Hyang Ae Shin

Management of Contralateral N0 Neck in Tonsillar Squamous Cell Carcinoma

Objectives: It is well established that tonsillar squamous cell carcinomas have a high probability of disseminating to the neck. An ipsilateral neck treatment is mandatory during initial treatment of stages II to IV tonsillar carcinomas. However, as of yet, no consensus exists whether to perform elective contralateral neck management.

Particle image velocimetry measurements for the study of nasal airflow

Conclusions. Particle image velocimetry (PIV) permits investigation of the distribution and velocity of the airflow in the nasal cavity. During breathing, the main laminar flow stream passes through the middle meatus and turbulent flow can be detected under physiologic conditions. Objectives. Physical models or casts of the nasal cavity have been utilized in several studies in an effort to understand its aerodynamics. PIV is a new technique for measuring the aerodynamic properties of tubular structures. In this article we evaluate nasal airflow characteristics during physiologic breathing under normal conditions and the usefulness of PIV. Material and methods. A nasal model cast obtained by a combination of rapid prototyping and solidification of clear silicone was connected to a pump which simulated the physiological pressure in the upper airway system. A glycerol–water mixture was used as the flow material. The airstream was marked with spherical polyvinyl particles, observed through solidified clear silicone and analyzed using PIV. Results. The main flow within the cavity, which was mostly laminar, passed through the middle meatus. Turbulence was clearly visible in the anteroinferior part of the middle turbinate. The flow rate was highest at the middle meatus during inspiration and expiration.

Diallyl sulfide induces growth inhibition and apoptosis of anaplastic thyroid cancer cells by mitochondrial signaling pathway

Anaplastic thyroid carcinoma (ATC) is one of the most lethal solid tumors arising thyroid gland with dismal prognosis. One of the constituents of garlic, diallyl sulfide (DAS) was shown to inhibit chemically induced carcinogenesis in many animal models. This study examined whether DAS could induce growth inhibition and apoptosis in ATC cells. In MTT assay, DAS treatment inhibited the proliferation of ARO cells in a dose-dependent manner. Flow cytometric analysis showed that DAS treatment increased the accumulation of sub-G1 DNA and concomitant accumulation of cells in the G2/M phase in a dose-dependent manner. In addition, DAS-induced apoptosis was associated with a decrease in the level of Bcl-2 expression and an increase in the level of Bax expression, and cytochrome c was remarkably released from mitochondrial into the cytosol by DAS. Furthermore, caspase-9 and caspase-3 were activated by DAS, and DAS cleaved PARP. Taken together, DAS decreased cell proliferation and induced apoptosis via mitochondrial signaling pathway in ATC cells.

Role of primary surgery for early-stage (T1–2N0) squamous cell carcinoma of the oropharynx

To evaluate treatment outcomes and the role of primary definitive surgery for T(1-2), clinically N(0) oropharyngeal squamous cell carcinoma (OPSCC) patients, we performed a retrospective analysis of 46 consecutive cases treated primarily by surgery and/or postoperative radiotherapy at Yonsei University between May 1992 and December 2006. Twelve patients were T(1) and 34 were T(2). The most common location was the tonsil (54%), followed by the soft palate (19%), the base of the tongue (BOT) (15%) and the posterior wall (12%). Occult lymph node metastasis was noted in 12 cases (26%). Seventeen patients (37%) received adjuvant radiotherapy. The 5-year disease-specific survival rate (DSSR) was 83%: 100% for clinical stage I (T(1)N(0)) and 74% for clinical stage II (T(2)N(0)). The 5-year DSSR of patients with surgery alone was 86%. Thirteen of 14 patients (93%) treated with conservative surgery alone without mandible-splitting or adjuvant radiotherapy attained disease-free status. In addition, 25 of 40 patients (63%) with disease-free status were treated with surgery alone. Almost 30% of all patients may be candidates for adjuvant chemotherapy through histopathologic analysis according to the National Comprehensive Cancer Network (2007) guidelines. The results of the present study demonstrate excellent oncologic outcomes with primary surgery for the treatment of early-stage OPSCC and suggest that surgery offers the best opportunity to identify patients in whom adjuvant radio- or chemotherapy may be most appropriately applied.

Effect of Epicatechin against Radiation-Induced Oral Mucositis: In Vitro and In Vivo Study

Purpose Radiation-induced oral mucositis limits the delivery of high-dose radiation to head and neck cancer. This study investigated the effectiveness of epicatechin (EC), a component of green tea extracts, on radiation-induced oral mucositis in vitro and in vivo. Experimental Design The effect of EC on radiation-induced cytotoxicity was analyzed in the human keratinocyte line HaCaT. Radiation-induced apoptosis, change in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) generation and changes in the signaling pathway were investigated. In vivo therapeutic effects of EC for oral mucositis were explored in a rat model. Rats were monitored by daily inspections of the oral cavity, amount of oral intake, weight change and survival rate. For histopathologic evaluation, hematoxylin-eosin staining and TUNEL staining were performed. Results EC significantly inhibited radiation-induced apoptosis, change of MMP, and intracellular ROS generation in HaCaT cells. EC treatment markedly attenuated the expression of p-JNK, p-38, and cleaved caspase-3 after irradiation in the HaCaT cells. Rats with radiation-induced oral mucositis showed decreased oral intake, weight and survival rate, but oral administration of EC significantly restored all three parameters. Histopathologic changes were significantly decreased in the EC-treated irradiated rats. TUNEL staining of rat oral mucosa revealed that EC treatment significantly decreased radiation-induced apoptotic cells. Conclusions This study suggests that EC significantly inhibited radiation-induced apoptosis in keratinocytes and rat oral mucosa and may be a safe and effective candidate treatment for the prevention of radiation-induced mucositis.

Endoscopic axillo-breast approach for benign neck mass excision†

Benign neck masses are usually found in younger patients, who are more likely to be concerned about postoperative scars. Until recently, a direct approach through a transcervical incision along the mass has been accepted as a standard surgical procedure for the benign neck mass. However, this conventional transcervical approach leaves a visible scar on the neck, regardless of the size of the incision. We assumed that an endoscopic gasless axillo‐breast (A‐B) approach might be a good alternative method for excision of benign neck masses. The aim of this study was to determine the safety and feasibility of a gasless A‐B approach for the excision of benign neck masses by comparing it to the conventional open approach.

The effect of allergen provocation on the nasal cycle estimated by acoustic rhinometry

CONCLUSION The overall duration and reciprocity of the nasal cycle were not changed after allergen provocation. The duration of immediate response was 38 min, but the amplitude of the nasal cycle was increased significantly after allergen provocation. OBJECTIVE Nasal airflow is asymmetrical and subjected to spontaneous reciprocal changes which are referred to as the nasal cycle. Limited information is available on how this is affected by allergens. The purpose of this study was to evaluate the effects of allergen provocation on the nasal cycle. MATERIALS AND METHODS This study was performed on 25 patients with allergic rhinitis and 25 subjects in a control group with no symptoms of allergic rhinitis. Acoustic rhinometry was used to test patients before and after allergen provocation. The patients underwent acoustic rhinometry at 15-min intervals for evaluation of nasal cycle and 3-min intervals for immediate response. RESULTS With the allergic patients, 21 of the 25 patients (84.0%) showed a nasal cycle and they still had a nasal cycle after the allergen provocation. In the study on the changes in the immediate responses, the average recovery time was 38 min and the reduction rate of the non-patent side was higher than that of the patent side. Also, the average period of the nasal cycle was 153 min before the allergen provocation and 140 min on average after the allergen provocation; there were no statistical differences. The amplitude of each nasal cycle increased after allergen provocation and the difference had statistical meaning.Conclusion. The overall duration and reciprocity of the nasal cycle were not changed after allergen provocation. The duration of immediate response was 38 min, but the amplitude of the nasal cycle was increased significantly after allergen provocation. Objective. Nasal airflow is asymmetrical and subjected to spontaneous reciprocal changes which are referred to as the nasal cycle. Limited information is available on how this is affected by allergens. The purpose of this study was to evaluate the effects of allergen provocation on the nasal cycle. Materials and methods. This study was performed on 25 patients with allergic rhinitis and 25 subjects in a control group with no symptoms of allergic rhinitis. Acoustic rhinometry was used to test patients before and after allergen provocation. The patients underwent acoustic rhinometry at 15-min intervals for evaluation of nasal cycle and 3-min intervals for immediate response. Results. With the allergic patients, 21 of the 25 patients (84.0%) showed a nasal cycle and they still had a nasal cycle after the allergen provocation. In the study on the changes in the immediate responses, the average recovery time was 38 min and the reduction rate of the non-patent side was higher than that of the patent side. Also, the average period of the nasal cycle was 153 min before the allergen provocation and 140 min on average after the allergen provocation; there were no statistical differences. The amplitude of each nasal cycle increased after allergen provocation and the difference had statistical meaning.

Radioprotective effect of epicatechin in cultured human fibroblasts and zebrafish.

Radiation-induced normal cell damage limits the delivery of high-dose radiation to targeted cancer. This study investigated the effect of epicatechin (EC), a minor component of green tea extracts, on radiation-induced cellular damage in vitro in primary cultured human fibroblasts and in vivo in a zebrafish model. Cell viability, proliferation and wound-healing efficacy, mitochondrial membrane potential, and reactive oxygen species (ROS) generation as well as changes in the signaling pathway related to apoptosis were investigated in fibroblasts. The therapeutic effects of EC were explored in a zebrafish model. EC increased clonogenic survival and restored the migration ability of the fibroblasts after irradiation. EC inhibited radiation-induced ROS generation, mitochondrial dysfunction and cell death. EC significantly reduced the expression of p-JNK, p-38, and cleaved caspase-3 compared with their significant increase after radiation treatment. EC attenuated the radiation-induced embryotoxicity in a zebrafish model. These results suggest that EC represents an effective means of reducing cellular damage and facilitating wound healing after radiation exposure.

Clinical Significance of Vibration-Induced Nystagmus

The aims of the study were to characterize the vibration-induced nystagmus (VIN) in patients with unilateral vestibular neuritis (VN) and Ménière’s disease (MD), and to clarify the clinical significance of VIN by comparing it with caloric results in patients with VN and MD. We recorded eye movements from 22 VN patients and 24 MD patients using unilateral 100-Hz vibration on the mastoid bone. Eye movements were analyzed and the maximum value of slow-phase eye velocity was obtained during vibration on each mastoid. The average value of slow-phase velocities was calculated. Spontaneous nystagmus was subtracted from the slow-phase velocity, whenever it was present. A canal paresis (CP) greater than 25% was considered pathologic. All but one VN patient showed pathologic CP with the direction of the slow-phase eye movement of VIN toward the lesioned side. Fifteen (63%) out of 24 MD patients showed VIN with the slow-phase eye movement directed to the lesioned side. Pathologic CP was present in 9 (38%) out of 24 MD patients and 8 of them showed slow-phase eye movements of VIN directed to the lesioned side. There were also 8 other MD patients who showed slow-phase eye movement of VIN directed to the intact side. Among them, 3 patients with the slow-phase eye movement more than 5°/s showed CP on the intact side. The amplitude of slow-phase eye velocity showed a significant correlation with CP in patients with either VN or MD. There was no significant difference in the slope of the regression lines between the VN and MD groups. Our results suggest that VIN may probe imbalance of canal responses to low-frequency stimulation similar to the caloric test. It also shows that VIN can help in detecting vestibular imbalance using a stimulation mechanism different from the caloric test. The VIN test can be helpful in determining the lesioned side in patients with VN; however, it has some limitations in localizing the lesioned side in patients with MD.

Larynx-Preserving Partial Pharyngectomy via Lateral Pharyngotomy for the Treatment of Small (T1~2) Hypopharyngeal Squamous Cell Carcinoma

Objectives To evaluate the oncologic and functional results of larynx-preserving partial pharyngectomy (LPP) via lateral pharyngotomy approach as a primary treatment for small (T1 or T2) hypopharyngeal squamous cell carcinoma (HPSCC). Methods We performed a retrospective review of 23 patients who underwent LPP through lateral pharyngotomy approach for small HPSCC at the our department between January 1991 and June 2007. Fourteen (61%) patients had adjuvant postoperative radiotherapy. Results The 2-years and 5-years disease specific survival rate was 77% and 61%, respectively. Nine patients (39%) had tumor recurrence. The most common pattern of recurrence was isolated distant failure (n=4, 44%) followed by local (n=2, 22%) and loco-regional (n=3, 34%) recurrence. The ultimate cure rate of the primary tumor was 87% (20 of 23). Twenty-two of the 23 patients (95%) could be decannulated, tolerate an oral diet, and had acceptable postoperative phonatory function. Conclusion LPP via lateral pharyngotomy approach appears to be a feasible procedure for selected small HPSCC patients in terms of both oncologic and functional outcomes.