Yoon Kyoung So

Prophylactic central lymph node dissection for clinically node-negative papillary thyroid microcarcinoma: Influence on serum thyroglobulin level, recurrence rate, and postoperative complications

BACKGROUND In papillary thyroid microcarcinoma (PTMC), regional lymph node metastasis (LNM) is associated with a increased locoregional recurrence rate. Yet, prophylactic central lymph node dissection (CLND) targeting subclinical central LNM continues to be a matter of debate in the treatment of PTMC, which generally carries an excellent prognosis. The aim of our study was to investigate the benefits and risks of prophylactic CLND in patients with clinically node-negative PTMC. METHODS This study included 232 patients who underwent surgery for clinically node-negative PTMC from 1999 to 2006. Of these 232 patients, 113 underwent only total thyroidectomy (TT) and 119 underwent TT in conjunction with prophylactic bilateral CLND (TT with CLND). We then compared serum thyroglobulin (Tg) levels, recurrence rates, and postoperative complications between the 2 groups (TT only and TT with CLND). RESULTS The postoperative stimulated serum Tg level was significantly less in the TT with CLND group than in the TT only group (1.07 vs. 2.24 ng/mL, respectively; P = .022). The stimulated Tg levels in the 2 groups became similar, however, after low-dose radioactive iodine treatment (0.44 ng/mL vs. 0.69 ng/mL, respectively; P = 0.341). There was no significant difference in 3-year locoregional control rates after TT with CLND and TT only (98.3% vs. 96.5%, respectively; P = .368). Although the frequency of permanent hypocalcemia was approximately 3 times greater in the TT with CLND group (5.6%) than in the TT only group (1.8%), this finding did not reach statistical significance. CONCLUSION With prophylactic CLND, the postoperative Tg level can significantly decrease. However, prophylactic CLND is not helpful in decreasing short-term locoregional recurrence in patients with clinically node-negative PTMC. Finally, the risk of permanent hypocalcemia may increase after CLND.

Preoperative BRAF Mutation Has Different Predictive Values for Lymph Node Metastasis according to Tumor Size

Objective. To investigate whether BRAF mutation of papillary thyroid carcinoma (PTC) has different predictive values for regional lymph node (LN) metastasis according to tumor size. Study Design. Prospective cohort study. Setting. A tertiary hospital. Subjects and Methods. From January 2009 to August 2009, the authors prospectively enrolled 102 consecutive patients with unifocal PTC based on the findings of ultrasonography-guided fine-needle aspiration biopsy (FNAB). BRAF mutation was tested on preoperative FNAB specimens. Total thyroidectomy and bilateral central neck dissection (± lateral neck dissection) was performed for all patients. Among 102 patients, 71 who were confirmed to have unifocal PTC by the surgical pathology were finally selected. The 71 patients were classified into 3 groups according to their tumor size: group I, ≤0.5 cm; group II, >0.5 cm and ≤1 cm; and group III, >1 cm. LN metastasis was evaluated in the surgical specimen as a dependent variable. The authors investigated whether BRAF mutation is predictive of LN metastasis in each group. Results. Overall, BRAF mutation was a significant predictor of LN metastasis (P = .045). When patients were classified into 3 groups, frequency of LN metastasis increased with tumor size: 4.8%, 50.0%, and 66.7% (P < .001). However, the frequency of BRAF mutation was not different among 3 groups: 61.9%, 56.3%, and 72.2% (P = .536). BRAF mutation was predictive of LN metastasis only in group II (P = .026). Conclusion. BRAF mutation of PTC may have differential predictive values for LN metastasis, according to tumor size.

Multifocality and Bilaterality of Papillary Thyroid Microcarcinoma

Objectives Papillary thyroid carcinomas frequently occur as two or more separate foci within the thyroid gland (18%-87%). However, those multifocal tumors are easy to be undetected by preoperative radiologic evaluations, which lead to remnant disease after initial surgery. We aimed to study the incidence of multifocal papillary thyroid microcarcinomas (PTMCs), diagnostic accuracy of preoperative radiologic evaluation, predictive factors, and the chance of bilateral tumors. Methods Two hundred and seventy-seven patients with PTMC were included in this study. All patients underwent total thyroidectomy as an initial treatment. Medical records, pathologic reports, and radiological reports were reviewed for analysis. Results Multifocal PTMCs were detected in 100 of 277 patients (36.1%). The mean number of tumors in each patient was 1.6±1.1, ranging from 1 to 10. The additional tumor foci were significantly smaller (0.32±0.18 cm) than the primary tumors (0.63±0.22 cm) (P<0.001). There was no significant relationship between primary tumor size and the presence of contralateral tumors. With more tumors detected in one lobe, there was greater chance of contralateral tumors; 18.8% with single tumor focus, 30.2% with 2 tumor foci, and 46.2% with 3 or more tumor foci in one lobe. Sensitivity of preoperative sonography was 42.7% for multifocal tumors and 49.0% for bilateral tumors. With multivariate analysis, nodular hyperplasia was the only significant factor for multifocal tumors. Conclusion In cases of PTMCs, the incidence of multifocal tumors is high. However, additional tumor foci are too small to be diagnosed preoperatively, especially under the recent guidelines on radiologic screening tests for papillary thyroid carcinoma. Multifocal PTMCs have high risk of bilateral tumors, necessitating more extensive surgery or more thorough follow-up.

Expression of sodium-iodide symporter and TSH receptor in subclinical metastatic lymph nodes of papillary thyroid microcarcinoma.

BackgroundThe clinical significance of the subclinical lymph node (LN) metastasis in clinically node-negative (cN0) papillary thyroid microcarcinoma (PTMC) has been debated. We investigated the expression of sodium–iodide symporter (NIS) and thyroid-stimulating hormone receptor (TSHR) in the subclinical metastatic LNs of PTMC, which are crucial prerequisites for the response to radioactive iodine treatment.MethodsAmong 149 consecutive patients who received total thyroidectomy in conjunction with prophylactic central neck dissection for cN0 PTMC from October 2005 to December 2007, 20 who had single PTMC and subclinical LN metastasis (cN0, pN1, single PTMC) were included. Immunohistochemical staining was performed with anti-human NIS antibody and anti-human TSHR antibody in 20 primary tumors and 52 metastatic LNs.ResultsNIS and TSHR expression was detected in 19 (95%) and 18 (90%) of 20 PTMCs, respectively. NIS and TSHR expression were also detected in 50 (96.2%) and 39 (75%) of 52 metastatic LNs, respectively. In 85% of patients, the presence of NIS expression in primary PTMCs was concordant with that in corresponding metastatic LNs. Intensities of NIS and TSHR expression were diverse. In 6 of 12 cases of multiple metastatic LNs, the metastatic LNs showed heterogeneous intensities of NIS expression.ConclusionsThe presence of NIS and TSHR expression was observed with high frequency in both PTMCs and corresponding subclinical metastatic LNs. However, the intensity of NIS and TSHR expression was diverse. Multiple metastatic LNs from single primary tumor focus could have heterogeneous intensity of NIS expression.

Inflammatory myofibroblastic tumor involving ear lobule

We present herein an extremely rare case of an inflammatory myofibroblastic tumor (IMT) of the ear lobule with its management. A 50-year-old woman presented with a wart-like mass between the ear lobule and the facial skin. She had been accidentally lacerated her left ear lobule and visited our clinic. The mass had been incidentally found by the patient 1 year before the trauma and growing slowly without pain. Surgical excision and primary closure was performed. Histopathologic examination demonstrated ill-defined margined nodular proliferation of spindle cells in deep dermis with focal stromal hyalinization and lymphoplasmacytic infiltration compatible with the IMT. The patient showed no evidence of recurrence 6 months after surgery. To our knowledge, this is the first report of an IMT occurred in the external ear. Auricular IMT of our case was not aggressive in clinical nature and treated optimally with surgical excision.

Prognostic Role of Neutrophil-to-Lymphocyte Ratio in Patients with Human Papillomavirus–Positive Oropharyngeal Cancer

Objective To investigate the prognostic impact of the neutrophil-to-lymphocyte ratio (NLR) for human papillomavirus–positive oropharyngeal cancer (HPV+ OPC). Study Design Retrospective institutional database analysis. Setting Tertiary referral medical center. Material and Methods In total, 104 patients with HPV+ OPC were enrolled. From the blood laboratory data checked within 4 weeks before initiation of primary treatment, NLR was calculated. The association between clinicopathological characteristics and NLR was analyzed, and the prognostic role was evaluated based on overall survival (OS) and disease-free survival (DFS). Results According to the cutoff value (2.42) for NLR, the patients were classified into the low NLR group (n = 61) or the high NLR group (n = 43). High NLR was associated with a higher rate of advanced T classification (P = .007) and diabetes mellitus (P = .01). The proportion of surgery-based treatment was lower in the high NLR group (20.9% vs 42.6%, P = .02). The high NLR group showed a lower 5-year OS rate (85.3% vs 96.3%, P = .09) and a lower 5-year DFS rate (68.1% vs 94.7%, P = .01) than those in the low NLR group. Multivariate analysis showed that advanced N classification was a significant predictor for worse 5-year OS (hazard ratio [HR], 17.40; 95% confidence interval [CI], 2.36-128.29) and that both advanced N classification (HR, 7.78; 95% CI, 2.33-25.93) and high NLR (HR, 4.16; 95% CI, 1.24-13.95) were important prognosticators for worse 5-year DFS. Conclusion Elevated pretreatment NLR was associated with poor DFS in patients with HPV+ OPC.

Lateral lymph node metastasis in papillary thyroid carcinoma: A systematic review and meta-analysis for prevalence, risk factors, and location

BACKGROUND Lymph node metastasis (LNM) is frequent in papillary thyroid carcinoma (PTC) and is associated with a poor prognosis. Unlike central LNM (CLNM), there are few studies focusing on LLNM. We aimed to investigate the prevalence and the risk factors for LLNM, with its most prevalent sites. METHODS We performed a comprehensive literature search using the PubMed and EMBASE databases for relevant studies published prior to November 2016 that examined the risk factors for LLNM. RESULTS Twenty-three studies, including 18,741 patients, were included. The prevalence of LLNM was 20.9% in all patients. CLNM (pooled OR = 7.84, 95% CI = 6.13-10.02, p < .0001), extrathyroidal extension (pooled OR = 3.22, 95% CI = 2.21-4.70, p < .0001), tumor multifocality (pooled OR = 2.19, 95% CI = 1.67-2.89, p < .0001), male sex (pooled OR = 1.72, 95% CI = 1.50-1.98, p < .0001), upper pole location (pooled OR = 2.96, 95% CI = 1.93-4.53, p < .0001), tumor size ≥1.0 cm (pooled OR = 2.49, 95% CI = 1.71-3.61, p < .0001), lymphovascular invasion (pooled OR = 3.96, 95% CI = 2.61-6.03, p < .0001) and tumor bilaterality (pooled OR = 1.31, 95% CI = 1.12-1.53, p = .0006) were significantly associated with LLNM. Most frequently affected areas were levels III and IV. CONCLUSIONS The prevalence of LLNM was high although the prognostic impact is unknown. The significant risk factors for LLNM were not much different from known risk factors for CLNM.

Efficacy of postoperative neck irradiation for regional control in patients with pN0 oral tongue cancer: Propensity analysis

The purpose of this study was to investigate whether adjuvant radiotherapy (RT) is efficacious for regional control and survival in patients with pN0 oral tongue cancer.