18F-FDG-PET in the follow-up of thyroid cancer

Differentiated thyroid cancer is a rare tumour with an incidence of 4 - 9/100,000/year. For preoperative assessment of thyroid nodules, ultrasonography (US) and US-guided fine needle aspiration biopsy are the methods of choice to detect thyroid cancer. The value of preoperative fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) in differentiating malignant from benign nodules, especially in cases of follicular proliferation, has not yet been evaluated. After thyroidectomy and radioiodine remnant ablation, several methods are used to follow patients with differentiated thyroid cancer, including serum thyroglobulin, ultrasonography of the neck, iodine-131 (131I) whole body scintigraphy (WBS) and scintigraphy with nonspecific tracers such as technetium-99 m ((99m)Tc) Tetrofosmin or Sestamibi. Whereas the specificity of 131I-WBS is high, sensitivity is low, especially if one takes into account that only two-thirds of recurrences or metastases store iodine. With the introduction of 18F-FDG in oncology, it is also used for the detection of local recurrences and metastases of differentiated thyroid cancer. Elevated thyroglobulin but negative 131I-WBS belongs to the 1a indications for 18F-FDG-PET in oncology according to the German Consensus Conference 2000. The sensitivity for detecting 131I-negative metastases with 18F-FDG-PET can be increased by elevated thyroid-stimulating hormone (TSH) after withdrawal of thyroid hormone therapy or after intramuscular injection of recombinant TSH. Most of the 131I-negative metastases demonstrate 18F-FDG uptake, which represents rapid tumour growth and poor differentiation, whereas most of the 131I-positive metastases are 18F-FDG negative. The combination of 131I-WBS and 18F-FDG-PET leads to an increase in the detection rate to more than 90 - 95 % in cases of elevated thyroglobulin, because well- and less-differentiated cancer cells may be present in one patient. In rare cases, a recurrent tumour or metastasis may accumulate 131I as well as 18F-FDG. In these patients, it may be possible that well- and less-differentiated cells are present in one metastasis. The early use of 18F-FDG-PET in patients with elevated thyroglobulin, especially in the case of negative 131I-WBS, changes the therapeutic strategy in up to half of the patients (surgery, external radiation).     

Diagnostic capabilities of I-131, TI-201, and Tc-99m-MIBI scintigraphy for metastatic differentiated thyroid carcinoma after total thyroidectomy

We investigated the diagnostic capabilities of I-131, Tl-201, and Tc-99m-MIBI (hexakis-2-methoxyisobutyl- isonitrile) scintigraphy for thyroid cancer metastases after total thyroidectomy over the entire body and for every locus before and after thyroid bed ablation. After total thyroidectomy of thyroid cancer, 36 cases were subjected to I-131 treatment 64 times. They consisted of 17 men and 19 women with 31 papillary carcinomas and 5 follicular carcinomas. Their ages were 22--75(an average of 60.5+/-12.3) years. I-131 scintigraphy(I-131), Tl-201 scintigraphy(Tl-201), and Tc-99m- MIBI scintigraphy (Tc-99m-MIBI) were performed. We defined the metastases as those cases in which serum thyroglobulin (Tg)increased significantly or in which we were able to prove the lesions on CT (computed tomography), MRI (magnetic resonance imaging) or bone scintigram. Three radiology medical specialists visually evaluated each scintigram and calculated the sensitivity, specificity, and likelihood ratio. For whole-body sensitivity, both Tl-201 and Tc-99m-MIBI were high before ablation and I-131 was high after ablation. Before ablation, the negative likelihood ratio was less than 0.1 for Tl-201 and Tc-99m-MIBI, while the positive likelihood ratio was more than 10 for Tl-201. After ablation, the positive likelihood ratio for I-131, Tl-201, and Tc-99m-MIBI was more than 10. The sensitivity of the mediastinum was appropriate, except for I-131 before ablation, and the sensitivity of the lung before and after ablation was inferior for either tracer. The specificity of the cervix for I-131 before ablation was markedly deteriorated, but it increased after ablation.     

131I治疗老年分化型甲状腺癌淋巴结转移的疗效评价

目的 探讨131I治疗老年分化型甲状腺癌淋巴结转移（LMDTC）的疗效.方法 对33例老年分化型甲状腺癌术后合并淋巴结转移进行131I治疗,并采用B超、CT、131I显像及Tg变化综合判断疗效.结果 33例老年分化型LMDTC,131I治疗后有27例淋巴结消除或缩小,有效率为81.8％（27/33）.结论 131I治疗老年分化型甲状腺癌淋巴结转移有较好的疗效.     

Thyroid follicular neoplasm: Analysis by fine needle aspiration cytology,frozen section,and histopathology

We performed a retrospective analysis of follicular neoplasm data obtained from frozen section examinations of thyroid nodules. A total of 5,660 patients underwent preoperative neck ultrasonography and fine‐needle aspiration cytology (FNAC), surgical treatment, and follow‐up at a medical institute. Patients with papillary thyroid microcarcinoma were excluded from this study. In 971 cases, frozen section examination was performed during the surgical treatment of follicular neoplasm that was diagnosed via FNAC. Thyroid malignancies were histologically confirmed in 25.1% of cases (244/971). Among the patients with papillary thyroid carcinoma, 45 were diagnosed with the follicular variant of papillary thyroid carcinomas (27.4%). The diagnostic sensitivity of frozen section for the nonfollicular variant of papillary thyroid carcinoma was better than that for the follicular variant of papillary thyroid carcinoma (89.1% versus 78.9%; P = 0.1023). For 12 cases the diagnosis was atypical follicular adenomas. The diagnostic accuracy of frozen section in cases of follicular neoplasm was 76.9% with a sensitivity of 84.8% and a specificity of 98.9%. In conclusion, our analysis revealed high rates of accuracy when using frozen tissue sections for early diagnosis and treatment of follicular neoplasm; thus, an early decision to extent of surgery prevents a risky follow‐up surgery. Diagn. Cytopathol. 2010;38:801‐805. © 2009 Wiley‐Liss, Inc.     

Suture granuloma mimicking recurrent thyroid carcinoma on ultrasonography

Although high resolution ultrasonography (US) is helpful in the differentiation of suture granulomas from recurrent thyroid cancer in most cases, a definite diagnosis cannot always be made. We report a case that mimicked recurrent thyroid cancer on US and 2-[fluorine-18] fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), but diagnosis of a suture granuloma was confirmed by a US-guided fine needle aspiration biopsy (FNAB). In order to avoid unnecessary operations, the differential diagnosis between postoperative suture granulomas and recurrent cancer is important.     

Distant metastases in differentiated thyroid carcinomas: a clinical and pathologic study

Of 514 patients with differentiated thyroid carcinoma treated between 1970 and 1987, 34 (6.6%) had distant metastases. Twelve patients died of their distant metastases; eight of these patients died within 5 years from the time of initial diagnosis. Death from cancer was most frequent in the seventh decade. The metastases were most often found in the lungs and bones. In the fatal group, pleural, brain, and pericardial metastases were noted. Local recurrences were found only in 24% of these 34 patients. Histologic types of primary thyroid tumors and metastatic tumors were reexamined and classified using our criteria, which were mainly based on the World Health Organization nomenclature and currently obtained pathologic observations of thyroid tumors. In 31 thyroid tumors, the surgical specimens were available for review. Twenty-four tumors were papillary and seven were follicular. Of the 24 papillary carcinomas, nine were follicular, eight were well-differentiated, and seven were trabecular. On the other hand, the seven follicular carcinomas consisted of four well-differentiated, two solid, and one oxyphilic. The majority of the thyroid tumors showed an extrathyroidal extension; however, two were intrathyroidal carcinomas and two were encapsulated carcinomas, larger than 5 cm in diameter. Distant metastases were confirmed morphologically in 18 patients (11 by surgical or biopsy material, five by autopsy, and two by cytology). The histologic types of metastatic tumors were consistent with those of primary thyroid tumors. Diagnostic 131I uptake was examined in 32 patients and absorption of diagnostic 131I in metastatic tumors was demonstrated in 21 patients. The 10-year survival rate of patients with 131I accumulating metastases (70%) was significantly better than that of patients with metastases lacking such uptake (40%). Immunoreactivity for thyroglobulin in metastatic tumors was correlated with the 131I absorption. This finding indicated that immunostaining of thyroglobulin in metastatic tumors might be useful in the prediction of the effectiveness of 131I therapy.     

Improvement of the fluorine-18 fluorodeoxyglucose images in simultaneous F-18 FDG/Tc-99m collimated spect imaging.

Collimated F-18 FDG SPECT imaging has been shown to be an acceptable alternative to F-18 FDG PET imaging for evaluating injured but viable myocardium. Ultra-energy (UHE) imaging is usually performed in simultaneous F-18 FDG/Tc-99m MIBI studies. The main limitations of this technique are degradation of the Tc-99m MIBI images due to F-18 downscatter to the Tc-99m window, and loss of resolution in Tc-99m images caused by using a UHE rather than a low-energy collimator. The quality of F-18 images has not been addressed. In our clinical and phantom studies we have found that F-18 images are inferior to simultaneously acquired Tc-99m MIBI images. This paper compares two correction methods for F-18 FDG images in a realistic cardiac phantom study. One approach is subtractive scatter correction, which employs a third 410 keV energy window image to estimate scatter. The other approach is based on restoration. The phantom acquisition was performed with 7.2 MBq of F-18 and 22.2 MBq of Tc-99m injected into the left ventricular (LV) wall. Three inserts, 3 cm, 2 cm, and 1 cm in diameter, were placed in the LV wall to simulate infarcts. Circumferential profiles were drawn from three successive short-axis slices and compared with true phantom data. The differences were calculated as root-mean-square error (rmse). Scatter correction improved rmse only 4.5 +/- 0.3%, while restoration improved rmse 16.1 +/- 0.4%, when compared with raw data. The same differences, measured as rmse, were 9.5 +/- 0.5, 6.8 +/- 0.4, and 5.1 +/- 0.5 for raw, scatter corrected, and restored F-18 data, respectively, when compared with Tc-99m window 140 keV data. The amount of noise, measured as root-mean-square % (rms%) was 5.3 +/- 0.5% for the Tc-99m image, 4.9 +/- 0.7% for the F-18 restored image, 6.2 +/- 0.6% for the raw F-18 image, and 6.5 +/- 0.9% for the scatter corrected F-18 image. The contrast measured for 2 cm and 3 cm inserts was 0.17 +/- 0.07 and 0.26 +/- 0.06 for F-18 raw data, 0.19 +/- 0.08 and 0.29 +/- 0.06 for the scatter corrected F-18 image, and 0.28 +/- 0.06 and 0.43 +/- 0.07 for the restored F-18 image. The contrast was 0.20 +/- 0.07 and 0.46 +/- 0.05 for the Tc-99m 140 keV window image. The restoration approach provided F-18 images of better contrast and detectibility than uncorrected or scatter corrected F-18 images. Restored F-18 images match better with the simultaneously acquired Tc-99m images.     

Predictive Factors of Malignancy in Thyroid Nodules with a Cytological Diagnosis of Follicular Neoplasm

In cases of follicular neoplasm identified by thyroid fine-needle aspiration (FNA), surgery is required to achieve a precise diagnosis. We investigated potential clinical factors for the preoperative prediction of malignancy in thyroid nodules with a cytological diagnosis of follicular neoplasm. We retrospectively reviewed the data of 97 patients who were diagnosed with follicular neoplasm by FNA and had undergone surgery at the Korea Cancer Center Hospital between April 2010 and April 2012. Age, sex, laboratory data (such as thyroid-stimulating hormone, free T4, thyroglobulin (Tg), and Tg antibody), and ultrasonographic findings were reviewed from the electronic medical records. Of 97 patients, 50 (51.5 %) were diagnosed with benign nodules, 16 (16.5 %) with follicular thyroid carcinoma (FTC), and 31 (32.0 %) with papillary thyroid carcinoma (PTC). In comparison with the features of benign nodules, FTC presented with a large nodule size, high serum Tg level, isoechogenicity, calcifications, and peripheral halo, whereas PTC exhibited traits similar to those of benign nodules, except for high serum Tg level and the presence of calcifications on ultrasonography. Therefore, a high serum Tg level (≥75 ng/mL) and calcification were the only significant predictive factors for malignancy in case of follicular neoplasm (p?<?0.01). Serum Tg levels and the presence of calcification on ultrasonography are important clinical features to predict malignancy in thyroid nodules with cytological diagnosis of follicular neoplasm.     

分化型甲状腺癌术后131I联合利可君治疗的临床应用研究

目的 探讨分化型甲状腺癌[differentiated thyroid carcinoma,DTC]术后131I联合利可君治疗的可行性,以提高甲状腺癌患者接受治疗期间的依从性和疗效.方法 回顾性分析2007年1月至2013年3月167例DTC术后残留、局部复发、淋巴结转移和/或全身转移的患者在接受131I治疗期间联合应用利可君治疗的效果.根据131I治疗前未给予利可君、131I治疗后给予利可君（20mg/次,tid）为A组47例;131I治疗前未给予利可君、131I治疗后给予利可君（40mg/次,tid）为B组57例;131I治疗前为预防WBC和PLT降低给予利可君（20mg/次,tid）、治疗后给予利可君（80mg/次,tid）为C组66例.结果 131I治疗和联合利可君治疗DTC患者167例,A、B、C三组患者在样本量、年龄相近、131I治疗前WBC、PLT水平的差异均无统计学意义（P＞0.05）;3组患者131I治疗后的WBC和PLT呈不同程度的变化,其中A组和B组的WBC和PLT可见明显减少（P＜0.05）,C组未见明显变化（P＞0.05）;131I治疗分化型甲状腺癌术后残留、局部复发或远处转移的疗效可靠.结论 分化型甲状腺癌术后131I治疗期间联合利可君治疗是预防WBC和PLT减少及骨髓抑制的有效方法.     

Evaluation of Incidental Thyroid Nodules in Cancer Patients

Objective

Frequency of thyroid cancer in incidental thyroid nodules identified by imaging techniques in cancer patients is higher than that in the normal population. In the retrospective study, we have both investigated the incidence of thyroid cancer in incidentally identified nodules and compared the imaging techniques to determine whether there is any difference between them in detection of malign nodules.

Clinical Utility of KAP-1 Expression in Thyroid Lesions

Although there are evidences of the involvement of KAP-1 in other tumors, data on differentiated thyroid carcinomas (DTC) are still lacking. We aimed to evaluate KAP-1 clinical utility in the diagnosis and prognosis of DTC. We used both visual immunohistochemistry and a semiquantitative analysis to evaluate KAP-1 expression in 230 thyroid carcinomas and 131 noncancerous thyroid nodules. There were 43 follicular carcinomas (FC) and 187 papillary thyroid carcinomas (PTC), including 130 classic (CPTC), 4 tall cells (TCPTC), and 53 follicular variants (FVPTC). Patients were followed up for 53.8?±?41 months. They were classified as free-of-disease (142 cases) or poor outcome (25 cases—10 deaths), according to their serum Tg levels and image evidences. KAP-1 was identified in 78 % PTC, 75 % TCPTC, 74 % FC, 72 % FVPTC, 55 % FA, 44 % hyperplasia, and 11 % normal thyroid tissues. A ROC analysis identified malignant nodules with 69 % sensitivity and 75 % specificity, using a cutoff of 73.19. In addition to distinguishing benign from malignant thyroid tissues (p?<?0.0001), KAP-1 expression differentiated CPTC from nodular hyperplasia (p?<?0.0001), CPTC from FA (p?=?0.0028), FVPTC from hyperplasia (p?=?0.0039), and FC from hyperplasia (p?=?0.0025). Furthermore, KAP-1 was more expressed in larger tumors (>4 cm; p?=?0.0038) and in individuals who presented recurrences/metastases (p?=?0.0130). We suggest that KAP-1 may help diagnose thyroid nodules, characterize follicular-patterned thyroid lesions, and identify individuals with poor prognosis.     

Expression of HBME-1 and CD56 in follicular variant of papillary carcinoma in children: An immunohistochemical study and their diagnostic utility

Papillary thyroid carcinoma (PTC) is the most common differentiated thyroid cancer in children; and the follicular variant is the second most common variant after the classic subtype. The histological appearance of follicular variant of papillary thyroid cancer (FVPTC), can be mimicked by benign follicular nodules. Pediatric pathologists encountering such lesions with FVPTC-like appearance may err on diagnosing the benign lesions as malignant. In adult patients, several immunohistochemical markers have emerged recently as a useful adjunct to distinguish differentiated thyroid carcinomas from benign follicular lesions. We undertook an inter-institutional retrospective study to establish the diagnostic utility of immunohistochemical staining for HBME-1, Galectin-3 and CD56 in differentiating FVPTC from its benign mimics, follicular adenoma and adenomatoid nodules, in children. Our specific aim of the project was to define the sensitivity and specificity of the three antibodies in FVPTC. Based on institutional diagnoses, a total of 66 cases were obtained: 32 FVPTC and 34 benign follicular nodules that comprised of 23 follicular adenoma and 11 adenomatoid nodules. Five investigators, who were blinded to the original diagnoses, independently reviewed the slides following pre-determined criteria and semi-quantitatively scoring the immunohistochemical staining. The immunohistochemical staining revealed that a combination of positive HBME-1 and negative CD56 result gave 100% specificity and positive predictive value in distinguishing FVPTC from benign follicular nodules. However, the antibody combination suffered from a lower sensitivity (50%). We used a cutoff of 25% positivity of tumor cells in determining positivity of tumor cells to an antibody. In conclusion, our study found a very high specificity and strong positive predictive value for the combination of HBME-1 and CD56 immunohistochemical stains in distinguishing FVPTC from benign follicular lesions.     

Efficacy of standard ten millicurie dose of radio-iodine in management of autonomously functioning toxic thyroid nodules

Therapeutic effect of radio-iodine treatment on thyroid patients with autonomously functioning toxic thyroid nodule was evaluated. Fifty one patients were given a standard dose of 10 mci of radioiodine (I-131) and were followed up for 2-3 years. The failure rate (relapse after 10 mci of radioiodine) of this regime was 10%. It was found that the nodules less than or equal to 3 cms. in size were completely cured after a dose of 10 mic. of radio-iodine therapy, over a follow up period of next 6 months. Patients having nodules larger than 3 cms. relapsed after first dose of 10 mci of radio-iodine, but were cured completely after the second dose of 10 mci of radio-iodine therapy. Tri-iodothyronine (T3) and thyroxine (T4) values were both found to be high before giving treatment in all the cases. Only one case developed hypothyroidism after radioiodine therapy.     

Encapsulated follicular variant of papillary thyroid carcinoma with bone metastases.

Although true follicular thyroid carcinoma is known to metastasize via the bloodstream and give rise to bone and lung metastases, such a pattern of spread is rare in papillary thyroid carcinoma. The follicular variant of papillary thyroid carcinoma (FVPTC) is believed to behave in a clinical manner similar to usual or classical papillary cancer and to follow a similar indolent course. There have been a few reports of "aggressive" FVPTC wherein follicular patterned tumors with nuclear features of papillary carcinoma have metastasized hematogenously; these neoplasms have been diffusely invasive or multicentric in the thyroid. We report five cases of FVPTC, which were encapsulated and simulated grossly and microscopically follicular adenomas. In two of these, the primary was discovered after clinical presentation of bone metastases. In three others, bony metastases (without other nonosseous metastases) arose 7 to 17 years after thyroid lobectomy for lesions initially diagnosed as follicular adenoma In retrospect, these three encapsulated lesions had vascular invasion. We wish to bring attention to these innocuous-appearing lesions, which, although sharing nuclear features of papillary cancer, behave clinically in an unexpectedly malignant fashion.     

Well-Differentiated Thyroid Cancer Neovasculature Expresses Prostate-Specific Membrane Antigen—a Possible Novel Therapeutic Target

Prostate-specific membrane antigen (PSMA), a type II transmembrane glycoprotein receptor, is highly expressed in prostate cancer and in the tumor neovasculature of colon, breast, and adrenocortical tumors. Here, we analyzed PSMA expression in the neovasculature of various thyroid cancer subtypes and assessed whether PSMA expression is correlated with aggressive behavior. From a prospectively maintained database, we evaluated 91 samples from 68 patients, including 37 primary differentiated thyroid cancers (DTCs) [11 classic papillary (cPTC), 9 follicular-variant (FvPTC), 11 follicular (FTC), 6 radioactive iodine-refractory (RAIR)], 5 anaplastic (ATC) carcinomas, 9 distant and 12 lymph node metastases, 21 benign thyroid nodules, and 7 normal thyroid specimens. Formalin-fixed paraffin-embedded tissue blocks were immunostained for vascular endothelial marker CD31 and PSMA with proper controls. PSMA expression was not detected in normal thyroid tissue. DTC tumors demonstrated a significantly higher PSMA expression, in regard to both intensity and percentage of vessels stained, than benign tumors (p < 0.001). Among the histologic subtypes, cPTC, FTC, and RAIR carcinomas demonstrated the highest percent of moderate to strong PSMA staining. PSMA expression was seen more frequently in specimens from distant metastases (100%) compared with specimens from only lymph node metastases (67%). PSMA is significantly overexpressed in the neovasculature of DTCs compared with normal and benign thyroid nodules specifically with increased expression in RAIR carcinomas and distant metastases. PSMA should be further explored as a novel therapeutic target for metastatic and RAIR carcinomas.     

131I治疗老年与非老年分化型甲状腺癌淋巴结转移的临床观察

目的探讨老年分化型甲状腺癌淋巴结转移（LMDTC）的临床影响因素及131I治疗效果与非老年LMDTC的差异。方法对38例LMDTC患者,用B超、CT、131I显像及Tg变化判断131I治疗效果差异。结果老年组与非老年组LMDTC比较：淋巴结大小（P=0.0452）及合并远处转移（P=0.0126）两组差异有统计学意义;131I治疗有效率老年组为64.7%（11/17）,非老年组为95.2%（20/21）,两组差异有统计学意义（P〈0.05）。随访期内未出现131I治疗引起造血系统抑制、慢性涎腺炎和继发肿瘤的发生。结论老年组与非老年LMDTC的临床影响因素有差异,131I治疗效果不及非老年组,但仍是有效且安全的治疗方法。     

Thyroid nodular lesion: analysis of cancer risk based on Kuma Hospital experience

It is a difficult question, whether it is malignant or not, when you follow up patients with thyroid nodular lesions. Cytological examination helps to solve this issue more accurately but a cancer risk still exists in patients with a negative cytology, non-diagnostic or suspicious follicular neoplasms. Analysis of cancer risk in patients with benign thyroid nodular lesions was carried out among 1044 cases who underwent thyroid surgery at Kuma Hospital, Kobe, Japan, in 2000. The purpose of this study was to provide evidence of cancer risk in those patients in Japan. Among the 356 cases with benign nodular lesions, 99 cases of papillary carcinoma were found in the thyroid parenchyma. Seventy-nine of the 99 cases were clinical cancer and were found preoperatively by cytology, while 20 out of 277 (7.22%) cases were found postoperatively as incidental carcinoma. The incidence of follicular carcinoma of a minimally invasive type in the index nodule was 22 out of 279 (7.89%) cases in patients who were surgically treated.     

Clinical significance of Tl-201/Tc-99m subtraction scintigraphy as a parameter for surgical indication of cold struma nodules

In a retrospective study Tl-201/Tc-99m subtraction scintigraphy (method acco. to Ferlin et al.) was performed in addition to Tc-99m scintigraphy, sonography and fine needle puncture in 400 patients. Postoperative histological evidence was available of all patients (carcinomas [n = 31], follicular and oncocytic adenomas [n = 235], nodular hyperplasia, Hashimoto's thyroiditis, Riedel's struma and de Quervain's thyroiditis [n = 134]). With regard to possible malignancy the sensitivity, in case of positive Tl-201 uptake was 85%. As however, adenomas also have a high tendency towards isolated Tl-201 uptake, the specificity for malignant growth was 62%. Thus Tl-201/Tc-99m subtraction scintigraphy is well suited as a criterion to exclude thyroid carcinomas; on the other hand, a positive Tl-201 uptake is not a fail-safe indication of malignant processes. At best it suggests the occurrence of autonomous growth and can thus, in addition to sonography and fine needle biopsy, serve as an aid in the decision as to whether surgical intervention is indicated.     

I-131-Lipiodol therapy in liver neoplasms

Twelve patients with liver neoplasms [10 HCC, 1 CCC, 1 multiple breast cancer metastases (BCM)] were treated by transarterial I-131-Lipiodol. Computed tomography (CT) and single photon emission CT (SPECT) showed pronounced I-131-Lipiodol accumulation in the tumor tissue in all cases. In three patients with HCC a reduction of tumor size was achieved after the first treatment. The remaining patients had big tumor masses; 5 of these (4 HCC, 1 CCC) had stable disease after the first treatment, and 2 HCC were progressive. One patient died immediately after therapy due to other reasons. The BCM proved significant reduction in number and size. Eighteen-FDG-PET (positron emission tomography with fluor-18-deoxy-glucose) and CT controls showed in part different results with pretherapeutic PET proving high interindividual variability in tumor activity. Side effects were tolerable. In summary, the therapy procedure with transarterial I-131-Lipiodol is safe and effective in tumors with moderate tumor mass.     

Differential Expression of a Set of Genes in Follicular and Classic Variants of Papillary Thyroid Carcinoma

Fine-needle aspiration biopsy (FNA) is currently the best initial diagnostic test for evaluation of a thyroid nodule. FNA cytology cannot discriminate between benign and malignant thyroid nodules in up to 30% of thyroid nodules. Therefore, an adjunct to FNA is needed to clarify these lesions as benign or malignant. Using differential display-polymerase chain reaction method, the gene expression differences between follicular and classic variants of papillary thyroid carcinoma (PTC) and benign thyroid nodules were evaluated in a group of 42 patients. Computational gene function analyses via Cytoscape, FuncBASE, and GeneMANIA led us to a functional network of 17 genes in which a core sub-network of five genes coexists. Although the exact mechanisms underlying in thyroid cancer biogenesis are not currently known, our data suggest that the pattern of transformation from healthy cells to cancer cells of PTC is different in follicular variant than in classic variant.