An Analysis of Prognostic Factors Affecting the Outcome of Radiation Therapy for Nasopharyngeal Carcinoma / 대한방사선종양학회지

PURPOSE: This retrospective study was conducted to analyze the treatment results and to evaluate the prognostic factors affecting the survival of nasopharyngeal carcinoma patients. MATERIALS AND METHODS: From 1987 to 2002, we analyzed 43 patients who had nasopharyngeal carcinomas that were histologically confirmed and who had also completed the planned radiation therapy course at Keimyung University Dongsan Medical Center. According to the 6th edition of American Joint Committee on Cancer staging system, 12 patients (27.9%) were at Stage II, 13 (30.2%) were at Stage III and 18 (41.9%) were at Stage IV. Histopathologically, there were 15 (34.9%) squamous cell carcinomas, 8 (18.6%) nonkeratinizing carcinomas, 17 (39.5%) undifferentiated carcinomas, and 3 (7.0%) lymphoepitheliomas. Among the total 43 patients, 31 patients (72.1%) were treated with only radiation therapy. Neoadjuvant chemotherapy was performed on 7 patients (16.3%) and concurrent chemoradiotherapy was performed on 5 patients (11.6%). Cisplatin and 5-Fluorouracil were administered to 11 patients for 4 cycles, and Cisplatin and Taxotere were administered to 1 patient for 6 cycles. The range of the total radiation dose delivered to the primary tumor was from 61.2 to 84 Gy (median 70.4 Gy). The follow-up period ranged from 2 to 197 months with median follow-up of 84 months. RESULTS: The local control rate at 6 months after radiation therapy was 90.7%. The five year overall survival and disease free survival rates were 50.7% and 48.9%, respectively. On the multivariate analysis, the age, T-stage (T1-3 vs T4), N-stage and AJCC stage were the statistically significant prognostic factors affecting survival (p<0.05). The patterns of failure were as follows: local failure only in 3 patients (7.0%), local and systemic failure in 1 patient (2.3%), and distant metastasis only in 11 patients (25.6%). CONCLUSION: The prognostic factors affecting the outcome of nasopharyngeal carcinoma were age, T-stage (T1-3 vs T4), N-stage and stage. Because systemic metastasis was the main failure pattern noted for nasopharyngeal carcinoma, systemic chemotherapy is needed to decrease the rate of distant metastasis for nasopharyngeal carcinoma. In addition, research for more effective chemotherapeutical regimens and schedules is also needed.

Malignant Melanoma of the Vagina: A Report of 2 Cases / 대한방사선종양학회지

Primary malignant melanoma of the vagina is an extremely rare genital neoplasm occurring mainly in postmenopausal women. It has a worse prognosis than cutaneous melanomas, because of the high rate of loco- regional recurrences and rapid systemic dissemination. In the past, radical surgical extirpation as the primary management had been recommended to improve loco-regional control, and possibly overall survival. However, the prognosis was poor in spite of such a radical approache. Recently, more conservative treatment such as wide local excision combined with adjuvant high-dose fraction radiotherapy seems to have promising results. Primary radiation therapy could be served as an alternative to surgery for patients with lesion less than 3 cm in diameter. We report 2 cases of primary vaginal malignant melanoma treated with radiotherapy.

The Association of Job Characteristics and Stress Indicators in TV Manufacturing Plant Workers / 대한산업의학회지

This study was conducted to evaluate the association of job characteristics and stress indicators, from May 1st to 10th, 1996. The study population was 210 workers (clerical workers, 67; engineers, 82; assembly line workers, 61) engaged in a television manufacturing company. A questionnaire method was used to collect the data regarding to job demand, job control, behavioral type, life style and psychiatric symptoms. Clinical examination was conducted to measure blood pressure, serum cholesterol, fasting blood sugar and HbA1c. Percentage of high subjective job strain group was significantly higher in clerical workers(9.0 %) than in engineers(4.9 %) and in assembly line workers(3.3 %) (p < 0.01). Mean values of fasting blood sugar and HbA1c were significantly different between types of occupation and were the highest in clerical workers (p < 0.05). Significant association was found between perceived job characteristics and psychiatric symptom score (p < 0.01). The more job demand and the less job control was, the higher psychiatric symptom score was reported. Diastolic blood pressure was significantly related to job control (p < 0.05). The more job control was, the higher blood pressure was reported. In multiple regression analysis, job demand, job control and age were significant variables explaining the psychiatric symptoms and R2 was 0.23. Perceived job characteristics and type of occupation were not significant in explaining diastolic blood pressure and cholesterol. Type of occupation, job demand, age and BMI were significant variables explaining lasting blood sugar and R2 was 0.25. Type of occupation was the only significant variable explaining HbA1c and R2 was 0.07. According to this result, occupational type and subjective job characteristics must be considered in study of job stress. As a result of multiple analysis, subjective job characterics are significantly related to psychiatric symptoms and type of occupation is significantly related to fasting blood sugar and HbA1c.

Relationship of Physical Fitness with Age and Body Fat, Work Pattern, Life Style among Male Workers of an Electronic Manufacturing Company / 대한산업의학회지

This is pilot study to evaluate the relationship of physical fitness with age, body fat, work pattern and life style among 20-9 aged male workers (n=417). Physical fitness was measured by maximum oxygen uptake, forced vital capacity, 1 second forced expiratory volume, grip strength, back strength, sit ups and trunk flexion. Life style was self-reported on a questionnaire about regular exercise, smoking, alcohol consumption, coffee consumption, degree of stress, and percent of body fat measured by bioelectrical impedance fat meter. Age was significantly and negatively related to physical fitness except grip strength. Obesity was next to most significant factor for physical fitness, it was associated with maximum oxygen uptake, grip strength, back strength, trunk flexion. Regular exercise was associated with maximum oxygen uptake. Others was insignificantly related to physical fitness. Performance of physical fitness test was significantly correlated with age, obesity and regular exercise.

The Effect of VDT Work on Vision and Eye Symptoms among Workers in a TV Manufacturing Plant / 예방의학회지

This study was conducted to evaluate the effect of VDT work on eyes and vision among workers in a TV manufacturing plant. The study subjects consisted of 264 screen workers and 74 non-screen workers who were less than 40 years old male and had no history of opthalmic diseases such as corneal opacities, trauma, keratitis, etc and whose visual acuity on pre-employment health examination by Han's test chart was 1.0 or above. The screen workers were divided into two groups by actual time for screen work in a day; Group 1, 60 workers, lesser than 4 hours a day and group 11, 204 workers, more than 4 hours a day. From July to October 1992 a questionnaire was administered to all the study subjects for the general charateristics and subjective eye symptoms after which the opthalmologic tests such as visual acuity, spherical equivalent, lacrimal function, ocular pressure, slit lamp test, fundoscopy were conducted by one opthalmologist. The proportion of workers whose present visual acuity was decreased more than 0. 15 in comparison with that on the pre-employment health examination by Han's test chart was 20.6% in Group Ii, 15.0% in Group I and 14.9% in non-screen workers. However, the differences in proportion were not statistically significant. The proportion of workers with decreased visual acuity was not associated with the age, working duration, use of magnifying glass and type of shift work (independent variables) in all of the three groups. However, screen workers working under poor illumination had a higher proportion of persons with decreased visual acuity than those working under adequate illumination (P<0.05). The proportion of workers whose near vision was decreased was 27.5% in Group II, 18.3% in Group I, and 28.4% in non-screen workers and these differences in proportion were not statistically significant. Changes of near vision were not associated with 4 independent variables in all of the three groups. Six out of sever-subjective eye symptoms except tearing were more common in Group I than in non-screen workers and more common in Group II than in Group I (P<0.01). Mean of the total scores for seven subjective symptoms of each worker (2 points for always, 1 point for sometimes, 0 point for never) was not significantly different between workers with decreased visual acuity and workers with no vision change. However, mean of the total scores for Group II was higher than those for the Group I and non-screen workers (P < 0. 01). Total eye symptom scores were significantly correlated with the grade of screen work, use of magnifying glass, and type of shift work. There was no independent variable which was correlated with the difference in visual acuity between the pre-employment health examination and the present state, the difference between far and near visions, lacrimal function, ocular pressure, and spherical equivalent. Multiple linear regression analysis for the subjective eye symptom scores revealed a positive linear relationship with actual time for screen work and shift work(P<0.01). In this study it was not observed that the VDT work decreased visual acuity but it induces subjective eye symptoms such as eye fatigue, blurred vision, ocular discomfort, etc. Maintenance of adequate illumination in the, work place and control of excessive VDT work are recommended to prevent such eye symptoms.

Comparison of Subjective Symptoms of Workers in Rapidly and Weekly Rotating Shift Systems / 예방의학회지

Some circadian rhythms can become disorganized due to rotating shift work. This lack of organization, termed desynchronization, can produce a group of symptoms such as insomnia, GI disturbance and fatigue among many rotating shift workers. The magnitude of these symptoms are influenced by personal and environmental factors and the patterns of shift work. This study was carried out to investigate the subjective symptoms related to rotational schedules of shift work after personal and environmental factors adjusted. 182 male workers in rapidly rotating shift system and 86 male workers in weekly rotating shift system were conducted the questionnaire on personal factors and subjective sleep, GI and fatigue symptoms. Major findings obtained from this study are as follows: 1. The symptoms of 'feeling tired at work' and 'being irritable' were more frequent in weekly rotating shift workers(P<0.05), and the mean of symptom score was significantly higher in weekly rotating shift workers(P<0.01). 2. According to 6 hours of sleeping which is a definite elevation point of fatigue, there was not a significant difference between two groups in sleeping hours. Among workers in rapidly rotating shift system, the mean of symptom score was significantly higher in workers of less than 6 hours of sleeping(P<0.05), but it was not different among weekly rotating shift workers. 3. The symptoms of GI disturbance were more frequent in weekly rotating shift workers but statistically mot significant. 4. The positive rate of mental and physical fatigue symptoms were significantly higher in weekly rotating shift workers(P<0.01) and mental and physical fatigue symptoms were more frequent in them(P<0.01). 5. After the effect of the factors that were significantly different between two groups by X2-test were controlled, the mean score of sleep disturbance was significantly higher in weekly rotating shift workers(P<0.01) and mental physical fatigue symptoms were more frequent in them(P<0.01). Based on these study results, subjective symptoms were more common in the weekly rotating shift workers. In future, medical examination and laboratory test will be also administered to evaluate a more accurate health outcomes and the review of current shift schedules will be required.