• Journal of Global Scholars of Marketing Science
• /
• v.18 no.2
• /
• pp.189-222
• /
• 2008

This study developed a model to empirically investigate the effects of market orientation and relationship orientation with suppliers on business performance and examine the moderating effects of entrepreneur's characteristics (working tenure) and clinic's location. The data was collected from 200 animal clinics which belong to Korean Animal Hospital Association (KAHA)'s national conference in April, 2007. Descriptive statistic, factor analysis, reliability analysis, and regression analysis were conducted to analyze the data using SPSS/PC+ 12.0. The findings are as follows. First, the market orientation of animal clinics influences significantly both financial and non-financial performance. When the moderating effect of entrepreneur's working tenure is considered, market orientation has significant effect on animal clinic's financial and non-financial performance. However, when the moderating effect of animal clinic's location is considered, market orientation has not significant effect on animal clinic's financial and non-financial performance. Second, animal clinic's relationship orientation with suppliers mostly affects the financial and non-financial performance significantly. When entrepreneur's working tenure in the clinic is longer (above 4 years group), relationship orientation with suppliers significantly affects both financial and non-financial performance. Meanwhile, when the entrepreneur's working tenure in the clinic is shorter (less than 3 years group), relationship orientation with suppliers doesn't affect clinic's financial performance but affect non-financial performance partially. In other words, when entrepreneur's working tenure is shorter (less than 3 years group), market orientation more influences on clinic's financial and non-financial performance while relationship orientation with suppliers does less. It is thought that their relation with suppliers and relationship orientation activities with suppliers are less strongly established and maintained yet. So, they primarily focus on market orientation strategy when entrepreneur's working tenure is shorter. Third, when animal clinics are located in non-metropolitan area, relationship orientation with suppliers significantly affects financial and non-financial performance. However, when animal clinics are located in metropolitan area, it doesn't affect financial and non-financial performance either. It is thought that animal clinics which are located in non-metropolitan area need stronger relationship with suppliers and need support more from them as most of suppliers actively work in metropolitan area not in the non-metropolitan area and animal clinics in metropolitan area can easily get better market information than animal clinics in non-metropolitan area. Lastly, while the effect of the market orientation significantly influences animal clinic's business performance continuously, the effect of the relationship orientation differently influences business performance as it is moderated by entrepreneur's working tenure and animal clinic's location. So, relationship orientation with suppliers can be selectively applied to improve the clinic's financial and no-financial performance. In summary, both of animal clinic's marketing orientation and animal clinic's relationship orientation with suppliers positively influence their business performance. However, entrepreneur's working tenure and animal clinic location moderate the relationship between market orientation and relationship orientation and their business performance differently. This study is quite meaningful to empirically investigate the effects of both of market orientation and relationship orientation with suppliers on business performance and examine the moderating effects of entrepreneur's characteristics (working tenure) and clinic's location. And, as this kind of study has been very few in the context of animal clinic industry, it helps practically understand the effects of market orientation and relationship orientation with suppliers on the financial and non-financial performance in animal clinic industry. Furthermore, as the market conditions in animal clinic industry have been in difficulty for a few years, this study can help improve animal clinic's financial and non-financial business performance together with their suppliers as business partners. Lastly, this study can help find mid-term and long-term cooperation between animal clinics and their suppliers. This study has some limitations. So, care should be taken when generalizing the results of the study. First, our samples were collected from only the animal clinics industry. However, a comparison of the results presented here with those form other marketing contexts (e.g., general hospitals) would be worthwhile. Future comparative research will enhance the generality of our contingency theory cross industry context. Second, this study found that market orientation and relationship orientation affect business performance. However, there may be other antecedents, such as internal market orientation and relationship orientation with customers. Also, this research did not consider other moderators, such as overall market conditions, competitive situations, and power/conflict between suppliers and buyers in the relationship between market and relationship orientation and business performance.

• Journal of Nutrition and Health
• /
• v.8 no.1
• /
• pp.15-37
• /
• 1975

I. Subject of the study A study on the nutritive value and utilization of powdered seaweeds. II. Purpose and Importance of the study A. In Korea the shortage of food will be inevitable by the rapidly growing population. It will be very important study to develop a new food from the seaweeds which were not used hitherto for human consumption. B. The several kinds of seaweeds have been used by man in Korea mainly as side-dishes. However, a properly powdered seaweed will enable itself to be a good supplement or mixture to certain cereal flours. C. By adding the powdered seaweed to any cereals which have long been staple foods in this country the two fold benefits; saving of cereals and change of dietary pattern, will be secured. III. Objects and scope of the study A. Objects of the study The objects will come under four items. 1. To develop a powdered seaweed as a new food from the seaweeds which have been not used for human consumption. 2. To evaluate the nutritional quality of the products the analysis for chemical composition and animal feeding experiment will be conducted. 3. Experimental cocking and accepability test will be conducted for the powdered products to evaluate the value as food stuff. 4. Sanitary test and also economical analysis will be conducted for the powdered products. B. Scope of the study 1. Production of seaweed powders Sargassum fulvellum growing in eastern coast and Sargassum patens C.A. in southern coast were used as the material for the powders. These algae, which have been not used for human consumption, were pulverized through the processes of washing, drying, pulverization, etc. 2. Nutritional experiments a. Chemical composition Proximate components (water, protein, fat, cellulose, sugar, ash, salt), minerals (calcium, phosphorus, iron, iodine), vitamins (A, $B_1,\;B_2$ niacin, C) and amino acids were analyzed for the seaweed powders. b. Animal feeding experiment Weaning 160 rats (80 male and 80 female rats) were used as experimental animals, dividing them into 16 groups, 10 rats each group. Each group was fed for 12 weeks on cereal diet (Wheat flour, rice powder, barley powder, potato powder, corn flour) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. After the feeding the growth, feed efficiency ratio, protain efficiency ratio and ,organs weights were checked and urine analysis, feces analysis and serum analysis were also conducted. 3. Experimental cooking and acceptability test a. Several basic studies were conducted to find the characteristics of the seaweed powder. b. 17 kinds of Korean dishes and 9 kinds of foreign dishes were prepared with cereal flours (wheat, rice, barley, potato, corn) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. c. Acceptability test for the dishes was conducted according to plank's Form. 4. Sanitary test The heavy metals (Cd, Pb, As, Hg) in the seaweed powders were determined. 5. Economical analysis The retail price of the seaweed powder was compared with those of other cereals in the market. And also economical analysis was made from the nutritional point of view, calculating the body weight gained in grams per unit price of each feeding diet. IV. Results of the study and the suggestion for application A. Chemical composition 1. There is no any big difference in proximate components between powders of Sargassum fulvellum in eastern coast and Sargassum patens C.A. in southern coast. Seasonal difference is also not significant. Higher levels of protein, cellulose, ash and salt were found in the powders compared with common cereal foods. 2. The levels of calcium (Ca) and iron (Fe) in the powders were significantly higher than common cereal foods and also rich in iodine (I). Existence of vitamin A and vitamin C in the Powders is different point from cereal foods. Vitamin $B_1\;and\;B_2$ are also relatively rich in the powders.'Vitamin A in ·Sargassum fulvellum is high and the levels of some minerals and vitamins are seemed4 to be some influenced by seasons. 3. In the amino acid composition methionine, isoleucine, Iysine and valine are limiting amino acids. The protein qualities of Sargassum fulvellum and Sargassum patens C.A. are seemed to be .almost same and generally ·good. Seasonal difference in amino acid composition was found. B. Animal feeding experiment 1. The best growth was found at.10% supplemental level of the seaweed Powder and lower growth rate was shown at 30% level. 2. It was shown that 15% supplemental level of the Seaweed powder seems to fulfil, to some extent the mineral requirement of the animals. 3. No any changes were found in organs development except that, in kidney, there found decreasing in weight by increasing the supplemental level of the seaweed powder. 4. There is no any significant changes in nitrogen retention, serum cholesterol, serum calcium and urinary calcium in each supplemental level of the seaweed powder. 5. In animal feeding experiment it was concluded that $5%{\sim}15%$ levels supplementation of the seaweed powder are possible. C. Experimental cooking and acceptability test 1. The seaweed powder showed to be utilized more excellently in foreign cookings than in Korean cookings. Higher supplemental level of seaweed was passible in foreign cookings. 2. Hae-Jo-Kang and Jeon-Byung were more excellent than Song-Pyun, wheat cake, Soo-Je-Bee and wheat noodle. Hae-Je-Kang was excellent in its quality even as high as 5% supplemental level. 3. The higher levels of supplementation were used the more sticky cooking products were obtained. Song-Pyun and wheat cake were palatable and lustrous in 2% supplementation level. 4. In drop cookie the higher levels of supplementation, the more crisp product was obtained, compared with other cookies. 5. Corn cake, thin rice gruel, rice gruel and potato Jeon-Byung were more excellent in their quality than potato Man-Doo and potato noodle. Corn cake, thin rice gruel and rice gruel were excellent even as high as 5% supplementation level. 6. In several cooking Porducts some seaweed-oder was perceived in case of 3% or more levels of supplementation. This may be much diminished by the use of proper condiments. D. Sanitary test It seems that there is no any heavy metals (Cd, Pb, As, Hg) problem in these seaweed Powders in case these Powders are used as supplements to any cereal flours E. Economical analysis The price of the seaweed powder is lower than those of other cereals and that may be more lowered when mass production of the seaweed powder is made in future. The supplement of the seaweed powder to any cereals is also economical with the criterion of animal growth rate. F. It is recommended that these seaweed powders should be developed and used as supplement to any cereal flours or used as other food material. By doing so, both saving of cereals and improvement of individual's nutrition will greatly be achieved. It is also recommended that the feeding experiment for men would be conducted in future.

• Progress in Medical Physics
• /
• v.18 no.2
• /
• pp.81-86
• /
• 2007

The cone-beam CT (CBCT) which is acquired using on-board imager (OBI) attached to a linear accelerator is widely used for the image guided radiation therapy. In this study, the effect of respiratory motion on the quality of CBCT image was evaluated. A phantom system was constructed in order to simulate respiratory motion. One part of the system is composed of a moving plate and a motor driving component which can control the motional cycle and motional range. The other part is solid water phantom containing a small cubic phantom ($2{\times}2{\times}2cm^3$) surrounded by air which simulate a small tumor volume in the lung air cavity CBCT images of the phantom were acquired in 20 different cases and compared with the image in the static status. The 20 different cases are constituted with 4 different motional ranges (0.7 cm, 1.6 cm, 2.4 cm, 3.1 cm) and 5 different motional cycles (2, 3, 4, 5, 6 sec). The difference of CT number in the coronal image was evaluated as a deformation degree of image quality. The relative average pixel intensity values as a compared CT number of static CBCT image were 71.07% at 0.7 cm motional range, 48.88% at 1.6 cm motional range, 30.60% at 2.4 cm motional range, 17.38% at 3.1 cm motional range The tumor phantom sizes which were defined as the length with different CT number compared with air were increased as the increase of motional range (2.1 cm: no motion, 2.66 cm: 0.7 cm motion, 3.06 cm: 1.6 cm motion, 3.62 cm: 2.4 cm motion, 4.04 cm: 3.1 cm motion). This study shows that respiratory motion in the region of inhomogeneous structures can degrade the image quality of CBCT and it must be considered in the process of setup error correction using CBCT images.

• The Journal of Korean Physical Therapy
• /
• v.5 no.1
• /
• pp.25-37
• /
• 1993

This study was conducted to investigate an attitude related to physical therapy students's clinical practice, a questionnaire survey was carried out for 101 third grader(Taegu Junior Health College 66, Andong Junior College 35) from 11th of January to 22th of March. The results are as follow : A. Frequency classified by item 1. Among preconception and anxiety on the clinical practice, a shortage of knowledge$(83.2\%)$ was the highest. 2. Among expectation on the clime practice, the chance to meet patients directly$(94.1\%)$ was the highest. 3. Among anxiety after students experienced clinical practice, a shortage of knowledge$(82.2\%)$ was the highest. 4. Among satisfaction after students experienced clinical practice, after students graduated college, they will maintain physical therapist's life continuously$(71.3\%)$ was the highest. B. The variables that showed statistical difference between general characteristics and variables classified by item are as follow : 1. Between sex and anxiety after students experienced clinical practice, girl-students$(86.7\%)$ showed higher rate than man-students$(61.1\%)$ in, a shortage of knowledge(P<0.01). 2. Between religion and expectation on clinical practice, religionists$(65.1\%)$ showed higher rate than nonreligionists $(44.8\%)$ in the chance to practice love for humanity(P<0.05). 3. Between religion and anxiety after students experienced clinical practice, religionist$(65.1\%)$ showed higher rate than nonreligionist$(56.9\%)$ in not unskillful counsel patients(P<0.01). 4. Between religion and satisfaction after students experienced clinical practice, religionist$(81.4\%)$ showed higher rate than nonreligionists$(63.3\%)$ in pride of major choice(P<0.01). 5. Between hospitalization experience of family and exportation on clinical practice, students who had hospitalization experience of family$(79.7\%)$ were higher rate than unexperienced students's$(62.2\%)$ in the chance to apply knowledge(P<0.05). 6. Between hospitalization experience and satisfaction after students experienced dime practice, students who had hospitalization experience$(68.4\%)$ were higher rate than unexperienced students's$(45.1\%)$ in settlement of anxiety(P<0.05). 1. Between choice motive of physiotherapy(PT) department and expectation on clinical practice, self-will students $(80.5\%)$ showed higher rate than other-will students's $(66.7\%)$ in rejoining participate in treatment(P<0.01). 8. Between choice motive of physiotherapy department and anxiety after students experienced clinical practice, self-will students$(74.0\%)$ showed higher rate than lither-will students's $(58.3\%)$ in the wish PT-job in the future(P<0.05). 9. Between choice motive of physiotherapy department and satisfaction after students experienced clinical practice, self-will students$(75.3\%)$ showed higher rate than other-will students's$(58.3\%)$ in pride on major in physical therapy(P<0.05). It was revealed by this survey that girl-students had higher anxiety than man-students in anxiety after students experiences clinical practice, self-will student had higher satisfaction higher than other-will student in the choice of physiotherapy department.

• Radiation Oncology Journal
• /
• v.15 no.2
• /
• pp.121-128
• /
• 1997

Purpose : To evaluate the effect of postoperative adjuvant radiation therapy and chemotherapy on the survival, pattern of failure and complication for locally advanced rectal carcinoma Materials and Methods : From October 1992 to September 1995, twenty eight patients with rectal carcinoma were treated by postoperative adjuvant radiation therapy and chemotherapy Radiation therapy was delivered with 6MV and 15MV linear accelerator, 180c0y fractions 5 day per week. Total radiation doses were 5040cGy in $B_{2+3}$ and 5580cGy in $C_{2+3}$. Within 4 weeks after radical surgery. 5-FU$(400mg/m^2/day)\;and\;Leucovorin(20mg/m^2/day)$ were administered by intravenous injection for 4 days during the first and fifth week of radiation therapy. The median follow up was 19 months with a range 2 to 47 months. Results : The 2 year overall survival and disease free survival rates were $78.6\%\;and\;70.8\%$, respectively. The 2 year overall survival was $93.0\%\;in\;B_{2+3}$ and $76.2\%\;in\;C_{2+3}$(p=0.11) The 2 year disease free survival was $79.4\%\;in\;B_{2+3}\;and\;69.2\%\;in\;C_{2+3}(p=0.13)$. The overall failure rate was $21.42\%$(6/28) including $10.72\%$(3/28) locoregional recurrence, $3.62\%$(1/28) distant metastasis and $7.12\%$(2/28) locoregional recurrence with distant metastasis. The overall locoregional recurrence rate was $17.92\%$(5/28). The 2 year locoregional recurrence rates were $13.32\%(2/15)\;and\;23.12\%$(3/13) for respectively for $B_{2+3}\;and\;C_{2+3}$ The difference between the locoregional recurrence of $B_{2+3}\;and\;C_{2+3}$ patients was not significant(p=0.07). Complications developed in 13 patients$(46.42\%)$, including 8 dermatitis, 7 loose stool, 6 leukopenia, 4 tenesmus, 2 diarrhea. In Univariate analysis, there was no statistically significant factor except for tumor grade in locoregional recurrence, disease free survival and overall survival rate(p=0.04, 0.05, 0.04). Conclusion : This study sugges1s that postoperative adjuvant radiation therapy and chemotherapy is effective in patients with locally advanced rectal cancer. Therefore these results need to be confirmed with a long term follow-up and larger number of patients with the further clinical trials including prospective controlled studies.

• Radiation Oncology Journal
• /
• v.11 no.1
• /
• pp.149-158
• /
• 1993

This is a retrospective analysis of 135 patients with invasive carcinoma of the uterine cervix treated with curative radiotherapy from March 1983 through October 1989 at the Department of Therapeutic Radiology, Kang-Nam 51. Mary's Hospital. Among them, 78 patients received radiotherapy alone and 42 patients treated with neoadjuvant chemotherapy followed by radiotherapy and 15 patients were lost to follow up. All patients had follow up from 2 to 106 months (median; 62 months). Age of the patients ranged from 32 to 79 years at presentation (median; 59 years). According to FIGO classification, there were 20 ($16.7{\%}$) in stage IB, 19 ($15.8{\%}$) in stage IIA,49 ($40.8{\%}$) in stage IIB, 5 ($4.2{\%}$) in stage IIIA, 13 ($10.8{\%}$,) in stage IIIB,14 ($11.7{\%}$) in stage IVA. The pathological classification showed 96 ($80.0{\%}$) squamous cell carcinomas, 5 ($4.2{\%}$) adenocarcinomas and 19 ($15.8{\%}$) proven by cytology. The overall 5-year survival rates was $50.8{\%}$, and the 5-year survival rates by stage IB, IIA, IIB, IIIA, IIIB, IVA was $47.7{\%},\;70.2{\%},\;64.1{\%},\;40.0{\%},\;23.1{\%},\;14.3{\%}$, respectively. The 5-year survival rates was noted $51.2{\%}$ of radiotherapy alone and $50.4{\%}$of neoadjuvant chemotherapy followed by radiotherapy. The overall failure rate was $18.3{\%}$(22/120) including $11.7{\%}$ (14/120) locoregional failure, $5.8{\%}$ (7/120) distant metastasis and $0.8{\%}$(1/120) locoregional failure with distant metastasis. Treatment failure rates by the stages were $15{\%}$ (3/20) in stage IB. $10.5{\%}$ (2/19) in stage IIA, $10.2{\%}$, (5/49) in stage IIB, $20{\%}$ (1/5) in stage IIIA, $61.5{\%}$(8/13) in stage IIB, and $28.6{\%}$ (4/14) in stage IVA. The overall complication rate was $34.2{\%}$(41/120) including wet desquamation $7.5{\%}$, (9/120), diarrhea $6.7{\%}(8/120), radiation proctitis $5.8{\%}$(7/120) in decreasing order. A multivariate analysis of factors influencing the survival showed patient age (p < 0.0291), FIGO stage (p<0.0001), Karnofsky performance status (p<0.0043), initial hemoglobin level (p<0.0001), and intracavitary radiation (p<0.0004), but, no significancy in histology (p<0.29) and treatment method (p < 0.87).

• Radiation Oncology Journal
• /
• v.14 no.1
• /
• pp.41-52
• /
• 1996

Purpose : This paper reports a dosimetric study of 88 patients treated with a combination of external radiotherapy and high dose rate ICR for FIGO stage IIB carcinoma of the cervix. The purpose is to investigate the correlation between the radiation doses to the rectum, external radiation dose to the whole pelvis, ICR reference volume, TDF BED and the incidence of late rectal complications, retrospectively. Materials and Methods : From November 1989 through December 1992, 88 patients with stage IIB cervical carcinoma received radical radiotherapy at Department of Radiation Oncology in Yonsei University Hospital. Radiotherapy consisted of 44-54 Gy(median 49 Gy) external beam irradiation plus high dose rate intracavitary brachytherapy with 5 Gy per fraction twice a week to a total dose of 30 Gy on point A. The maximum dose to the rectum by contrast(r, R) and reference rectal dose by ICRU 38(dr, DR) were calculated. The ICR reference volume was calculated by Gamma Dot 3.11 HDR planning system, retrospectively The time-dose factor(TDF) and the biologically effective dose (BED) were calculated. Results : Twenty seven($30.7\%$) of the 88 patients developed late rectal complications:12 patients($13.6\%$) for grade 1, 12 patients($13.6\%$) for grade 2 and 3 patients($3.4\%$) for grade 3. We found a significant correlation between the external whole pelvis irradiation dose and grade 2, 3 rectal complication. The mean dose to the whole pelvis for the group of patients with grade 2, 3 complication was Higher, $4093.3\pm453.1$ cGy, than that for the patients without complication, $3873.8\pm415.6$ (0.05$7163.0\pm838.5$ cGy, than that for the Patients without rectal complication, $0772.7\pm884.0$ (p<0.05). There was no correlation of the rate of grade 2, 3 rectal complication with the iCR rectal doses(r, dr), ICR reference volume, TDF and BED. Conclusion : This investigation has revealed a significant correlation between the dose calculated at the rectal dose by ICRU 38(DR) or the most anterior rectal dose by contrast(R) dose to the whole pelvis and the incidence of grade 2, 3 late rectal complications in patients with stage IIB cervical cancer undergoing external beam radiotherapy and HOR ICR. Thus these rectal reference points doses and whole pelvis dose appear to be useful Prognostic indicators of late rectal complication in high dose rate ICR treatment in cervical carcinoma.

• Radiation Oncology Journal
• /
• v.14 no.1
• /
• pp.1-8
• /
• 1996

Purpose: We tried to evaluate the role of conventional radiotherapy alone or with neoadjuvant chemotherapy in oropharyngeal cancer in terms of survival rates and to identify prognostic factors affecting survival by retrospective analysis. Materials and Methods: Forty seven patients of oropharyngeal cancer were treated by conventional radiotherapy in our hospital from Nov. 1985 to APr. 1993. Of these, twenty six patients were treated by conventional radio-therapy alone, and 21 patients with neoadjuvant chemotherapy of mostly two or more cycles of cisplatin and pepleomycin. The Patient characteristics of radiotherapy alone group and neoadjuvant chemotherapy group were not different generally. Radiotherapy was performed by 6MV-LINAC and the total radiation doses of Primary tumors were 54.0-79.2 Gy and cervical lymph nodes were 55.8-90.0 Gy with a fraction size of 1.8 or 2.0 Gy per day. The range of follow-up periods was 3-102 months and median was 20 months. The range of a9e was 33-79 years old and median was 58 years old. Results : Overall 3-year actuarial survival rate (3YSR) of all patients was $39\%$. The 3YSRS of stage I (n=5), II (n=11), III (n=12) and IV (n=19) were 60, 55, 33 and $32\%$, respectively The 3YSRS of Tl+2, T3+4 and No, N+ were 55, $18\%$ (p=0.005) and 43, $36\%$ (p>0.1), respectively. There was no difference in 3YSRS between radiotherapy alone group and neoadjuvant chemotherapy group (38 vs $43\%$, p>0.1). According to the original site of primary tumor, the 3YSRS of tonsil (n=32), base of tongue (n=8), soft palate or uvula (n=6) and pharyngeal wall (n=1) were 36 38, 67 and $0\%$, respectively The Patients of soft palate or uvular cancer had longer survival than other primaries but the difference was not significant statistically (p>0.1). Of 32 patients of tonsillar cancer, 22 Patients who had primary extension to adjacent tissue showed inferior survival rate to the ones who had not Primary extension, but the difference was marginally significant statistically (24 vs $60\%$, p=0.08). On Cox multivariate analysis in entire patients with variables of age, T stage, N stage, total duration of radiotherapy, the site of primary tumor and the use of neoadjuvant chemotherapy, only T stage was a significant Prognostic factor affecting 3YSR. Conclusion : The difference of 3YASRS of conventional radiotherapy alone group and neoadjuvant chemotherapy group was not significant statistically. These treatments could be effective in oropharyngeal cancer of early stage, especially such as soft palate, uvular or tonsillar cancer which did not extend to adjacent tissue. But in order to improve the survival of patients of most advanced oropharyngeal cancer, other altered fractionated radiotherapy such as hyperfractionation rather than conventional fractionation or multi-modal approach combining radiotherapy and accessible surgery or concurrent chemotherapy might be beneficial.

• Radiation Oncology Journal
• /
• v.18 no.1
• /
• pp.1-10
• /
• 2000

Purpose : Although using the high energy Photon beam with conventional Parallel-opposed beams radiotherapy for nasopharyngeal carcinoma, radiation-induced xerostomia is a troublesome problem for patients. We conducted this study to explore a new parotid gland sparing technique in 3-D conformal radiotherapy (3-D CRT) in an effort to prevent the radiation-induced xerostomia. Materials and Methods : We peformed three different planning for four clinically node-negative nasopharyngeal cancer patients with different location of tumor(intracranial extension, nasal cavity extension, oropharyngeal extension, parapharyngeal extension), and intercompared the plans. Total prescription dose was 70.2 Gy to the isocenter. For plan-A, 2-D parallel opposing fields, a conventional radiotherapy technique, were employed. For plan-B, 2-D parallel opposing fields were used up until 54 Gy and afterwards 3-D non-coplanar beams were used. For plan-C, the new technique, 54 Gy was delivered by 3-D conformal 3-port beams (AP and both lateral ports with wedge compensator; shielding both superficial lobes of parotid glands at the AP beam using BEV) from the beginning of the treatment and early spinal cord block (at 36 Gy) was peformed. And bilateral posterior necks were treated with electron after 36 Gy. After 54 Gy, non-coplanar beams were used for cone-down plan. We intercompared dose statistics (Dmax, Dmin, Dmean, D95, DO5, V95, VOS, Volume receiving 46 Gy) and dose volume histograms (DVH) of tumor and normal tissues and NTCP values of parotid glands for the above three plans. Results : For all patients, the new technique (plan-C) was comparable or superior to the other plans in target volume isodose distribution and dose statistics and it has more homogenous target volume coverage. The new technique was most superior to the other plans in parotid glands sparing (volume receiving 46 Gy: 100, 98, 69$\%$ for each plan-A, B and C). And it showed the lowest NTCP value of parotid glands in all patients (range of NTCP; 96$\~$100$\%$, 79$\~$99$\%$, 51$\~$72$\%$ for each plan-A, B and C). Conclusion : We conclude that the new technique employing 3-D conformal radiotherapy at the beginning of radiotherapy and cone down using non-coplanar beams with early spinal cord block is highly recommended to spare parotid glands for node-negative nasopharygeal cancer patients.

• Radiation Oncology Journal
• /
• v.17 no.2
• /
• pp.91-99
• /
• 1999

Propose : This study was performed to find out the prognostic factors affecting local control, survival and disease free survival rate in nasopharyngeal carcinomas treated with chemotherapy and radiation therapy. Materials and Methods : We analysed 47 patients of nasopharyngeal carcinomas, histologically confirmed and treated at Chonnam University Hospital between July 1986 and June 1996, retrospectively. Range of patients' age were from 16 to 80 years (median; 52 years). Thirty three (70$\%$) patients was male. Histological types were composed of 3 (6$\%$) keratinizing, 30 (64$\%$) nonkeratinizing squamous cell carcinoma and 13 (28$\%$) undifferentiated carcinoma. Histoiogicai type was not known in 1 patient (2$\%$). We restaged according to the staging system of 1997 American Joint Committee on Cancer Forty seven patients were recorded as follows: 71: 11 (23$\%$), T2a; 6 (13$\%$), T2b; 9 (19$\%$), 73; 7 (15$\%$), 74: 14 (30$\%$), and NO; 7 (15$\%$), Nl: 14 (30$\%$), N2; 21 (45%), N3: 5 (10%). Clinical staging was grouped as follows: Stage 1; 2 (4$\%$), IIA: 2 (4$\%$), IIB; 10 (21$\%$), III; 14 (30$\%$), IVA; 14 (30$\%$) and IVB; 5 (11$\%$). Radiation therapy was done using 6 MV and 10 MV X- ray of linear accelerator. Electron beam was used for the Iymph nodes of posterior neck after 4500 cGy. The range of total radiation dose delivered to the primary tumor was from 6120 to 7920 cGy (median; 7020 cGy). Neoadjuvant chemotherapy was performed with cisplatin +5-fluorouracil (25 patients) or cisplatin+pepleomycin (17 patients) with one to three cycles. Five patients did not received chemotherapy. Local control rate, survival and disease free suwival rate were calculated by Kaplan-Meier method. Generalized Wilcoxon test was used to evaluate the difference of survival rates between groups. multivariate analysis using Cox proportional hazard model was done for finding prognostic factors. Results: Local control rate was 81$\%$ in 5 year. Five year survival rate was 60$\%$ (median survival; 100 months). We included age, sex, cranial nerve deflicit, histologic type, stage group, chemotherapy, elapsed days between chemotherapy and radiotherapy, total radiation dose, period of radiotherapy as potential prognostic factors in multivariate analysis. As a result, cranial none deficit (P=0.004) had statistical significance in local control rate. Stage group and total radiation dose were significant prognostic factors in survival (P=0.000, P=0.012), and in disease free survival rates (P=0.003, P=0.008), respectively. Common complications were xerostomia, tooth and ear problems. Hypothyroidism was developed in 2 patients. Conclusion : In our study, cranial none deficit was a significant prognostic factor in local control rate, and stage group and total radiation dose were significant factors in both survival and disease free survival of nasopharyngeal carcinoma. We have concluded that chemotherapy and radiotherapy used in our patients were effective without any serious complication.