Lactate Dehydrogenase A as a Potential New Biomarker for Thyroid Cancer.

BACKGROUND: Several cancers show increased levels of lactate dehydrogenase A (LDHA), which are associated with cancer progression. However, it remains unclear whether LDHA levels are associated with papillary thyroid cancer (PTC) aggressiveness or with the presence of the PTC prognostic marker, the BRAFV600E mutation. This study aimed to evaluate the potential of LDHA as a PTC prognostic marker. METHODS: LDHA expression was examined in 83 PTC tissue specimens by immunohistochemistry. Human thyroid cell lines were genetically manipulated to overexpress BRAFV600E or were treated with a BRAF-specific short hairpin RNA (shBRAF), whose effects on LDHA expression were evaluated by Western blotting. Data from 465 PTC patients were obtained from The Cancer Genome Atlas (TCGA) database and analyzed to validate the in vitro results. RESULTS: LDHA was aberrantly overexpressed in PTC. Intense immunostaining for LDHA was observed in PTC specimens carrying mutated BRAF, whereas the intensity was less in wild-type BRAF samples. Overexpression of BRAFV600E resulted in LDHA upregulation, whereas treatment with shBRAF downregulated LDHA in human thyroid cell lines. Furthermore, LDHA mRNA expression was significantly elevated and associated with BRAFV600E expression in thyroid cancer tissues from TCGA database. Additionally, LDHA overexpression was found to be correlated with aggressive clinical features of PTC, such as lymph node metastases and advanced tumor stages. CONCLUSION: LDHA overexpression is associated with the BRAFV600E mutation and an aggressive PTC behavior. Therefore, LDHA may serve as a biomarker and therapeutic target in PTC.

Hemodynamic stability during adrenalectomy for pheochromocytoma: A case control study of posterior retroperitoneal vs lateral transperitoneal approaches.

Hemodynamic stability is one of the most critical aspects of adrenal surgery for pheochromocytoma. Few articles have evaluated the hemodynamic status of patients undergoing posterior retroperitoneal adrenalectomy (PRA) for pheochromocytoma. The aim of this study is to compare the intraoperative hemodynamic parameters between lateral transperitoneal adrenalectomy (TPA) and PRA in this groups of patients.This report describes a retrospective study of 53 pheochromocytoma patients who underwent endoscopic adrenalectomy via transperitoneal (22 patients) or posterior retroperitoneal (31 patients) approaches from January 2008 to March 2015. Data from these patients were compared to investigate the differences in hemodynamic parameters between the 2 approaches.Clinical parameters at presentation were similar between the 2 groups, except for tumor size, which was larger in the TPA group. The PRA group is associated with reduced operative time, blood loss, and length of hospital stay compared to TPA even after adjusting for the tumor size. There was greater BP fluctuations and higher maximum systolic and diastolic blood pressure (BP) within the TPA group compared to PRA during univariate analysis. This was however not significant after adjusting for tumor size. There was no difference in the intraoperative inotropic support requirement between the 2 groups.PRA is associated with stable intraoperative hemodynamic status, as well as favorable perioperative outcomes compared to TPA in patients with small pheochromocytomas.

Oncologic outcomes in patients with 1-cm to 4-cm differentiated thyroid carcinoma according to extent of thyroidectomy.

BACKGROUND: Recent guidelines advocate unilateral thyroidectomy for low-risk 1-cm to 4-cm differentiated thyroid cancer (DTC). This study was designed to examine the association between the extent of thyroidectomy and oncologic outcomes in patients with 1-cm to 4-cm DTC. MATERIALS AND METHODS: From April 1978 to December 2011, 16 057 patients with DTC underwent thyroidectomy at Yonsei University Hospital. Among them, 5266 (32.8%) patients were classified as having 1-cm to 4-cm DTC and were enrolled in this study. Clinicopathologic features and prognostic results (disease-free survival [DFS] and disease-specific survival [DSS] rates) were analyzed by retrospective medical record review. The mean follow-up duration was 57.3 ± 58.1 months. RESULTS: Of tumor subtypes in the study group, papillary thyroid carcinoma was the most common (97.5%) and follicular thyroid carcinoma occurred at a rate of 2.5%. In this study, the mean tumor size was 1.84 ± 0.74 cm. Patients had extrathyroidal extension (69.3%), multiplicity (35.1%), bilaterality (26.4%), central lymph node metastasis (53.0%), and lateral neck node metastases (19.9%). Of the 5266 patients, 4292 (81.5%) underwent total thyroidectomy and 974 (18.5%) had lobectomies. Recurrence rates in the total thyroidectomy and lobectomy groups were 5.7% and 9.4%, respectively. The lobectomy group had lower DFS (P = .007) and higher DSS (P = .034) than the total thyroidectomy group. A multivariate analysis for DFS revealed that tumor size, N classification, and extent of thyroidectomy were independent risk factors. On multivariate analysis, independent risk factors for DSS were age, sex, tumor size, and M classifications. CONCLUSION: Although extent of thyroidectomy does not affect DSS, total thyroidectomy is beneficial for reducing recurrence in patients with 1-cm to 4-cm DTC. However, if such tumors have such low-risk features as being unifocal, intrathyroidal, and lymph node metastasis-negative, extent of thyroidectomy does not affect oncologic outcome and lobectomy may be sufficient.

Dynamic risk stratification in medullary thyroid carcinoma: Single institution experiences.

Recently, dynamic risk stratification has been found to be more valuable than static anatomic staging system in nonmedullary thyroid cancer and this strategy has also been accepted in medullary thyroid cancer (MTC). The present study was designed to compare the clinical usefulness of response to initial therapy stratification with a traditional anatomic staging system.From August 1982 to December 2012, a total of 144 MTC patients underwent thyroidectomy in Yonsei University Hospital. Among them, 117 (82.2%) patients with complete clinical data and sustained follow-up were enrolled in this study. Clinicopathological features and surgical outcomes were analyzed by retrospective medical chart review. Mean follow-up duration was 85.78 ±â€Š62.51 months.In this study, mean tumor size was 1.94 ±â€Š1.40 cm and 22 (18.9%) patients had hereditary MTC; 95 (81.1%) patients had sporadic MTC. Stage I patients had highest probability of excellent response to initial therapy (92.1%). Stage IV patients had highest probability of biochemical and structural incomplete response to initial therapy (57.5% and 30.3%) and lowest probability of excellent response to initial therapy (12.1%). Both response to initial therapy stratification and TNM staging system offered useful prognostic information in this study. The TNM staging system provided risk stratification pertaining to disease-free survival (DFS), disease-specific survival (DSS), and the probability of having no evidence of disease at final outcome, but did not provide risk stratification pertaining to the probability of having biochemical persistent/recurrence disease at final outcome. However, response to initial therapy stratification provided risk stratification pertaining to not only DFS, DSS, and the probability of having no evidence of disease at final outcome but also the probability of having biochemical persistent/recurrence disease at final outcome.In this study, we demonstrated that dynamic risk stratification with adjusted response to initial therapy system can offer more useful prognostic information than anatomic staging system in MTC.

Transaxillary robotic modified radical neck dissection: a 5-year assessment of operative and oncologic outcomes.

BACKGROUND: Robotic modified radical neck dissection (MRND) using a gasless transaxillary approach has been reported to be a safe and meticulous technique in patients with papillary thyroid carcinoma (PTC) and lateral neck node metastasis (N1b). Few studies, however, have attempted to assess the long-term oncologic outcomes of robotic MRND in these patients. This study aimed to compare perioperative and 5-year oncologic outcomes of robotic MRND with conventional open procedures in patients with N1b PTC. METHODS: Between September 2007 and February 2010, 193 patients with N1b PTC underwent total thyroidectomy and MRND by a single surgeon. Of these, 42 (21.8 %) underwent robotic procedures and 151 (78.2 %) underwent conventional open procedures. All patients received 3.7- to 5.5-GBq radioactive iodine (RAI) ablation, post-therapy whole-body scans (TxWBSs), and diagnostic WBS (DxWBSs) during follow-up. An exact 1:3 matching for age and stage was performed to minimize selection bias, and perioperative and 5-year oncologic outcomes were compared in the matched groups. RESULTS: The mean follow-up period was 66.0 months (range 60-90 months). Number of retrieved cervical lymph nodes (LNs) (p = .102) and postoperative ablation success rates (p = .864) were similar between the two groups. TSH-suppressed serum Tg concentrations after 5 years (0.7 ± 1.5 vs. 2.4 ± 14.1 ng/ml; p = .471) and recurrence rates in the robotic and open groups (1/41 [2.4 %] vs. 3/102 [2.9 %]; p = .864) were similar for the 5-year follow-up period. Four patients experienced recurrence: Three exhibited regional lymph node metastasis, and one showed bilateral lung metastases. CONCLUSION: The perioperative and 5-year oncologic outcomes were similar after robotic and conventional open MRND. Large, prospective randomized controlled trials with long-term follow-up data are needed to validate these results.

Is focused parathyroidectomy appropriate for patients with primary hyperparathyroidism?

PURPOSE: The aim of this study was to determine whether focused or complete parathyroidectomy was more appropriate and to compare follow-up data in primary hyperparathyroidism (PHPT). METHODS: We retrospectively analyzed 225 operations for PHPT at Yonsei University Health System between 2000 and 2012. After excluding 93 patients, the remaining 132 were divided into 2 groups: those who underwent focused parathyroidectomy (FP) and those who underwent conventional parathyroidectomy (CP). We compared clinicopathological features; preoperative calcium, parathyroid hormone (PTH), phosphorus, vitamin D, 24-hour urine calcium, and alkaline phosphatase levels; postoperative calcium and PTH levels; pathologic diagnosis; multiplicity; and results of a localization study between the 2 groups. RESULTS: There was no significant difference in the rates of development of postoperative persistent hyperparathyroidism (1/122 FP patients and 1/10 CP patients) between the 2 groups due to a technical reason (FP 0.8% vs. CP 10.0%, P = 0.146). Multiglandular disease (MGD) was uncommon in all cases (6 of 132, 4.5%). All MGD cases were diagnosed using a preoperative localization study. Sestamibi scan and ultrasonography sensitivity were 94.2% and 90.2%, respectively. CONCLUSION: We suggest that FP is appropriate in PHPT, except in cases of MGD if detected before the operation using preoperative imaging. Knowledge of hereditary PHPT and improved preoperative localization studies, such as high-resolution ultrasonography, contributed to the decision to perform FP rather than CP in all cases of unilateral results of the localizing study.

Optimal Cut-Off Values of Lymph Node Ratio Predicting Recurrence in Papillary Thyroid Cancer.

Regional lymph node (LN) metastasis has a significant impact for prediction of recurrence in patients with papillary thyroid cancers (PTC); however, the prognostic value of the lymph node ratio (LNR), which is defined as the ratio of the number of metastatic LNs to the total number of investigated LNs, is controversial. In this study, we determined the optimal cut-off values of LNRs for the prediction of recurrence in PTC patients.This large cohort study retrospectively evaluated 2294 patients who had undergone total thyroidectomy for PTC at a single institution from October 1985 to June 2009. The prediction probability of central LNR (cLNR, level VI) and total LNR (tLNR, levels II-VI) were estimated by binominal logistic regression analysis. Hazard ratios of the cut-off LNR values for cancer recurrence were calculated for relevant covariates using multivariate Cox regression analyses. Kaplan-Meier analyses were also utilized to assess the effects of estimated LNR cut-off values on recurrence-free survival (RFS).Of the 2294 patients, 138 (6.0%) presented cancer recurrence during the follow-up period (median duration = 107.1 months). The prediction probability indicated that LNRs of 0.4 and 0.5 for central LN and total LN, respectively, are optimal cut-off values for precise prediction with minimization of outliers. Multivariate Cox regression analyses revealed that cLNR ≥0.4 was independently predictive of recurrence in patients with N0 and N1a PTCs (hazard ratio [HR]: 7.016, 95% confidence interval [CI]: 3.72-12.986, P < 0.001) and that tLNR ≥0.5 indicated a significantly increased risk of recurrence in patients with N1b PTCs (HR: 2.372, 95% CI: 1.458-3.860, P < 0.001). In addition, Kaplan-Meier analyses clearly demonstrated that these LNR cut-off values are precisely operational in RFS estimation.The cut-off LNR values of 0.4 and 0.5 for cLNR and tLNR, respectively, were identified. Risk stratification combined with these LNR cut-off values may prove useful to determine treatment and follow-up strategies for PTC patients.

Long-term oncologic outcome of robotic versus open total thyroidectomy in PTC: a case-matched retrospective study.

PURPOSE: The role of the robot in thyroid surgery remains uncertain, and it is unclear whether robotic total thyroidectomy (R-TT) can be justified as a standard treatment for patients with thyroid cancer. This study compared the long-term operative results and oncologic outcomes of R-TT and conventional open TT (O-TT) after propensity score matching of the cohorts. METHODS: This study retrospectively evaluated patients with papillary thyroid cancer (PTC) who underwent TT with central compartment node dissection (CCND) by a single surgeon in tertiary medical center. Of the 833 patients, 94 (11.3 %) were lost to follow-up. 245 (33.2 %) underwent R-TT, and 494 (66.8 %) underwent O-TT. The mean follow-up duration was 74 (range 61-91) months. Propensity score matching in age, gender, tumor size, extrathyroidal invasion, multiplicity, bilaterality, and TNM stage identified 206 pairs of patients. The long-term oncologic outcomes were assessed in the R-TT and O-TT groups before and after adjustment for baseline covariates. RESULTS: After adjustment for baseline covariates, serum thyroglobulin (Tg) (p = 0.746) and anti-thyroglobulin antibody (TgAb) (p = 0.394) concentrations were similar in the two groups 5 years after surgery. Nine patients experienced locoregional recurrence, six in the O-TT and three in the R-TT group, with all recurrences in regional LNs. Disease-free survival (DFS) was similar in the R-TT and O-TT groups before matching (p = 0.890) and after adjustment for baseline covariates (p = 0.882). CONCLUSION: This represents the first report of 5-year surgical outcomes in patients who underwent R-TT for thyroid cancer. Long-term oncologic quality was similar after R-TT and O-TT.

Is Preoperative Vitamin D Deficiency a Risk Factor for Postoperative Symptomatic Hypocalcemia in Thyroid Cancer Patients Undergoing Total Thyroidectomy Plus Central Compartment Neck Dissection?

BACKGROUND: Although some studies have reported that preoperative vitamin D deficiency (VDD) is a risk factor for hypocalcemia after total thyroidectomy (TT) in patients with nontoxic multinodular goiter or Graves' disease, the association between VDD and postoperative hypocalcemia in thyroid cancer patients undergoing TT plus central compartment neck dissection (CCND) remains unclear. This study evaluated whether preoperative VDD was associated with postoperative symptomatic hypocalcemia. MATERIALS AND METHODS: Data were collected prospectively between September 2012 and May 2013. A total of 267 consecutive thyroid cancer patients who underwent TT with CCND were analyzed. Patients were divided into two groups--VDD or non-VDD--by preoperative vitamin D level of <10 or ≥10 ng/mL. Symptomatic hypocalcemia was defined as serum calcium <8.2 mg/dL and symptoms or signs of hypocalcemia. The rates of postoperative symptomatic hypocalcemia and clinicopathological features were compared between the two patient groups. RESULTS: The rate of postoperative symptomatic hypocalcemia was higher in the VDD group than in the non-VDD group (43.8% vs. 30.4%, p=0.043). By logistic regression analysis, predictive factors for postoperative symptomatic hypocalcemia included a preoperative vitamin D level of <10 ng/mL (p=0.007; odds ratio=3.00). In patients who had postoperative intact parathyroid hormone (iPTH) levels <15 pg/mL, symptomatic hypocalcemia was more common in the VDD group than in the non-VDD group (77.5% vs. 53.2%, p=0.008). The findings show that a preoperative vitamin D threshold level of >20 ng/mL reduced the risk of symptomatic hypocalcemia by 72% when compared with patients with VDD (p=0.003). CONCLUSION: VDD is significantly associated with postoperative symptomatic hypocalcemia in thyroid cancer patients undergoing TT plus CCND. VDD was predictive for symptomatic hypocalcemia when patients had postoperative serum iPTH levels <15 pg/mL. Thus, preoperative supplementation with oral vitamin D should be considered to minimize postoperative symptomatic hypocalcemia.

Sirt1 induction confers resistance to etoposide-induced genotoxic apoptosis in thyroid cancers.

Despite the favorable therapeutic outcomes reported in differentiated thyroid cancer (DTC), a significant proportion of DTC patients present with refractory behavior to conventional therapy. The sirtuin (Sirt) family has recently been implicated in the maintenance of cellular homeostasis under genotoxic stress. Here, we investigated the induction of Sirt1 expression by etoposide-induced genotoxic stress to gain insights into thyroid carcinogenesis and identify novel therapeutic targets. Immunohistochemical staining analyses of Sirt1 and Sirt3 were performed using human thyroid cancer tissues and matched normal tissues, and bioinformatic analyses were done using public repositories, including the Human Protein Atlas, BioGPS, NCBI Gene Expression Omnibus (GEO) profiles, and GeneNetwork. TPC1, FTC133 and FRO cells were used for molecular biological experiments including apoptosis assays, MTT, immunofluorescence staining and qRT-PCR assays. The IHC data and public repositories data consistently showed variable Sirt1 and Sirt3 expression patterns in normal thyroid follicular cells and papillary thyroid cancer cells. The induction of Sirt1 and Sirt3 was cell type-specific and the expression levels of these genes correlated with apoptotic cell death and cell viability after etoposide-induced genotoxic stress. Sirt1­Foxp3 signaling-mediated regulation of Bax and p21 mRNA expression was a signature molecular event in TPC1 cells, which showed remarkable resistance to etoposide-induced genotoxic stress. The induction of Sirt1 and Sirt3 may be a determinant of thyroid cancer cell survival under genotoxic stress conditions. Further examination of the Sirt1-Foxp3 signal may improve our understanding of thyroid carcinogenesis and help identify new druggable targets.

Surgical complications after robotic thyroidectomy for thyroid carcinoma: a single center experience with 3,000 patients.

BACKGROUND: Robotic thyroidectomy (RT), a new gasless, transaxillary approach developed by the Yonsei University group in Seoul, Korea, eliminates the need for a cervical incision. Since RT is technically complex and has a steep learning curve, the surgical complication rate may initially be higher than with conventional surgery. This study evaluated the complication rates of transaxillary RT and assessed ways to prevent surgical complications. METHODS: Between October 2007 and March 2013, 3,000 patients underwent RT for thyroid cancer in the Department of Surgery, Yonsei University College of Medicine at Severance Hospital, Seoul. The medical records of these patients were reviewed retrospectively, and surgical complications were assessed on the basis of clinical findings. RESULTS: The most common surgical complication was symptomatic hypocalcemia, of which 37.43 % cases were transient and 1.10 % permanent. Other surgical complications included recurrent laryngeal nerve injury (1.23 % transient, 0.27 % permanent), seroma (1.73 %), hematoma (0.37 %), chyle leakage (0.37 %), trachea injury (0.2 %), Horner's syndrome (0.03 %), carotid artery injury (0.03 %), and brachiocephalic vein injury (0.03 %). The technique-related complications, which were never seen in conventional open thyroidectomy, were axillary skin flap perforation (0.1 %), and traction injury of the arm on the side the lesion was located (0.13 %). CONCLUSIONS: Surgeons who have mastered standardized robotic surgical procedures and who understand potential complications and how to prevent them can perform RT safely.

How many sentinel lymph nodes are enough for accurate axillary staging in t1-2 breast cancer?

PURPOSE: During a sentinel lymph node biopsy (SLNB) for breast cancer, the appropriate number of sentinel lymph nodes (SLNs) to be removed for accurate axillary staging is still controversial. We hypothesized that there might be an optimal threshold number of SLNs. We investigated how many SLNs should be removed to achieve an acceptable accuracy and ensure minimal morbidity. METHODS: We reviewed data of 328 patients with invasive breast cancer who underwent SLNB followed by complete level I and II axillary dissection between January 2004 and December 2005. The false negative rate (FNR) and accuracy of SLNB according to the number of removed SLNs were evaluated. RESULTS: The mean number of SLNs removed was 3.0 (range, 1-14), and that of total retrieved axillary lymph nodes was 17.5 (range, 10-40). In total, 111 (33.8%) patients had positive nodes on the permanent pathological report. Among them, 12 patients had negative SLNs; thus, the overall FNR of SLNB was 10.8% (12/111) and the accuracy was 96.3% (316/328). The FNR was 26.6% for a single SLN, 8.0% for two, and 11.1% for three. In cases where four or more SLNs were removed, the FNR decreased to 0% and accuracy reached 100%. CONCLUSION: Our data suggest that a SLNB should not only remove one or two of the hottest node(s) when other hot nodes exist. We also suggest that four might be an optimal threshold number of SLNs to be removed and that removal of more than four SLNs does not improve axillary staging accuracy.