Diagnostic scintigraphy in postoperative staging and follow-up of differentiated thyroid carcinoma

In the last decade new knowledge has been acquired on the cellular and molecular biology, growth and prognostic factors responsible for the clinical evolution and response to therapy of differentiated thyroid carcinoma. At the same time, the procedures for early diagnosis of small (occult), poorly aggressive thyroid tumors as high resolution neck sonography combined with fine needle aspiration have greatly advanced. This led to reconsider the definition of the most adequate management with a more frequent use of combined radiochemotherapy and surgery for aggressive forms and simple lobectomy for occult tumors. These progressive changes in the therapeutic approach required the diversification of corresponding follow-up protocols of differentiated thyroid carcinoma. The efforts of radiologists and nuclear physicians in particular, were focused on two sectors: 1) the early visualization of metastases no longer able of radioiodine uptake where, therefore, this radionuclide cannot be used for diagnosis or therapy; 2) the diagnosis of metastases in patients undergoing subtotal thyroidectomy. In these cases, 131I has no role in imaging and the determination of serum TG is not very significant. To assess the diagnostic role of nuclear medicine in these situations, the main characteristics of radioiodine scintigraphy with particular reference to the use of high 131I doses and of recombinant human TSH, the diagnostic potentialities of scintigraphy with the most common oncotropic tracers other than 131I were analyzed.     

Ultrasound diagnosis of C-cell carcinoma of the thyroid

Ultrasound screening in 9 and 21 members, respectively, of two families affected by familial C-cell carcinoma, as well as sonographic findings in 6 patients with sporadic medullary carcinoma of the thyroid (MCT), are reported. Unilateral and bilateral tumor nodules were identified by sonography in 12 of a total of 13 patients with MCT (n = 9) or local tumor recurrence following thyroidectomy (n = 4); one carcinoma, 3 X 6 mm in diameter, was missed. Nine of the 12 (75%) were clinically occult, nonpalpable C-cell carcinomas. The smallest occult MCT correctly diagnosed by ultrasound had a diameter of 4 mm. A positive correlation was found between the sonographically determined tumor mass (number/size of nodules/metastases) and the plasma calcitonin level. Pheochromocytomas were diagnosed by ultrasound as part of a multiple endocrine neoplasia (MEN IIa) in two patients with MCT. The echomorphologic findings of the intrathyroid C-cell carcinomas and their metastases display characteristic but nonspecific features. Sonographic findings on these tumors should therefore not be interpreted without consideration of plasma calcitonin assays.     

Clinical evaluation of tumor characteristics predisposing serum thyroglobulin to be undetectable in patients with differentiated thyroid cancer

This study delineates tumor characteristics which predispose serum thyroglobulin (TG) to be undetectable in patients in spite of persistent or recurrent differentiated thyroid cancer. Three hundred seventy four thyroid carcinoma patients with completed thyroid ablation were investigated by means of conventional diagnostic procedures (131 iodine total-body scan, x-ray, TG determination) and, in addition, with high-resolution sonographic study of the neck. Sensitivity of TG for the detection of metastases amounted to 83% under TSH stimulation and 50% under thyroxine (T4) treatment. Specificity proved to be 95% under TSH stimulation and 99% under T4 treatment. Common features of the tumors associated with false-negative TG determinations (n = 16) were papillary histologic characteristics, manifestation in lymph nodes of the neck or mediastinum, and small size. It is therefore necessary for the early detection of persistent or recurrent papillary cancer metastases to perform in addition to 131 iodine scans high-resolution sonography of the neck in combination with the determination of TG serum concentrations under endogenous TSH stimulation.     

颈动脉体瘤的超声诊断

目的：分析颈动脉体瘤的灰阶及彩色多普勒超声图像特征,以提高诊断的准确率。方法：回顾性分析18例颈动脉体瘤灰阶超声及其中11例彩色超声的图像资料。并与易引起误诊的多种病变作对比分析。结果：B超显示肿块均位于颈动脉分叉处,边界清楚,内回声略低,较均匀,常包绕颈部,内、外动脉,颈动脉夹角增宽,肿瘤内血流丰富,均为动脉,17个颈动脉体瘤超声诊断正确,其诊断准确率为94．4％,结论：超声检查是颈动脉体瘤安全,可靠的诊断方法。     

Radioiodine therapy in differentiated thyroid carcinoma

Radioiodine therapy has been successfully applied for over 50 years in the management of differentiated thyroid carcinoma. Careful patient preparation and selection of the optimal dose of radioiodine to be administered are two factors of major importance in the course of management. Main indications for 131I therapy are the ablation of residual thyroid tissue after thyroidectomy, the treatment of locoregional recurrence and distant metastases which involve almost exclusively the lung and bones. A controversial aspect is that of patients with high serum TG levels but negative whole body 131I scintigraphy for whom there is no general agreement. Other controversial aspects involve ablation therapy as the selection of patients to be treated and the control of its efficacy. The cost and possible adverse side-effects of 131I therapy require a careful analysis of prognostic factors in each patient candidate for the treatment.     

The significance of I-131 treatment of metastatic thyroid-carcinoma

The benefit of I-131 therapy of metastatic differentiated thyroid carcinoma is controversial. To evaluate usefulness of I-131 therapy for metastatic differentiated carcinoma, 83 patients were chosen from 276 patients with differentiated thyroid carcinoma who were operated at Nagasaki University Hospital since 1960 according to the following criteria; (i) thyroids totally removed, (ii) existence of metastases at total thyroidectomy, (iii) the cause of death related to thyroid carcinoma if the patient died. The usefulness of I-131 therapy was evaluated by analysis of survival during 10 years following total thyroidectomy. In patients without remote metastases, the survivors and nonsurvivors were 37 and 2 in those without I-131 therapy (Group I), and 11 and 1 in those with I-131 therapy (Group II), respectively. There was no significant difference between the two groups. In patients with remote metastases, the survivors and non survivors were 9 and 1 in I-131 treated patients who had I-131 accumulation in the metastases with tracer doses (Group III-1), 1 and 11 in I-131 treated patients without I-131 accumulation in metastases with tracer doses (Group III-2), and 4 and 6 in non I-131 treated patients whose metastases were not examined for I-131 accumulation (Group IV), respectively. The prognosis was best in Group III-1 and followed by Group IV and Group III-2 in this order in patients with remote metastases. There was no significant difference in age and sex among the groups and in pathological findings of carcinoma. These results suggest that I-131 therapy may be useful for patients with remote metastases which accumulate I-131 with tracer doses but not for those patients who do not accumulate I-131 and that I-131 accumulation in metastases with tracer doses may be of prognostic significance.     

Death from differentiated thyroid carcinoma: retrospective study of a 40-year investigation

Differentiated thyroid carcinoma (DTC) usually has a good prognosis, but sometimes the course of the disease results in death. The aim of the present study was to assess the effect of some variables in time to death on fatal cases in our series. A total of 83 patients with DTC who died between 1958 and 1998 from differentiated thyroid cancer were retrospectively analyzed with respect to gender, age at diagnosis, histology, percentage of (131)I uptake by postoperative thyroid remnant, site of tumor growth, and its (131)I uptake, metastases and time to death. Univariate analysis revealed a significantly shorter time to death in local recurrence when comparing local lymph node metastases and distant metastases even if neither show (131)I uptake. Multivariate analysis revealed that age at diagnosis was the most important factor in conditioning the time to death. In conclusion, in those patients who died from DTC an older age at diagnosis and presence of local recurrence influenced the time to death independently of (131)I uptake.     

Chest computed tomography (CT) in patients with micronodular lung metastases of differentiated thyroid carcinoma

Forty thoracic CT scans have been performed on 27 patients with micronodular lung metastases of differentiated thyroid carcinoma. Lung nodules were visualized in 14 out of 19 patients (78%) with functioning lung metastases, although their chest X rays were normal. However, only a small number of peripheral micronodules can be visualized by CT scan since the central micronodules remain undistinguishable from adjacent vessel structures. A close relationship has been found between the number of micronodules and the thyroglobulin (Tg) serum level. In patients previously treated by 131I for proven lung metastases and who had no uptake for several years, but in whom Tg remained detectable in the serum, CT scans have shown micronodules in 7 of the 13 patients with normal chest X rays. The present data suggest that these nodules are mainly a result of fibrosis. CT scanning appears to be an important complementary tool with regard to 131I whole body scintigraphies in the radiologic diagnosis of lung nodules and in the assessment of radioiodine therapy.     

Diagnostik des Schilddrüsenkarzinoms

Most thyroid cancers are well differentiated, grow slowly, and have a good prognosis. They account for less than 1% of all malignancies with an incidence of 3 per 100,000. Clinical presentation of thyroid cancer is a late event induced by local infiltration and the development of cervical lymph nodes. The problem of early diagnosis of thyroid cancer is the high prevalence rate of thyroid nodules in the German population (30%) and the low malignancy rate (1–2%). Diligent work-up is necessary including evaluation of risk factors, routine ultrasonography of the thyroid, thyroid scintigraphy and in all hypoechogenic, cold nodules >1 cm diameter fine-needle aspiration as well as fine-needle aspiration in all rapidly growing nodules. Calcitonin determination in all thyroid nodules and if slightly elevated a pentagastrin stimulation test is recommended for early detection of medullary thyroid carcinoma. A familial variant occurs in 25% of medullary thyroid carcinomas which can be confirmed by RET mutation analysis. Further family studies identify asymptomatic gene carriers who can be cured by early prophylactic thyroidectomy, which improves the overall mortality rate and prognosis.     

Clinical examination and 131 Cs scanning in the diagnosis of cold nodules of the thyroid (author's transl)]

The usefulness of 131Cs scanning in preoperative diagnosis of 131I cold nodules of the thyroid that present no clear clinical sign of malignancy is discussed. The results of clinical examination of 283 thyroid nodules, associated in 139 cases with 131Cs scanning, are correlated with the histologic nature. In nodules that were classifided as cold, warm or hot in the 131Cs scan, the incidence of malignancy was 2.6, 12.3 and 25%, respectively. In the nodules that, on the basis of clinical examination, were classified as probably benign, dubious or suspected for malignancy, the incidence of cancer was, respectively, 3.6, 26.3 and 72.7%. Malignancy ocurred in 16 of 144 patients that were selected for surgical treatment only on the basis of clinical data and in 17 of 139 patients that were selected on the basis of clinical examination associated with 131Cs scanning. The accuracy of clinical preoperative diagnosis of thyroid cold nodules does not seem to be significantly improved by association of 131Cs scanning.     

分化型甲状腺癌术后131I清甲疗效相关影响因素分析

目的:探讨分化型甲状腺癌术后131I清甲疗效相关影响因素。方法:回顾性分析分化型甲状腺癌术后131I清甲治疗患者128例临床资料,总结包括年龄、性别、病理分型、手术切除方式、肿瘤转移、肿瘤转移部位、血清促甲状腺激素（TSH）水平及131I治疗时间等临床特征对疗效的影响。结果:对不同性别、年龄、病理分型及肿瘤转移有无进行分组比较,分化型甲状腺癌患者术后131I治疗临床疗效差异无统计学意义（P＞0.05）;而行甲状腺全切、肿瘤颈部淋巴结转移、血清TSH水平20~40mIU/L及131I治疗时间≤6个月组分化型甲状腺癌患者术后131I清甲临床疗效显著优于其他分组,差异有统计学意义（P＜0.05）;手术切除方式、血清TSH水平及131I治疗时间是影响分化型甲状腺癌术后131I治疗效果独立因素。结论:分化型甲状腺癌术后131I清甲疗效与手术切除方式、血清TSH水平及131I治疗时间具有相关性。     

99mTc-甲氧异腈显像在分化型甲状腺癌转移灶诊断中的临床应用

目的:探讨99mTc-甲氧异腈(MIBI)显像在分化型甲状腺癌(DTC)转移灶诊断中的临床应用价值.方法:72例接受131I治疗的分化型甲状腺癌随访患者,以甲状腺球蛋白增高阈值＞10ng/ml为标准分为实验组(n=35)和对照组(n=37),常规行131I全身扫描(WBS),同时以99mTc-MIBI作为显像剂行核素肿瘤显像.以核素显像感兴趣区(ROI)技术,测定放射性(T/NT)比值,进行半定量分析;比较99mTc-MIBI显像及131I全身显像在诊断甲状腺癌转移灶灵敏性、特异性、准确性上的差异.结果:实验组,99mTc-MIBI显像和131 I全身显像T/NT比值分别为3.24 ±0.43和5.35 ±0.32,有明显差异;对照组T/NT比值分别为1.31 ±0.18和1.26±0.25,无明显差异;两种方法诊断分化型甲状腺癌转移灶的灵敏性、特异性、准确性分别为24.52％、64.28％、32.83％和92.45％、57.14％、85.07％.结论:99mTc-MIBI显像诊断分化型甲状腺癌转移灶灵敏性及准确性均低于131I全身显像,特异性无明显差异,但99mTc-MIBI显像可作为131I全身显像阴性分化型甲状腺癌随访方法的有益补充.     

Indium-111-labelled octreotide scintigraphy in the diagnosis and management of non-iodine avid metastatic carcinoma of the thyroid

Treatment of differentiated thyroid cancer is a success of modern medicine with the use of radioiodine ((131)I). However, a significant proportion of thyroid cancers may be non-iodine avid. Thyroid tumours are known to express somatostatin receptors. Octreotide, an analogue of somatostatin, can be combined with a radioactive isotope, such as (111)In-DTPA(0) to visualise tumours with high concentrations of somatostatin receptors. We assessed 18 patients with histologically proven metastatic or locally recurrent non-iodine avid thyroid carcinoma to determine the usefulness of (111)In-DTPA(0) octreotide scintigraphy compared to conventional radiology in diagnosing sites of metastasis. The diagnosis of metastatic disease was made using conventional radiology and all had prospective scintigraphy using (111)In-DTPA(0)octreotide. Of the 18 patients, 14 had octreotide-positive scans. In eight, the octreotide scans identified the same sites of metastases as conventional radiology, that is, were concordant. In nine patients, conventional radiology showed more extensive disease than revealed on the octreotide scans. In one patient with widespread bone metastases, octreotide gave a more detailed assessment of metastatic disease than conventional radiology. These data indicate that (111)In-DTPA(0)octreotide imaging for patients with non-iodine avid carcinoma of the thyroid may be a useful diagnostic and staging tool. One patient with Hurthle cell carcinoma metastatic to bone and a positive octreotide scan has been treated with (90)yttrium-labelled octreotide.     

Well Differentiated Thyroid Carcinoma: Current Treatment

Well differentiated thyroid carcinoma (WDTC) is a relatively common malignancy accounting for an estimated 37,000 thousand cases in the United States in 2009 [1]. WDTC also has a generally high 5 year survival rate that correlates with age. Papillary thyroid carcinoma (PTC) greater than 1 cm is best managed by total thyroidectomy. Thyroid lobectomy and isthmusectomy may be adequate for unifocal PTC less than 1 cm in patients without negative prognostic factors. Central compartment and possible lateral neck dissections should be performed when nodal metastases are present in the respective nodal basins. Post-operatively, radioactive iodine ablation with ¹³¹I followed by thyroid stimulating hormone (TSH) suppression is indicated in certain patients to improve locoregional control and reduce recurrence.     

超声对低分化和未分化甲状腺癌的诊断价值

目的 探讨超声对低分化甲状腺癌(PDTC)和未分化(间变性)甲状腺癌(UTC)的诊断价值.方法 应用彩色多普勒超声对22例PDTC和UTC的甲状腺形态、大小、回声、边界、内部砂粒、血流分布等声像图表现及其内部血流状况进行观察,并与手术、活组织病理检查病理结果对照;扫查颈部及气管食管沟区淋巴结.根据甲状腺双叶或单叶弥漫性病变及局部淋巴结的超声表现,结合临床表现,判断甲状腺病变的性质.结果 术前或活组织病理检查前超声检出甲状腺单叶肿物16例,左甲9例,右甲7例.双叶肿物6例.超声提示UTC 2例,甲状旁腺癌1例,慢性淋巴细胞性甲状腺炎1例,其余提示甲状腺恶性肿瘤.结论 超声检查可提高PDTC和UTC的检出率和诊断率.     

Tc-99m depreotide imaging of I-131-negative recurrent metastatic papillary thyroid carcinoma

The detection of radioiodine (I-131)-negative metastases of differentiated thyroid carcinoma (DTC) has been hitherto successfully tried by the well-known synthetic somatostatin analogue indium-111-labeled DTPA-octreotide (In-111 pentetreotide). The objective of this study was to evaluate the usefulness of scintiscan with the newer synthetic somatostatin analogue Tc-99m depreotide, in the restaging of papillary thyroid carcinoma (PTC) with detectable serum thyroglobulin (Tg) levels and negative I-131 whole-body scan (WBS). Whole-body planar and cervico-thoracic tomographic scintigraphy (single-photon emission tomography-SPET) with Tc-99m depreotide was performed in a 68-year-old male patient suffering from PTC stage III, with a mild increase in serum Tg levels coupled with a recent negative I-131 WBS. The findings were compared with those of neck ultrasonography (US) and computerized tomography (CT). Nodal neck dissection and histopathology provided the definitive diagnosis. Tc-99m depreotide scanning revealed foci of cervical lymph node metastases, which did not accumulate I-131. The findings were in accordance with neck US and CT. Histopathology established the diagnosis of metastatic cervical lymph node PTC. Lymph node immunoreactivity was positive for the somatostatin receptor subtypes 2, 5 and 3. Scintigraphy with Tc-99m depreotide could prove a useful adjunct to the armamentarium for the follow-up of PTC, especially in the setting of detectable serum Tg and negative I-131 WBS.     

A case of lung carcinoma induced by radioactive iodine given for disseminated thyroid carcinoma

We report a case of a patient who at the age of 32 developed a squamous carcinoma arising in the thorax. At 7 years of age he had received aggressive treatment with ¹³¹I for a thyroid carcinoma with multiple pulmonary metastases. Radiation induced malignancy, in sites such as the bone marrow or bladder, after ¹³¹I therapy is recognized; however, tumours arising in the thorax after such treatment have not been described.     

Primary papillary thyroid carcinoma previously treated incompletely with radiofrequency ablation

Radiofrequency ablation (RFA) recently has been applied to benign thyroid nodules, mainly for the cosmetic reasons, and limited cases of local recurrences or focal distant metastases of well-differentiated thyroid cancer, in the high-risk reoperative condition or for the palliative purpose. But no report has been made on the RFA for primary thyroid cancer to date. We report on a patient with primary papillary carcinoma of thyroid gland who had undergone RFA before the cytological diagnosis of malignancy, later referred and treated with robotic surgery successfully. We can learn the following lessons from our case; (1) the RFA for operable primary thyroid malignancy should be avoided, because of the possibility of remnant viable cancer and undetectable nodal metastasis, and (2) robotic or endoscopic thyroid surgery may be a feasible operative method for benign or malignant thyroid nodules previously treated with RFA.     

甲状腺低分化滤泡状癌30例临床分析

背景与目的：甲状腺低分化滤泡状癌较少见,但有其一定的临床特征和发展规律。本研究探讨其临床特征、治疗效果及预后,旨在提高对本病的认识。方法：回顾分析30例低分化滤泡状癌的临床资料。用Kaplan-Meier法统计生存率,用log-rank检验模型对患者年龄、性别、肿瘤大小、外侵程度、治疗方式和手术切除程度等可能的预后因素进行分析,用t检验分析两组数据之间是否有显著性差异。结果：3、5和10年的总生存率分别为32．2％、25．1％和12．5％;3、5年累积肿瘤复发率分别为37．6％和48．0％。3、5年颈淋巴结转移率为57．6％、68．2％,3、5年远处转移率为82．5％和86．9％。根治性切除原发灶及颈部转移灶可显著降低肿瘤复发(χ^2=6．59,P=0．01),改善生存率(χ^2=12．40,P=0．00)。伴有静脉瘤栓的肿瘤复发率明显高于其他患者(χ^2=4．62,P=0．03)。接受I治疗的远处转移患者的生存时间显著长于未行I治疗的患者(χ^2=12．25,P=0．00)。结论:甲状腺低分化滤泡状癌的远处转移率高,预后差,远处转移是影响预后的主要原因。手术切除是提高局部控制和改善预后的关键,I治疗远处转移有效,可延长生存时间。     

空洞型肺转移瘤的CT表现及与原发灶病理类型的关系(英文)

目的探讨空洞型肺转移瘤的 CT 表现及其与原发灶病理类型的关系。方法报告空洞型肺转移瘤40例131枚,分析其 CT 表现并与原发灶病理类型进行对比。结果全部空洞瘤灶均与肺多发实性结节共存。共有泡样空洞41枚,不规则空洞33枚,囊样空洞26枚,小环形空洞31枚。壁厚度均匀者61枚,不均匀者70枚。瘤灶直径<15mm 者44枚,15～25mm 者66枚,25～40mm 者1枚,>40mm 者4枚,洞壁厚度<4mm 者69枚,4～15mm 者44枚,>15mm 者18枚。空洞型瘤灶多见于腺癌(22例)与鳞癌(13例),二者在 CT 表现上各有一定特征。空洞型瘤灶的发生与其在肺内的部位无关。结论空洞型肺转移瘤的 CT 表现具有一定特点,并与原发灶病理类型有关。