IDH1/2 mutations in acute myeloid leukemia

The mutational and epigenetic landscape of acute myeloid leukemia (AML) has become increasingly well understood in recent years, informing on biological targets for precision medicine. Among the most notable findings was the recognition of mutational hot-spots in the isocitrate dehydrogenase (IDH) genes. In this review, we provide an overview on the IDH1/2 mutation landscape in Korean AML patients, and compare it with available public data. We also discuss the role of IDH1/2 mutations as biomarkers and drug targets.Taken together, occurrence of IDH1/2 mutations is becoming increasingly important in AML treatment, thus requiring thorough examination and follow-up throughout the clinical course of the disease.

The Expression of Bcl-2 and Bax in Rat Hepatic Erythropoiesis / 대한해부학회지

Hepatic erythropoiesis is a characteristic event of the fetal liver. Generally, the erythropoiesis shows 4 phases: developing (embryonic day (ED) 10 to 14), maximum flat (ED 14 to 16), decreasing (ED 17 to 20), and disappearing day 1 to 10 after birth. In present study, TUNEL positive erythropoietic apoptotic cells were detected and increased through maximum flat phase, resulting in inducing decreasing phase. These results implicate that apoptosis is involved in the regulation of erythropoiesis in the fetal liver. Interestingly, the Bax over expressed in proerythroblasts and basophilic erythroblasts during developing phase, while Bcl-2 in polychromatic and acidophilic erythroblasts during decreasing phase. Moreover, in contrast to Bcl-2, Bax decreased from ED16, on which few erythropoietic cells were seen transiently. During disappearing phase, Bax increased by 2 to 3 times. But a rapid decline of Bcl-2 expression occurred on 1 day after birth. Thus, these results imply that the Bcl-2 and Bax play a role in proliferation and maturation of the erythropoietic cells by regulating apoptosis of the cells, in the hepatic erythropoiesis.

Comparative Analysis of Diagnostic Tools for Parapharyngeal Tumors / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The parapharyngeal tumors are rare and treated mostly by surgical removal. The preoperative diagnosis of parapharyngeal tumors is very important because the surgical removal of neurogenic tumor, which is the main mass in the parapharyngeal space, can induce severe complications. There are many diagnostic tools for parapharyngeal tumors and their effectiveness are variable. In this study, we focused on the diagnostic accuracy of each diagnostic tool. SUBJECTS AND METHOD: We compared the preoperative diagnostic results with the final pathologic reports of 56 parapharyngeal tumors. Diagnostic tools used were computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography (US), and fine needle aspiration biopsy (FNAB). RESULTS: The diagnostic accuracy of MRI, CT and US was 68.2%, 51.6% and 42.8%, respectively. The sensitivity (83%) and specificity (87.5%) of FNAB for neurogenic tumor are higher than those of MRI (75%, 50%). CONCLUSION: These results suggest that FNAB is the most precise and reliable diagnostic tool and MRI is the most reasonable and effective imaging study.

The Study for Prognostic Factors in Anaplastic Carcinoma of the Thyroid / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Anaplastic carcinoma of thyroid gland is a lethal entity: few patients live more than 12 months following the diagnosis. We retrospectively reviewed the experience with this entity at our institute with respect to prognostic factors influencing survival. MATERIALS AND METHODS: Thirteen cases of anaplastic carcinoma of thyroid gland diagonsed from 1995 to 2000 were analyzed retrospectively. The median age at presentation was 66.2 years; the male/female ratio was 1.17:1: and the most common symptom was a rapidly enlarging neck mass. RESULTS: All but one patient died within one year of diagnosis. Tumor size of less than 7 cm and complete resection of tumor were significant prognostic factors. Patients who had operation with or without radiotherapy and/or chemotherapy survived significantly longer than other patients. Median survival duration was 74 days. CONCLUSION: This study showed that complete resection and multimodal treatment for tumor of size less than 7 cm resulted in prolonged survival for a subgroup of patients with anaplastic thyroid carcinoma.

The Prognostic Value of DNA Flow Cytometry in Patients with Early Primary Oral Cavity and Oropharyngeal Squamous Cell Carcinoma / 대한이비인후과학회지

BACKGROUNDS AND OBJECTIVE: It has been known that tumor size, regional neck metastasis state and tumor thickness are the prognostic factors of oral cavity or oropharyngeal cancer. Additionally, DNA flow cytometry has also been reported to be one of the pronosic factors. We would like to evaluate the prognostic value of DNA flow cytometry in early oral cavity or oropharyngeal squamous cell carcinoma. MATERIALS AND METHODS: We analyzed the relation between tumor thickness or neck metastasis and survival rate in 59 patients with early oral cavity or oropharyngeal cancer. Among those patients, DNA flow cytometry was performed in 28 cases and the prognostic value of the parameters of DNA flow cytometry was analyzed. RESULTS: Overall, a 2-year survival rate of the patients was 90.1%. Neither tumor thickness nor neck metastasis state was related to the overall survival rate. Tumor thickness was not related to neck metastasis state, either. Of the parameters of the DNA flow cytometry, only the S phase fraction of aneuploidy was related to the overall survival rate (p=0.0288). Also the total proportion of aneuploidy was weakly related to the state of neck metastasis (p=0.0518). CONCLUSION: These results indicate that DNA flow cytometry can be used as a good complementary factor for predicting the overall survival or neck metastasis in patients with early primary oral cavity or oropharyngeal squamous cell carcinoma.

Acoustic characteristics of patients undergoing short-term endotracheal intubation with or without thyroidectomy who had no nerve injury / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: We carried out an acoustic analysis to investigate the phonatory characteristics of patients undergoing short-term endotracheal intubation with or without thyroidectomy, and who had no nerve injury. MATERIALS AND METHODS: The patients were divided into two groups, one undergoing thyroidectomy (39 cases) and the other not undergoing thyroidectomy (25 cases). All patients of the thyroidectomy group had undergone thyroidectomy using general anesthesia with endotracheal intubation. All patients of the other group had undergone chronic ear surgery with the same anesthetic method and duration. For the evaluation of voice, preoperative and postoperative acoustic analyses were done. RESULTS: On the acoustic analysis of thyroidectomy group, jitter, shimmer and the vocal range were significantly increased at one day after thyroidectomy. But one month after thyroidectomy, these changes return to statistically insignificant increments, except for shimmer and the vocal range. These acoustical changes were not related to the extent of surgery between total thyroidectomy and hemithyroidectomy. In comparison with acoustical changes after short-term endotracheal intubation, the change of jitter and shimmer of thyroidectomy group did differ significantly. CONCLUSION: Voice alteration after thyroidectomy without nerve injury may be associated with the disturbance of the prelaryngeal musculature. This voice changes emphasize the importance of the extralaryngeal skeleton for pitch control and early intensive speech therapy, especially in patients who need their voice professionally.

The Clinical Application of Voice Analysis in Identifying the Presence of Laryngopharyngeal Reflux in Patients with Pharyngeal Neurosis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Pharyngeal neurosis is a common problem in the otolaryngology clinic. Laryngopharyngeal reflux is suggested as one of the etiologic factors in pharyngeal neurosis. The purpose of this study was to find usefulness of voice analysis in diagnosis of pharyngeal neurosis and correlation between voice analysis and 24-hour ambulatory double-probe pH monitoring. MATERIALS AND METHODS: 42 patients with pharyngeal neurosis underwent fiberoptic laryngoscopy, voice analysis, and 24-hour ambulatory double-probe monitoring. The authors used a computerized acoustic analysis pr-ogram (CSL-MDVP) to measure fundamental frequency, jitter, shimmer, and noise to harmonics ratio. RESULTS: There was a significant difference between the positive group and negative group during 24-hour ambulatory pH monitoring regarding jitter and shimmer. Correlation results were good between voice analysis and 24-hour ambulatory double-probe pH monitoring, poor between fiberoptic laryngoscopy and 24-hour ambulatory double-probe pH monitoring. CONCLUSION: This study showed that when abnormal results in voice analysis were found in patients of pharyngeal neurosis, the probability that 24-hour ambulatory double-probe pH monitoring would be abnormal was high.

The Non-Squamous Cell Cancers of the Larynx / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The majority of laryngeal tumors are known to be SCC (squamous cell carcinoma). Non-SCC (non-squamous cell cancers) of the larynx represent a diverse spectrum of diseases with different prognosis and ratio-nales of management from SCC. Therapeutic options to these tumors depend on their histopathological characteristics and clinical behaviors. The purpose of this study was to assess the unique aspects of the non-SCC and to draw diagnosis and provide management options and prognostic variables. MATERIALS AND METHOD: Eleven non-SCC of the larynx from the 212 patients who were diagnosed with larynx cancer during their 3-year visits from 1997 to 2000 were reviewed retrospectively. RESULTS: The incidence of non-SCC was 5.2%. Pathology of non-SCC revealed 3 cases of malignant lymphoma, 2 cases of verrucous cell carcinoma and neuroendocrine carcinoma one case each of basaloid squamous cell carninoma, salivary duct carcinoma, adenocarcinoma, and spindle cell carcinoma. The most common site of origin was supraglottis (6 case, 56.5%), followed by glottis (4 cases, 36.4%) and subglottis (2 cases, 17.2%). Non-Hodgkin's lymphomas and basaloid squamous cell carninoma were treated by chemotherapy. The remaining cases were treated with surgery followed by postoperative radio-therapy or postoperative chemotherapy. The mean follow-up period was 26.8 months (12-43 months). CONCLUSION: Non-SCC accounts for approximately 5.2% of all malignancies of the larynx. Tissue biopsy is the most important diagnostic tool for the non-SCC of the larynx and the tissue sample must be obtained from the deep portion of the submucosal layer. Except for malignant lymphomas, the combined therapy that includes surgery would be the best method of treatment for non-SCC.

Clinical Study of Sarcomas in Head and Neck / 대한이비인후과학회지

BACKGROUNDS: Head and neck sarcomas constitute a heterogenous group of rare malignant tumors occurring at rare sites. The purpose of this retrospective study is to evaluate the pathologic features, treatment modalities, outcome, patterns of failure, survival, and other prognostic factors. MATERIALS AND METHOD: The medical records of 33 patients whose tumors were diagnosed as head and neck sarcomas and treated at the department of otolaryngology in Asan Medical Center between 1990 to 2001 were reviewed. Potential prognostic factors including age, tumor size, histology, and adjuvant treatment were evlauated. RESULTS: All 33 of histologic classification consist of : rhabdomyosarcoma (10), angiosarcoma (4), spindle cell sarcoma (4), osteosarcoma (3), follicular dendritic cell sarcoma (2), synovial sarcoma (2), chondrosarcoma (2), malignant fibrous histiocytoma (2), hemangiopericytoma (1), leiomyosarcoma (1), unclassified (2). The ratio of male to female was 1.2 : 1 (19 : 14). The median age was 42 years (range 4-78 years). The mean follow-up period was 24.7 months. At 3 years, the disease-specific survival rates for patients with rhabdomyosarcoma were 100% and patients with other types of sarcoma had 78.0% mean survival. Twenty-three patients (70%) had undergone surgical approach with adjuvant chemotherapy or radiotherapy. Five patients had undergone surgical treatment only. The univariate analysis showed that tumor size is one of the most important prognostic factors for the survival. CONCLUSION: The rhabdomyosarcoma showed a better survival rate than other sarcomas of head and neck. Tumor size more or less than 5 cm was important prognostic factor for survival. We could not find the proven treatment guidelines, but surgery may be essential to the treatment for head and neck sarcomas.

Voice and Imaging Analysis After Thyroplasty Type l in the Treatment of Unilateral Vocal Paralysis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES:There are several methods to improve voice quality in the patients with paralyzed vocal cord, such as thyroplasty type I, injection, arytenoid adduction. The goal of surgical medialization of the paralyzed vocal fold is to attain complete glottic closure. The purpose of this study is to evaluate the effectiveness of thyroplasty type I through qualifying the vocal function and glottal gap. MATERIALS & METHODS: We experienced 20 cases of unilateral vocal fold paralysis who underwent thyroplasty type I. We performed preoperative and postoperative videoimage analysis (normalized glottal gap area) and computer-assisted voice analysis in all patients. RESULTS: The glottal gap was significantly reduced after thyroplasty type I. Postoperative voice quality was characterized by an improved pitch and amplitude perturbation (jitter and shimmer), maximum phonation time and subglottic pressure . But noise to harmonic ratio was not improved. CONCLUSION: Thyroplasty type I is an effective method in the point of regaining glottal closure and vocal function.

Effect and Catabolism of All-trans Retinoic Acid in Head and Neck Squamous Cell Carcinoma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: All-trans retinoic acid (RA) is a form of vitamin A analogue that has shown chemopreventive activities in many types of malignancy with the properties that regulate cellular differentiations and suppress malignant proliferations. It is thought that the catabolism of RA is mediated by cytochrome P450RAI (CYP26) and its absorption, effects and catabolism are related to cellular retinol binding proteins (CRBP-I and II) and cellular retinoic acid binding proteins (CRABP-I and II). With eight different squamous cell carcinoma cell lines (AMC-HN-1~-8), we investigated the effects of RA and roles of these proteins in the metabolism and regulatory activity of RA. MATERIALS AND METHODS: Survival fractions of eight AMC-HN cells were analyzed six days after the treating them with 1 nM of RA. Reverse transcription-polymerase chain reactions (RT-PCR) were performed before and 24 hours after the load of 1 nM of RA to detect the expressions of CRBP-I, CRABP-I, CRABP-II, and CYP26. RESULTS: Resistances to RA were detected in AMC-HN-1, -2, -5, and -6 cell lines after RA treatment, and AMC-HN-3, -4, -7, and -8 cell lines showed sensitive responses to RA. Before the addition of RA, expressions of CYP26 were detected in AMC-HN-1, -2, -4, -5, -6, and -7 cell lines and CRBP-I was expressed in AMC-HN-3, 4, 5, 7, and -8. After RA addition, the expressions of CYP26 were enhanced in AMC-HN-2, -5, -6, and -7. In six of eight cell lines, CRABP-I was suppressed and CRABP-II was enhanced after RA treatment. CONCLUSION: These results suggest that CYP26 has a direct correlation with the cellular metabolism of RA in the head and neck squamous cell carcinomas and that CRABP-I and CRABP-II have distinct roles in the regulatory effects of RA. CRBP-I might be an indicator that implies the responsiveness to RA.

Postoperative Results in Adult Patients after Tonsillectomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Although tonsillectomy is one of the most often performed surgeries in Otorhinolaryngology, there has not been any long-term postoperative follow-up studies until now. The authors aimed to validate once more, in a long-term follow up study, the need for performing tonsillectomy. MATERIALS AND METHODS: Medical records of 180 adult patients who have received tonsillectomy were retrospectively studied, and telephone surveys were made to the patients. The telephone questionnaire was designed to find out the postoperative pain, complications such as bleeding, the time each patient took to return to the normal diet and social life, the degree of improvement in the symptoms and the satisfactory rate. RESULTS: The chief complaints were recurrent sore throat. There was no immediate postoperative bleeding, but secondary bleeding occurred in 12.8% of the patients. The postoperative pain scored 7.4 in a scale of one to ten. The average time in returning to the normal diet and the normal life was 17.9, 21.1 days, respectively. Studies in the symptomatic improvement showed almost no or minimal residual symptom in 99% of the patients and about 95% of the patients answered positively in satisfactory category. CONCLUSION: Tonsillectomy caused great pain postoperatively in most of the patients and returning to the normal diet and life took fairly a long time. However, the positive answers about the symptomatic improvement and the high satisfaction rate validates tonsillectomy as an effective surgical treatment for patients with recurrent tonsillitis.

Acoustical Effects of Short-Term Endotracheal Intubation / 대한이비인후과학회지

Background and Objective: Patients often complain of transient hoarseness and dysphagia after undergoing procedures requiring endotracheal intubation. Transient voice changes associated with endotracheal intubation are generally assumed to be a result of vocal fold trauma. This study was designed to characterise vocal changes aftershort-term endotracheal anesthesia using acoustic analysis for monitoring the presence of and recovery from intubation trauma. MATERIAL AND METHODS: Vocal functions of 25 patients undergoing chronic ear surgeries using general anesthesia with endotracheal intubation were analyzed preoperatively and postoperatively. Fundamental frequency, jitter, shimmer, noise to harmonic ratio were measured to assess vocal function. RESULTS: In male, fundamental frequency, jitter, shimmer, noise toharmonic ratio did not differ significantly across recording sessions, although certain predictable trends were apparent. In female, statistically significant decrement in fundamental frequency and increment in jitter and shimmer were found postoperatively (p<0.05). One day after extubation, these change were return to preoperative values. CONCLUSION: Even short-term endotracheal intubation affects acoustic-characteristics of voice and acoustic analysis are sensitive to identify and monitor minor laryngeal trauma due to endotracheal intubation.

Facial Nerve Reconstruction with Nerve Graft following Ablative Parotid Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVE: Sacrifice of the facial nerve may be unavoidable during parotid resections for malignancy. In these cases, facial nerve reconstruction is helpful to minimize postoperative facial dysfunction. Many surgical techniques have been described to improve the dysfunction of facial nerve but immediate nerve suture, or grafting if direct suture is not possible, achieves the best results and allows maximal return of function. MATERIALS AND METHODS: We retrospectively studied 8 patients with parotid malignancies undergoing ablative parotid surgery with sacrifice of the seventh cranial nerve and facial nerve reconstruction with interposition graft between 1992 and 1997. They had been followed up for at least 6 months. Seven patients were reconstructed with simple interposition graft and the other was reconstructed with end-to-side facial-hypoglossal interposition graft. All the patients were treated with adjuvant radiotherapy. Each patient was evaluated on the basis of facial symmetry, eye closure and smile by means of photograph taken on the follow-up visit. RESULT: Facial symmetry, eye closure, and smile were improved satisfactorily in five, six, and four patients respectively. Recovery of patients who have had preoperative facial paralysis exhibited rather poor results. CONCLUSION: Nerve grafting performed immediately after resection of the tumor can provide a significant improvement of function in patients with sacrifice of the facial nerve.