Szu-Tah Chen

Analysis of sonographic features for the differentiation of benign and malignant breast tumors of different sizes.

To analyze the value of various sonographic features in differentiating benign from malignant breast tumors of different sizes to improve the diagnostic accuracy in small lesions.

C-reactive protein as an outcome predictor for percutaneous transluminal angioplasty in diabetic patients with peripheral arterial disease and infected foot ulcers

AIM Although percutaneous transluminal angioplasty (PTA) is an effective therapeutic procedure for critical limb ischemia, several clinical factors can influence the outcome of PTA for peripheral arterial disease (PAD). The aim of this study is to identify the outcome predictors of PTA in infected diabetic foot patients with PAD. METHODS Eighty-five diabetic patients with a total of 90 infected limbs treated by PTA participated in this study. Patients were initially admitted for infected foot ulcers and were later diagnosed with PAD. Even though all patients underwent successful PTA within 15 days of admission, limb salvage was successful in 66 cases while 24 underwent subsequent amputation. The clinical characteristics and laboratory variables of both groups before PTA were compared and analyzed. RESULTS Significantly higher level of C-reactive protein (CRP) was observed in the major amputation group before PTA. The cutoff value via receiver operating characteristic curve was 50mg/L (81.8% specificity, 70.7% sensitivity). Multivariate logistic regression analysis revealed that CRP levels may serve as valuable marker in determining a successful outcome. CONCLUSION Reduced CRP levels (<50mg/L), which indicates a low infection severity, may serve as a major predictor of successful PTA outcome in diabetic patients with infected foot ulcers.

Comparison of membrane proteins from benign and malignant human thyroid tissues by two-dimensional polyacrylamide gel electrophoresis

In this study two-dimensional (2D) polyacrylamide gel electrophoresis with silver staining was used to analyze cellular membranous proteins of various normal and pathological human thyroid tissues. The aim was to understand the differences in cellular membranous proteins between these tissues, which would aid in the differential diagnosis of thyroid malignancy. Characteristic protein spots had a molecular mass of 50-64 kDa and a pI of 5.7-6.5. There were two groups of isoform protein spots in this area. The higher-molecular-mass group was found in follicular thyroid cancer tissues which and was not visible in normal thyroid tissues. The low-molecular-mass group was found in follicular carcinoma or adenoma tissues and was detected in one to three spots. The papillary thyroid carcinoma tissues gave different 2D gel maps. There were few spots of papillary thyroid carcinoma tissue membranous proteins within the examined area. The 2D gel maps may be used for differential diagnosis of follicular neoplasm. The characteristics of these protein spots require further investigation.

Disease-specific mortality and secondary primary cancer in well-differentiated thyroid cancer with type 2 diabetes mellitus.

Background Increased body mass index is related to the incidence of thyroid cancer. However, the presentation and therapeutic outcomes of different thyroid cancers and type 2 diabetes mellitus (DM) have not been studied. This study investigated the effect of type 2 DM on the clinical presentations and therapeutic outcome of well-differentiated thyroid cancer. Methods and Findings A retrospective analysis of adult thyroid cancer patients with or without type 2 DM admitted between January 2001 and December 2010 was performed at an institution. A total of 1,687 well-differentiated thyroid cancer patients with different histological patterns were enrolled. Among these subjects, 122 were type 2 DM patients. Patients with thyroid cancer and type 2 DM were significantly older than non-DM patients. After a mean follow-up period of 5.6±0.1 years, patients with thyroid cancer and type 2 DM showed a higher percentage of disease progression than non-DM patients (24.6% vs. 17.4%). In addition, disease-specific mortality was higher in the type 2 DM group (10.7% vs. 3.8%). Thyroid cancer patients with type 2 DM showed a higher percentage of secondary primary cancers than those without DM (10.7% vs. 4.9%). Thyroid cancer-specific survival rates in the type 2 DM and non-DM groups were 82.2% and 94.9% at 5 years, 72.9% and 91.4% at 10 years, and 36.5% and 61.3% at 20 years, respectively. Multivariate analysis showed that type 2 DM was independent of thyroid cancer-specific mortality. Conclusion Patients with type 2 DM and well-differentiated thyroid cancer had an advanced tumor-node-metastasis stage at the time of diagnosis and an increased disease-specific mortality. Aggressive surgical procedures and close follow-up for well-differentiated thyroid cancer patients with type 2 DM are therefore necessary.

Gender-Specific Variation in the Prognosis of Papillary Thyroid Cancer TNM Stages II to IV

To investigate the correlation between gender and the clinical presentation of papillary thyroid cancer and the long-term followup results, 435 patients who underwent total or near-total thyroidectomy were enrolled in this study. Among these papillary thyroid cancer patients, 12.2% showed lymph node metastases and a higher incidence of male patients in the N1b group. There were 65 from 316 female (20.6%) and 49 from 120 male (40.8%) patients who had a postoperative disease progression. A total of 55 (12.6%) patients died of thyroid cancer. Male patients showed a higher thyroid cancer mortality than the females. Multiple regression analysis showed that male gender was an independent risk factor for cancer recurrence and mortality. Male patients with TNM stages II to IV of papillary thyroid cancer need to adopt aggressive surgical and postoperative 131I therapy.

Risk factors of distant metastasis in the follicular variant of papillary thyroid carcinoma.

BACKGROUND/PURPOSE The follicular variant of papillary thyroid carcinoma (FVPTC) is the most common variant of papillary thyroid carcinoma (PTC). A previous population-based study revealed its clinical behavior as a mix of classic papillary thyroid carcinoma (C-PTC) and follicular thyroid carcinoma. Whereas locoregional extension was lower in FVPTC than in C-PTC, the distant metastasis rate was higher in FVPTC than in C-PTC. The aim of this study was to evaluate the risk factors of distant metastasis in FVPTC postoperatively. METHODS A retrospective review of 359 patients with final pathological diagnosis of FVPTC treated at Chang Gung Memorial Hospital between January 2000 and January 2014 was performed. After excluding patients who had inadequate pathological data for analysis or did not attend regular follow up for >1 year, 346 patients were included in this study. Univariate and multivariate statistical analyses were performed to determine the significance of various factors. RESULTS Of the 346 patients with FVPTC, 19 (5.5%) had lymph node metastases and 32 (9.2%) had distant metastases. Two positive and one negative risk factors were predictive for distant metastasis using multivariate analysis: angiolymphatic invasion [odds ratio (OR), 3.085; 95% confidence interval (CI), 1.008-9.442], extrathyroidal extension (OR, 3.929; 95% CI, 1.330-11.602), and encapsulation (OR, 0.361; 95% CI, 0.154-0.850). CONCLUSION The presence of angiolymphatic invasion, extrathyroidal extension, or nonencapsulation was associated with distant metastasis in FVPTC in this study. In FVPTC patients, postoperative investigation for distant metastasis may be warranted by the presence of these two positive risk factors or the absence of the one negative risk factor.

Long-term follow-up of papillary and follicular thyroid carcinomas with bone metastasis

The aims of this study were to investigate papillary and follicular thyroid carcinomas with bone metastasis in various clinical presentations and to determine the prognostic factors after multimodality treatment. A retrospective analysis was performed of 3,120 patients with papillary and follicular thyroid carcinoma. Of these patients, 131 (including 97 women, 71.8%) were diagnosed with bone metastasis and underwent follow-up at the Chang Gung Medical Center. Patients with bone metastasis were categorized into two groups. Group A was comprised of patients who were diagnosed with bone metastasis either before thyroidectomy or within 6 months of the initial thyroidectomy (90 patients, 68.7%). Group B was comprised of patients with bone metastasis who received a diagnosis 6 months post-thyroidectomy in the follow-up period (41 patients, 31.3%). After a mean follow-up period of 8.4 ± 7.0 years, there were 88 deaths (67.2%) attributed to thyroid cancer and 13 patients (9.9%) achieved disease-free status. A multivariate analysis showed that older age, early diagnosis, and brain metastasis were each associated with a poor prognosis. The difference in disease-specific mortality rates between groups A and B was significant (p < 0.0001). In conclusion, papillary and follicular thyroid cancers with bone metastasis have a high rate of mortality. Despite this high mortality, 9.9% patients still had an excellent response to treatment.

Therapeutic Outcomes of Patients with Multifocal Papillary Thyroid Microcarcinomas and Larger Tumors

A retrospective review of 626 patients with multifocal papillary thyroid carcinoma (PTC) including 147 patients (23.5%) with multifocal papillary thyroid microcarcinoma (PTMC) from a total of 2,536 patients with PTC who visited the Chang Gung Medical Center in Linkou, Taiwan, was performed. A comparison of the clinical features between 626 multifocal and 1,910 solitary PTC cases showed that patients in the multifocal PTC group were older and had a smaller mean tumor size, a more advanced tumor-node-metastasis (TNM) stage, and a higher percentage of nonremission status compared to patients in the solitary PTC group. Of the 626 patients with multifocal PTC, the group with larger tumors showed a more advanced TNM stage, a higher percentage of lymph node metastasis and soft tissue invasion, and a higher nonremission rate compared to the multifocal PTMC group. Of the 626 patients with multifocal PTC, 25 patients (4%) died during a mean follow-up period of 7.1 ± 5.3 years. Kaplan-Meier survival curves showed a significantly lower survival rate associated with multifocal PTMC compared to that with solitary PTMC.

Synergistic Effect of Hyperglycemia and p27(kip1) Suppression on Adult Mouse Islet Beta Cell Replication.

The complementary role of hyperglycemia and p27kip1 suppression on islet beta cell regeneration was investigated in a syngeneic mouse model. p27kip1 gene silencing was performed by infecting islets of C57BL/6 with shRNA lentiviral particles. At 54 hours after viral infection, p27kip1 protein content in cultured targeting islets was 22% of that in freshly isolated islets. Six days after transplantation to diabetic mice, targeting islet graft had considerably more cells with Ki67-staining nuclei than nontargeting islets. The mice in the targeting-islet group had a significantly shorter duration of temporary hyperglycaemia than mice in the non-targeting-islet group. The long-term ex vivo beneficial effect of p27kip1 silencing on graft function was also indicated by the significantly higher cumulative cure rate for diabetes in mice receiving 200 targeting islets than that in mice receiving 200 non-targeting islets. Our data suggest that hyperglycemia and persistent p27kip1 suppression have a synergistic effect on islet beta cell replication in adult mice.

Down-regulation of matrix metalloproteinase-7 inhibits metastasis of human anaplastic thyroid cancer cell line

Epigenetic drugs such as histone deacetylase inhibitors (HDACIs) possess anticancer properties due to its ability to regulate genes associated with tumor growth, differentiation, apoptosis and metastasis. In addition to its apoptotic effect, phenylbutyrate (PB), a carboxylic acid HDACI, inhibited an anaplastic (ATC) thyroid cancer cell line ARO from penetrating a matrigel coated transwell with concomitant suppression of a metastasis-associated gene, matrix metalloproteinase-7 (MMP-7) and stimulation of a transformation suppressor protein, reversion-inducing- cysteine-rich protein with Kazal motifs without affecting MMP-2 expression levels. Direct evidence suggesting MMP-7 down-regulated cancer metastasis came from the observation of a decreased pulmonary metastasis in SCID mice xeno-transplanted with MMP-7-knocked-down ARO cells. In addition, H-89, a protein kinase A inhibitor, remarkably restored the down-regulaed MMP-7 level treated by PB. Thus, the suppressive effect of PB on MMP-7 was partially carried out through H3 phosphoacetylation. To conclude, our findings suggest PB inhibits MMP-7 expression epigenetically through phosphoacetylation of histone proteins, and thereby, reduced invasive ability of an ATC thyroid cancer cell line.