Publications by authors named "Chung-Yau Lo"

Cervical lymph node metastasis is frequent in patients with papillary thyroid carcinoma. In addition to the extent of thyroidectomy, the need as well as the extent of concomitant lymphadenectomy has been a subject of controversy and debate. The central compartment is the most frequent site of metastasis followed by the lateral compartment although skip metastasis in the lateral compartment can occur.

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Papillary thyroid carcinoma is the most common endocrine malignancy and accounts for the overwhelming majority of thyroid carcinoma. This recent dramatic increase in incidence is almost exclusively attributed to the incidental detection of small papillary thyroid carcinoma or microcarcinoma. Surgical management of thyroid carcinoma has been evolving to avoid overtreating patients by adopting the appropriate risk-based approach including the recommendation of hemithyroidectomy for low-risk carcinoma, the avoidance of routine prophylactic central nodal dissections, a higher threshold in using postoperative radioiodine ablation after total thyroidectomy, and the active observation or surveillance of papillary microcarcinoma as a viable alternative option instead of immediate surgical treatment.

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Vascular endothelial growth factor (VEGF) is important in pathogenesis of different cancers. The aim of this study is to investigate the relationships between different VEGFs and clinicopathological factors in patients with phaeochromocytomas. Twenty patients (10 men; 10 women) with non-hereditary, non-metastatic phaeochromocytomas were examined for VEGF mRNA expressions by polymerase chain reaction.

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Background: The aim of the study is to analyse the factors related to permanent surgical complications in children and adolescents with papillary thyroid carcinoma treated by total thyroidectomy with central and bilateral neck dissections.

Methods: Children and adolescents aged ≤18-year-old at presentation with papillary thyroid carcinoma during the years 1988-2010 underwent thyroid and lymph-node surgeries (with a median follow-up of 19.6 years) were analysed for post-surgical complications.

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Background: To balance the risk of disease progression, morbidity, and efficacy of reoperative central neck dissection (RCND) in papillary thyroid carcinoma, the latest clinical guidelines recommend early surgery over surveillance when the largest diseased node is >8 mm in its smallest dimension. However, the evidence remains scarce. To determine an appropriate size for first-time RCND, the relationship between size of largest diseased central node, morbidity, and response-to-therapy following RCND was examined.

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Background: Bilateral pheochromocytoma (PHEO) is more frequently found in patients with multiple endocrine neoplasia 2A carrying a RET germline mutation located in codon 634 (C634). However, it is unclear whether different amino acid substitutions within C634 cause differences in bilateral PHEOs expression. We aimed to answer this by pooling data from two Asian institutions.

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Background: Although an age cutoff of 45 years has often been adopted to stratify cancer risk in papillary thyroid carcinoma (PTC), both cancer-specific survival (CSS) and disease-specific survival (DFS) continue to worsen beyond this cutoff. This study aimed to determine whether advanced age (i.e.

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Background: Peri-operative hemodynamic instability (HDI) may increase peri-operative morbidity in pheochromocytoma/paraganglioma (PPGL) patients.

Objective: This study aimed to determine which tumor-related risk factors could lead to peri-operative HDI in unilateral or single PPGL removal.

Methods: Before surgery, 66 PPGL patients had at least two sets of 24 h urine collected for fractionated catecholamine analysis.

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Background: Although reoperative surgery in the central compartment (RCND) is indicated for bulky or progressive persistent/recurrent papillary thyroid carcinoma (PTC), its associated morbidity and disease outcomes remain unclear. We evaluated RCND outcomes by comparing them with those of patients who underwent primary central neck dissection (CND).

Methods: After matching for age, sex, tumor size, and initial tumor stage, the morbidity and outcomes of 50 consecutive patients who underwent RCND were compared with data from 75 patients who underwent primary therapeutic CND during the same period.

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Introduction: Transcutaneous laryngeal ultrasonography (TLUSG) is a promising alternative to direct laryngoscopy in assessing perioperative vocal cord function. This study sought to evaluate the accuracy of TLUSG in assessing vocal cord function.

Methods: Altogether, 204 patients underwent TLUSG and direct laryngoscopy before and after elective thyroidectomy.

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Vascular endothelial growth factor (VEGF) promotes growth of blood or lymphatic vessels. The aim of the current study is to identify relationships between VEGF-A and VEGF-C, and their impact in angiogenesis and metastases in thyroid cancers. VEGF-A and VEGF-C mRNA and protein expression was investigated in 136 thyroid cancers (123 papillary thyroid carcinomas and 13 undifferentiated thyroid carcinomas) and 40 matched lymph node metastases with papillary thyroid carcinoma using reverse transcription polymerase chain reaction and immunohistochemistry.

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Background: The issue of whether an involved but functioning recurrent laryngeal nerve (RLN) should be shaved or resected in locally advanced papillary thyroid carcinoma (PTC) remains controversial. Our study aimed to compare the early and late outcomes between those who underwent shaving and those who underwent resection and also to identify independent prognostic factors in this subset of patients.

Methods: Of the 77 patients with 1 RLN involved by PTC, 39 (50.

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Background: Because patients with differentiated thyroid carcinoma (DTC) presenting with distant metastasis (DM) have a particularly poor prognosis, examining the prognostic factors in this group is essential. We aimed to evaluate the prognostic factors affecting cancer-specific survival (CSS) in DTC patients presenting with DM.

Methods: Of the 1227 DTC patients, 51 (4.

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Background: Determinants for adequate lymph node yield (LNY) in prophylactic central neck dissection (pCND) for papillary thyroid carcinoma (PTC) remain unclear. We aimed to determine factors affecting LNY in pCND.

Methods: Of 230 patients, 109 (47.

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Background: Although postoperative hematoma after thyroidectomy is uncommon, patients traditionally have been advised to stay overnight in the hospital for monitoring. With the growing demand for outpatient thyroidectomy, we assessed its safety and feasibility by evaluating the potential risk factors and timing of postoperative hematoma after thyroidectomy.

Methods: From 1995-2011, 3,086 consecutive patients underwent thyroidectomy at our institution; of these, 22 (0.

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Background: The prognostic significance of size of central lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) remains unknown. Because postsurgical detectable stimulated thyroglobulin (DsTg) after radioiodine ablation may imply persistent or recurrent disease, we evaluated the association between size of CLNM and rate of DsTg in patients with PTC who underwent unilateral prophylactic central neck dissection.

Methods: To be eligible for analysis, the prophylactic central neck dissection specimen with <3 central lymph nodes (CLNs) or size of CLNM ≥1 cm as measured under the microscope was excluded.

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Background: Prognostic significance of metastatic central lymph node ratio (CLNR) in papillary thyroid carcinoma (PTC) remains unknown. Because postsurgical detectable stimulated thyroglobulin (DsTg) after radioiodine ablation may imply persistent or recurrent disease, we evaluated the association between CLNR and rate of DsTg in patients with PTC who underwent unilateral prophylactic central neck dissection.

Methods: To be eligible for analysis, the prophylactic central neck dissection specimen had to contain ≥3 central lymph nodes (CLNs) with ≥1 harboring metastasis.

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Background: Patients with eucalcemic parathyroid hormone elevation (ePTH) after parathyroidectomy for primary hyperparathyroidism (HPT) may be at risk of recurrence. We aimed to examine risk factors, trend of PTH level, and outcome of patients with ePTH 6 months after parathyroidectomy.

Methods: A total of 161 primary HPT were analyzed.

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Background: Although thyroidectomy for Graves' disease (GD) is well established, surgical indications remain less well defined. This study aimed to evaluate the changes in surgical indication, type of resection, and surgical outcomes at a single institution.

Methods: A total of 346 patients who underwent thyroidectomy for GD were divided into 2 time periods: period 1 (1995-2001) and period 2 (2002-2008).

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Background: Prophylactic central neck dissection (CND) remains controversial in papillary thyroid carcinoma (PTC). Because postsurgical stimulated thyroglobulin (sTg) level is a good surrogate for recurrence, the study aimed to evaluate the impact of prophylactic CND on preablative and postablative sTg levels after total thyroidectomy.

Methods: Of the 185 patients retrospectively analyzed, 82 (44.

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Aims: There are no quantitative data on the mRNA expression of epidermal growth factor receptor (EGFR) and transformation growth factor alpha (TGF-α) in thyroid carcinoma. The aims of this study were to detect, quantify and analyse the clinicopathological correlations of the expression of these genes in a large cohort of patients with thyroid carcinoma.

Methods: EGFR and TGF-α expression were investigated using real time quantitative polymerase chain reaction and immunohistochemistry on 71 papillary thyroid carcinomas (PTCs), 68 paired non-cancer thyroid tissues adjacent to the PTC and 20 benign thyroid lesions.

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Background: There are few data on the degree to which thyroid cancer survivors are at risk of second primary malignancy (SPM). This study aimed at evaluating the risk of SPM in patients with differentiated thyroid carcinoma (DTC) and how the timing of SPM might affect the disease course.

Methods: Among 1,043 patients diagnosed with DTC between 1970 and 2008, 27 (2.

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Over the last decade, surgeons have witnessed dramatic changes in surgical practice as a result of the introduction of new technological advancement. Some of these changes include refinement of techniques in thyroid cancer surgery. The development of various endoscopic thyroidectomy techniques, the addition of the da Vinci robot, and the use of operative adjuncts in thyroid surgery, such as intraoperative neuromonitoring and quick intraoperative parathyroid hormone, have made thyroid cancer surgery not only safer and better accepted by patients with thyroid cancer but also offer them more surgical treatment options.

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Background: Concurrent vitamin D(3) deficiency is common in primary hyperparathyroidism (pHPT). We aimed to examine the clinicopathologic features and short-term outcomes of vitamin D(3)-deficient patients after minimally invasive parathyroidectomy (MIP).

Methods: Over 2-year period, 80 consecutive MIP patients had preoperative-fasting 25-hydroxyvitamin D(3) (25OHD(3)) checked.

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