The Prognostic Impact of the Number of Metastatic Lymph Nodes and a New Prognostic Scoring System for Recurrence in Early-Stage Cervical Cancer with High Risk Factors: A Multicenter Cohort Study (KROG 15-04) / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We aimed to assess prognostic value of metastatic pelvic lymph node (mPLN) in early-stage cervical cancer treated with radical surgery followed by postoperative chemoradiotherapy. Also, we sought to define a high-risk group using prognosticators for recurrence. MATERIALS AND METHODS: A multicenter retrospective study was conducted using the data from 13 Korean institutions from 2000 to 2010. A total of 249 IB-IIA patients with high-risk factors were included. We evaluated distant metastasis-free survival (DMFS) and disease-free survival (DFS) in relation to clinicopathologic factors including pNstage, number of mPLN, lymph node (LN)ratio (number of positive LN/number of harvested LN), and log odds of mPLNs (log(number of positive LN+0.5/number of negative LN+0.5)). RESULTS: In univariate analysis, histology (squamous cell carcinoma [SqCC] vs. others), lymphovascular invasion (LVI), number of mPLNs (≤ 3 vs. > 3), LN ratio (≤ 17% vs. > 17%), and log odds of mPLNs (≤ -0.58 vs. > -0.58) were significant prognosticators for DMFS and DFS. Resection margin involvement only affected DFS. No significant survival difference was observed between pN0 patients and patients with 1-3 mPLNs. Multivariate analysis revealed that mPLN > 3, LVI, and non-SqCC were unfavorable index for both DMFS (p 3 in early-stage cervical cancer affects DMFS and DFS. A scoring system using mPLNs > 3, LVI, and non-SqCC could stratify risk groups of recurrence in surgically resected early-stage cervix cancer with high-risk factors.

Adjuvant Treatment after Surgery in Stage IIIA Endometrial Adenocarcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We evaluated the role of adjuvant therapy in stage IIIA endometrioid adenocarcinoma patients who underwent surgery followed by radiotherapy (RT) alone or chemoradiotherapy (CTRT) according to risk group. MATERIALS AND METHODS: A multicenter retrospective study was conducted including patients with surgical stage IIIA endometrial cancertreated by radical surgery and adjuvant RT or CTRT. Disease-free survival (DFS) and overall survival (OS) were analyzed. RESULTS: Ninety-three patients with stage IIIA disease were identified. Nineteen patients (20.4%) experienced recurrence, mostly distant metastasis (17.2%). Combined CTRT did not affect DFS (74.1% vs. 82.4%, p=0.130) or OS (96.3% vs. 91.9%, p=0.262) in stage IIIA disease compared with RT alone. Patients with age ≥ 60 years, grade G2/3, and lymphovascular space involvement had a significantly worse DFS and those variables were defined as risk factors. The high-risk group showed a significant reduction in 5-year DFS (≥ 2 risk factors) (49.0% vs. 88.0%, p < 0.001) compared with the low-risk group (< 2). Multivariate analysis confirmed that more than one risk factor was the only predictor of worse DFS (hazard ratio, 5.45; 95% confidence interval, 2.12 to 13.98; p < 0.001). Of patients with no risk factors, a subset treated with RT alone showed an excellent 5-year DFS and OS (93.8% and 100%, respectively). CONCLUSION: We identified a low-risk subset of stage IIIA endometrioid adenocarcinoma patients who might be reasonable candidates for adjuvant RT alone. Further randomized studies are needed to determine which subset might benefit from combined CTRT.

Risk Factors for Distant Metastasis as a Primary Site of Treatment Failure in Early-Stage Breast Cancer / 전남의대학술지

The aim of this study was to evaluate the risk factors for distant metastasis (DM) as a primary site of failure in early-stage breast cancer. Data from 294 patients diagnosed with pathologic stage I or II breast cancer between January 2000 and December 2005 were reviewed retrospectively. Median follow-up duration was 81.0 months (range, 18-135 months). The total number of patients with DM without evidence of locoregional recurrence was 20 and the median time between surgery and DM was 29 months (range, 9-79 months). Median survival time was 38 months (range, 22-77 months) after operation. HER-2 positivity (p=0.015), T stage of tumor (p=0.012), and number of involved lymph nodes (p=0.008) were significant predictors of DM in the univariable analysis. Number of involved lymph nodes [p=0.005, hazards ratio (HR): 1.741; 95% confidence interval (CI): 1.178-2.574] and HER-2 positivity (p=0.018, HR: 2.888; 95% CI: 1.201-6.941) had a statistically significant effect on DM-free survival in the multivariable analysis. A cautious evaluation may be helpful when patients with risk factors for DM have symptoms implying the possibility of DM. To reduce DM, applying intensive therapy is needed after curative surgery for patients with high risk for DM.

Risk Factors for Distant Metastasis as a Primary Site of Treatment Failure in Early-Stage Breast Cancer / 전남의대학술지

The aim of this study was to evaluate the risk factors for distant metastasis (DM) as a primary site of failure in early-stage breast cancer. Data from 294 patients diagnosed with pathologic stage I or II breast cancer between January 2000 and December 2005 were reviewed retrospectively. Median follow-up duration was 81.0 months (range, 18-135 months). The total number of patients with DM without evidence of locoregional recurrence was 20 and the median time between surgery and DM was 29 months (range, 9-79 months). Median survival time was 38 months (range, 22-77 months) after operation. HER-2 positivity (p=0.015), T stage of tumor (p=0.012), and number of involved lymph nodes (p=0.008) were significant predictors of DM in the univariable analysis. Number of involved lymph nodes [p=0.005, hazards ratio (HR): 1.741; 95% confidence interval (CI): 1.178-2.574] and HER-2 positivity (p=0.018, HR: 2.888; 95% CI: 1.201-6.941) had a statistically significant effect on DM-free survival in the multivariable analysis. A cautious evaluation may be helpful when patients with risk factors for DM have symptoms implying the possibility of DM. To reduce DM, applying intensive therapy is needed after curative surgery for patients with high risk for DM.

Esophageal tolerance to high-dose stereotactic radiosurgery

PURPOSE: Esophageal tolerance is needed to guide the safe administration of stereotactic radiosurgery (SRS). We evaluated comprehensive dose-volume parameters of acute esophageal toxicity in patients with spinal metastasis treated with SRS. MATERIALS AND METHODS: From May 2008 to May 2011, 30 cases in 27 patients with spinal metastasis received single fraction SRS to targets neighboring esophagus. Endpoints evaluated include length (mm), volume (mL), maximal dose (Gy), and series of dose-volume thresholds from the dose-volume histogram (volume of the organ treated beyond a threshold dose). RESULTS: The median time from the start of irradiation to development of esophageal toxicity was 2 weeks (range, 1 to 12 weeks). Six events of grade 1 esophageal toxicity occurred. No grade 2 or higher events were observed. V15 of external surface of esophagus was found to predict acute esophageal toxicity revealed by multivariate analysis (odds radio = 1.272, p = 0.047). CONCLUSION: In patients with spinal metastasis who received SRS for palliation of symptoms, the threshold dose-volume parameter associated with acute esophageal toxicity was found to be V15 of external surface of esophagus. Restrict V15 to external surface of esophagus as low as possible might be safe and feasible in radiosurgery.

Treatment outcome in patients with triple negative early stage breast cancers compared with other molecular subtypes

PURPOSE: To determine whether triple negative (TN) early stage breast cancers have poorer survival rates compared with other molecular types. MATERIALS AND METHODS: Between August 2000 and July 2006, patients diagnosed with stage I, II early stage breast cancers, in whom all three markers (estrogen receptor, progesterone receptor, and human epidermal growth factor receptor [HER]-2) were available and treated with modified radical mastectomy or breast conserving surgery followed by radiotherapy, were retrospectively reviewed. RESULTS: Of 446 patients, 94 (21.1%) were classified as TN, 57 (12.8%) as HER-2 type, and 295 (66.1%) as luminal. TN was more frequently associated with young patients younger than 35 years old (p = 0.002), higher histologic grade (p 0.05). CONCLUSION: We found that patients with TN early stage breast cancers had no difference in survival rates compared with other molecular subtypes. Prospective study in homogeneous treatment group will need for a prognosis of TN early stage breast cancer.

A comparison of preplan MRI and preplan CT-based prostate volume with intraoperative ultrasound-based prostate volume in real-time permanent brachytherapy

PURPOSE: The present study compared the difference between intraoperative transrectal ultrasound (iTRUS)-based prostate volume and preplan computed tomography (CT), preplan magnetic resonance imaging (MRI)-based prostate volume to estimate the number of seeds needed for appropriate dose coverage in permanent brachytherapy for prostate cancer. MATERIALS AND METHODS: Between March 2007 and March 2011, among 112 patients who underwent permanent brachytherapy with 125I, 60 image scans of 56 patients who underwent preplan CT (pCT) or preplan MRI (pMRI) within 2 months before brachytherapy were retrospectively reviewed. Twenty-four cases among 30 cases with pCT and 26 cases among 30 cases with pMRI received neoadjuvant hormone therapy (NHT). In 34 cases, NHT started after acquisition of preplan image. The median duration of NHT after preplan image acquisition was 17 and 21 days for cases with pCT and pMRI, respectively. The prostate volume calculated by different modalities was compared. And retrospective planning with iTRUS image was performed to estimate the number of 125I seed required to obtain recommended dose distribution according to prostate volume. RESULTS: The mean difference in prostate volume was 9.05 mL between the pCT and iTRUS and 6.84 mL between the pMRI and iTRUS. The prostate volume was roughly overestimated by 1.36 times with pCT and by 1.33 times with pMRI. For 34 cases which received NHT after image acquisition, the prostate volume was roughly overestimated by 1.45 times with pCT and by 1.37 times with pMRI. A statistically significant difference was found between preplan image-based volume and iTRUS-based volume (p < 0.001). The median number of wasted seeds is approximately 13, when the pCT or pMRI volume was accepted without modification to assess the required number of seeds for brachytherapy. CONCLUSION: pCT-based volume and pMRI-based volume tended to overestimate prostate volume in comparison to iTRUS-based volume. To reduce wasted seeds and cost of the brachytherapy, we should take the volume discrepancy into account when we estimate the number of 125I seeds for permanent brachytherapy.

Permanent Brachytherapy of Localized Prostate Cancer: Preliminary Results / 대한방사선종양학회지

PURPOSE: To evaluate the biochemical control rate and the rate of side effects after performing permanent brachytherapy of localized prostate cancer. MATERIALS AND METHODS: 67 patients with localized prostate cancer were treated with brachytherapy between April 2007 and December 2008. Of these, 43 patients who were followed up and did not receive external radiotherapy were evaluated for the change in prostate specific antigen (PSA) level and the occurrence of side effects. In total, 18 patients were classified as low risk, 19 patients as intermediate risk, and 6 patients as high risk. The prescription dose was 145 Gy. RESULTS: A PSA increase greater than 2 ng/mL occurred in 2 patients (4.7%). Radiation Therapy Oncology Group (RTOG) grade 1 and 2 acute urologic complications (UC) occurred in 40 and 3 patients, respectively. Further, 5 patients had RTOG grade 1 acute rectal complication (RC). The numbers of RTOG grade 1, 2, and 3 chronic UC were 1, 4, and 1, respectively. The numbers of RTOG grade 1, 2, and 4 chronic RC were 5, 10, and 3, respectively. The statistically significant risk factors (RF) of acute RC were the minimal dose in the most irradiated 0.1 cc volume (D0.1CC, p=0.041) and absolute volume receiving 150% of the prescribed dose (V150cc, p=0.038) in the entire rectum (ER). The percentage (V100%, p=0.019) and absolute volume (V100cc, p=0.047) in the involved rectum (IR) were also statistically significant. The RF of chronic RC were V100% (p=0.011) in the ER and the D0.1cc (p=0.049), V100cc (p=0.023) in the IR. The number of used seeds were related with acute UC (p=0.028). CONCLUSION: Permanent brachytherpy of localized prostate cancer showed a favorable short term biochemical control rate. As such, selective intermediate and high risk patients can be managed with permanent brachytherapy. The effort to reduce rectal complication is also necessary.

Reduced-intensity Umbilical Cord Blood Transplantation in Adult Acute Myeloid Leukemia: Report of Four Cases / 대한혈액학회지

The outcome after unrelated cord blood transplantation (CBT) is similar to that of matched unrelated bone marrow transplantation in children, and the results of CBT in adult patients has recently shown improvement. In addition, the use of reduced-intensity conditioning regimens for CBT has shown stable engraftment and reduced treatment-related mortality (TRM). From May 2005 to Jan 2006, four adult patients with acute myelogenous leukemia were treated with CBT after reduced-intensity conditioning at our hospital. The mean age of patients was 53.8 yrs, and all patients received 2 HLA antigen mismatched single unit cord blood. The infused mean cell dose was 2.85 x 10(7)/kg for total nucleated cells and 0.72 x 10(5)/kg for CD34+ cells. All patients had engraftment. The mean number of days to WBC and platelet engraftment was D+20.3 and D+60.3, respectively. There was no TRM within 100 days after transplantation. At the last follow up, three of the four patients were alive. One patient transplanted in first complete remisson is alive in remission at day 413, but the other patients transplanted in advanced disease all relapsed. Reduced-intensity CBT is a feasible approach in selected adult patients with acute myeloid leukemia.

A Case of Mantle Cell Lymphoma Treated with Autologous Stem Cell Transplantation and Rituximab / 대한혈액학회지

Mantle cell lymphoma is a subtype of aggressive non-Hodgkin's lymphoma and usually presents in advanced stages. When treated with a regimen such as CHOP, the median survival is about three years. More aggressive front-line therapy with the hyper-CVAD regimen or high-dose therapy with stem cell support has shown encouraging results in several trials. The addition of rituximab to the chemotherapy regimens, or high-dose therapy, increased the response and survival rates in patients with mantle cell lymphoma. We report a case of mantle cell lymphoma that was successfully treated with aggressive front-line treatment strategies. The patient achieved complete remission with initial hyper-CVAD regimen, and was consolidated with autologous stem cell transplantation and subsequent rituximab.

Postoperative Adjuvant Chemoradiotherapy in Rectal Cancer / 대한방사선종양학회지

PURPOSE: To evaluate the role of postoperative adjuvant chemoradiotherapy in rectal cancer, we retrospectively analyzed the treatment outcome of patients with rectal cancer taken curative surgical resection and postoperative adjuvant chemoradiotherapy. MATERIALS AND METHODS: A total 46 patients with AJCC stage II and III carcinoma of rectum were treated with curative surgical resection and postoperative adjuvant chemoradiotherapy. T3 and T4 stage were 38 and 8 patients, respectively. N0, N1, and N2 stage were 12, 16, 18 patients, respectively. Forty patients received bolus infusions of 5-fluorouracil (500 mg/m2/day) with leucovorin (20 mg/m2/day), every 4 weeks interval for 6 cycles. Oral Uracil/Tegafur on a daily basis for 6~12 months was given in 6 patients. Radiotherapy with 45 Gy was delivered to the surgical bed and regional pelvic lymph node area, followed by 5.4~9 Gy boost to the surgical bed. The follow up period ranged from 8 to 75 months with a median 35 months. RESULTS: Treatment failure occurred in 17 patients (37%). Locoregional failure occurred in 4 patients (8.7%) and distant failure in 16 patients (34.8%). There was no local failure only. Five year actuarial overall survival (OS) was 51.5% and relapse free survival (RFS) was 58.7%. The OS and RFS were 100%, 100% in stage N0 patients, 53.7%, 47.6% in N1 patients, and 0%, 41.2% in N2 patients (p=0.012, p=0.009). The RFS was 55%, 78.5%, and 31.2% in upper, middle, and lower rectal cancer patients, respectively (p=0.006). Multivariate analysis showed that N stage (p=0.012) was significant prognostic factor for OS and that N stage (p=0.001) and location of tumor (p=0.006) were for RFS. Bowel complications requiring surgery occurred in 3 patients. CONCLUSION: Postoperative adjuvant chemoradiotherapy was an effective modality for locoregional control of rectal cancer. But further investigations for reducing the distant failure rate are necessary because distant failure rate is still high.

Combined Arthroscopic Gross Total Synovectomy and Radiotherapy for Diffuse Pigmented Villonodular Synovitis of the Knee: A Report of 2 Cases / 대한방사선종양학회지

Pigmented villonodular synovitis (PVNS) is a rare proliferative disease involving synovial membranes. Natural history and etiology of PVNS are not well known. PVNS presents as localized or diffuse tumor like nodular lesion of the synovial lining of the joint and the synovial spaces adjacent to the joints. Though histologically benign, it is a very aggressive lesion, capable of bone destruction and widespread infiltration of surrounding tissues. Standard therapy is surgical resection, but due to the infiltrative growth, the recurrence rate is significantly high. After several relapses surgical treatment of diffuse PVNS becomes difficult and may require amputation of the involved limb. Radiotherapy can provide an effective treatment option for patients with large lesions or lesions which are not suitable for surgery, after incomplete resection to prevent relapses or to avoid amputation. We report 2 cases of diffuse PVNS in the knee joint treated with arthroscopic gross total synovectomy and radiotherapy.

Biological Markers as Predictors of Radiosensitivity in Syngeneic Murine Tumors / 대한방사선종양학회지

PURPOSE: We investigated whether a relationship exists between tumor control dose 50 (TCD50) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD50, TGD, RIA and constitutive expression levels of the genetic products regulating RIA. MATERIALS AND METHODS: Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8~12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD50, TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21(WAF1/CIP1), BAX, Bcl-2, Bcl-x(L), Bcl-x(S), and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD50 or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD50, TGD, RIA. RESULTS: The level of RIA showed a significant positive correlation (R=0.922, p=0.026) with TGD, and showed a trend to correlation (R=-0.848), marginally significant correlation with TCD50 (p=0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21(WAF1/CIP1) and p34 showed a significant correlation either with TCD50 (R=0.893, p=0.041 and R=0.904, p=0.035) or with TGD (R=-0.922, p=0.026 and R=-0.890, p=0.043). The tumors with high constitutive expression levels of p21(WAF1/CIP1) or p34 were less radiosensitive than those with low expression. CONCLUSION: Radiosensitivity may be predicted with the level of RIA in murine tumors. The constitutive expression levels of p21(WAF1/CIP1) or p34 can be used as biological markers which predict the radiosensitivity.

Determination of Quality Factors for Cylindrical Ionization Chambers in kV X-rays: Review of IAEA Dosimetry Protocol and Monte Carlo Calculations and Measurements for N23333 and N30001 Chambers / 의학물리

The quality factors for cylindrical ionization chambers for kV X-rays were determined by Monte Carlo calculation and measurement. In this study, the X-rays of 60~300 kV beam (ISO-4037) installed in KFDA and specified in energy spectra and beam qualities, and the chambers of PTW N23333 and N30001 were investigated. In calculations, the k(u) and k(Q,Q(0)) in IAEA dosimetry protocols were determined from the air kerma and the cavity dose obtained by theoretical and Monte Carlo calculations. It is shown that the N30001 chamber has a flat response of +/-1.7% in 110~300 kV region, while the response range of two chambers were shown to +/-3~4% in 80~250 kV region. From this work we have discussed dosimetry protocol for the kV X-rays and we have found that the estimation of energy dependency is more important to apply dosimetry protocol for kV X-rays.

The National Survey of Breast Cancer Treatment Pattern in Korea (1998): The Use of Breast-Conserving Treatment / 대한방사선종양학회지

PURPOSE: In order to improve the proper use of radiotherapy and breast-conserving treatment (BCT) in the management of breast cancer, current status of breast cancer treatment in Korea was surveyed nationwide and the use of BCT were evaluated. MATERIALS AND METHODS: Patients characteristics and treatment pattern of 1048 breast cancer patients from 27 institutions diagnosed between January, 1998 and June, 1998 were analyzed. The incidence of receiving BCT was analyzed according to the stage, age, geography, type of hospital, and the availability of radiotherapy facility. RESULTS: Radical mastectomy was performed in 64.8% of total patients and 26% of patients received breast- conserving surgery (BCS). The proportions of patients receiving BCT were 47.5% in stage 0, 54.4% in stage I, and 20.3% in stage II. Some of the patients (6.6% of stage I, 10.1% of stage II and 66.7% of stage III) not received radiotherapy after BCS. Only 45% of stage III patients received post-operative radiotherapy after radical mastectomy. The proportion of patients receiving BCT was different according to the geography and availability of radiotherapy facilities. CONCLUSION: Radiotherapy was not fully used in the management of breast cancer, even in the patients received breast-conserving surgery. The proportion of the patients who received BCT was lower than the report of western countries. To improve the application of proper management of breast cancer, every efforts such as a training of physicians, public education, and improving accessibility of radiotherapy facilities should be done. The factors predicting receipt of BCT were accessibility of radiotherapy facility and geography. Also, periodic survey like current research is warranted.

Combined Chemotherapy and Radiotherapy versus Radiotherapy alone in the Management of Localized Angiocentric Lymphoma of the Head and Neck / 대한방사선종양학회지

PURPOSE: To clarify the clinical benefit derived from the combined modality therapy (CMT) consisting of chemotherapy (CT) and involved field radiotherapy (RT) for stage I and II angiocentric lymphomas of the head and neck. MATERIALS AND METHODS: Of 143 patients with angiocentric lymphoma of the head and neck treated at our hospital between 1976 and 1995, 104 patients (RT group) received involved field RT alone with a median dose of 50.4 Gy (range : 20-70 Gy), while 39 patients (CMT group) received a median 3 cycles (range : 1-6 cycles) of CT before involved field RT. The response rate, patterns of failure, complications, and survival data of the RT group were compared with those of the CMT group. RESULTS: Despite a higher response rate, local failure was the most common pattern of failure in patients of both groups. The patterns of failure, including the systemic relapse rate were not influenced by the addition of combination CT. Although both modalities were well tolerated by the majority of patients, aberrant immunologic disorders or medical illnesses, such as a hemophagocytic syndrome, sepsis, intractable hemorrhage, or the evolution of second primary malignancies were more frequently observed in patients of the CMT group. The prognosis of patients in the RT group was relatively poor, with a 5-year overall actuarial survival rate of 38% and disease-free survival rate of 32%, respectively. However, their clinical outcome was not altered by the addition of systemic CT. Achieving complete remission was the most important prognostic factor by univariate and multivariate analyses, but treatment modality was not found to be a prognostic variable influencing survival. Conclusions : Involved field RT alone for angiocentric lymphoma of the head and neck was insufficient to achieve an improved survival rate, but the addition of CT to involved field RT failed to demonstrate any therapeutic advantage over involved field RT alone.

Radiation Effect on NO, NOS and TGF-beta Expressions In Rat Lung / 대한방사선종양학회지

PURPOSE: NOS2 induce NO production and NO activate TGF-beta. The TGF-beta is a inhibitor of NOS2. If this negative feedback mechanism operating in radiation pneumonitis model, NOS2 inhibitor may play a role in TGF-beta suppression. We planned this study to evaluate the expression patterns of NO, NOS2 and TGF-beta in vivo radiation pneumonitis model. MATERIALS AND METHODS: Sixty sprague-Dawley rat were irradiated 5 Gy or 20 Gy. They were sacrificed 3, 7, 14, 28 and 56 days after irradiation. During sacrifice, we performed broncho-alveolar lavage (BAL). The BAL fluids were centrifuged and supernatents were used for measure NO and TGF-beta, and the cells were used for RT-PCR. RESULTS: After 5 Gy of radiation, NO in BAL fluid increased at 28 days in both lung and TGF-beta in left lung at 56 days. NO increased in BAL fluid at 28 days in both lung after irradiation and TGF-beta in right lung at 28-56 days after 20 Gy of radiation. After 5 Gy of radiation, NOS2 expression was increased in right lung at 14 days, in both lung at 28 days and in left lung at 56 days. TGF-beta expression was reduced in both lung at 28 days and increased in left lung at 56 days. CONCLUSIONS: The proposed feedback mechanism of NO, NOS2 and TGF-beta was operated in vivo radiation pneumonitis model. At 56 days, however, NOS2 and TGF-beta expressed concurrently in left lung after 5 Gy and in both lung after 20 Gy of radiation.

Parotid Gland Sparing Radiotherapy Technique Using 3-D Conformal Radiotherapy for Nasopharyngeal Carcinoma / 대한방사선종양학회지

PURPOSE: Although using the high energy photon beam with conventional parallel-opposed beams radio-therapy for nasopharyngeal carcinoma, radiation-induced xerostomia is a troublesome problem for patient. We conducted this study to explore a new parotid gland sparing technique in 3-D conformal radiotherap (3-D CRT) in an effort to prevent the radiation-induced xerostomia. MATERIALS AND METHODS: We performed three different planning for four clinically node-negative naso-phar yngeal cancer patients with different location of tumor(intracranial extension, nasal cavity extension, oropharyngeal extension, parapharyngeal extension), and intercompared the plans. Total prescription dos <. 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 an < 3 afterwards 3-D non-coplanar beams were used. For plan-C, the new technique, 54 Gy was delivered b r 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 performed. And bilateral posterio r necks were treated with electron after 36 Gy. After 54 Gy, non-coplanar beams were used for cone-down plan. We intercompared dose statistic; Dmax, Dmin, Dmean, D95, D05, V95, V05, 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, 9 B, 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.

Measurements of Setup Error and Physiological Movement of Liver by Using Electronic Portal Imaging Device in Patients with Hepatocellular Carcinoma / 대한방사선종양학회지

PURPOSE: The goal of this study was to improve the accuracy of three-dimensional conformal radio therapy (3-D CRT) by measuring the treatment setup error and physiological movement of liver based on the analysis of images which were obtained by electronic portal imaging device (EPID). MATERIALS AND METHODS: For 10 patients with hepatocellular carcinoma, 4-7 portal images were obtained by using EPID during the radiotherapy from each patient daily. We analyzed the setup error and physiological movement of liver based on the verification data. We also determined the safety margin of the tumor in 3-D CRT through the analysis of physiological movement. RESULTS: The setup errors were measured as 3 mm with standard deviation 1.70 mm in x direction and 3.7 mm with standard deviation 1.88 mm in y direction respectively. Hence, deviation were smaller than 5 mm from the center of each axis. The measured range of liver movement due to the physiological motion was 8.63 mm on the average. Considering the motion of liver and setup error, the safety margin of tumor was at least 15 mm. CONCLUSION: EPID is a very useful device for the determination of the optimal margin of the tumor, and thus enhance the accuracy and stability of the 3-D CRT in patients with hepatocellular carcinoma.

Radiation Therapy of Intracranial Germinomas: Optimum Radiation Dose and Treatment Volume / 대한방사선종양학회지

PURPOSE: To evaluate the possibility of decreasing the radiation dose and to determine optimum treatment volume in intracranial germinomas. MATERIALS AND METHODS: Forty five patients with pathologically-verified or presumed germinomas by a radiosensitivity test who had been treated with radiotherapy (RT) alone between 1971 and 1992 were retrospectively analyzed. The average age was 17.2 years with 68.9% of the patients being between the ages of 10-20. The male and female ratio was 2.2:1. The locations of the primary tumors were at the pineal regions in 14 patients; the suprasellar regions in 12 patients; and multiple sites in 12 patients. Treatment volumes varied from a small local field (10) to the whole brain (7) or entire neuroaxis irradiation(28). All the cases after 1982 received craniospinal irradiation (CSI). Radiation doses were 41-59 Gy (median 48.5 Gy) to the primary tumor site and 19.5-36 Gy (median 24 Gy) to the neuroaxis. The median follow-up period was 82 months with a range of 2-260 months. RESULTS: All the patients showed complete response after RT. Four patients sufferred from recurrence 14, 65, 76, and 170 months after RT, respectively, and two patients died with intercurrent disease. One of four recurrent cases was salvaged by re-irradiation. Therefore, a 5 and 10 year overall survival was 95.3 % and 84.7 % respectively. Five and ten year disease-free survival was 97.6 % and 88.8 % respectively. All the recurrences occurred in the patients who received local RT (3/10) or whole brain RT (1/7) with a radiation dose of 48-50 Gy. None of the patients who received CSI suffered recurrence. There was no recurrence among the 15 patients who received < or = 45 Gy to the primary site and the 18 patients who received < or = 24 Gy (6 patients received 19.5 Gy) to the neuroaxis. CONCLUSION: CSI is recommended for the treatment of intracranial germinomas. The radiation dose can be safely decreased to < or = 45 Gy on a primay tumor site and 19.5 Gy on the spine.