Yeo-Hoon Yoon

Predictive Factors For Ipsilateral or Contralateral Central Lymph Node Metastasis in Unilateral Papillary Thyroid Carcinoma

Objectives:To investigate the incidence and the risk factors for occult ipsilateral or contralateral central neck lymph node (LN)metastasis in patients with unilateral papillary thyroid carcinoma (PTC) and a clinically negative neck. Summary Background Data:Elective central lymph node dissection (CLND) in patients with PTC remains controversial. There have been few prospective studies assessing accurate histopathologic information and predictive factors for the presence of metastasis to the ipsilateral or contralateral central compartment of the neck in patients with PTC and clinically negative neck nodes. Methods:We reviewed a prospective protocol of 111 unilateral PTC patients with clinically node-negative necks who have received total thyroidectomy and elective bilateral CLND from 2005 to 2007. The relationships between LN metastasis to the ipsilateral or contralateral central neck compartment and clinico-pathologic factors such as age, sex, size of primary tumor, perithyroidal invasion, lymphovascular invasion, and capsular invasion were analyzed. Results:Occult central neck LN metastasis was present in 54.1% (60/111). Of these patients, bilateral central LN metastases were present in 50% (30/60), unilateral ipsilateral central LN metastasis in 43.3% (26/60), and unilateral contralateral central LN metastasis in 6.7% (4/60). In the univariate analysis, the rate of ipsilateral central LN metastasis was significantly higher in male patients, high risk MACIS score, carcinoma with a maximal diameter of greater than 1 cm, and carcinoma with lymphovascular invasion (P < 0.05). The rate of contralateral central LN metastasis was significantly higher in cases of carcinoma with a maximal diameter of greater than 1 cm, lymphovascular invasion or histologically proven metastasis to the ipsilateral central LN (P < 0.05). Multivariate analysis showed that the tumor size was an independent risk factor for the presence of ipsilateral central LN metastasis, and the presence of ipsilateral central LN metastasis was the only independent predictor for the presence of contralateral central LN metastasis. Conclusions:Unilateral PTC with a maximal diameter of greater than 1 cm is associated with a high rate of ipsilateral central neck LN metastasis. Moreover, ipsilateral central LN metastasis is a potential independent predictor of synchronous contralateral central LN metastasis. These findings suggest that contralateral as well as ipsilateral elective CLND, performed during the initial thyroid operation, may be effective in the management of patients with unilateral PTC having a maximal diameter of greater than 1 cm and ipsilateral central LN metastasis.

Central lymph node metastases in unilateral papillary thyroid microcarcinoma

The indications for and appropriate extent of prophylactic central lymph node (CLN) dissection for clinically node‐negative patients with unilateral papillary thyroid microcarcinoma (PTMC) are unknown.

Prediction of Occult Central Lymph Node Metastasis in Papillary Thyroid Carcinoma by Preoperative BRAF Analysis Using Fine-Needle Aspiration Biopsy: A Prospective Study

CONTEXT Few reports have determined whether preoperative detection of the BRAF V600E mutation in fine-needle aspiration biopsy (FNAB) may influence determination of surgical extent such as prophylactic central lymph node dissection (CLND) in patients with papillary thyroid carcinoma (PTC). OBJECTIVES Our objectives were to investigate whether preoperative BRAF analysis may assist determination of surgical extent, including prophylactic CLND with variable clinicopathological risk factors for central lymph node metastasis, in patients with PTC and clinically node-negative neck. PATIENTS AND METHODS From July 2009 to May 2011, we prospectively enrolled 148 PTC patients with clinically node-negative neck who received a total thyroidectomy and prophylactic CLND. BRAF mutation by pyrosequencing was tested on preoperative FNAB specimens. The relationships between occult central lymph node metastasis and preoperative BRAF mutation or clinicopathological factors were analyzed. Additionally, we assessed the associations between preoperative BRAF mutation status and various clinicopathological characteristics of PTC revealed postoperatively. RESULTS The prevalence of the BRAF V600E mutation was 53.4%, and the rate of occult central lymph node metastasis was 25.7%. Multivariate analysis showed that tumor size over 1 cm [P = 0.006; odds ratio (OR) = 3.559], perithyroidal invasion (P = 0.023; OR = 2.893), and preoperative positive BRAF mutation (P = 0.029; OR = 2.727) were independent risk factors for the presence of occult central lymph node metastasis. BRAF mutation examined in FNAB specimens, compared with the wild-type allele, strongly predicted perithyroidal invasion (48 vs. 29%; P = 0.017), extracapsular spread (65 vs. 45%; P = 0.017), occult central lymph node metastasis (35 vs. 15%; P = 0.004), and advanced TNM stage (44 vs. 28%; P = 0.035). In the multivariate analysis, patients with preoperative positive BRAF mutation were significantly more likely (P = 0.023; OR = 2.848) to have occult central lymph node metastasis. CONCLUSION Preoperative BRAF analysis by FNAB and primary tumor size based on ultrasonography may assist in predicting occult central lymph node metastasis in patients with PTC and clinically node-negative neck.

Prevention of Anterior Glottic Stenosis after Transoral Microresection of Glottic Lesions Involving the Anterior Commissure with Mitomycin C

Objective: To evaluate the effectiveness of topical mitomycin C (MMC) in preventing anterior glottic stenosis (AGS) after transoral microresection of glottic lesions involving the anterior commissure (AC).

Recurrent laryngeal nerve paralysis in patients with papillary thyroid carcinomas: evaluation and management of resulting vocal dysfunction.

BACKGROUND Recurrent laryngeal nerve paralysis (RLNP) occurs in patients with thyroid malignancy. This study prospectively evaluated vocal function and management outcomes of patients with papillary thyroid carcinomas (PTCs) and RLNP. METHODS Of 319 PTC patients, 256 underwent total thyroidectomy with or without neck dissection, 42 underwent lobectomy, and 21 underwent reoperation for recurrent cancers. All patients underwent laryngoscopy and vocal function measurements before and after surgery. Patients with RLNP and poor vocal function underwent voice surgery. RESULTS Temporary and permanent RLNP rates were 2.8% and .9% at nerve-at-risk-based analysis, respectively. Of 28 patients with tumor invasion of RLN, 14 had preoperative RLNP, with 9 of 14 showing voice changes. RLNP was detected in 9 of 291 (3.1%) patients without documented nerve injury; 8 recovered. Nine of 15 patients with RLN section had poor vocal function, which improved in 8 patients after medialization of the unilateral vocal fold. CONCLUSIONS Patients with PTC may have vocal dysfunction from cancer or surgery-related RLNP. Vocal evaluation and management may help improve their vocal function, thus enhancing their quality of life.

Removal of pediatric branchial cleft cyst using a retroauricular hairline incision (RAHI) approach

OBJECTIVE Branchial cleft cyst (BCC) is treated surgically using a transcervical approach, leaving potential cervical scars. This prospective study assessed the outcomes of retroauricular hairline incision (RAHI) approach for BCC excision in children. METHODS Twelve patients with second BCC (age < 18 years) underwent cyst excision via the RAHI approach, with incision along the postauricular sulcus and hairline. The operation time, complications, and subjective satisfaction with incision scars were assessed. RESULTS Mean operation time was 45 +/- 12 min. There were no significant complications, except for temporary hypoesthesia of the earlobe. Hypertrophic scars at incision sites occurred in two patients, but these scars are usually hidden by the natural hair and auricle. Mean subjective satisfaction score regarding incision scars was 8.7 +/- 0.9 out of 10. CONCLUSIONS The RAHI approach may provide good aesthetic results without significant surgical morbidities. This may be an alternative option for the surgical excision of BCC for children and their parents who desire invisible external scars after surgery.

Occult lymph node metastases in neck level V in papillary thyroid carcinoma

BACKGROUND The extent of lateral neck dissection for clinically evident nodal metastases in the lateral neck in a patient with papillary thyroid cancer (PTC) continues to remain controversial. METHODS We reviewed retrospectively the medical records between March 2005 and March 2008 of 70 patients with PTC who underwent therapeutic lateral neck dissections (level II-V) to establish indications for omission of a level V lymphadenectomy. No patient in the study had a clinically positive level V lymph node. Neck dissection specimens were obtained for histologic analysis for node metastasis with respect to the individual neck levels. RESULTS Thirty-four (49%), 52 (74%), and 48 (69%) patients had histologically positive lymph nodes in levels II, III, and IV, respectively. Occult metastases in level V were observed in 11 (16%) patients. Isolated positive level V lymph nodes were never found, while all patients with positive level V lymph nodes had simultaneous positive level IV lymph nodes. In addition, there was no instance of a pathologically positive lymph node in level V without a suspicious metastatic lymph node in level IV by preoperative ultrasonography. In multivariate analysis, simultaneous multilevel involvement (level II, III, and IV) of lymphatic metastases was associated with level V metastasis. CONCLUSION Level V lymphadenectomy may be omitted in the treatment of PTC patients if positive nodes are not found on histologic exam (frozen section analysis) or by ultrasonography in level IV.

Effect of Topical Mitomycin C on the Healing of Surgical and Laser Wounds: A Hint on Clinical Application

OBJECTIVES: Mitomycin C (MMC) is used in otolaryngological surgery to reduce complications from postoperative scarring. However, the effects of MMC on wound healing at different doses and on different wound types have not been fully described. The aim of this study was to evaluate the effects of topical MMC at 2 different doses on the healing of surgical and laser wounds. STUDY DESIGN AND SETTING: This was a randomized study using 20 rabbits. Six full-thickness wounds were made by excision or laser vaporization on the flank skin. The wounds were randomly treated by topical MMC of 0.4 or 1.0 mg/mL or saline for 5 minutes. RESULTS: Re-epithelialization and contraction of the original wounds were significantly delayed by the use of MMC (P < 0.01). The delayed healing effect of MMC was more prominent in the laser wounds than in the excision wounds. MMC inhibited collagen deposition and fibroblast proliferation of wounds on histological analysis. The 2 different concentrations of MMC showed no difference in gross or histological wound healing characteristics. CONCLUSION: Our results showed that MMC delays the healing of wounds as a result of the inhibition of fibrosis, especially for laser wounds.

Clinical and histologic features of inverted papilloma–associated malignancy

The objectives of the study were to analyze the clinical features of inverted papillomas (IP) associated with malignancy and to evaluate the correlation of tumor stage, survival and histolologic features. We conducted a retrospective review of 18 IP associated with malignancy patients. In addition, we compared histopathologic characteristics (tumor differentiation and malignant cell proportion) with clinical outcomes. Eleven of the tumors were present on the nasal cavity and 7 on the maxillary sinus. The rates of synchronous and metachronous malignancy were 10.1 and 1.1%, respectively. The disease-free survival rate was 83.3%. The tumors were staged as T1 (5/18), T2 (2/18), T3 (8/18), and T4 (3/18). According to the percentage of the malignant cell in the entire tumor tissue, 4 patients (22%) were in grade I, 4 patients (22%) were in grade II, 3 patients (17%) were in grade III, and 7 patients (39%) were in grade IV. There was no relationship between recurrence- and/or disease-free survival and histologic findings including tumor differentiation and malignant proportion. IP-associated malignancy tends to occur synchronously and have more favorable prognosis compared to other sinonasal malignancy. Furthermore, the proportion of malignant cell to IP and tumor stage seems not to affect the clinical outcome of IP-associated malignancy.

Pattern of expression of cyclooxygenase-2 in malignant transformation of sinonasal inverted papilloma

OBJECTIVE Cyclooxygenases (COXs) are enzymes that catalyze the conversion of arachidonic acid to prostaglandins. Many studies have suggested that COX-2, the inducible form of COX, is important in carcinogenesis. However, little is known about the pattern of expression of COX-2 in a multistep process of malignant transformation of sinonasal inverted papilloma (IP). In this study, we investigated COX-2 expression in IPs, IPs with dysplasia, IPs with squamous cell carcinoma (SCC), and primary SCCs of sinonasal tract. STUDY DESIGN A retrospective study was conducted. SETTING The setting was a tertiary care referral center. SUBJECTS AND METHODS The expression of COX-2 was evaluated by immunohistochemistry in 56, 7, 18, and 17 cases of IPs, IPs with dysplasia, IPs with SCC, and primary SCCs, respectively. Furthermore, we investigated the possible correlation between the expression of COX-2 and clinicopathologic variables in patients with IPs with SCC and primary SCC patients. RESULTS Positive immunoreactivity for COX-2 was observed in 3 (5.4%) of 56 IPs, 7 (38.9%) of 18 IPs with SCC, and 7 (41.2%) of 17 primary SCCs, whereas it was not observed in IPs with dysplasia. The percentage of tumors with COX-2-positive immunostaining was significantly higher in IPs with SCC and primary SCCs compared with benign IPs. There was no significant correlation between the expression of COX-2 and clinicopathologic variables, such as tumor stage, histologic differentiation, and the proportion of malignant areas in patients with IPs with SCC. CONCLUSION Cyclooxygenase-2 may play an important role in the process of malignant transformation from IP to SCC.