight fast. Serum triiodothyronine (T3), T4, and thyroid-stimulating hormone were measured at baseline. Serum T4 and T3 was measured 0.5, 1, 1.5, 2, 2.5, 3, and 4 hours after LT4 administration. RESULTS: Baseline serum T4 and thyroid-stimulating hormone concentrations were higher in the SOS group than in the control group; serum T3 was similar in the two groups. The corrected area under the curve and the maximum T4 concentration after LT4 administration were lower, whereas the time to maximum concentration from the baseline was higher in SOS than in the control group. The estimated plasma volume was higher in the SOS than in the control group. Mean serum T3 levels increased gradually during the four hours after LT4 administration in the control group. In contrast, they decreased gradually in the SOS group. CONCLUSIONS: Severely obese individuals may need higher LT4 suppressive or replacement doses than normal-weight individuals due, among other factors, to impaired LT4 pharmacokinetic parameters. The latter could be attributed to their higher plasma volume and/or to delayed gastrointestinal LT4 absorption. T4 conversion to T3 might be defective in severe obesity.

The nonthyroidal illness syndrome in the non-critically ill patient.

BACKGROUND: The nonthyroidal illness syndrome (NTIS) is a very common clinical entity among hospitalized patients and has been reported in practically every severe illness and acute or chronic stressful event. There is a large body of data associating the presence of NTIS with the severity of the underlying disease. Most of these studies concern intensive care unit (ICU) patients, whereas the non-critically ill patients outside the ICU setting are less well studied. DESIGN: We provide a review of the existing literature focusing on studies examining NTIS in non-critically ill patients and attempt to summarize the pathophysiological pathways underlying the syndrome, its prognostic role, as well as the current intervention studies mainly from a clinical standpoint. RESULTS: The aetiology of the NTIS is multifactorial and varies among different groups of patients. Experimental and clinical findings suggest that inflammatory cytokines are implicated in the pathogenesis of the syndrome, whereas recent evidence re-evaluate the role of deiodinases in thyroid hormone metabolism not only in the periphery but also in the hypothalamus and the pituitary and thus in the alterations accompanying NTIS. Clinical data examining the effectiveness of thyroid hormone supplementation in NTIS remain controversial. CONCLUSIONS: As long as there is no clear evidence of benefit from thyroid hormone replacement and until well-designed studies confirm its efficacy, thyroxine supplementation should not be recommended for the treatment of NTIS.

Abolished circadian rhythm of salivary cortisol in elite artistic gymnasts.

OBJECTIVE: The aim of this study was to evaluate the effects of intensive physical exercise and acute psychological stress during high level athletic competition as reflected on the levels of salivary cortisol in elite artistic gymnasts (AGs). DESIGN: The study included 239 AGs (142 females-97 males) who participated in the European Championship of Gymnastics in 2006 and 81 adolescents (40 females-41 males), matched for age, as controls. All athletes participated voluntarily in all or parts of the study, providing samples or data for each of the variables measured. Height, weight, body fat, lean body mass (LBM), bone age and Tanner stage of puberty were assessed and data concerning the time of thelarche, adrenarche and menarche as well as, the onset and the intensity (hours per week) of training were obtained. METHODS: Saliva samples were collected, the morning before training and in the afternoon shortly after the competition. From controls, the saliva samples were collected in the morning. Cortisol concentrations were measured using a chemiluminescence method. Acute stress was assessed using a questionnaire designed for the study. RESULTS: No difference was found between morning and afternoon salivary cortisol levels in both male and female AGs (females: AM: 15.45±7.45nmol/l vs PM: 15.73±9.38nmol/l; males: AM: 10.21±5.52nmol/l vs PM: 9.93±13.8nmol/l, p>0.05). Female AGs presented higher levels of morning salivary cortisol than female controls (p<0.05). Both male and female AGs had higher degree of psychological stress in comparison with controls (p<0.001, p<0.013, respectively). Female AGs had higher morning and afternoon salivary cortisol levels (p<0.01, p<0.01, respectively) and higher degree of stress (p<0.003) than males. CONCLUSIONS: In elite AGs the diurnal rhythm of salivary cortisol has been abolished, probably due to the strenuous training and competition conditions. Female AGs presented higher levels of morning salivary cortisol and psychological stress compared to both male AGs and female controls. The long term consequences of these modifications of the HPA axis remain to be elucidated.

Bone acquisition during adolescence in athletes.

Bone mass (BM) and skeletal size are similar in prepubertal girls and boys and double between the onset of puberty and early adult life. Sex steroids are responsible for the maturation in human skeleton, as well as for the sexual dimorphism, observed after the onset of puberty. Physical activity in childhood is critical for maximizing bone growth and thus for preventing osteoporosis during older age. Therefore, it constitutes the most effective prevention strategy available. In athletes, high-impact loading activities have been shown to improve BM, whereas in sports requiring a lean somatotype (therefore leading to a negative energy balance), the delay in skeletal maturation and pubertal development predisposes athletes to osteopenia and osteoporosis. Although the early onset of training, the continuous intensive exercise and its long duration attenuate bone acquisition, the excess mechanical load to which these athletes are exposed from a young age exerts beneficial effects on bone formation that lead to a positive net-effect on BM.

The influence of intensive physical training on growth and pubertal development in athletes.

Genetic potential for growth can be fully expressed only under favorable environmental conditions. Although moderate physical activity has beneficial effects on growth, excessive physical training may negatively affect it. Sports favoring restricted energy availability, in the presence of high energy expenditure, are of particular concern. In gymnastics, a different pattern in skeletal maturation and linear growth was observed, resulting in an attenuation of growth potential in artistic gymnasts (AG), more pronounced in males than in females. In female rhythmic gymnasts (RG), the genetic predisposition to growth was preserved owing to a late catchup growth phenomenon. In all other sports not requiring strict dietary restrictions, no deterioration of growth has been documented so far. Intensive physical training and negative energy balance alter the hypothalamic pituitary set point at puberty, prolong the prepubertal stage, and delay pubertal development and menarche in a variety of sports. In elite RG and AG, prepubertal stage is prolonged and pubertal development is entirely shifted to a later age, following the bone maturation rather than the chronological age.

Dissociation of thyrotropin and leptin secretion in acute surgical stress in severely obese patients.

BACKGROUND: During illness, thyroid parameters undergo acute changes, which are known as non-thyroidal illness syndrome, the cause of which has not been elucidated. In vitro and in vivo data demonstrate that leptin regulates the expression of thyrotropin-releasing hormone (TRH)-mRNA in the paraventricular nucleus as well as the secretion of thyrotropin (TSH) in response to fasting in humans and animals. Moreover, in healthy adults, TSH and leptin have almost identical circadian rhythms. Our aim was to investigate the secretion of leptin and TSH, and their probable interaction, during the acute stress that is induced by surgery. METHODS: We studied 18 severely obese but otherwise healthy men. All participants were admitted to the hospital in the morning after an overnight fast. On the following day, 14 of the participants underwent bariatric surgery at 0900. The remaining four participants did not undergo surgery and served as controls. Serum samples to measure the levels of TSH and leptin were collected from all participants, as follows: upon admission to the hospital (baseline values) and on the following day at 0900 and every 10 min, thereafter for 9 h. RESULTS: The serum TSH increased during the first hour after skin incision (si) and then decreased gradually throughout the rest of the observation period. In contrast, during the first hour after si, the leptin levels remained unaltered. The leptin levels then decreased and reached a nadir at 4 h and 10 min post si after which they remained constant for approximately 1 h. Thereafter, while TSH continued to decrease, leptin started to increase and reached baseline values at 9 h post si. In control subjects, the TSH and leptin profiles seemed parallel each other. CONCLUSIONS: During acute surgical stress, the secretion of TSH and leptin in severely obese men is asynchronous and causality could not be proven.

The odyssey of nontoxic nodular goiter (NTNG) in Greece under suppression therapy, and after improvement of iodine deficiency.

BACKGROUND: Nontoxic nodular goiter (NTNG) is common in endemic goiter regions. Thyroxine (T4) is often used to treat NTNG. There is little information regarding T4 treatment in regions that have recently become iodine sufficient. We studied the effect of T4 treatment on thyroid function tests in southwestern Greece (SWG), a recently iodine-sufficient area. METHODS: We studied 827 residents of SWG (group A) to determine goiter prevalence, thyroid function, and urinary iodine concentration (UIC). Group B: 385 consecutive patients with thyroid dysfunction. Of these, 89 had NTNG and followed for 10 years on T4 treatment, and 296 had hyperthyroidism. Group C: 29 patients with NTNG, treated with triiodothyronine (T3) 50 mug/day and followed for 6 months. Measurements included serum T4 and 24-hour radioactive iodine uptake (RAIU) before and at the end of T3 administration. RESULTS: The median UIC in group A was 114 microg/L. In group B (89 patients), the incidence of newly diagnosed hyperthyroidism was 5-7% per year with a cumulative percentage of 33% at the 10th year. The initial thyrotropin (TSH) was lower (0.78 +/- 0.51 mIU/L) in those who developed thyrotoxicosis compared to those who remained euthyroid (1.17 +/- 0.74 mIU/L) (p < 0.05). In 296 thyrotoxic patients, the incidence of autoimmune hyperthyroidism and toxic multi-nodular goiter (TMNG) was similar. In group C, 10/29 patients remained euthyroid and the 24-hour RAIU decreased by 49% during T3 treatment. Similarly, serum T4 decreased by 49%. In the remaining patients who developed hyperthyroidism, 24-hour RAIU and T4 were decreased by 19% and 22%, respectively. CONCLUSIONS: In SWG, a recently iodine-sufficient region, the risk of developing hyperthyroidism in patients with NTNG after administration of 100-150 microg T4 is relatively high in those whose serum TSH before T4 treatment is in the lower normal range. Therefore, T4 treatment should be avoided in these patients.

Glucose levels and insulin secretion in surgery-induced hyperglycemia in normoglycemic obese patients.

BACKGROUND: Transient hyperglycemia is commonly observed in non-diabetic subjects during surgery. We undertook this study to investigate (1) insulin secretion pattern and glucose levels during elective surgery, and (2) the role of pre-operative fasting in the development of surgery-induced hyperglycemia. METHODS: We examined 21 severely obese normal glucose tolerant patients, who underwent bariatric surgery. From the 21 operated subjects, 14 remained fasted while seven patients received 75 g glucose the preoperative night. They sampled at baseline and from the onset of operation frequently for 9 h thereafter, for measuring serum insulin and glucose. RESULTS: Hyperglycemia developed within 1 h from the onset of operation and lasted 9 h. The administration of 75 g glucose the preoperative night prevented surgery-induced hyperglycemia. Insulin profile analyzed by deconvolution analysis was similar between fasted patients and those who received 75 g glucose. Serum insulin was suppressed at the beginning of the surgery and reached baseline values 4 h thereafter. CONCLUSION: Hyperglycemia occurred within 1 h from the beginning of surgery and sustained for at least 9 h while insulin levels are suppressed or unaltered compared to baseline values in euglycemia. The administration of 75 g glucose the preoperative night prevents surgery-induced hyperglycemia without altering the profile of insulin secretion.

Treating iodine deficiency: long-term effects of iodine repletion on growth and pubertal development in school-age children.

BACKGROUND: Iodine deficiency (ID) is still a major universal health problem. Iodine deficiency disorders (IDDs) affect people of all ages, among whom the most vulnerable are children and adolescents. The aim of the present study was to assess the long-term effects on growth and pubertal development of correcting severe ID in areas of Azerbaijan between 1999 and 2000. METHODS: Iodized oil was administered orally to 293,000 children, aged 6-16 years. Among those, 364 children were randomly selected and were examined 1 year before the administration of iodized oil (Group I-neg, iodine negative) and 295 children (Group I-Rx, iodine treated) were examined 4 years (Group I-R x 4, iodine treated 4 years later; n = 173) or 5 years (Group I-R x 5, iodine treated 5 years later; n = 122) after the last dose of iodide. RESULTS: In Group I-neg the median urine iodine concentration (UIC) (mcg/L) was 36 (mean: 36.272 +/- 11.036) and increased significantly (p < 0.001) in Group I-R x 4: 188 (mean: 230.969 +/- 155.818) and in Group I-R x 5: 175 (mean: 201.176 +/- 130.369). The prevalence of goiter was 99% in Group I-neg and 2% in Group I-R x 4. Children in Group I-Rx had a greater standard deviation score (SDS) for height (-0.1364 +/- 1.279, n = 294) than children in Group I-neg (-0.5019 +/- 1.17, n = 363) (p < 0.001, t = -3.817), which was more significant for boys. SDS for weight was similar in both groups (Group I-neg: -0.17 +/- 0.78, n = 363; Group I-Rx: -0.115 +/- 0.917, n = 294). The rate of puberty development as judged by the development of breast and pubic hair was normalized in both sexes after the correction of ID. CONCLUSIONS: Our results demonstrate that long-term correction of severe ID leads to sustained improvement of linear growth accompanied by a normalization of the time of onset of pubertal development for both sexes.

Recommendations for thyroxin therapy during pregnancy.

Disorders of thyroid function are common among women of childbearing age. It is known that thyroid physiology normally alters during gestation. Clinicians, often, overlook thyroid dysfunction in pregnant women because of nonspecific symptoms and the hypermetabolic state of normal pregnancy. After all, the clinician must consider thyroid dysfunction as a possibility in pregnant women and differentiate normal physiological changes from thyroid disease. Abnormalities of maternal thyroid function can affect the fetus directly or indirectly. The fetal thyroid begins to produce thyroid hormones after the first trimester, so the critical thyroid hormones for fetal brain development must be supplied by the mother. It is of interest how sensitive the fetus is to decreases in circulating maternal thyroid hormones and in maternal thyrotoxicosis. Over recent years there has been an expansion of knowledge regarding thyroid disease in pregnancy and subsequently controversies about management of thyroid disease in pregnancy. This review focuses on maternal overt and subclinical hypothyroidism in pregnancy, suggesting guidelines for appropriate treatment for this disease due to its frequency, especially the subclinical manifestation, and the controversy that exists. It also reviews the complications in mother and fetus when hypothyroidism is untreated. On the other hand, with respect to other differing opinions, some recommendations should be given by the authors about supplying thyroxin to pregnant women with thyroid disease other than hypothyroidism.

Thyroid hormone synthesis and secretion in humans after 80 milligrams of iodine for 15 days and subsequent withdrawal.

CONTEXT: In animals, acute iodine administration results in acute intrathyroidal inhibition of iodinations followed by escape of the inhibition if the excessive iodine intake continues. In humans, the intrathyroidal nonhormonal and hormonal iodine concentration after exposure to large doses of iodine for a relatively long period of time is not known. OBJECTIVE: To determine whether, in human thyroid, administration of large doses of iodine for a relatively long time results in alterations of intrathyroidal hormonal (HI) T4 and T3 and total iodine (TI) content, as well as whether changes in serum concentration of thyroid hormones and TSH would occur after iodine administration or discontinuation. DESIGN: In 33 euthyroid patients with single thyroid nodule or hyperparathyroidism, Lugol solution (80 mg iodine) was administered for 15 d before operation. Groups of six to eight patients underwent operation 0, 5, 10, and 15 d after iodine withdrawal. TI, HI in a sample of thyroid tissue, and serum concentration of T4, T3, and TSH were measured. In 21 normal euthyroid subjects who did not undergo operation, a similar protocol was used and serial blood measurements were taken. MAIN OUTCOME MEASURE: Intrathyroidal TI, HI, and serum thyroid hormone and TSH measurements were the main outcome measure. RESULTS: Intrathyroidal HI content and serum T4 and T3 were unchanged during and after iodine discontinuation. TI was increased during iodine administration and returned to control values 5 d after discontinuation of iodine. The ratio of HI/TI was decreased and returned to control values 15 d after the iodine was discontinued. Serum TSH was increased during iodine administration and returned to control values 10 d after iodine withdrawal. CONCLUSIONS: In humans, administration of iodine for a relatively long period of time was accompanied by increased intrathyroidal TI, but no changes in HI or demonstrable increases of serum T4 and T3 were observed. It is hypothesized that the maintenance of normal intrathyroidal HI is the result of the combined inhibitory effect of iodine on thyroid hormone synthesis and on the release of T4 and T3 from the thyroid.

Capecitabine-induced hypertriglyceridemia: a report of two cases.

BACKGROUND: Capecitabine is a tumor-activated oral fluoropyrimidine with established antitumor activity in breast and colorectal cancer. Hypertriglyceridemia associated with this drug has rarely been reported in the literature. CASE REPORT: This is a report of two patients who developed capecitabine-induced severe hypertriglyceridemia, together with an increase in total cholesterol levels. The first patient developed hyperlipidemia during long-term capecitabine treatment in combination with trastuzumab for metastatic breast carcinoma (triglycerides: from 219 mgldl to 1409 mg/dl, 543% increase; cholesterol: from 239 mg/dl to 363 mg/dl, 52% increase). The second patient developed abnormalities in the lipid profile after the second cycle of chemotherapy with capecitabine and oxaliplatin for metastatic colorectal cancer (triglycerides: from 101 mg/dl to 1510 mg/dl, 1395% increase; cholesterol: from 203 mg/dl to 310 mgldl, 52% increase). An analysis of the possible underlying pathogeneic mechanisms is provided. CONCLUSION: Physicians should be aware of the possibility of dyslipidemia, particularly hypertriglyceridemia, following treatment with capecitabine.

The value of scintigraphy and ultrasonography in the preoperative localization of parathyroid glands in patients with primary hyperparathyroidism and concomitant thyroid disease.

UNLABELLED: Parathyroid scintigraphy and high-resolution ultrasonography are frequently used as preoperative localization procedures in primary hyperparathyroidism. However, when thyroid disease coexists, their diagnostic accuracy is probably abated. DESIGN: 56 patients with primary hyperparathyroidism were prospectively evaluated with parathyroid scintigraphy (with either thallium or technetium-99m agents or both) and 44 of them were also evaluated with ultrasonography. RESULTS: 33 patients (59%) had coexistent thyroid disease. Upon operation, 48 patients were found to have a solitary parathyroid adenoma and were all cured. One patient had a carcinoma and 7 had multiglandular parathyroid disease. Regarding solitary lesions, the sensitivity of parathyroid scintigraphy with Tc-agents was 97% and thallium 78%, while that of ultrasonography was 74%. The false positive rate was 2.6%, 18%, and 22%, respectively. Concomitant thyroid disease had a non-significant effect on the results of parathyroid scintigraphy and ultrasonography. The efficiency of both modalities in diagnosing multiglandular disease was low (only 3/7 patients, 43%). CONCLUSIONS: Parathyroid scintigraphy, in conjunction with Sestamibi or Tetrofosmin, constitutes the most sensitive localizing technique as regards solitary lesions. Ultrasonography is also useful in confirming scintigraphic findings, offers more precise anatomic information, and is valuable in the evaluation of concomitant thyroid disease. The complementary use of parathyroid scintigraphy and ultrasonography is beneficial and efficacious in areas with high prevalence of thyroid disease. The value of these modalities is considerably lower in multiglandular disease.