The Results of Intraoperative Radiotherapy for Stomach Cancer / 대한방사선종양학회지

PURPOSE: We retrospectively analyzed the long-term results of radical surgery and intraoperative radiation therapy (IORT) in patients with stomach cancer. MATERIALS AND METHODS: From 1988 to 1994, 51 patients were treated with curative surgery and IORT. Postoperative external beam radiotherapy (EBRT) was administered to 30 patients, while adjuvant chemotherapy was administered to 35 patients. A dose of 15 Gy was irradiated with a 9 MeV electron beam as the IORT and a median dose of EBRT was 43.2 Gy (range, 7.2 to 45 Gy). The follow-up period ranged from 1~254 months, with a median follow-up period of 64 months. RESULTS: The median age of all the patients was 58 years (range, 30 to 71 years). The distribution of pathologic stage (American Joint Committee on Cancer [AJCC] 2002 tumor-note-metastasis [TNM]) was as follows: 13 stage I (25.5%), 10 stage II (19.6%), 25 stage III (49.0%), and 3 stage IV (5.9%). Distant metastases occurred in 11 patients (10 in the peritoneum and 1 in bone), including one patient with concurrent local recurrence (anastomosis site). The 5-year locoregional control, disease free survival and overall survival rates were 94.7%, 66.5%, and 51.7%, respectively. For the multivariate analysis, age, TNM stage, and EBRT were significant prognostic factors for overall survival, and only TNM stage for disease free survival. CONCLUSION: We could have achieved a high loco-regional control rate in patients with locally advanced stomach cancer by adding IORT to radical surgery. However, the benefit of IORT on survival remains to be elucidated.

Intraoperative Radiotherapy for Locally Advanced Rectal Cancer

PURPOSE: Although intraoperative radiotherapy (IORT) is known to be a method that can reduce local recurrence in locally advanced colorectal cancer, it is not widely used. The aim of this study was to report our experience with IORT for locally advanced rectal cancer. METHODS: From 1991 to 1994, nine patients with locally advanced rectal cancer received IORT. External beam radiotherapy was given postoperatively in five patients and preoperatively in three. Seven patients received chemotherapy. IORT was done with 6-MeV or 9-MeV electrons, and 12 Gy was irradiated at the tumor bed. The median follow-up period was 84 months (range, 15 to 208 months). RESULTS: The median age of patients was 51 years (range, 42 to 73 years). All patients had advanced clinical T-stage (cT3/4) cancer. The overall and the disease-free survival rates were 66.7% and 66.7% at 5 years, respectively. One patient developed a local recurrence near the anastomosis site, which was out of the IORT field. Four patients died before the last follow-up; three from distant metastasis and one from secondary primary cancer. Adverse effects related to IORT did not occur. CONCLUSION: Although the number of patients was small in this study, IORT is thought to be safe and effective in reducing local recurrence in locally advanced rectal cancer. However, the role of IORT should be refined in the era of preoperative radio-chemotherapy followed by total mesorectal excision.

A Study of Energy Dependency in Intensity Modulated Radiation Therapy of Lung Cancer / 의학물리

PTV considered for the energy, dose distribution exposed to lung and spinal cord, and the characteristic of DVH (Dose Volume Histogram) were compared and investigated by planning the intensity modulated radiation therapy (IMRT) using the photon energies of 6 MV and 10 MV according to tumor location like as the anterior, middle, and posterior regions of lung, and the mediastinum region in lung cancer patients. Our institution installed the linear accelerator (Varian 21 EX-s, USA) equipped with 120 multileaf collimator for lung cancer patients, which is producing the photon energies of 6 MV and 10 MV, and radiation therapy planning was performed with ECLIPSE system (Varian, SomaVision 6.5, USA), which support inverse treatment planning. The tomographic images of 3 mm slice thickness for lung cancer patients were acquired using planning CT, and acquired tomographic images were sent to the Varis system, and then treatment planning was performed in the ECLIPSE system. The radiation treatment planning of the IMRT was processed from various angles according to the regions of the tumor, and using various beam lines according to the size and location of the tumor. The investigation of the characteristic of dose distributions for the energy of 6 MV and 10 MV according to tumor locations in lung cancer patients resulted that the maximum dose of 10 MV energy was 1.2% less than that of 6 MV energy without depending on the tumor location of lung cancer, and the reduction effects of MU were occurred from 10 to 25 MU. Radiation dose exposed to the lung satisfied the less 30% of V20, however radiation dose in 6 MV energy was from 0.1% to 0.5% less than that in 10 MV energy. Radiation dose exposed to the spinal cord for 6 MV energy was from 0.6% to 2.1% less than that for 6 MV energy.

Incidence and Prognostic Factors of Radiation Pneumonitisin NSCLC Treated with Intensity Modulated Radiation Therapy (IMRT) / 대한방사선종양학회지

PURPOSE: To evaluate the incidence and prognostic factors of treatment-related pneumonitis in non-small-cell lung cancer (NSCLC) patients treated with intensity modulated radiation therapy (IMRT). MATERIALS AND METHODS: One-hundred-five patients with NSCLC treated with IMRT between 1 August 2004 and 30 November 2006 were analyzed retrospectively. The mean age of patients was 62.9 years, and squamous carcinomas were confirmed in 81 patients (77%). Sixty-six patients (62.9%) were classified as stage III, and 59 patients had lesions in the right lung. Twenty-seven patients were treated with a dose of 3,060 cGy preoperatively, and 10 patients were given a dose of 5,040 cGy postoperatively. Sixty-eight patients received a dose of 7,020 cGy for curative intent. Sixty-eight patients were treated with the use of the CORVUS planning system and 37 patients were treated with the use of the ECLIPSE planning system. RESULTS: Of 105 patients, 21 patients (20%) had abnormal radiological findings, but only seven patients (6.7%) required treatment for radiation pneumonitis. Six of the seven patients had other serious lesions, including a bronchioesophageal fistula (one patient), recurrence in the treatment field (two patients), brain metastasis (one patient) and lung-to-lung metastasis (two patients); all of these patients died within 19 months after radiation treatment. Sixteen patients (23.5%) that received planning with the CORVUS system had abnormal lung findings. Five patients (13.5%) had abnormal lung findings with the use of the ECLIPSE planning system. Other prognostic factors such as perioperative radiation therapy, a volume over 10% of the V20 volume in the right lung, were also statistically significant. CONCLUSION: This retrospective analysis suggests that IMRT could be a beneficial treatment modality for the reduction of radiation pneumonitis in NSCLC patients. However, the higher incidence of abnormal radiological findings in perioperative patients treated with relatively lower doses (3,060~5,040 cGy) suggest the need for judicious treatment planning in preoperative or postoperative treatment.

Evaluation of Skin Dose of Intensity Modulated Radiation Therapy in Breast Cancer Patients / 의학물리

In the case of radiotherapy following breast conservation therapy for breast cancer patients, the characteristic of skin dose was investigated in the treatment of intensity modulated radiation therapy (IMRT) for breast cancer patients by comparing and analysing entrance skin dose irradiated during radiotherapy using tangential technique radiotherpy, and IMRT. The calculation dose irradiated to breast skin was compared with TLD measurement dose in treatment planning by performing the two methods of radiotherapy using tangential technique, and IMRT in treatment planning equipment. The skin absorbed dose was measured to pass a nipple by spacing of 1 cm distance from center to edge of body. In the radiotherapy of tangential technique, for the irradiation of 180 cGy to PTV, the calculation dose was ranged from 103.6 cGy to 155.2 cGy, measurement dose was ranged from 107.5 cGy to 156.2 cGy, and skin dose in the center was maximum 1.45 times more irradiated than that in the edge. In the IMRT, for the irradiation of 180 cGy to PTV, the calculation dose was ranged 9.8 cGy at 80.2 cGy, measurement dose was ranged 8.9 cGy at 77.2 cGy, and skin dose in the center was maximum 0.23 times less irradiated than that in the edge. IMRT was more effective for skin radiation risks because radiation dose irradiated to skin in IMRT was much less than that in radiotherapy of tangential field technique.

Effects of Antioxidants on the Gamma-Radiation Damage of the Cultured Vascular Smooth Mucle Cells of Rat Aorta

To study the protective effects of antioxidants on the radiation damages of the cells, vascular smooth muscle cells (VSMC) from thoracic aorta of Sprague-Dawley rats were cultured and irradiated with gamma-ray. Cell viability was measured by direct cell counting and MTT assay, and flow cytometry was performed to measure fractional distributions of the cells. Gamma-ray irradiation inhibited cell proliferations accompanied with decreased G1 phase and increased S- and G2/M phases, and the maximum effects were observed at 1500 or 2000 cGy. Submaximal concentrations of antioxidants, such as allopurinol, vitamin C, N-acetylcycteine (NAC), lipoic acid, dihydrolipoic acid and rebamipide tended to increase the cell viability suppressed by low dose of radiation (500 cGy), and enalapril and vitamin E increased it significantly. Allopurinol, vitamin E, NAC, lipoic acid, captopril and enalapril significantly increased G1 phase. Allopurinol and vitamin E tended to increase c-Myc expression, detected by Western blot, that was reduced by the radiation, and enalapril increased it significantly. The cell viability and c-Myc expression were highly correlated (r=0.97) with each other. These results suggest that antioxidants, especially enalapril and vitamin E, recover the viability of VSMC from gamma-radiation injury, through a mechanism which includes increase of c-Myc protein expression.

Development of Multichannel On-line Thermometry System / 영남의대학술지

BACKGROUND: Measurement of body temperature is an important parameter inpatient management in many clinical condition. Failure to reach minimal acceptable and has necessitated the application of additional therapy. The authors developed a new, simple, accurate thermometry system, which could be used to undertake precise temperature measurement for various clinical conditions. MATERIALS AND METHODS: A new thermometry system using a specially designed temperature detecting and display system was developed. This system contains a temperature detecting sensor(LM 35CZ), which enables multiple serual checking of heat, data collection and processing computer, and 3-dimensional display system. It provides realtime volumetric visualization of temperature of a defined volume and stores and prints the data. RESULTS: With this system, temperature can be measured at multiple interesting sites simultaneously , demonstrated as a 3-dimensional temperature distribution and stored. In well-controlled, systematic experiments a significant correlation has been observed between standard temperature using this system at carious measuring points. CONCLUSION: This thermonetry system is a real-time measurement system, which can demonstrate 3-dimensional heat distribution in experimental phantom and human body and can be used for diagnosing abnormal conditions. In addition, this system reduces the nursing staff work load, providing them more time for long term care to patients.

Sequential Combination Chemotherapy and Radiotherapy of an Isolated Non-Hodgkin's Lymphoma of the Larynx: Report of A Case / 영남의대학술지

No abstract available.

Development of Detachable IORT Table for Colorectal Cancer / 대한치료방사선과학회지

In spite of remarkable improvement of surgical skills and anesthesia, local failure still occurred in 36-45% of locally advanced colorectal cancer after curative resection with or without pre-or post-operative irradiation. Intraoperative radiation therapy (IORT) is the ideal modality which respectable lesions are removed surgically and the remaining cancer nests are sterilized by irradiation during a surgical procedure. Therefore, the excellent local control without the damage of the adjacent normal tissues can be achieved. In IORT, judicious set up of the treatment cone on the treatment surface of the patient is required for accurate and homogenous dose distribution within treatment field, especially on the slopping surface of sacrum and pelvic sidewall which are the common sites of the local recurrence in rectal cancer. For this purpose, adequate coordination of gantry rotation and table tilting are essential. Adjusting gantry rotation is not difficult but tilting of the table is impossible inconventional treatment couch. Department of Therapeutic Radiology in Yeungnam University Medical Center developed the IORT table for colorectal cancer which is easy to set up and detach on head-down is about 30 degree which is efficient and easy-to-use, not only for IORT but also for colorectal surgery. So far, authors performed IORT with newly developed treatment table in 2 patients with rectal cancer and we found that this newly developed table could contribute in improving the dose distribution of IORT and surgical procedure for colorectal cancer.

Therapeutic Results of Radiotherapy in Nonsmall Cell Lung Cancers / 영남의대학술지

Total 55 patients with nonsmall cell lung cancer treated with radiation therapy at Department of Therapeutic Radiology, Yeungnam University Hospital, between May-1 1986 and April-30 1993 were retrospectively analyzed by clinical characteristics, failure patterns follow up duration and survival ratio according to prognostic factors. Obtained results were as follows : 1. Male to female ratio was 17.3 2. Sixth and seventh decades were predominant age group. 3. The patients were 8 in stage I-II, 34 in stage IIIA, 13 in stage IIIb, respectively. 4. Forty five patients out of 55 were squamous cell carcinoma. 5. Primary tumor were originated from upper lobe bronchi predominantly. 6. The size of the primary tumor, lymph node involvement and the degree of differentiation were important in evaluation of prognosis. 7. In conclusion, for patients with poor prognostic factors systemic chemotherapy and multidisciplinary approach were recommended for better treatment outcome and improvement of survival.

Radition effect on colony formation of hela.S3(SC) cell line / 영남의대학술지

Since discovery of X-rays, radiotherapy has evolved into one of the most scientific branches of medicine and has established its role as the primary line or the secondary line of attack, after surgery,. in the treatment of malignant cancers. Nowadays its importance is illustrated by the fact that as many as 70 per cent of all pastients with cancer will receive radiation therapy at sometime during their disease process. Biologic effects-of X-rays began to be apparant soon after the discovery by Roentgen in 1895. In clinical radiotherapy, the biologic endpoint of most importance is loss of cellular reproductive ability or clonogenicity. One of the commonest ;nays to assess cell survival is to use an in vitro plating assay. We analyzed radiation effect on colony formation of HaLa. S3(SC) cell line and obtained results are as follows The plating efficiency is 0.464. The shape of cell survival curve is similar to multi-target plus single hit component model. Estimated values of Do, Dq, and extrapolation number are 150 cGy, 80 cGy and 1.7 respectively. We reported these experimental data with review of literature.

Conservative surgery and definitive radiotherapy in early breastr cancer / 영남의대학술지

Local excision and axillary dissection followed by radiation therapy to the breast has been shown to achieve equivalent local control and survival as mastectomy in an prospective randomized trials. We analyzed 28 cases of early breast cancer in order to evaluate the therapeutic effects of conservative f surgery and definitive radiotherapy in the management of early breast cancer as possible alternative of simple mastectomy, retrospectively. Obtained results were as follows 1. Treatment related acute side reactions are more prominant in the case of chemoradiotherapy group than radiotherapy alone group. 2. There were no cases of primary, regional or systemic failures on the last follow up examination. 3. Cosmetic results after treatment were satisfactory in 26 cases out of 28 cases on the last follow up examination. 4. There were no demonstrable differences of tumor control and cosmetic results between the treatment groups. Although, these results suggested that definitive radiotherapy after local excision would be a possible and desirable alternative instead of total mastectomy in the management of early breast cancers, analyzed cases were too small and follow up period was too short to evaluate the therapeutic effect of primary radiotherapy after local excision, exactly.

Stereotactic Radiosurgery for Recurrent Glioblastoma Multiforme using Yeungnam Localization Device :Technical note and Clinical trial / 대한치료방사선과학회지

Authors performed a stereotactic radiosurgery with multiple noncoplanar convergent photon beams of linear accelerator (NELAC-1018 18MeV, NEC) using a specially designed Yeungnam localization device for two patients with recurrent glioblastoma multiforme. One patient had 2cmsized and the other 4cm sized mass on the CT images. After single session of treatment with 15 and 20 Gy, headache was improved in a few days after radiosurgery with no remarkable untoward reactions. Our experience with these two patients were encouraging and we found that our localization device, which is easily adjustable and inexpensive, could be a valuable tool for stereotactic radiosurgery particularly in the treatment of recurrent brain tumor.

Complication of Intraoperative Radiation Therapy (IORT) in Gastric Cancer / 대한치료방사선과학회지

Local control is the important prognostic factor in cancer treatment because local control decrease the relative risk of metastatic spread and increse distant metastasis free survival. IORT is the modality which could increase local control without incressing complication, combined with curative operation. Eventhough we could achieve significant deacreased local failure by IORT and curative resection, it should not be committed as a main treatment modality without proving acceptable complications. Therapeutic Radiology Department of Yeungnam University Medical Center have tried 58 IORT from June 15, 1988, and performed 53 IORT in patients with gastric cancer. No local failure has been reporte? by regular follow up so far. Nine cases(17%) of treatment related complifaiton were reported including intestinal obstrution, hemorrhage, sepsis, and bone marrow depression. These complications could be comparable to Jo's 25.2% (chemotherapy + operation), Kim's 18% (chemotherapy only in inoperable patients), because our treatment regimen is consisted of IORT (1500 cGy), external irradiation(--4500 cGy) and extensive chemotherapy (FAM, 5FU+MMC, BACOP). Our data encouraged us to re-inforce further IORT in stomach cancer treatment.

Pallative effect of radiation therapy in management of symptomatic osseous metastases / 영남의대학술지

Bone metastases represent an important and frequent clinical problem in patients with advanced cancers. Especially, painful bone metastases are common features in these patients. Radiotherapy is an effective tool for palliative aim of painful metastatic osseous lesions. Various treatment results have been previously reported. The present retrospective study was aimed to evaluate the efficacy of palliative irradiation on pain relief, with the goal of selecting appropriate irradiation dose schedule. Radiotherapy consisted of 5 times a week with a various fractional dose between 180 and 400cGy. The response of pain relief and the survival time after completion of radiotherapy are related to total dose and most of the patients have shown a similar response by the end of radiotherapy. The higher dose and the more aggressive multimodality treatment, the better pain control and the longer survival time.

Intraoperative radiation therapy(IORT) in locally advanced gastric and colorectal cancer / 대한암학회지

No abstract available.

Radiation therapy of nasopharyngeal cancers / 영남의대학술지

Radiotherapeutically, nasopharyngeal caner is an important disease in Korea. Because of its blind anatomic location, early detection is relatively uncommon. Clinically, most of cases are locally advanced and nodal involvements are common. Recently better understanding of nature of the disease and improvement of radio – therapy technique permit better treatment result, including locoregional control and survival rate, and minimal normal tissue damages comparing with previously published date. We analyzed 31 patients of pathologically proven and previously untreated naso – pharyngeal carcinoma with different treatment techniques, retrospectively. Minimal and maximal follow up period of the survivor is 6 months and 68 months, respectively. Thirteen patients with squamous cell carcinoma are included in this analysis. The median age is 49 years (range from 20 to 64 years). Twenty two patients are stage III. Eleven patients are treated with radiotherapy alone and 20 are treated with combined modalities treatment. The degree of response after radiotherapy are categorized by 3-classes, i,e. complete response, partial response. In spite of similarities of complete response rate and 1-year survival rate between two different treatment techniques, those patients with undifferentiated carcinoma appear to benefit from the adjuvant chemotherapy. In addition, systemic failure is more suggest that adjuvant therapy in the radiotherapeutic management of nasopharyngeal cancer needs additional research according to histologic types and future extensive clinical trials.

Intraoperative Radiotherapy (IORT) for Locally Advanced Colorectal Cancer / 대한치료방사선과학회지

Colorectal cancer is the second most frequent malignant tumor in the United States and fourth most frequent tumor in Korea. Surgery has been used as a primary treatment modality but reported overall survivals after curative resection were from 20% to 50%. Local recurrence is the most common failure in the treatment of locally advanced colorectal cancer. Once recurrence has developed, surgery has rarely the role and the five year survival of locally advanced rectal cancer is less than 5%, this indicated that significant improvement of local conrol could be achieved. We performed 6 cases of IORT for locally advanced colorectal cancer which is he first experience in Korea. Patient's eligibility, treatment applicator, electron energy, dose distribution on the surface and depth within the treatment field and detailed skills are discussed. We hope that our IORT protocol can reduce local failure and increase the long term survival significantly.

IORT in Gastric Cancer / 대한치료방사선과학회지

Total 28 patients with respectable, locally advanced gastric cancer were entered in our prospective randomized study from June 15, 1988 to Sep. 15, 1990 in Yeungnam University Hospital. This study consisted of curative resection, IORT, external irradiation and combination of chemotherapy. Twenty-four of 28 patients were treated with single dose of 1500 cGy per fraction, 5 days per week was started within 4th weeks postoperative days. Various chemotherapy with or without external irradiation were added for reducing hematogenous and/or peritoneal dissemination and determination of complication of each arm. Duration of follow up was 4~31 months. No serious complication related with radiation were reported compare to resection and chemotherapy only group. Although our follow up period is too short to draw any conclusion, IORT appears to improve local control, hopely further survival. Continuous follow up should be needed for evaluation of real therapeutic gain such as complication vs. improved survival.

A study on dose distribution of small irradiation field in the electron therapy / 영남의대학술지

In electron therapy, low melting point alloy is used for shaping of the field. Electron field shaping material affect the output factor as well as the collimator system. The output factors of electron beams for shaped fields from NELAC-1018 were measured using ionization chamber of Farmer type in water phantom. The output factors of electron beams depend on the incident energy, inherent collimator system and the size of shaped field. Obtained results were followings. 1. In the smaller applicator, output varied extremely according to extent of collimator opening. 2. The higher energy, the output is less varied according to treatment field at small field.