• 대한방사선치료학회:학술대회논문집
• /
• 1999.05a
• /
• pp.8-9
• /
• 1999

• 대한방사선치료학회:학술대회논문집
• /
• 1999.05a
• /
• pp.11-11
• /
• 1999

• The Journal of Korean Society for Radiation Therapy
• /
• v.10 no.1
• /
• pp.1-5
• /
• 1998

• The Journal of Korean Society for Radiation Therapy
• /
• v.15 no.1
• /
• pp.41-52
• /
• 2003

I. Purpose The dose distribution in normal tissues and target lesions is very important in the treatment planning. To make the uniform dose distribution in target lesions, many methods has been used. Especially in the head and neck, the dose inhomogeneity at the skin surface should be corrected. Conventional methods have a limitation in delivering the enough doses to the planning target volume (PTV) with minimized dose to the parotid gland and spinal cord. In this study, we investigated the feasibility and the practical QA methods of the forward IMRT. II. Material and Methods The treatment plan of the forward IMRT with the partial block technique using the dynamic multi-leaf collimator (dMLC) for the patients with the nasopharyngeal cancer was verified using the dose volume histogram (DVH). The films and pinpoint chamber were used for the accurate dose verification. III. Results As a result of verifying the DVH for the 2-D treatment plan with the forward IMRT, the dose to the both parotid gland and spinal cord were reduced. So the forward IMRT could save the normal tissues and optimize the treatment. Forward IMRT can use the 3-D treatment planning system and easily assure the quality, so it is easily accessible comparing with inverse IMRT IV. Conclusion The forward IMRT could make the uniform dose in the PTV while maintaining under the tolerance dose in the normal tissues comparing with the 2-D treatment.

• Radiation Oncology Journal
• /
• v.20 no.1
• /
• pp.53-61
• /
• 2002

Purpose : To determine the optimal scheme of postoperative chemoradiotherapy in rectal cancer by comparing survival, Patterns of failure, toxicities in early and late radiotherapy groups using a Phase III randomized prospective clinical trial. Materials and Methods : From January 1996 to March 1999, 307 patients with curatively resected AJCC stage II and III rectal cancer were assigned randomly to an 'early (151 patients, arm 1)' or a 'late (156 patients, arm II)' and were administered combined chemotherapy (5-FU $375\;mg/m^2/day$, leucovorin $20\;mg/m^2$, IV bolus daily, for 3 days with RT, 5 days without RT, 8 cycles with 4 weeks interval) and radiation therapy (whole pelvis with 45 Gy/25 fractions/5 weeks). Patients of arm I received radiation therapy from day 1 of the first cycle of chemotherapy and those of arm II from day 57 with a third cycle of chemotherapy. The median follow-up period of living patients was 40 months. Results : Of the 307 patients enrolled, fifty patients did not receive scheduled radiation therapy or chemotherapy. The overall survival rate and disease free survival rate at 5 years were $78.3\%\;and\;68.7\%$ in arm I, and $78.4\%\;and\;67.5\%$ in arm II. The local recurrence rate was $6.6\%\;and\;6.4\%$ (p=0.46) in arms I and II, respectively, no significant difference was observed between the distant metastasis rates of the two arms ($23.8\%\;and\;29.5\%$, p=0.16). During radiation therapy, grade 3 diarrhea or more, by the NCI common toxicity criteria, was observed in $63.0\%\;and\;58.2\%$ of the respective arms (p=N.S.), but most were controlled with supportive care. Hematologic toxicity (leukopenia) greater than RTOG grade 2 was found in only $1.3\%\;and\;2.6\%$ of patients in each respective arm. Conclusion : There was no significant difference in survival, patterns of failure or toxicities between the early and late radiation therapy arms. Postoperative adjuvant chemoradiation was found to be a relatively safe treatment but higher compliance is needed.

• Radiation Oncology Journal
• /
• v.23 no.3
• /
• pp.137-142
• /
• 2005

Purpose: To analyze the outcome of radiation therapy for patients with a metastatic carcinoma of cervical lymph nodes from an unknown primary (MUO), and identify the prognostic factors for these patients. Materials and Methods: Between July 1981 and June 1999, 39 patients with MUO underwent radiation therapy with curative intent. Twelve patients were treated with radiation therapy alone (Group 1), 8 with neoadjuvant chemotherapy followed by radiation therapy (Group 2), and 19 with either an excision or neck dissection and postoperative radiation therapy (Group 3). There were 31 males and 8 females, with a median age of 55 years, ranging from 25 to 77 ears. The median duration of follow-up was 38 months, ranging from 3 to 249 months. Results: The 5-year overall survival rate was $55\%$. According to the treatment modality, the 5-year disease-free survival rates of Groups 1, 2 and 3 were 48, 19 and $75\%$, respectively (p=0.0324). In addition to the treatment modality, the appearance of the primary site was a significant prognostic factor for disease-free survival (p=0.0085). Conclusion: Surgical resection and radiation therapy achieves a superior disease-free survival compared to radiation therapy alone, either with or without chemotherapy Further investigation Is needed to evaluate the role of chemotherapy in the treatment of MUO.

• Radiation Oncology Journal
• /
• v.15 no.3
• /
• pp.251-254
• /
• 1997

Purpose : Simple hysterectomy is not a standard surgery for invasive cervical carcinoma. This study was performed to investigate the efficacy of radiotherapy following simple hysterectomy in the invasive cervical cancer. Materials and Methods : Retrospective analysis was done for 19 patients with invasive cervical carcinoma who were treated with radiotherapy following simple hysterectomy from April 1989 to December 1993 The median a9e of patients was 47 years old. Patients were treated with external beam radiation therapy alone (17) or external beam radiation therapy plus intra vaginal ovoid irradiation (2). The median follow up period was 46 months. Results : The 4 year overall survival rate was $75\%$. The 4 rear local control rate was $89\%$. Two patients had recurred at the locoregional and distant sites, and another two patients at distant sites. Conclusion : We confirmed that radiotherapy is the adequate treatment modality for patients with invasive cervical cancer who underwent simple hysterectomy.

• The Journal of the Korea Contents Association
• /
• v.13 no.12
• /
• pp.869-879
• /
• 2013

Modern medicine has not yet conquered behavior therapy for cancer radiation treatment, which is one of the professional groups involved in the justification of the act and reasonable human resources was analyzed. Radiation Oncology(Therapeutic Radiology) installed the role of the medical physicist in the current law, the act must have been within the limits given licenses, but the legitimacy of the act which can be given the current laws and regulations are not clear. Thus, certification and testing outside the medical physicist's research institutions, including the measures to be reflected in national legislation sought. Medical physicists, with the inherent illegality act because one of the areas to precluding the illegality of the content-based "medical law" and "Nuclear Safety Law", "medical technology in the field of radiation safety standards on management" was based on the interpretation. In conclusion, "medical law" and "in the field of medical technology on the management of radiation safety standards" that are consistent with the recognition of qualifications, increased activity in the radiation therapy and radiation safety management must deal with this will be feasible.

• Radiation Oncology Journal
• /
• v.17 no.1
• /
• pp.43-51
• /
• 1999

Purpose : To discuss the technical aspect of interstitial brachytherapy including method of implant, insertion time of radioactive source, total radiation dose, and complication, we reviewed patients who had diagnoses of soft tissue sarcoma and were treated by conservative surgery, interstitial implant and external beam radiation therapy Materials and Methods : Between May 1995 and Dec. 1997, ten patients with primary or recurrent soft tissue sarcoma underwent surgical resection (wide margin excision) and received radiotherapy including interstitial brachytherapy. Catheters were placed with regular intervals of 1 ~l.5 cm immediately after tumor removal and covering the critical structures, such as neurovascular bundle or bone, with gelform, muscle, or tissue expander in the cases where the tumors were close to those structures. Brachytherapy consisted of high dose rate, iridium-192 implant which delivered 12~15 Gy to 1 cm distance from the center of source axis with 2~2.5 Gy/fraction, twice a day, starting on 6th day after the surgery, Within one month after the surgery, total dose of 50~55 Gy was delivered to the tumor bed with wide margin by the external beam radiotherapy. Results : All patients completed planned interstitial brachytherapy without acute side effects directly related with catheter implantation such as infection or bleeding. With median follow up duration of 25 months (range 12~41 months), no local recurrences were observed. And there was no severe form of chronic complication (RTOGIEORTC grade 3 or 4). Conclusion : The high dose rate interstitial brachytherapy is easy and safe way to minimize the radiation dose delivered to the adjacent normal tissue and to decrease radiation induced chronic morbidity such as fibrosis by reducing the total dose of external radiotherapy in the management of soft tissue sarcoma with conservative surgery.

• Radiation Oncology Journal
• /
• v.20 no.3
• /
• pp.206-214
• /
• 2002

Purpose : The aim of this study was to assess the effectiveness, survival rate and complications of radiation therapy and chemoradiation treatment in hypopharyngeal cancer. Methods and Materials : From January 1984 to December 1999, 56 patients who had hypopharyngeal carcinoma treated with curative radiation therapy were retrospectively studied. Twenty four patients $(42.9\%)$ were treated with radiation therapy alone (Group I) and $32\;(57.1\%)$ treated with a combination of chemotherapy and radiation (Group II). Total radiation dose ranged from 40.5 to 83. 5 Gy (median 67.9 Gy). Radiotherapy was given with conventional technique in 9 patients $(16.4\%)$, with hyperfractionation I ($1.15\~1.2$ Gy/fr., BID) in 26 $(47.2\%)$, hyperfractionation II (1.35 Gy/fr., BID) in 18 $(32.7\%)$, and accelerated fractionation (1.6 Gy/fr., BID) in 2 $(3.6\%)$. In chemotherapy, 5-FU ($1,000\;mg/m^2$ daily for 5 consecutive days) and cisplatin ($100\;mg/m^2$ on day 1) were administered in a cycle of 3 weeks interval, and a total of 1 to 3 cycles (average 2..3 cycles) were given prior to radiation therapy. Follow up duration was $1\~195$ months (median 28 months). Results : Overall 2 and 5 year survival rates were $40.6\%\;and\;27.6\%;\;50.0\%\;and\;30.0\%$ in Group I, and $36.4\%\;and\;26.3\%$ in Group II, respectively. Complete local control rates in Group I and II were $70.0\%\;and\;67.7\%$, respectively. The response to radiotherapy and nodal stage were statistically significant prognostic factors. The complication rate was increased in Group II and was decreased in hyperfractionation. Conclusion : The response to radiotherapy and nodal stage were valid factors to indicate the degree of control over the hypopharyngeal cancer. The induction cisplatin, 5-Fu chemotherapy was not valid in terms of local control rate and survival rate, but did contribute to an increased complication rate. The use of hyperfractionation was valid to reduce the late radiation complications.