Biomedical subjects

Young-Ik Son

Publications and source records attributed to Young-Ik Son.

16 recordsLinked to original sources

PubMed2007

Use of integrated 18F-FDG PET/CT to improve the accuracy of initial cervical nodal evaluation in patients with head and neck squamous cell carcinoma.

BACKGROUND: We investigated the accuracy of performing cervical nodal evaluation with using integrated (18)F-fluoro deoxyglucose positron emission tomography (PET)/CT for squamous cell carcinoma (SCC) of the head and neck as compared with using PET and contrast-enhanced CT (CECT) alone. METHODS: The presence of metastatic lymphadenopathy in each cervical nodal group (level I-VI) and the nodal (N) classification of 47 patients with SCC of the head and neck were determined by using PET, CECT, and PET/CT, respectively, and the results were verified according to the histopathologic findings. RESULTS: Among the 91 foci that had abnormal uptake on PET, the combined PET/CT images provided additional information over PET for the anatomical localization and lesion characterization of 18 sites (19.8%) in 17 patients (36.2%). PET/CT also showed the best results among the three imaging modalities for the sensitivity, specificity, and accuracy (91.8, 98.9, and 97.1%, respectively) for predicting metastatic nodes on a level-by-level analysis, and PET/CT had a higher accuracy (85.1%) for the pathologic nodal classification over the clinical examinations (68.1%) or PET (70.2%). CONCLUSIONS: Combined PET/CT images are more accurate than the PET or CECT images alone for conducting cervical node evaluation in the patients suffering with head and neck SCC.

Aged↗

PubMed2006

Pharyngo-colostomy with supraglottic partial laryngectomy in caustic oropharyngeal stricture.

We present two cases of chronic caustic stricture from the oropharynx to the entire esophagus combined with laryngeal stricture in which the piriform sinuses were stenosed. The restoration of digestive continuity was accomplished by end-to-end pharyngo-colostomy at the level of the cricoid cartilage through the posterior mediastinal route. Supraglottic partial laryngectomy and pharyngoplasty were done simultaneously for the laryngeal and oropharyngeal stricture. The patients were able to swallow a soft blend diet to regular diet with negligible penetration.

Adult↗

PubMed2006

Treatment for extracranial arteriovenous malformations of the head and neck.

CONCLUSIONS: For extracranial arteriovenous malformations of the head and neck (HNAVMs), in which the nidus was accessible via the percutaneous route, ethanol sclerotherapy was a feasible and safe first-line treatment, although successful outcomes were obtained for only about half of the subjects. For other HNAVMs, surgical excision with embolization may be the best choice of treatment. OBJECTIVE: To suggest a treatment protocol for patients with HNAVMs by comparing the treatment outcomes and complications of ethanol sclerotherapy with those of surgical excision combined with embolization. MATERIAL AND METHODS: Twenty patients who had been diagnosed with HNAVM and treated between 1995 and 2002 were retrospectively reviewed. Ethanol sclerotherapy, surgical excision and embolization were used as treatments, either alone or in various combinations. The treatment outcomes and complications with the different modalities were analyzed. RESULTS: Ethanol sclerotherapy was used for 12 cases, with a success rate of 50.0% and a permanent complication rate of 8.3%. Surgical excision combined with embolization was used for 13 patients. Although all patients achieved successful resolution of their HNAVM after surgical excision, 15.4% suffered from permanent complications. In total, 16/20 patients (80.0%) eventually achieved a > or = 75% reduction in the size of their lesions.

Adolescent↗

PubMed2006

Can [18F]-fluorodeoxyglucose standardized uptake values of PET imaging predict pathologic extrathyroid invasion of thyroid papillary microcarcinomas?

OBJECTIVE: To evaluate the hypothesis that the [F]-fluorodeoxyglucose (FDG) standardized uptake values (SUVs) of positron emission tomographic (PET) imaging can predict pathologic extrathyroid invasion of thyroid papillary microcarcinomas (TPMC) DESIGN: Prospective clinical study. METHOD: From 2004 to 2005, 44 consecutive patients with TPMC (< or =1 cm), confirmed by ultrasonography and aspiration cytology, had FDG PET scans performed. Among them, 66 tumor foci in 41 patients were confirmed to be of less than 1 cm in diameter by the final surgical pathology report. According to the microcarcinoma tumor focus, prediction of pathologic extrathyroid invasion, by clinical variables including sonographic findings and SUVs from PET imaging, was evaluated by the univariate and multivariate logistic regression analysis. RESULTS: : Univariate analysis showed that the tumor site attached to the thyroid capsule and the SUVs of PET imaging could predict pathologic extrathyroid invasion. However, the tumor site attached to thyroid capsule and an age older than 45 were significant predictors by multivariate analysis (P = .001 and P = .036). SUVs from PET imaging were only correlated with the size of tumor (P < 0.001). CONCLUSION: The SUVs from FDG PET imaging alone cannot predict the pathologic extrathyroid invasion in patients with TPMC. However, the ultrasonographic findings, such as tumor site, provide better information about the extrathyroid invasion of TPMC tumor foci.

Adult↗

PubMed2006

Integrated 18F-FDG PET/CT for the initial evaluation of cervical node level of patients with papillary thyroid carcinoma: comparison with ultrasound and contrast-enhanced CT.

OBJECTIVE: To compare the diagnostic accuracy of integrated 18F-fluorodeoxyglucose PET/CT with ultrasonography (US) and contrast enhanced CT (CECT) alone in the initial evaluation of cervical lymph node levels of patients with papillary thyroid carcinoma. PATIENTS AND MEASUREMENTS: From July 2004 to March 2005, 26 consecutive patients with papillary thyroid carcinoma, confirmed by aspiration cytology analysis, underwent US, CECT and PET/CT. The sensitivity, specificity and diagnostic accuracy of the US, CECT and PET/CT studies for the final status of 312 cervical node levels (levels I-V: 260, level VI: 52) were compared by employing a generalized estimating equation test. The final status of cervical node levels was determined by the surgical pathology and follow-up data. RESULTS: At all lymph node levels (levels I-VI), PET/CT showed a sensitivity of 30.4%, a specificity of 96.2% and a diagnostic accuracy of 86.9%. The corresponding values for US and CECT were 41.3%, 97.4%, 89.1% (US) and 34.8%, 96.2%, 87.2% (CECT). Considering only the lateral cervical node group (levels I-V), PET/CT showed a sensitivity of 50.0%, a specificity of 97.0% and a diagnostic accuracy of 92.3%. The corresponding values for US and CECT were 53.9%, 97.9%, 93.5% (US) and 42.3%, 96.6%, 91.2% (CECT). The diagnostic results for US, CECT and PET/CT upon initial evaluation of the cervical lymph nodes did not differ significantly on a level-by-level basis. CONCLUSION: Our preliminary results suggest that integrated PET/CT does not provide any additional benefit when compared to US and CECT for the initial evaluation of cervical node levels in patients with papillary thyroid carcinoma.

Adolescent↗

PubMed2006

Sentinel lymph node radiolocalization with 99mTc filtered tin colloid in clinically node-negative squamous cell carcinomas of the oral cavity.

The objective of this study was to evaluate the feasibility of sentinel lymph node biopsy by using a radiotracer lymphatic mapping technique in patients with squamous cell carcinoma of the oral cavity, and the diagnostic value of this technique. We studied twenty patients with previously untreated squamous cell carcinomas of the oral cavity and N0 necks. After the peritumoral injection of 99mTc filtered tin colloid preoperatively, lymphoscintigraphy and intraoperative mapping using a gamma detector were performed to localize sentinel nodes. An open biopsy of the sentinel node was followed by complete neck dissection. We identified the sentinel nodes in 19 of 20 patients (95.0%) by lymphoscintigraphy and in all (100%) by intraoperative gamma detector. In all cases, the status of the sentinel node accurately predicted the pathologic status of the neck with the false negative rate being 0%. The negative predictive value for the absence of cervical metastases was 100%. In conclusion, our radiolocalization technique of sentinel nodes using 99mTc filtered tin colloid in N0 squamous cell carcinomas of the oral cavity is technically feasible and appears to accurately predict the presence of the occult metastatic disease.

Adult↗

PubMed2005

Sarcomatoid salivary duct carcinoma of the larynx.

The sarcomatoid variant is a rare subtype of salivary duct carcinoma that comprises epithelial and sarcomatoid components. The authors present the first reported case of sarcomatoid salivary duct carcinoma occurring in the larynx, which was successfully treated by partial laryngectomy with ipsilateral neck dissection, with no evidence of recurrence after five years. Microscopic analysis revealed a composite epithelial and sarcomatoid tumour. The epithelial component was characterized by papillary proliferation of glandular and ductal structures lined with multilayered epithelial tumour cells. The sarcomatoid component was characterized by pleomorphic spindle cells with cytologic atypia, accompanied by small lymphoid cells, extensive proliferation of blood vessels and focal myxoid changes. To the best of our knowledge, only one case of sarcomatoid salivary duct carcinoma outside a major salivary gland has been reported previously in the literature, and this is the first report of sarcomatoid salivary duct carcinoma arising from the larynx.

Humans↗

PubMed2005

Muscle tension dysphonia in children: Voice characteristics and outcome of voice therapy.

OBJECTIVE: The main object of this study is to elucidate the voice characteristics and the efficacy of voice therapy in children with muscle tension dysphonia (MTD). METHODS: A retrospective file review was undertaken of eight Korean male children diagnosed as having MTD. All subjects received perceptual, acoustical and laryngoscopic evaluation before and after the treatment. RESULTS: Markedly strained and breathy voices were detected in all patients. Pitch breaks and/or inadequately high or low speaking fundamental frequencies were noticed in five subjects. Laryngoscopic evaluation revealed anteroposterior contraction, false vocal fold approximation, decreased vibration of true vocal folds and incomplete glottal closure. Notably, seven out of eight subjects had bilateral vocal nodules. Voice therapy was focused on the awareness, relaxation, respiration and easy-onset phonation to reduce the tension around the laryngeal muscles. A few sessions of voice therapy resulted in dramatic improvement of their voice quality and pitch adjustment. Hyper-contraction of the supraglottic structures was also relieved. CONCLUSIONS: These findings suggest that the proper diagnosis of MTD in children warrants prompt and favorable responses to voice therapy regardless of coexistence of vocal nodules.

Child↗

PubMed2003

Dendritic cells mediate NK cell help for Th1 and CTL responses: two-signal requirement for the induction of NK cell helper function.

Early stages of viral infections are associated with local recruitment and activation of dendritic cells (DC) and NK cells. Although activated DC and NK cells are known to support each other's functions, it is less clear whether their local interaction in infected tissues can modulate the subsequent ability of migrating DC to induce T cell responses in draining lymph nodes. In this study, we report that NK cells are capable of inducing stable type 1-polarized "effector/memory" DC (DC1) that act as carriers of NK cell-derived helper signals for the development of type 1 immune responses. NK cell-induced DC1 show a strongly elevated ability to produce IL-12p70 after subsequent CD40 ligand stimulation. NK-induced DC1 prime naive CD4+ Th cells for high levels of IFN-gamma, but low IL-4 production, and demonstrate a strongly enhanced ability to induce Ag-specific CD8+ T cell responses. Resting NK cells display stringent activation requirements to perform this novel, DC-mediated, "helper" function. Although their interaction with K562 cells results in effective target cell killing, the induction of DC1 requires a second NK cell-activating signal. Such costimulatory signal can be provided by type I IFNs, common mediators of antiviral responses. Therefore, in addition to their cytolytic function, NK cells also have immunoregulatory activity, induced under more stringent conditions. The currently demonstrated helper activity of NK cells may support the development of Th1- and CTL-dominated type 1 immunity against intracellular pathogens and may have implications for cancer immunotherapy.

CD8-Positive T-Lymphocytes↗

PubMed2003

Type-1 polarized nature of mouse liver CD8alpha- and CD8alpha+ dendritic cells: tissue-dependent differences offset CD8alpha-related dendritic cell heterogeneity.

Interleukin-12 p70 (IL-12p70) is a major dendritic cell (DC)-produced cytokine known to support type-1 T helper (Th1) cells and inflammatory-type immunity. While the ability of DC to produce bioactive IL-12p70 depends on both the DC subtype and the microenvironmental conditions of DC development, the relative contribution of each of these factors remains unclear. Here, we report that in contrast to spleen CD8alpha+ and CD8alpha- DC that show strong differences in their respective IL-12p70-producing capacities, CD8alpha+ and CD8alpha- DC isolated from the liver, a non-lymphoid organ, both efficiently produce IL-12p70 in amounts comparable to spleen CD8alpha+ DC. The IL-12p70-producing capacity CD8alpha+ and CD8alpha- DC from either location is greatly increased following their overnight culture in the presence of granulocyte-macrophage colony-stimulating factor. The elevated production of IL-12p70 by short-term cultured DC correlates with their enhanced expression of CD40 and other costimulatory molecules, and elevated T cell-stimulatory capacity. These data indicate that low IL-12-producing capacity is not an intrinsic property of the CDalpha8- DC subtype, and support the hypothesis that factors such as the site of DC development and maturation stage play a dominant role in defining DC function.

Animals↗

PubMed2002

A novel bulk-culture method for generating mature dendritic cells from mouse bone marrow cells.

We established a novel culture method for generating dendritic cells (DC) from mouse bone marrow (BM) cells. Unfractionated bulk BM cells were cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) for 5-7 days and a DC population was isolated by gradient centrifugation with 14.5% (w/v) metrizamide. Through this method, 30-40 x 10(6)/mouse DC with 85-95% purity was obtained on day 7; this yield was higher than those of conventional DC generated by Inaba's method either with GM-CSF alone (conventional-GM DC) or GM-CSF and IL-4 (conventional-GM/4 DC). Bulk-cultured DC have a more matured phenotype than both conventional-GM and -GM/4 DC as shown by higher expression of CD86, MHC class II and CD40. Functional analyses reveal that (1) bulk-DC show less ability in endocytosis than conventional-GM DC and are comparable in IL-12 p70 production with conventional-GM and -GM/4 DC. (2) Bulk-DC exhibit stronger stimulatory capacity in allogeneic T-cell proliferation than conventional DC. (3) By using ovalbumin (OVA) and OVA-specific T-cell receptor (TCR) transgenic mice (DO11.10) system, OVA protein-loaded bulk-DC stimulated CD4 T cells of DO11.10 mice more than conventional-GM DC and comparable with conventional-GM/4 DC. (4) Furthermore, OVA peptide-pulsed bulk-DC stimulated CD4 T cells more than conventional-GM and -GM/4 DC. These data indicate that bulk-DC are functionally more mature than conventional DC. Taken together, bulk-culture method is a simple technique for generating functionally mature BM-DC in large quantities and high purity.

Animals↗

PubMed2002

Pharyngoesophageal reconstruction with lateral thigh free flap.

BACKGROUND: We evaluated the use of a lateral thigh free flap in pharyngoesophageal reconstruction, which is often overlooked and less widely used despite its distinct advantages. METHODS: This study reviewed the patient's medical records, including the patient's age, gender, histopathologic diagnosis, surgical defects, flap size, flap survival, donor and recipient site complications, and swallowing function and voice rehabilitation. RESULTS: Twelve lateral thigh free flaps were used to primarily reconstruct the pharyngoesophagus in 11 patients after tumor resection from July 1997 to May 1999. Eleven of the 12 flaps (91.7%) were transferred successfully. In one patient, the flap failure occurred as a result of venous thrombosis, and therefore another lateral thigh free flap from the opposite thigh was used 3 days later. The swallowing function was restored in all patients. Prosthetic voice rehabilitation was successfully achieved in all five patients, who primarily underwent tracheoesophageal punctures. No frank fistula or stricture developed. Significant donor site morbidity was not noted. CONCLUSIONS: The lateral thigh free flap is useful and reliable in selected cases of pharyngoesophageal reconstruction and versatile in flap design with favorable functional outcomes of swallowing and voice rehabilitation with minimal donor site morbidity.

Aged↗

PubMed2002

Paucity of dendritic cells in pancreatic cancer.

BACKGROUND: The number of dendritic cells (DC) in the local tumor environment correlates with patient survival in numerous tumors. The relationship of DC infiltration in the tumor microenvironment and prognosis was examined in patients with pancreatic adenocarcinoma. METHODS: Forty-seven pancreatectomy specimens with a diagnosis of pancreatic adenocarcinoma were identified retrospectively and analyzed with the dendritic cell markers S-100 and CD1a. Patient survival was correlated with these markers and with p53, CD3, CD20, CD68, Ki-67. RESULTS: Significant numbers (>3 per high-powered field) of tumor-associated S100(+) or CD1a(+) cells were found in only 2/47 patients (4%). When present, dendritic cells were located outside the margin of the tumor. CD3, CD68, and CD20 positive cells were rare or absent in 96%, 92%, and 93% of the specimens. A correlation with survival and numbers of immune cells could not be made secondary to their rarity. The median survival was 18.9 months. No other indices measured correlated with survival. CONCLUSIONS: In patients with pancreatic adenocarcinoma, there is a paucity of immune cells within the tumor.

Antigens, CD↗

PubMedDate not supplied

The pattern of lymphatic metastasis of malignant tumors in the periorbital area.

BACKGROUND AND OBJECTIVES: The rarity of malignant tumors in the periorbital area makes it difficult to assess the patterns of lymphatic spread and to determine the optimal extent of treatment. The objective of this study was to analyze the patterns of lymphatic metastasis in malignant tumors arising from the periorbital area according to the primary site and to assess the optimal extent of surgical treatment for these tumors. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 8 patients with malignant tumors in the periorbital area from January 1997 to June 2002. The mean duration of follow-up was 27.5 months. Five primary tumors were located in the medial half of the periorbital area, 2 tumors in both medial and lateral halves, and 1 tumor in the lateral half. The pathological diagnoses were 3 squamous cell carcinomas, 2 adenoid cystic carcinomas, 2 sebaceous carcinomas, and 1 basal cell carcinoma. RESULTS: The lymphatic metastasis was observed in 4 of 8 patients who had a relatively large (> or =4 cm) primary tumor or poorly differentiated tumor. Four of 7 tumors involving the medial half of the periorbital area exhibited lymphatic spread to the periparotid lymph node and level II cervical lymph node groups. CONCLUSION: The results of this study suggest that more aggressive management of the parotid area is necessary in malignant tumors arising from the periorbital area, even in the medial half of the periorbital area.

Adult↗

PubMedDate not supplied

Combined treatment with interleukin-18 and low-dose interleukin-2 induced regression of a murine sarcoma and memory response.

Among cytokines applied for immunotherapy of cancer, one of the most successful approaches to date involves systemic delivery of high-dose interleukin (IL)-2. However, the clinical utility of high-dose IL-2 has been limited by significant adverse effects, including vascular leak syndrome. Given this limitation, many attempts to decrease the dosage of IL-2 while maintaining its antitumor therapeutic effects are being made. In this study, the authors observed that combined use of IL-18 and low-dose IL-2 synergistically promoted in vitro proliferation of natural killer cells with up-regulation of IL-2 receptor-alpha and also synergistically stimulated cytolytic activity and interferon-gamma production by these cells. Furthermore, intratumoral injections of these two cytokines completely eradicated day-12 established subcutaneous tumor and induced CD4+-dependent memory in a MCA205 murine tumor model. Observed primary antitumor responses depended largely on natural killer cells and partly on CD8+ T cells. Fas-L pathway and interferon-gamma production were critical in tumor eradication. These results indicate that combined administration of IL-18 and low-dose IL-2 could be a new model for cancer immunotherapy, which probably engages the activation of natural killer cells through interferon-gamma- and Fas-L-dependent pathways.

Animals↗

PubMedDate not supplied

Basal cell adenoma of the parotid gland: characteristics of 2-phase helical computed tomography and magnetic resonance imaging.

OBJECTIVE: The goal of this study was to report the radiologic characteristics of basal cell adenoma of the parotid gland, which is a relatively rare neoplasm. METHODS: A radiology and otolaryngology specialist reviewed the 2-phase helical computed tomography (CT) (n = 6) and/or magnetic resonance (MR) imaging (n = 2) scans of 7 patients with basal cell adenoma. The authors evaluated the imaging characteristics, including tumor size, location, contour and margin, internal density or signal intensity, contrast enhancement pattern, and presence of calcification. The imaging features were then analyzed and correlated with the pathologic findings. RESULTS: All the tumors presented as small (less than 3 cm), well-encapsulated, round or oval masses on CT or MR imaging. On the 2-phase CT scan, the mostly solid-looking tumors (n = 4) showed marked contrast enhancement on the early phase, and there was a subsequent decrease in attenuation on the delayed phase. These tumors were classified as the solid subtype on histologic examination. Meanwhile, the tumors with large cystic areas (n = 2) showed gradual and additional enhancement on the delayed phase and were classified as the tubular or trabecular subtype on pathologic evaluation. There were small spots of low attenuation in the tumors of the solid subtype, which were proved to be intratumoral microcysts in the pathologic correlation. Calcification was found in a tumor. CONCLUSIONS: Basal cell adenomas of the parotid gland present as small well-marginated tumors and appear as masses with central large cysts or solid masses with microcysts on CT and MR imaging scans. Basal cell adenomas of the parotid gland had at least 2 different enhancement patterns on the 2-phase helical CT scans, and the enhancement patterns and imaging architecture were related to the histologic subtype of the tumors.

Adenoma↗