Molecular aetiology of nodular goitre -- consequences for therapy?

Up to 15 % of the adult German population display an enlarged thyroid gland and up to 30 % present thyroid nodules. Iodine deficiency is the most important factor in the etiology of nodular goiter. Insulin-like growth factor-I is overexpressed in thyroids in severely iodine deficient areas. There is evidence that iodolactones are mediators of thyroid hormone autoregulation. However familial and twin studies demonstrated a genetic component in the etiology of nodular goiter. Linkage analysis identified two chromosomal regions (MNG-1, Xp 22) in multinodular goiter. Other possible candidate genes or markers such as TG, TPO, NIS, PDS and TSH-R were not identified. Nodular goiter certainly comprises a number of genotypes. TSH receptor mutations result in activation of the cAMP cascade. Cells with a constitutively activated cAMP cascade have an increased growth advantage due to their TSH independent cAMP stimulation. Alimentary iodine supply should be the first choice in primary prevention of nodular thyroid disease in iodine deficient areas, because prevalence of nodular goiter is negative correlated with individual iodine status in epidemiological surveys. Surgical removal of nodular goiters should include nearly the hold thyroid tissue to avoid recurrent goiter.     

Relationship between thyroid function and carotid atherosclerosis in patients on maintenance hemodialysis

Objective To investigate the changes of thyroid function and carotid atherosclerosis in patients on maintenance hemodialysis (MHD). Methods A total of 110 stable MHD patients undergoing hemodialysis for at least three months were enrolled in the study. Serum free-T3 (FT3), free-T4 (FT4) and thyroid stimulating hormone (TSH) concentrations were measured by electrochemiluminescence．Plasma levels of homocysteine (Hcy) and C-reactive protein (CRP) were detected. Clinical data and biochemical indicators were collected. These patients were divided into thyroid dysfunction group and euthyroidism group. Prevalence of atherosclerosis was detected by carotid ultrasonography. The associations between the changes of thyroid function and carotid atherosclerosis were analyzed by Logistic regression model. Results Among these 110 patients, 42 (38.18%) patients had thyroid dysfunction. Hcy and CRP concentrations were significantly higher in thyroid dysfunction group than those in euthyroidism group (P＜0.05). The intima-media thickness, number of plague and arteriostenosis of carotid were higher in thyroid dysfunction group than those in euthyroidism group (P＜0.05). Multivariate logistic regression analysis showed that increased Hcy and CRP, decreased serum FT3 were independent risk factors for carotid atherosclerosis. Conclusions Thyroid dysfunction with low serum FT3 is frequently found in MHD patients. In MHD patients, FT3 is closely correlated to carotid atherosclerosis.     

血清TSH浓度与结节性甲状腺肿合并甲状腺癌关系的研究

目的探讨术前血清促甲状腺素(TSH)浓度与结节性甲状腺肿合并甲状腺癌的相关性。方法回顾性分析632例结节性甲状腺肿患者的TSH浓度与合并甲状腺癌间的关系。根据TSH值不同,将患者分成5组进行统计分析。结果结节性甲状腺肿合并甲状腺癌患者血清TSH浓度为(2.10±1.38)mU/L,较未合并者的(1.51±0.98)mU/L高(P<0.000 1);随着血清TSH浓度的升高,合并甲状腺癌比率升高(P=0.023 5),TSH0.3～0.9 mU/L组为9.91%、0.9～1.7 mU/L组为12.37%、1.7～4.8 mU/L组为20.09%、>4.8 mU/L组为27.27%。肿瘤直径<2 cm组、2～4 cm组和>4 cm组比较,直径较大的TSH浓度更高(P=0.018 6)。TNM分期T3～T4期患者TSH浓度高于T1～T2期患者(P=0.030 6)。结论术前血清TSH浓度可能是预测结节性甲状腺肿合并甲状腺癌风险的一个指标。     

Thyroid gland volume and serum concentrations of thyroid hormones in chronic renal failure

Thyroid gland volume, ultrasonically determined, and thyroid function were investigated in 40 patients with chronic renal failure (33 of these on hemodialysis) and 40 sex-, age- and weight-matched healthy controls. None had thyroid autoantibodies or a clinically detectable goiter. The median thyroid gland volume was significantly elevated in the uremic patients: 24 ml (range 8-43 ml) compared with the healthy controls 17 ml (range 10-22 ml) (p less than 0.005). The serum concentrations of thyroxine (T4), triiodothyronine (T3), free thyroxine index (FT4I) and free triiodothyronine index (FT3I) were significantly decreased in uremic subjects compared with the controls. The serum concentration of thyrotropin did not differ significantly between patients and controls. None of the thyroid function variables correlated with thyroid gland volume. In conclusion, thyroid gland volume was increased in patients with chronic renal failure. The alterations in thyroid hormone concentrations could, however, not explain this finding.     

Evaluation of Thyroid Disease in Kidney Transplantation Candidates: Management and Follow-up

Introduction

Diagnosis of thyroid disease is fundamental in the evaluation of patients awaiting kidney transplantation. We analyzed the incidence of thyroid disease in patients with end-stage renal disease (ESRD) and evaluated its evolution before and after kidney transplantation.

Patients and Methods

Between January 2000 and May 2008, we evaluated 323 candidates for kidney transplantation. In all patients, serum concentrations of free triiodothyronine, free thyroxine, and thyroid-stimulating hormone were determined and a ultrasonography of the neck was performed. Patients with thyroid cancer were considered eligible for kidney transplantation after at least 2 years since treatment.

Results

One-hundred-four patients with ESRD (44%) had functional or morphologic changes in the thyroid gland. Forty-one patients (17.4%) underwent fine-needle aspiration cytology; 3 demonstrated showed papillary carcinoma; 3, follicular adenomas; 8, uncertain cytologic lesions; and 27, a nodular goiter. Seventeen patients underwent surgery. Six of 11 patients with thyroid cancer underwent transplantation: two patients underwent laterocervical lymph node dissection because of local recurrence within 2 years after successful transplantation; the other 4 patients are alive with a functioning graft. Of the 184 transplant recipients, 10 underwent surgery to treat thyroid disease: 8 with multinodular goiter, 1 with micropapillary carcinoma, and 1 with follicular adenoma. All 10 patients are alive with a well-functioning graft and no signs of disease recurrence.

Conclusions

Thyroid diseases are common in patients with ESRD. Early diagnosis and treatment significantly decreased morbidity and mortality in patients awaiting transplantation.     

Follow-Up After Surgery for Benign Nodular Thyroid Disease: Evidence-Based Approach

Background

There is no consensus on what constitutes appropriate methodology and timing for follow-up of patients after surgery for benign nodular disease.

Methods

A systematic review of the medical literature using evidence-based criteria was used to address the following four issues: (1) How often should patients who have undergone thyroidectomy for the treatment of benign nodular goiter be followed, and what constitutes appropriate follow-up? (2) What is the most appropriate method for detecting recurrent nodular thyroid disease? (3) Does thyroid hormone administration prevent recurrent nodular thyroid disease? (4) Does iodine administration prevent recurrent nodular thyroid disease?

Results

Altogether, 742 articles were found in MEDLINE using a keyword search strategy; we then narrowed them to 23 articles. There were a total of four articles with Level I data, five articles with Level II data, one article with Level III data, and 13 articles with Level IV or retrospective data.

Conclusions

Based on the available data, it is our recommendation that patients undergoing thyroid lobectomy for benign nodular thyroid disease should be followed with an annual physical examination, neck ultrasonography, and serum thyroid-stimulating hormone (TSH) measurement. Patients undergoing total thyroidectomy should be followed with an annual physical examination and a serum TSH measurement. Routine thyroxine and/or iodine supplementation may be useful for preventing recurrence in patients from iodine-deficient regions.

     

Repeated surgeries on the thyroid gland in nodular euthyroid goiter

Medical histories of 214 patients hospitalized with diagnosis "recurrent nodular goiter" were studied retrospectively. Complex clinical, laboratory and instrumental examination was carried out in all the patients. Comparative analysis demonstrated that in the structure of recurrent goiter nodular colloid form dominated (84.1%), only in 42.1% cases repeated surgeries were indicated. Other patients (15.9%) were the ones underwent surgery for other thyroid diseases (hypertrophied form of autoimmune thyroiditis, follicular adenoma, thyroid cysts, thyroid cancer). Inadequate surgery and prophylactic therapy with iodine drugs were the main causes of recurrent goiter. Adequate iodine prophylaxis (potassium iodide 100-200 mg per day), complex examination of patients, correct indications for primary surgery and adequate surgical volume, valuable postoperative therapy (iodine drug, LT-4 if it is necessary) permit to reduce the risk of recurrent nodular (multiple-nodular, diffuse-nodular) goiter. Ways of researches for improvement of diagnosis, prophylaxis and treatment results of "recurrence nodular goiter" are projected.     

术前TSH水平与甲状腺结节良恶性关系

目的：探讨血清促甲状腺激素（TSH）浓度与甲状腺结节良恶性的关系。 方法：回顾性分析近3年间收治的421例甲状腺结节患者的临床资料,其中结节性甲状腺肿347例,甲状腺癌74例。比较良恶性甲状腺结节患者血清TSH浓度差异,并分析TSH浓度与甲状腺结节的恶性风险以及甲状腺癌不同病理类型与血清TSH浓度的关系。 结果：甲状腺癌患者血清TSH浓度明显高于结节性甲状腺肿患者[（2.57±3.32）mIU/L vs. （1.67±2.90）mIU/L]（P<0.05）;甲状腺结节的恶性风险随血清TSH浓度的升高而逐渐升高,当TSH>5 mIU/L时,恶性率为50.0%;甲状腺癌不同病理类型间血清TSH浓度无统计学差异（P>0.05）。 结论：甲状腺结节恶性风险随血清TSH浓度的升高而增加,术前血清TSH测定可以作为甲状腺结节良恶性判断的一个辅助性指标。     

Studies on nonthyroidal illness after heart surgery

The concentrations of pituitary hormones (TSH and PRL), thyroid hormones (free-T4 and free-T3), thyroid hormone binding protein (TBG) and lipids (TG and FFA) in the blood were measured in order to examine the physiology of nonthyroidal illnesses that occurred as a result of heart surgery as well as their effects on the pituitary and thyroid glands. The subjects of the study consisted of 30 adults with congenital and acquired heart disease. Blood concentrations of TSH, PRL, free-T4, free-T3, and TBG decreased, and those of FFA increased, on the 2nd day following surgery. On the 2nd day following surgery, the decrease in the concentrations of free-T4 and free-T3 in the blood were considered due to a decrease in secretion of T4 from the thyroid gland, as well as due to a decrease in the activity of iodothyronine 5'-deiodinase in the peripheral organs. In the 3rd week following surgery, the concentrations of these items returned to their original values on the day prior to surgery.     

Lack of nocturnal serum thyrotropin (TSH) surge in patients with chronic renal failure undergoing regular maintenance hemofiltration: a case of central hypothyroidism

Thyrotropin (TSH) secretion was evaluated in a group of patients with chronic renal failure (CRF) undergoing regular maintenance hemofiltration and in normal controls. The study group included 68 patients (39 males and 29 females, age range 39-73 years, mean: 53 years). In all patients blood was drawn at 08:30-09:00 h; in 20 patients the nocturnal (24:00-02:00 h) serum TSH peak was also evaluated; 12 patients underwent stimulation test with synthetic TSH-releasing hormone (TRH). TSH was measured by an ultrasensitive immunoradiometric assay. CRF patients showed a significant decrease in serum total and free thyroxine and triiodothyronine concentrations, which in a substantial proportion of subjects were below the lower normal limit. Serum reverse triiodothyronine and thyroxine-binding globulin values did not differ in the two groups. Despite this trend of thyroid hormones to decrease, no patient had supranormal TSH values as in primary hypothyroidism. While the mean morning TSH concentrations of CRF patients did not differ from those of controls, the mean nocturnal values were significantly reduced in CRF (1.0 +/- 0.2 vs 3.2 +/- 0.4 mU/l, p less than 0.0005) and the nocturnal serum TSH surge was not observed in 18 of the 20 patients (90%) in whom it was evaluated. The mean serum TSH peak value after TSH-releasing hormone (TRH) administration was also reduced in CRF patients, and the TSH response to TRH was blunted in 3 out of 12 patients (25%). The results of this study demonstrate a major impairment of TSH secretion in CRF, which baseline TSH measurements in the morning and the evaluation of the TSH response to TRH may not reveal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Selenium Deficiency and Thyroid Function in Acute Renal Failure

The lethality of acute renal failure exceeds 50% due to multiorgan dysfunction. In such critically ill patients a reduction of thyroid hormone concentrations without clinical symptoms or laboratory evidence of hypothyroidism frequently occurs. Selenium has recently been shown to play a major role in thyroid hormone metabolism. The aim of this study was to investigate the possible influence of selenium on thyroid hormone metabolism in acute renal failure. Changes in thyroid metabolism were related to the severity of multiorgan failure and to the clinical course. Thyroxine (T4), tri-iodothyronine (T3), free-T4, free-T3, thyrotropin (TSH), serum creatinine, and plasma selenium concentrations in 28 patients (mean age 60 ± 13) with acute renal failure and multiple-organ dysfunction syndrome were determined initially, and every 3 days after hospital admission. The plasma selenium concentration was found to be reduced compared to normal controls (32 ± 14 vs. 70–120 μg/L). T4 (56 ± 15 nmol/L, normal range 64–148), T3 (1.31 ± 0.38 nmol/L, normal range 1.42–2.46), free-T3 (3.1 ± 1.0 pmol/L, normal range 4.7–9.0), and free-T4 (10.8 ± 4.0 pmol/L, normal range 10.3–25.8) values were low in 50–70% of the patients at the time of presentation. Plasma TSH concentrations were within the normal range (0.59 ± 0.79 mU/L, normal range 0.25–3.1), and no clinical symptoms of hypothyroidism were observed. T4 concentration was higher in patients who survived acute renal failure compared to nonsurvivors (62 ± 22 vs. 51 ± 16 nmol/L, p < 0.05). Plasma selenium concentration was lower in patients with a severe organ dysfunction syndrome (36 ± 10 vs. 29 ± 19 μg/L) and correlated with the number of organ failures in these patients (r = –0.247, p < 0.05). T4 and free-T4 values paralleled decreasing selenium concentrations (r = 0.35, p < 0.05). Thyroid hormone levels were reduced in patients with acute renal failure without an increase in TSH. An increase in T4 concentrations became apparent during treatment and may be related to a favorable outcome in acute renal failure. Thyroid hormone concentrations paralleled plasma selenium levels, indicating a possible influence of selenium on thyroid function in acute renal failure.     

Urinary Iodine Concentrations Should Be Monitored to Diagnose Some Thyroid Gland Diseases in Heart Transplant Recipients

Background

According to the World Health Organization, iodine excreted in urine is a measure of its supply. According to the International Council for Control of Iodine Deficiency Disorders (ICCIDD), the urinary iodine (UI) should be >100 μg I per 1 liter of urine. Severe deficiency (SID) is diagnosed when UI is <50 μg/L and a moderate deficiency (MID) when UI is <100 μg/L.

Materials and Methods

UI analysis among 32 heart transplant recipients (26 men and 6 women); of overall mean age of 50.4 ± 12.6 years was performed using the modified Program Against Micronutrient Malnutrition method, a spectrophotometric measurement based on the Sandell-Kolthoff reaction. Results were compared with those of thyroid stimulating hormone (TSH; μIU/mL), of free tri-iodothyronine (FT3; pg/mL), and thyroxine (FT4; ng/dL).

Results

The average UI among the whole group was 126.4 ± 109.6 μg/L. SID occurred in 12 patients (37.5%) and MID in 4 (12.5%); namely, mean UI of 17.0 ± 9.6 and 79.5 ± 5.6, respectively. In the other 16 patients (50%), the average UI was high, namely, 220.1 ± 72.1 IU/mL. TSH, FT3, and FT4 in the whole group were within normal ranges. However, FT4 values significantly differed when SID and MID patients were compared with those displaying the recommended UI: 0.8 ± 0.2 and 0.9 ± 0.1 versus 1.1 ± 0.2 respectively (P < .05). We noted decreased values of TSH in 5 patients (15.6%) and of FT3 or FT4 in 6 subjects (18.8%).

Conclusion

There exists significant iodine deficiency among heart transplant recipients. Measurements of urinary iodine together with thyroid gland hormones may be essential to prevent thyroid gland disturbances in these patients.     

结节性甲状腺肿术后残留与复发的临床分析

目的探讨结节性甲状腺肿术后复发的原因及预防措施。方法回顾性分析本院2005年1月至2009年7月收治的967例结节性甲状腺肿患者中70例结节性甲状腺肿手术后复发情况、再手术方式及疗效。术后均予以TSH抑制剂治疗,随访0.5～5年。结果初发单侧腺体结节性肿手术47例,同侧复发20例,对侧复发13例,双侧复发14例;初发双侧腺体结节性肿手术21例,术后单侧复发14例,双侧复发7例;既往手术史不详2例,均为双侧复发。单侧腺体复发行侧叶次全切除或全切除术,双侧腺体复发行双侧甲状腺次全切除或一侧全切除、对侧次全及全切除术。复发性结节性甲状腺肿再次手术治疗的并发症发生率明显高于首次手术。结论结节性甲状腺肿术后复发率高,与其病理特点、手术方法、术后TSH抑制剂治疗不规范有关。规范手术方式、术后规律服用TSH抑制剂治疗可能减少复发率。     

Thyroxine therapy in benign thyroid nodules

Levothyroxine (LT4) treatment in benign thyroid nodules is a controversial management. The favorable response varies between 10-60%, being, in some studies, comparable between treated and untreated groups. The aim of this study was to evaluate the response of uninodular goiter at the LT4 treatment, in comparison with untreated patients. The study group (S) included 53 patients diagnosed with nodular goiter, treated with LT4 for 1 year. 26 patients with nodular goiter, age and sex-matched, untreated, constituted the control group (C). All patients were from a minor iodine deficient area. The including criteria were euthyroidism, single nodule, solid (ultrasonography), cold (Scintigraphy), and benign (FNAB). After 1 year mean nodular volume had a significant decrement in both groups, higher in group S (35%: from 7.8 to 5.2 mL, p = 0.0098) than in group C (25%: from 8.4 to 5.9 mL, p = 0.026). Linear regression showed a slight correlation between the nodular decrement and the initial volume (r = 0.23): the responders percentage was higher in nodules with a volume < 5 ml than in those with volume > 5 ml (51.5% vs o 19.6%, p < 0.0001). The evolution of treated nodules seamed to be better than of the untreated ones, but the differences were only slightly significant. We believe that the evolution of thyroid nodules under LT4 treatment can be influenced by the iodine supply, since in most of the studies from minor iodine deficiency regions (Europe, South America) the response is better than in regions with sufficient iodine supply (North America). Knowing the potential side effects of LT4 therapy, this kind of management of benign thyroid nodules should be reserved to selected cases.     

Thyroidectomy or radioiodine? The value of ultrasonography and cytology in the assessment of nodular lesions in Graves' hyperthyroidism

Although diffuse toxic goiter is a classical feature of Graves' disease (GD) nodular goiters are occasionally found in some patients. The aim of the present study was to investigate the ultrasonographic and corresponding cytological manifestations in GD patients with nodular lesions to decide on a therapeutic strategy. Twenty-seven consecutive GD patients with nodular goiter were included in this study (21 women and six men, mean age 41.2 years, range 22-77 years). All underwent thyroid ultrasonography and fine-needle aspiration cytology. Of the 27 patients eight underwent surgical intervention because papillary thyroid carcinoma or follicular neoplasm was diagnosed by cytology; five of these were shown to have papillary thyroid carcinomas. Ultrasonography revealed the malignant nodules to be hypoechogenic, heterogeneous, and with ill-defined margins in four of these five thyroid cancers, whereas the remaining sonogram showed a cystic change and cauliflower-like tumor formation with microcalcification. The volume and maximal diameter of cancerous nodules were significantly larger than those of benign nodules. In conclusion our results reveal that ultrasonography and fine-needle aspiration cytology are reliable and quick methods for diagnosing nodular goiters in GD patients. If thyroid neoplasms are found ablative therapy with thyroidectomy is indicated instead of radioactive iodine.     

全民普遍食盐加碘后广西地区甲状腺疾病谱的变迁

目的分析实行全民普遍食盐加碘前后广西沿海、山区等不同碘环境下甲状腺疾病谱变迁的特点,探讨普遍食盐加碘对甲状腺疾病谱的影响。方法收集广西南宁、桂林、百色及北海4城市的解放军三。三医院、解放军一八一医院、广西右江民族医学院附属医院及北海市人民医院1991年1月至2006年12月期间经手术治疗的甲状腺疾病患者共5998例,所有病例均有病理诊断并检测了尿碘水平;另检测同期1000位甲状腺正常人群的尿碘水平作对照。分析普遍食盐加碘前后碘环境的改变与甲状腺疾病谱变迁的关系。结果普遍食盐加碘后,结节性甲状腺肿患者的构成比较加碘前下降（尸〈0．05）,而毒性结节性甲状腺肿、慢性淋巴细胞性甲状腺炎及甲状腺乳头状癌患者的构成比较加碘前增高（P〈0．053;同时,结节性甲状腺肿、毒性弥漫性甲状腺肿、毒性结节性甲状腺肿、慢性淋巴细胞性甲状腺炎及甲状腺乳头状癌患者尿碘水平较加碘前明显增高（P〈0．05）,并且甲状腺疾病患者的尿碘水平高于对照组（P〈0．05）,甲状腺疾病患者及对照组的尿碘水平均较加碘前增高（P〈0．05）。结论全民普遍食盐加碘10年来,广西所调查地区平均尿碘水平及甲状腺疾病谱均发生了明显变化,碘过量可能是导致毒性结节性甲状腺肿、慢性淋巴细胞性甲状腺炎、慢性淋巴细胞性甲状腺炎合并乳头状癌及甲状腺乳头状癌发病率增高的环境因素之一。     

Incidental thyroid carcinoma in patients with Graves' disease

BACKGROUND: The clinical significance of incidental thyroid carcinoma in patients with Graves' disease is uncertain. METHODS: The prevalence of incidental thyroid carcinoma was determined in patients with Graves' disease who underwent surgery from 1990 to 2007 and was compared with patients with nontoxic nodular goiter or toxic multinodular goiter who underwent surgery during the same time period. RESULTS: Of the 93 patients who underwent thyroidectomy for Graves' disease, 2 patients (2.2%) had an incidental papillary carcinoma: .4 and .5 cm in size. Neither patient developed recurrent disease after 3 and 13 years of follow-up evaluation. The prevalence of incidental thyroid cancer was 3.6% and 6.2% in patients with nontoxic nodular goiter and toxic multinodular goiter, respectively (P = not significant). CONCLUSIONS: The prevalence of incidental thyroid carcinoma in patients with Graves' disease is comparable with patients with nontoxic or toxic goiter. Incidental thyroid carcinomas in patients with Graves' disease were papillary microcarcinomas of no clinical consequence.     

Thyroid cancer associated with adenomatous goiter: An analysis of the incidence and clinical factors

We evaluated the incidence of thyroid cancer in patients with adenomatous goiter and investigated the clinical factors distinguishing patients with occult thyroid cancer, defined as a tumor size smaller than or equal to 10 mm, from those with clinical thyroid cancer, defined as a tumor size larger than 10 mm. Of 835 patients with histologically confirmed adenomatous goiter, 256 (30.7%) also had thyroid cancer, being occult in 137 patients and clinical in 119 patients. There was no correlation between the maximum size of the thyroid cancer tumor and the age of the patient, and the percentage of patients with thyroid cancer in each group was not influenced by age. There were no significant differences in age, sex, the serum concentrations of free triiodothyronine, free thyroxine, thyrotropin, and thyroglobulin, or the urinary iodine creatinine ratio. The frequency of calcified lesions being detected by ultrasonography (US) and/or neck X-ray in the patients with clinical thyroid cancer was significantly greater than that in those with occult cancer at 83%vs 57%, respectively (P<0.0001). This study disclosed a high prevalence of thyroid cancer associated with adenomatous goiter, and the results suggest that a considerable number of associated carcinomas remain occult. The detection of calcification in the thyroid gland is one of the surgical indications for patients with adenomatous goiter.     

结节性甲状腺肿合并甲状腺癌25例

目的：探讨结节性甲状腺肿中甲状腺癌的临床特征和预后。方法：回顾性分析手术治疗结节性甲状腺肿合并甲状腺癌２５例临床资料。结果：２５例结节性甲状腺肿合并甲状腺癌,男６例,女１９例,年龄１２～６５（３６．８±１３．１）岁,占同期手术治疗３９５５例结节性甲状腺肿的０．６３％。术前、术中诊断甲状腺癌的占３２％,６８％为术后病理检查发现。甲状腺微小癌占４８％。结论：结节性甲状腺肿合并甲状腺癌预后较好。不能简单地认为结节性甲状腺肿是良性病变而忽略对其的处理,也不应过分强调甲状腺癌在治疗结节性甲状腺肿中的地位随意放宽手术指征,或扩大手术。     

Mediastinal goiter; report of a case

A 76-year-old female was admitted to our hospital because of an abnormal shadow on chest computed tomography (CT) which showed the tumor extending from left lower end of the thyroid to the aortic window along the left side of the trachea, indicating the retrosternal goiter. Serum thyroid stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) were within normal ranges. The tumor was resected through cervical collar incision and median sternotomy. The pathological diagnosis was an adenomatous goiter. The patient was discharged without complications.