Expression of Vascular Endothelial Growth Factor and Presence of Angiovascular Cells in Tissues from Different Thyroid Disorders

Background

Vascular endothelial growth factor (VEGF) is involved in tumor angiogenesis and other pathophysiological processes.

Materials and methods

We studied the localization of VEGF in human thyroid tissues to clarify its involvement in proliferative processes in a variety of thyroid disorders. Immunohistochemical analysis using purified rabbit polyclonal anti-human VEGF or anti-human CD34 antibody and a streptavidin–biotin peroxidase complex detection system was performed on 58 tissue specimens from 53 patients with different thyroid disorders and 5 normal thyroid glands.

Results

Vascular endothelial growth factor was not detected in normal thyroid follicular cells. However, some thyroid tumor cells expressed VEGF in the cytoplasm (papillary carcinoma, 10/18; follicular carcinoma, 1/3; medullary carcinoma, 2/2; follicular adenoma, 3/11; adenomatous goiter, 2/4). In benign follicular adenoma and adenomatous goiter, weak expression of VEGF was found in small areas of the tumor, whereas in malignant thyroid tumors, it was strongly expressed in many cells. However, VEGF was not expressed in anaplastic carcinoma, malignant lymphoma, or Graves’ disease. Angiovascular cells stained with CD34 antibody in tissues from different thyroid disorders reflected statistically significant differences in papillary carcinoma, follicular adenoma, and Graves’ disease compared with normal thyroids, and such cells showed a trend toward increases in medullary carcinoma and adenomatous goiter. In contrast, low vascularity was observed in anaplastic carcinoma, malignant lymphoma, and follicular carcinoma.

Conclusions

Because VEGF probably functions as a hypoxia-inducible angiogenic factor, overexpression of this mediator, concomitant with hypervascularity, may be induced more strongly in malignant thyroid tumors, which need more oxygen to proliferate, than in benign follicular tumors. However, neither VEGF nor CD34 was expressed in anaplastic thyroid carcinoma, which is an extremely poorly differentiated malignant tumor. CD34 but not VEGF was expressed in the hyperplastic thyroid tissues of Graves’ disease composed of nontransformed cells. Thus, the expression of VEGF concomitant with CD34 is suggested to reflect both the transformation and differentiation state of malignant tumors.     

Ornithine decarboxylase activity and polyamine levels in human thyroid tumor tissue

Production of polyamines such as putrescine (PUT), spermidine (SPD) and spermine (SPM) primarily from ornithine by ornithine decarboxylase (ODC) is correlated with cell proliferation. Polyamine levels and ODC activities were measured to determine the degree of biological malignancy in 186 thyroid tumor tissues. Carcinoma showed significantly higher ODC activity and higher levels of PUT, SPD and SPM than benign tumors. PUT levels showed 2.28 nmol/mg protein in anaplastic carcinoma, 0.66 in papillary carcinoma, 0.11 in follicular adenoma, 0.06 in adenomatous goiter and 0.04 in normal thyroid tissue. Anaplastic and papillary carcinomas showed higher PUT/SPD and SPD/SPM ratios than benign tumors. Poorly differentiated carcinoma showed significantly higher PUT level and PUT/SPD and SPD/SPM ratios than well differentiated carcinoma. No correlation was found among polyamine levels, ages and sex in papillary carcinoma. In female patients with papillary carcinoma, no significant difference in polyamine levels was observed between patients above and below 50 years old. These results suggest that ODC activity and polyamine levels may provide useful information to determine the degree of biological malignancy of thyroid tumors.     

Fluorine-18-fluorodeoxyglucose positron emission tomography in the preoperative assessment of thyroid nodules in an endemic goiter area

BACKGROUND: The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the preoperative assessment of suspicious thyroid nodules. METHODS: A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq (18)F-FDG. Standard uptake values (SUVs) were calculated. RESULTS: A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. (18)F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 +/- 2.2, 3.7 +/- 1.9, 1.6 +/- 0.3, 1.2 +/- 0.2, and 0.9 +/- 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used. CONCLUSIONS: Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. (18)F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded.     

Fine needle aspiration biopsy of thyroid nodules

The clinical value of the fine needle aspiration of thyroid nodules was evaluated by comparing preoperative cytology to subsequent pathology in 109 patients undergoing thyroidectomy. Preoperative cytology was reported as insufficient cellular material (31 patients), benign goiter (27 patients), follicular neoplasm (22 patients), thyroiditis (12 patients), suspicious for papillary carcinoma (nine patients), Hurthle cell neoplasm (five patients), medullary carcinoma (one patient), lymphoma (one patient), and metastatic adenocarcinoma (one patient). Operative findings demonstrated that the overall sensitivity of fine needle aspiration in diagnosing thyroid neoplasia (carcinoma or adenoma) was 88% and its specificity was 80%. Operation verified the cytologic diagnosis of medullary carcinoma, lymphoma, metastatic adenocarcinoma, and seven of nine papillary carcinomas. Of the five patients with an aspiration biopsy diagnosis of Hurthle cell neoplasm, three patients had carcinoma and one had an adenoma. Four carcinomas and 12 follicular adenomas were found in patients with a cytologic diagnosis of follicular neoplasm. Thyroiditis was confirmed at operation in all 12 patients with this diagnosis on fine needle aspiration. One carcinoma was found in the 27 patients with benign goiter diagnosed on cytology. Fine needle aspiration is a valuable tool that can lead to earlier diagnosis and treatment of thyroid cancer. However, a negative aspiration does not supplant good clinical judgement in determining the need for thyroidectomy.     

CD10在甲状腺疾病中的表达及意义

目的研究CD10在甲状腺疾病中的表达及意义。方法收集70例甲状腺良、恶性病变组织,其中15例滤泡性腺瘤、15例腺瘤性甲状腺肿、30例乳头状癌和10例滤泡性癌。采用免疫组织化学的方法检测CD10在上述病变中的表达。结果9例滤泡型乳头状癌中,7例表达CD10,CD10阳性率为77％。10例滤泡性癌中,8例表达CD10,阳性率为80％。而在滤泡性腺瘤和腺瘤性甲状腺肿及21例普通型乳头状癌组织中CD10均不表达。CD10在滤泡型乳头状癌和滤泡性癌中的阳性率显著高于滤泡性腺瘤和腺瘤性甲状腺肿中的阳性率（P〈0．01）。结论对CD10表达的检测有助于对甲状腺滤泡性癌和滤泡型乳头状癌的诊断。     

Hyperthyroidism and concurrent thyroid malignancies

In a 17-year period 1848 patients with hyperthyroidism were operated on. Fourteen (0.76%) had a coexisting thyroid malignancy. Preoperative scintiscan and pathologic diagnoses were compared: 10 malignancies were in cold nodules, two were unidentifiable preoperatively due to small size, and two were in hot areas. Five patients had papillary cancer, four follicular, three anaplastic, and two medullary. Patients with uninodular toxic goiter had a low rate of associated malignancy (0.27%, 3/1108). In contrast, patients with multinodular toxic goiter had an incidence of 1.63% (11/676). No patient with Graves' disease (n = 64) had a carcinoma. Extensive use of fine-needle aspiration biopsy enabled preoperative diagnosis in a majority of the cases (9/14, 64%). We conclude that the incidence of coexisting thyroid malignancy and hyperthyroidism is rare in our endemic iodine-deficiency goiter area.     

Observer variation of encapsulated follicular lesions of the thyroid gland

Although histologic definition of follicular thyroid lesions is readily available, application of the diagnostic criteria and personal experience may lead to disagreement among pathologists. To investigate interobserver variation in assessment of encapsulated follicular lesions, eight pathologists (four American and four Japanese) reviewed the same hematoxylin and eosin-stained slide of each of 21 cases of thyroid lesions showing encapsulation and follicular growth pattern. In 10% of the cases, there was complete agreement. At least seven pathologists agreed on the diagnosis in 29% of the cases, and at least six in 76% of the cases. American and Japanese pathologists agreed among themselves in 33% and 52% of cases, respectively. The frequency of diagnosis of adenomatous goiter among Japanese pathologists (31%) was considerably higher than that among American pathologists (6%). In contrast, the frequency of diagnosis (25%) of papillary carcinoma among American pathologists was considerably higher than that (4%) among Japanese pathologists. Our analysis revealed three main factors affecting observer variation: 1) interpretation of the significance of microfollicles intimately related to capillaries within the tumor capsule, 2) evaluation of what constituted the type of nuclear clearing indicative of papillary carcinoma, and 3) absence of clear morphologic criteria for separation of adenomatous goiter and follicular adenoma. To reduce observer variation of encapsulated follicular lesions, it will be necessary to provide more explicit criteria for diagnosis.     

CD10表达在甲状腺滤泡性癌和滤泡型乳头状癌诊断中的作用

目的研究CD10表达在甲状腺滤泡性癌和滤泡型乳头状癌诊断中的作用。方法收集70例甲状腺良、恶性病变组织，其中包括15例滤泡性腺瘤、15例腺瘤性甲状腺肿、30例乳头状癌（包括9例滤泡型乳头状癌）和10例滤泡性癌，采用免疫组织化学方法检测CD10在上述组织中的表达。结果9例滤泡型乳头状癌中，7例表达CD10（77．8％），10例滤泡性癌中8例表达CD10（80．0％）；CD10在非滤泡型乳头状癌、滤泡性腺瘤、腺瘤性甲状腺肿和正常甲状腺组织中均不表达。结论对CD10表达的检测有助于对甲状腺滤泡性癌和滤泡型乳头状癌的诊断。     

Pathohistologic and immunohistochemical characteristics of thyroid carcinoma

Numerous pathohistologic criteria, difficulties and pitfalls in the process of diagnosing of thyroid carcinoma are discussed. Benign hyperplastic papillae may be present in colloidal cystic goiter and hyperplastic goiter. These structures are lined by cells with normochromatic nuclei and do not disturb the thyroid tissue architecture. Papillae in papillary thyroid carcinoma have cells with ground-glass, hypochromatic nuclei. Follicles inspissated in capsula of follicular or even colloidal adenoma may be evaluated as capsular invasion--diagnostic feature of follicular carcinoma. Undifferentiated thyroid carcinoma is sometimes similar to fibrosarcoma and reveal cellular pleomorphism, anaplasia and numerous foci of necrosis. Medullary thyroid carcinoma with scanty stromal amyloid, its papillary variant and carcinoid-like histologic type consist of oval cells with eosinophilic cytoplasm and dark nuclei.     

Nuclear DNA content and prognosis in Hürthle cell tumours of the thyroid gland

The prognostic value of nuclear DNA content in Hürthle cell tumours of the thyroid was studied in 23 patients with more than 10 years follow up. Eleven of these neoplasms were classified as Hürthle cell carcinoma and 12 as adenoma. DNA measurements in morphologically identified single tumour cells were performed either on fine needle aspiration biopsy material or on histological sections from the primary tumours. The nuclear DNA content identifies those patients with a good versus a bad prognosis. These results correlate well with the findings in earlier studies about papillary, follicular and medullary thyroid tumours.     

CCR7在甲状腺乳头状微小癌中的表达及临床意义

目的探讨CCR7在甲状腺乳头状微小癌中表达情况及其与甲状腺乳头状微小癌临床病理特征的关系。方法采用免疫组织化学S-P法检测31例甲状腺乳头状微小癌,34例直径>1 cm的甲状腺乳头状癌、34例结节性甲状腺肿以及12例甲状腺乳头状微小癌对侧正常甲状腺组织中CCR7的表达情况。结果 CCR7在甲状腺乳头状微小癌及直径>1 cm甲状腺乳头状癌中的表达阳性率均为100%,其差异无统计学意义(P>0.05),而在结节性甲状腺肿和正常甲状腺组织中CCR7的表达阳性率分别为64.7%和33.3%,与甲状腺乳头状微小癌相比差异有统计学意义(P<0.05)。CCR7的表达与患者性别、年龄、侵犯甲状腺被膜及淋巴结转移均无关(P>0.05)。结论 CCR7的表达在甲状腺乳头状微小癌和直径>1 cm甲状腺乳头状癌中均呈高表达,两者可能具有相同的生物学特性,两者均易发生颈淋巴结转移,均需要进行颈淋巴结(中央区)清扫。     

Unsuspected nonmedullary carcinoma of the thyroid in patients with hyperparathyroidism

All patients with hyperparathyroidism seen in a large referral military hospital within a twenty month period underwent neck exploration by one of us (HN). Three patients were found to have an unsuspected solid thyroid nodule measuring 0.5 to 1.5 cm. All were widely excised by thyroid lobectomy and isthmectomy and found to be follicular or papillary carcinoma of the thyroid. These three patients join thirty-one previously reported clinical cases documenting an association between parathyroid adenoma and nonmedullary carcinoma of the thyroid. Because of the high potential for malignancy in this clinical setting, we urge careful examination and palpation of the thyroid gland during neck exploration for hypercalcemia in order to detect and cure "early" malignancies of the thyroid.     

Differentiated thyroid cancer--peculiar morphological and clinical forms

The most common clinical presentation of differentiated thyroid cancer (DTC), consisting of papillary and follicular adenocarcinoma (with their histological variants), is the solitary thyroid nodule. A review of the literature is performed in order to describe particular forms of DTC, in terms of incidence, diagnosis and treatment: occult carcinoma, carcinoma on aberrant thyroid tissue, "functional" thyroid carcinoma and familial non-medullary carcinoma. A particular interest is shown to the coexistence of malignancy with benign thyroid diseases, such as goiter, hyperthyroidism and Hashimoto's thyroiditis, as well as parathyroid adenoma. In conclusion, the authors emphasize that the association of carcinoma with benign thyroid conditions is not rare and it substantiate an aggressive approach in regard to diagnosis and treatment, increasing the indication for surgery and, moreover, for total thyroidectomy.     

桥本病并存甲状腺结节外科治疗的临床分析

目的探讨桥本病并存甲状腺结节的临床特征和外科诊治经验。方法对1985年 1月至2004年12月因发现甲状腺结节行外科手术,术后经病理证实为桥本病的299例患者的临床特征进行分析。结果桥本病并存甲状腺癌52例(17．4％),甲状腺腺瘤103例(34．4％),结节性甲状腺肿17例(5．7%),甲状腺功能低下11例(3．7％),甲状腺功能亢进7例(2．3％)。1995年以前桥本病与甲状腺癌并存患者6例,占同期手术治疗的桥本病65例的9．2％;1996年以后桥本病与甲状腺癌并存患者46例,占同期手术治疗桥本病234例的19．7％(P<0．05)。并存甲状腺癌中乳头状癌 35例,滤泡状癌11例,混合性癌4例,黏膜相关淋巴瘤1例,全组中隐匿性甲状腺癌17例,占并存甲状腺癌的32．7％。手术方式由患者具体情况并结合术中冰冻结果确定,包括一侧或双侧甲状腺全切除或次全切除、部分切除或活检术。结论桥本病与甲状腺癌、甲状腺腺瘤并存率高,其发病率近年来有明显增高趋势;应警惕桥本病并存甲状腺肿瘤特别是隐匿性甲状腺癌的可能性。     

Classification, staging, prognostic factors and risk factors in thyroid carcinoma

Thyroid carcinomas arise from follicular cells (papillary, follicular, Hurthle, anaplastic), parafollicular cells (medullary) and stroma (lymphoma, sarcoma). Gradation and prognostic factors are different for every one of histological type. Most patients with papillary and follicular thyroid cancer have an excellent prognosis. At the other extreme is anaplastic thyroid cancer whose usual mean survival can be measured in months. Exposure to external radiation and living in endemic goiter area increase the frequency of thyroid cancer. Medullary thyroid carcinoma is often familial and may occur in associations with the multiple endocrine neoplasia syndromes.     

Hyalinizing trabecular adenoma--an uncommon thyroid tumor frequently misdiagnosed as papillary or medullary thyroid carcinoma

BACKGROUND: Hyalinizing trabecular adenoma (HTA) is an uncommon benign thyroid tumor that can present as a solitary thyroid nodule, a prominent nodule in a multinodular goiter, or as an incidental finding in a thyroidectomy specimen. The clinical significance of the lesion is that it is frequently misdiagnosed as papillary carcinoma on fine-needle aspiration cytology or as papillary or medullary carcinoma on histopathological section. We reviewed our recent experience with 7 patients diagnosed with HTA. METHODS: Fine-needle aspiration biopsy was performed in 7 patients presenting with a solitary thyroid nodule (n = 4) or a multinodular goiter (n = 3). The patients underwent total thyroidectomy (n = 6) or hemithyroidectomy (n = 1). RESULTS: In 4 patients, the preoperative cytology was suggestive of papillary carcinoma, in 2 patients suspicious, and in 1 patient positive for papillary carcinoma. On histopathological section, 2 patients had a microscopic HTA, 2 patients had HTA in 1 or 2 nodules of a multinodular goiter, and 3 patients had HTA in a solitary nodule. Except in 1 patient, who had a microscopic focus (3.2 mm) of papillary carcinoma, there was no evidence of malignancy in the surgical specimens on permanent histopathological section. CONCLUSIONS: Although HTA is a rare condition of the thyroid, the surgeon needs to be aware of this entity to be able to better discuss the pathological findings with the patient, particularly since some pathologists and endocrinologists believe that HTA may represent a malignant neoplasm of low metastatic potential.     

Measurement of plasma calcitonin gene-related peptide (CGRP) level in patients with thyroid disease

To elucidate the pathophysiology of CGRP in patients with medullary thyroid carcinoma (MTC), we measured the plasma CGRP level in patients with thyroid disease employing RIA. The plasma CGRP level (normal level 12.7 pg/ml) was elevated in all five preoperative patients with MTC, ranging from 128 pg/ml to 2010 pg/ml, and in ten of 17 postoperative patients who indicated possible recurrence. On the other hand, CGRP levels showed low frequencies of elevation in 96 patients with other thyroid tumors (anaplastic carcinoma, malignant lymphoma, follicular adenoma and adenomatous goiter), subacute thyroiditis, chronic thyroiditis and Graves' disease. Provocation test (calcium gluconate plus pentagastrin) in 12 MTC patients showed that, although the CGRP level fluctuated in parallel with the calcitonin level, the elevation rate (maximum level after administration/basal level) of CGRP was lower than that of calcitonin. Particularly, the rate of elevation of CGRP in three virulent and advanced patients with poorly differentiated MTC was below 2.0, while that in nine patients with well-differentiated MTC ranged from 2.8 to 23.3. These results suggest that CGRP may be a humoral marker of MTC and is possibly related to the degree of malignancy.     

Flow cytometric DNA analysis of thyroid carcinoma

Abnormal DNA content has been considered as an additional criterion for determining the biological behavior of a tumor. Flowcytometric DNA analysis was done on 121 patients with thyroid carcinoma encountered during the period between 1975 and 1987. Tumor tissues were sampled from paraffin-embedded blocks and the histology of thyroid carcinoma found to consist of 91 papillary, 23 follicular, 2 medullary, 1 squamous cell and 4 anaplastic carcinomas. The incidence of aneuploidy in thyroid carcinoma was 7.4 per cent (9 patients) while that of diploidy was 92.6 per cent (112 patients). The aneuploid specimens consisted of 6 papillary, 1 follicular, 1 medullary and 1 anaplastic carcinomas and, of 4 anaplastic carcinoma patients with subsequent death within 6 months, only 1 was aneuploid. As an indicator of proliferative potential, S-phase fraction (SPF) was also determined by flow cytometry, but this could not be used as an independent prognostic factor. The aneuploid patients showed a significantly decreased survival rate (p<0.01). Thus, although DNA measurement proved useful for predicting the survival of aneuploid patients, there is some discrepancy between DNA content and the biological behavior of the tumor.