Prognostic factors in hepatocellular carcinoma patients with bone metastases

PURPOSE: To identify the prognostic factors that could influence survival and to compare prognoses of the patients with the number of the risk factors that might assist in the adequate management of hepatocellular carcinoma (HCC) patients with bone metastases that showed a heterogeneous range of survival. MATERIALS AND METHODS: A total of 41 patients, treated with radiotherapy (RT) for bone metastases from HCC from 2014 to 2017, were enrolled retrospectively. Survival was determined by the Kaplan–Meier method from the start of the RT for metastatic bone lesions. Pre-RT clinical features were evaluated and their influences on survival were analyzed. The significant factors were considered to compare survivals according to the number of prognostic factors. RESULTS: Median follow-up was 6.0 months (range, 0.5 to 47.0 months). The median overall survival was 6.5 months, and the 1-year and 2-year survival rates were 35.5% and 13.5%, respectively. Multivariate analysis revealed that the Child-Pugh class A group, alpha-fetoprotein increased more than 30 ng/mL, and HCC size of more than 5 cm were associated with worse overall survival. The median survivals in HCC with none, 1, 2, and 3 of the aforementioned risk factors were 19.5, 9.0, 2.5, and 1.0 months, respectively (p < 0.05). CONCLUSION: Our results show that the overall survivals were significantly different according to the number of the risk factors among HCC patients with bone metastases who showed various lengths of survival.

Maximum diameter versus volumetric assessment for the response evaluation of vestibular schwannomas receiving stereotactic radiotherapy

PURPOSE: To explore the feasibility of maximum diameter as a response assessment method for vestibular schwannomas (VS) after stereotactic radiosurgery or fractionated stereotactic radiotherapy (RT), we analyzed the concordance of RT responses between maximum diameters and volumetric measurements. MATERIALS AND METHODS: Forty-two patients receiving curative stereotactic radiosurgery or fractionated stereotactic RT for VS were analyzed retrospectively. Twelve patients were excluded: 4 did not receive follow-up magnetic resonance imaging (MRI) scans and 8 had initial MRI scans with a slice thickness >3 mm. The maximum diameter, tumor volume (TV), and enhanced tumor volume (ETV) were measured in each MRI study. The percent change after RT was evaluated according to the measurement methods and their concordances were calculated with the Pearson correlation. The response classifications were determined by the assessment modalities, and their agreement was analyzed with Cohen kappa statistics. RESULTS: Median follow-up was 31.0 months (range, 3.5 to 86.5 months), and 90 follow-up MRI studies were analyzed. The percent change of maximum diameter correlated strongly with TV and ETV (r(p) = 0.85, 0.63, p = 0.000, respectively). Concordance of responses between the Response Evaluation Criteria in Solid Tumors (RECIST) using the maximum diameters and either TV or ETV were moderate (kappa = 0.58; 95% confidence interval, 0.32-0.85) or fair (kappa = 0.32; 95% confidence interval, 0.05-0.59), respectively. CONCLUSION: The percent changes in maximum diameter and the responses in RECIST were significantly concordant with those in the volumetric measurements. Therefore, the maximum diameters can be used for the response evaluation of VS following stereotactic RT.

Interfraction Prostate Movement in Bone Alignment After Rectal Enema for Radiotherapy

PURPOSE: To assess the effect of a rectal enema on interfraction prostate movement in bone alignment (BA) for prostate radiotherapy (RT), we analyzed the spatial difference in prostates in a bone-matched setup. MATERIALS AND METHODS: We performed BA retrospectively with data from prostate cancer patients who underwent image-guided RT (IGRT). The prostate was identified with implanted fiducial markers. The setup for the IGRT was conducted with the matching of three fiducial markers on RT planning computed tomography images and those on two oblique kV x-ray images. Offline BA was performed at the same position. The coordinates of a virtual prostate in BA and a real prostate were obtained by use of the ExaxTrac/NovalisBody system, and the distance between them was calculated as the spatial difference. Interfraction prostate displacement was drawn from the comparison of the spatial differences. RESULTS: A total of 15 patients with localized prostate cancer treated with curative hypofractionated IGRT were enrolled. A total of 420 fractions were analyzed. The mean of the interfraction prostate displacements after BA was 3.12+/-2.00 mm (range, 0.20-10.53 mm). The directional difference was profound in the anterior-posterior and supero-inferior directions (2.14+/-1.73 mm and 1.97+/-1.44 mm, respectively) compared with the right-left direction (0.26+/-0.22 mm, p<0.05). The required margin around the clinical target volume was 4.97 mm with the formula of van Herk et al. CONCLUSIONS: The interfraction prostate displacement was less frequent when a rectal enema was performed before the procedure. A rectal enema can be used to reduce interfraction prostate displacement and resulting clinical target volume-to-planning target volume margin.

Epidermal Growth Factor Receptor Is Related to Poor Survival in Glioblastomas: Single-Institution Experience

PURPOSE: There are conflicting results surrounding the prognostic significance of epidermal growth factor receptor (EGFR) status in glioblastoma (GBM) patients. Accordingly, we attempted to assess the influence of EGFR expression on the survival of GBM patients receiving postoperative radiotherapy. MATERIALS AND METHODS: Thirty three GBM patients who had received surgery and postoperative radiotherapy at our institute, between March 1997 and February 2006, were included. The evaluation of EGFR expression with immunohistochemistry was available for 30 patients. Kaplan-Meier survival analysis and Cox regression were used for statistical analysis. RESULTS: EGFR was expressed in 23 patients (76.7%), and not expressed in seven (23.3%). Survival in EGFR expressing GBM patients was significantly less than that in non-expressing patients (median survival: 12.5 versus 17.5 months, p=0.013). Patients who received more than 60 Gy showed improved survival over those who received up to 60 Gy (median survival: 17.0 versus 9.0 months, p=0.000). Negative EGFR expression and a higher radiation dose were significantly correlated with improved survival on multivariate analysis. Survival rates showed no differences according to age, sex, and surgical extent. CONCLUSION: The expression of EGFR demonstrated a significantly deleterious effect on the survival of GBM patients. Therefore, approaches targeting EGFR should be considered in potential treatment methods for GBM patients, in addition to current management strategies.

Clinical Usefulness of Implanted Fiducial Markers for Hypofractionated Radiotherapy of Prostate Cancer / 대한방사선종양학회지

PURPOSE: To assess the usefulness of implanted fiducial markers in the setup of hypofractionated radiotherapy for prostate cancer patients by comparing a fiducial marker matched setup with a pelvic bone match. MATERIALS AND METHODS: Four prostate cancer patients treated with definitive hypofractionated radiotherapy between September 2009 and August 2010 were enrolled in this study. Three gold fiducial markers were implanted into the prostate and through the rectum under ultrasound guidance around a week before radiotherapy. Glycerin enemas were given prior to each radiotherapy planning CT and every radiotherapy session. Hypofractionated radiotherapy was planned for a total dose of 59.5 Gy in daily 3.5 Gy with using the Novalis system. Orthogonal kV X-rays were taken before radiotherapy. Treatment positions were adjusted according to the results from the fusion of the fiducial markers on digitally reconstructed radiographs of a radiotherapy plan with those on orthogonal kV X-rays. When the difference in the coordinates from the fiducial marker fusion was less than 1 mm, the patient position was approved for radiotherapy. A virtual bone matching was carried out at the fiducial marker matched position, and then a setup difference between the fiducial marker matching and bone matching was evaluated. RESULTS: Three patients received a planned 17-fractionated radiotherapy and the rest underwent 16 fractionations. The setup error of the fiducial marker matching was 0.94+/-0.62 mm (range, 0.09 to 3.01 mm; median, 0.81 mm), and the means of the lateral, craniocaudal, and anteroposterior errors were 0.39+/-0.34 mm, 0.46+/-0.34 mm, and 0.57+/-0.59 mm, respectively. The setup error of the pelvic bony matching was 3.15+/-2.03 mm (range, 0.25 to 8.23 mm; median, 2.95 mm), and the error of craniocaudal direction (2.29+/-1.95 mm) was significantly larger than those of anteroposterior (1.73+/-1.31 mm) and lateral directions (0.45+/-0.37 mm), respectively (p<0.05). Incidences of over 3 mm and 5 mm in setup difference among the fractionations were 1.5% and 0% in the fiducial marker matching, respectively, and 49.3% and 17.9% in the pelvic bone matching, respectively. CONCLUSION: The more precise setup of hypofractionated radiotherapy for prostate cancer patients is feasible with the implanted fiducial marker matching compared with the pelvic bony matching. Therefore, a less marginal expansion of planning target volume produces less radiation exposure to adjacent normal tissues, which could ultimately make hypofractionated radiotherapy safer.

Clinical Implication of Cyclooxygenase-2 Expression for Rectal Cancer Patients with Lymph Node Involvement / 대한방사선종양학회지

PURPOSE: To assess the influence of cyclooxygenase-2 (COX-2) expression on the survival of patients with a combination of rectal cancer and lymph node metastasis. MATERIALS AND METHODS: The study included rectal cancer patients treated by radical surgery and postoperative radiotherapy at the Dong-A university hospital from 1998 to 2004. A retrospective analysis was performed on a subset of patients that also had lymph node metastasis. After excluding eight of 86 patients, due to missing tissue samples in three, malignant melanoma in one, treatment of gastric cancer around one year before diagnosis in one, detection of lung cancer after one year of diagnosis in one, liver metastasis in one, and refusal of radiotherapy after 720 cGy in one, 78 patients were analyzed. The immunohistochemistry for COX-2 was conducted with an autostainer (BenchMark; Ventana, Tucson, AZ, USA). An image analyzer (TissueMine; Bioimagene, Cupertino, CA, USA) was used for analysis after scanning (ScanScope; Aperio, Vista, CA, USA). A survival analysis was performed using the Kaplan Meier method and significance was evaluated using the log rank test. RESULTS: COX-2 was stained positively in 62 patients (79.5%) and negatively in 16 (20.5%). A total of 6 (7.7%), 15 (19.2%), and 41 (52.6%) patients were of grades 1, 2, and 3, respectively for COX-2 expression. No correlation was found between being positive of COX-2 patient characteristics, which include age ( or =60), sex, operation methods (abdominoperineal resection vs. lower anterior resection), degrees of differentiation, tumor size ( or =5 cm), T stages, N stages, and stages (IIIa, IIIb, IIIc). The 5-year overall and 5-year disease free survival rates for the entire patient population were 57.0% and 51.6%, respectively. The 5-year overall survival rates for the COX-2 positive and negative patients were 53.0% and 72.9%, respectively (p=0.146). Further, the 5-year disease free survival rates for the COX-2 positive and negative patients were 46.3% and 72.7%, respectively (p=0.118). The 5-year overall survival rates were significantly different (p<0.05) for the degree of differentiation, N stage, and stage, whereas the 5-year disease free survival rates were significant for N stage and stage. CONCLUSION: Being positive for and the degree of COX-2 expression did not have a significant influence on the survival of rectal cancer patients with lymph node metastasis. However, N stage and stage did significantly influence the rateof survival. Further analysis of a greater sample size is necessary for the verification of the effect of COX-2 expression on the survival of rectal cancer patients with lymph node involvement.

Comparative Analysis of Patterns of Care Study of Radiotherapy for Esophageal Cancer among Three Countries: South Korea, Japan and the United States / 대한방사선종양학회지

PURPOSE: For the first time, a nationwide survey of the Patterns of Care Study (PCS) for the various radiotherapy treatments of esophageal cancer was carried out in South Korea. In order to observe the different parameters, as well as offer a solid cooperative system, we compared the Korean results with those observed in the United States (US) and Japan. MATERIALS AND METHODS: Two hundreds forty-six esophageal cancer patients from 21 institutions were enrolled in the South Korean study. The patients received radiation theraphy (RT) from 1998 to 1999. In order to compare these results with those from the United States, a published study by Suntharalingam, which included 414 patients [treated by Radiotherapy (RT)] from 59 institutions between 1996 and 1999 was chosen. In order to compare the South Korean with the Japanese data, we choose two different studies. The results published by Gomi were selected as the surgery group, in which 220 esophageal cancer patients were analyzed from 76 facilities. The patients underwent surgery and received RT with or without chemotherapy between 1998 and 2001. The non-surgery group originated from a study by Murakami, in which 385 patients were treated either by RT alone or RT with chemotherapy, but no surgery, between 1999 and 2001. RESULTS: The median age of enrolled patients was highest in the Japanese non-surgery group (71 years old). The gender ratio was approximately 9:1 (male:female) in both the Korean and Japanese studies, whereas females made up 23.1% of the study population in the US study. Adenocarcinoma outnumbered squamous cell carcinoma in the US study, whereas squamous cell carcinoma was more prevalent both the Korean and Japanese studies (Korea 96.3%, Japan 98%). An esophagogram, endoscopy, and chest CT scan were the main modalities of diagnostic evaluation used in all three countries. The US and Japan used the abdominal CT scan more frequently than the abdominal ultrasonography. Radiotherapy alone treatment was most rarely used in the US study (9.5%), compared to the Korean (23.2%) and Japanese (39%) studies. The combination of the three modalities (Surgery+RT+Chemotherapy) was performed least often in Korea (11.8%) compared to the Japanese (49.5%) and US (32.8%) studies. Chemotherapy (89%) and chemotherapy with concurrent chemoradiotherapy (97%) was most frequently used in the US study. Fluorouracil (5-FU) and Cisplatin were the most preferred drug treatments used in all three countries. The median radiation dose was 50.4 Gy in the US study, as compared to 55.8 Gy in the Korean study regardless of whether an operation was performed. However, in Japan, different median doses were delivered for the surgery (48 Gy) and non-surgery groups (60 Gy). CONCLUSION: Although some aspects of the evaluation of esophageal cancer and its various treatment modalities were heterogeneous among the three countries surveyed, we found no remarkable differences in the RT dose or technique, which includes the number of portals and energy beams.

Impact of Cyclooxygenase-2 Expression on the Survival of Glioblastoma / 대한방사선종양학회지

PURPOSE: To investigate the degree and effect of cyclooxygenase (COX)-2 expression on the survival of patients with glioblastoma multiforme (GM). MATERIALS AND METHODS: Between 1997 and 2006, thirty consecutive GM patients treated with surgery and postoperative radiotherapy (dose range: 44~65.1 Gy, median dose: 61.2 Gy) were included in the study. Three patients were excluded that discontinued radiotherapy before receiving a dose of 40 Gy due to mental deterioration. The expression of the COX-2 protein in surgical specimens was examined by immunohistochemical analysis. Survival analysis and verification were performed with respect to sex, age, performance status, resection extent, radiotherapy dose, and degree of COX-2 expression using the Kaplan-Meier method and the log rank test. RESULTS: The median length of follow-up was 13.3 months (range: 6~83 months). Staining for COX-2 was positive in all patient samples. Staining for COX-2 that was positive for over 75% of the tumor cells was found in 24 patients. Staining for COX-2 that was positive in less than 25% of tumor cells was found in 3 patients (10.0%), staining for COX-2 that was positive in 25 to 50% of tumor cells was found in 1 patient (3.3%), staining for COX-2 that was positive in 50 to 75% of tumor cells was found in 2 patients (6.7%) and staining for COX-2 that was positive in 75 to 100% of tumor cells was found in 24 patients (80.0%). The median survival and two-year survival rate were 13.5 months and 17.5%, respectively. The survival rate was influenced significantly by the degree of resection (tumor removal by 50% or more) and radiotherapy dose (59 Gy or greater) (p0.05), and the two-year survival for these groups was 33.3 and 13.3%, respectively (p>0.05). CONCLUSION: The absence of a statistical correlation between the degree of COX-2 expression and survival in GM patients, despite the high rate of COX-2 positive tumor cells in the GM patient samples, requires further studies with a larger series to ascertain the prognostic value of the degree of COX-2 expression in GM patients.

Preliminary Report of the 1998~1999 Patterns of Care Study of Radiation Therapy for Esophageal Cancer in Korea / 대한방사선종양학회지

PURPOSE: For the first time, a nationwide survey in the Republic of Korea was conducted to determine the basic parameters for the treatment of esophageal cancer and to offer a solid cooperative system for the Korean Pattern of Care Study database. MATERIALS AND METHODS: During 1998~1999, biopsy-confirmed 246 esophageal cancer patients that received radiotherapy were enrolled from 23 different institutions in South Korea. Random sampling was based on power allocation method. Patient parameters and specific information regarding tumor characteristics and treatment methods were collected and registered through the web based PCS system. The data was analyzed by the use of the Chi-squared test. RESULTS: The median age of the collected patients was 62 years. The male to female ratio was about 91 to 9 with an absolute male predominance. The performance status ranged from ECOG 0 to 1 in 82.5% of the patients. Diagnostic procedures included an esophagogram (228 patients, 92.7%), endoscopy (226 patients, 91.9%), and a chest CT scan (238 patients, 96.7%). Squamous cell carcinoma was diagnosed in 96.3% of the patients; mid-thoracic esophageal cancer was most prevalent (110 patients, 44.7%) and 135 patients presented with clinical stage III disease. Fifty seven patients received radiotherapy alone and 37 patients received surgery with adjuvant postoperative radiotherapy. Half of the patients (123 patients) received chemotherapy together with RT and 70 patients (56.9%) received it as concurrent chemoradiotherapy. The most frequently used chemotherapeutic agent was a combination of cisplatin and 5-FU. Most patients received radiotherapy either with 6 MV (116 patients, 47.2%) or with 10 MV photons (87 patients, 35.4%). Radiotherapy was delivered through a conventional AP-PA field for 206 patients (83.7%) without using a CT plan and the median delivered dose was 3,600 cGy. The median total dose of postoperative radiotherapy was 5,040 cGy while for the non-operative patients the median total dose was 5,970 cGy. Thirty-four patients received intraluminal brachytherapy with high dose rate Iridium-192. Brachytherapy was delivered with a median dose of 300 cGy in each fraction and was typically delivered 3~4 times. The most frequently encountered complication during the radiotherapy treatment was esophagitis in 155 patients (63.0%). CONCLUSION: For the evaluation and treatment of esophageal cancer patients at radiation facilities in Korea, this study will provide guidelines and benchmark data for the solid cooperative systems of the Korean PCS. Although some differences were noted between institutions, there was no major difference in the treatment modalities and RT techniques.

Intensity Modulated Whole Pelvic Radiotherapy in Patients with Cervix Cancer: Analysis of Acute Toxicity / 대한방사선종양학회지

PURPOSE: To evaluate acute toxicities in cervix cancer patients receiving intensity modulated whole pelvic radiation therapy (IM-WPRT). MATERIALS AND METHODS: Between August 2004 and April 2006, 17 patients who underwent IM-WPRT were analysed. An intravenous contrast agent was used for radiotherapy planning computed tomography (CT). The central clinical target volume (CTV) included the primary tumor, uterus, vagina, and parametrium. The nodal CTV was defined as the lymph nodes larger than 1 cm seen on CT and the contrased-enhanced pelvic vessels. The planning target volume (PTV) was the 1-cm expanded volume around the central CTV, except for a 5-mm expansion from the posterior vagina, and the nodal PTV was defined as the nodal CTV plus a 1.5 cm margin. IM-WPRT was prescribed to deliver a dose of 50 Gy to more than 95% of the PTV. Acute toxicity was assessed with common toxicity criteria up to 60 days after radiotherapy. RESULTS: Grade 1 nausea developed in 10 (58.9%) patients, and grade 1 and 2 diarrhea developed in 11 (64.7%) and 1 (5.9%) patients, respectively. No grade 3 or higher gastrointestinal toxicity was seen. Leukopenia, anemia, and thrombocytopenia occurred in 15 (88.2%). 7 (41.2%), and 2 (11.8%) patients, respectively, as hematologic toxicities. Grade 3 leukopenia developed in 2 patients who were treated with concurrent chemoradiotherapy. CONCLUSION: IM-WPRT can be a useful treatment for cervix cancer patients with decreased severe acute toxicities and a resultant improved compliance to whole pelvic irradiation.

Impact of Intensity Modulated Radiation Therapy as aBoost Treatment on the Lung Dose Distributions for Non-Small-Cell Lung Cancer

PURPOSE : To investigate the feasibility of intensity modulated radiotherapy (IMRT) as a method of boost radiotherapy following the initial irradiation by the conventional anterior / posterior opposed beams for centrally located non-small-cell lung cancer through the evaluation of dose distributions according to the various boost methods. MATERIALS AND METHODS : Seven patients with T3 or T4 lung cancer and mediastinal node enlargement who previously received radiotherapy were studied. All patients underwent virtual simulation retrospectively with the previous treatment planning CTs. Initial radiotherapy plans were designed to deliver 40 Gy to the primary tumor and involved nodal regions with the conventional anterior / posterior opposed beams. Two radiation dose levels, 24 and 30 Gy, were used for the boost radiotherapy plans, and 4 different boost methods (a three dimensional conformal radiotherapy (3DCRT), 5, 7, and 9-beams IMRT) were applied to each dose level. The goals of the boost plans were to deliver the prescribed radiation dose to 95% of the planning target volume (PTV) and minimize the volumes of the normal lungs and spinal cord irradiated above their tolerance doses. Dose distributions in the PTVs and lungs, according to the four types of boost plans, were compared in the boost and sum plans, respectively. RESULTS : The percentage of lung volumes irradiated >20 Gy (V20) were reduced significantly in the IMRT boost plans compared with the 3DCRT boost plans at the 24 and 30 Gy dose levels (p=0.007 and 0.031 respectively). Mean lung doses according to the boost methods were not different in the 24 and 30 Gy boost plans. The conformity indexes (CI) of the IMRT boost plans were lower than those of the 3DCRT plans in the 24 and 30 Gy plans (p=0.001 in both). For the sum plans, there was no difference of the dose distributions in the PTVs and lungs according to the boost methods. CONCLUSION : In the boost plans the V20s and CIs were reduced significantly by the IMRT plans, but in the sum plans the effects of IMRT to the dose distributions in the tumor and lungs, like CI and V20, were offset. Therefore, in order to keep the beneficial effect of IMRT in radiotherapy for lung cancer, it would be better to use IMRT as a whole treatment plan rather than as a boost treatment

Stem Cells Expressing Homing Receptors Could be Expanded From Cryopreserved and Unselected Cord Blood

We assessed the cytokine combinations that are best for ex vivo expansion of cord blood (CB) and the increment for cell numbers of nucleated cells, as well as stem cells expressing homing receptors, by an ex vivo expansion of cryopreserved and unselected CB. Frozen leukocyte concentrates (LC) from CB were thawed and cultured at a concentration of 1x10(5)/mL in media supplemented with a combination of SCF (20 ng/mL)+TPO (50 ng/mL)+FL (50 ng/mL)+/-IL-6 (20 ng/mL)+/-G-CSF (20 ng/mL). After culturing for 14 days, the expansion folds of cell numbers were as follows: TNC 22.3+/-7.8~26.3+/-4.9, CFU-GM 4.7+/-5.1~11.7+/-2.6, CD34+CD38- cell 214.0+/-251.9~464.1+/-566.1, CD34+CXCR4+ cell 4384.5+/-1664.7~7087.2+/-4669.3, CD34+VLA4+ cell 1444.3+/-1264.0~2074.9+/-1537.0, CD34+VLA5+ cell 86.2+/-50.9~ 113.2+/-57.1. These results revealed that the number of stem cells expressing homing receptors could be increased by an ex vivo expansion of cryopreserved and unselected CB using 3 cytokines (SCF, TPO, FL) only. Further in vivo studies regarding the engraftment after expansion of the nucleated cells, as well as the stem cells expressing homing receptors will be required.

A Web-based 'Patterns of Care Study' System for Clinical Radiation Oncology in Korea: Development, Launching, and Characteristics / 대한방사선종양학회지

PURPOSE: We report upon a web-based system for Patterns of Care Study (PCS) devised for Korean radiation oncology. This PCS was designed to establish standard tools for clinical quality assurance, to determine basic parameters for radiation oncology processes, to offer a solid system for cooperative clinical studies and a useful standard database for comparisons with other national databases. MATERIALS AND METHODS: The system consisted of a main server with two back-ups in other locations. The program uses a Linux operating system and a MySQL database. Cancers with high frequencies in radiotherapy departments in Korea from 1998 to 1999 were chosen to have a developmental priority. RESULTS: The web-based clinical PCS system for radiotherapy in www.pcs.re.kr was developed in early 2003 for cancers of the breast, rectum, esophagus, larynx and lung, and for brain metastasis. The total number of PCS study items exceeded one thousand. Our PCS system features user-friendliness, double entry checking, data security, encryption, hard disc mirroring, double back-up, and statistical analysis. Alphanumeric data can be input as well as image data. In addition, programs were constructed for IRB submission, random sampling of data, and departmental structure. CONCLUSION: For the first time in the field of PCS, we have developed a web-based system and associated working programs. With this system, we can gather sample data in a short period and thus save, cost, effort and time. Data audits should be performed to validate input data. We propose that this system should be considered as a standard method for PCS or similar types of data collection systems.

Regulatory Mechanism of Radiation-induced Cancer Cell Death by the Change of Cell Cycle / 대한방사선종양학회지

PURPOSE: In our previous study, we have shown the main cell death pattern induced by irradiation or protein tyrosine kinase (PTK) inhibitors in K562 human myelogenous leukemic cell line. Death of the cells treated with irradiation alone was characterized by mitotic catastrophe and typical radiation-induced apoptosis was accelerated by herbimycin A (HMA). Both types of cell death were inhibited by genistein. In this study, we investigated the effects of HMA and genistein on cell cycle regulation and its correlation with the alterations of radiation-induced cell death. MATERIALS AND METHODS: K562 cells in exponential growth phase were used for this study. The cells were irradiated with 10 Gy using 6 MeV Linac (200-300 cGy/min). Immediately after irradiation, cells were treated with 250 nM of HMA or 25 microM of genistein. The distributions of cell cycle, the expressions of cell cycle-related protein, the activities of cyclin-dependent kinase, and the yield of senescence and differentiation were analyzed. RESULTS: X-irradiated cells were arrested in the G2 phase of the cell cycle but unlike the p53-positive cells, they were not able to sustain the cell cycle arrest. An accumulation of cells in G2 phase of first cell-cycle post-treatment and an increase of cyclin B1 were correlated with spontaneous, premature, chromosome condensation and mitotic catastrophe. HMA induced rapid G2 checkpoint abrogation and concomitant p53-independent G1 accumulation. HMA-induced cell cycle modifications correlated with the increase of cdc2 kinase activity, the decrease of the expressions of cyclins E and A and of CDK2 kinase activity, and the enhancement of radiation-induced apoptosis. Genistein maintained cells that were arrested in the G2-phase, decreased the expressions of cyclin B1 and cdc25C and cdc2 kinase activity, increased the expression of p16, and sustained senescence and megakaryocytic differentiation. CONCLUSION: The effects of HMA and genistein on the radiation-induced cell death of K562 cells were closely related to the cell cycle regulatory activities. In this study, we present a unique and reproducible model in which for investigating the mechanisms of various, radiation-induced, cancer cell death patterns. Further evaluation by using this model will provide a potent target for a new strategy of radiotherapy.

Signal Transduction Factors on the Modulation of Radiosusceptibility in K562 Cells / 대한방사선종양학회지

PURPOSE: The human chronic myelogenous leukemia cell line, K562, expresses the chimeric bcr-abl oncoprotein, whose deregulated protein tyrosine kinase activity antagonizes the induction of apoptosis via DNA damaging agents. Previous experiments have shown that nanomolar concentrations of herbimycin A (HMA) coupled with X-irradiation have a synergistic effect in inducing apoptosis in the Ph-positive K562 leukemia cell line, but genistein, a PTK inhibitor, is non selective for the radiation-induced apoptosis of p210bcr/abl protected K562 cells. In these experiments, the cytoplasmic signal transduction pathways, the induction of a number of transcription factors and the differential gene expression in this model were investigated. MATERIALS AND METHODS: K562 cells in the exponential growth phase were used in this study. The cells were irradiated with 0.5-12 Gy, using a 6 MeV Linac (Clinac 1800, Varian, USA). Immediately after irradiation, the cells were treated with 0.25 microM of HMA and 25 microM of genistein, and the expressions and the activities of abl kinase, MAPK family, NF-kB, c-fos, c-myc, and thymidine kinase1 (TK1) were examined. The differential gene expressions induced by PTK inhibitors were also investigated. RESULTS: The modulating effects of herbimycin A and genistein on the radiosensitivity of K562 cells were not related to the bcr-abl kinase activity. The signaling responses through the MAPK family of proteins, were not involved either. In association with the radiation-induced apoptosis, which is accelerated by HMA, the expression of c-myc was increased. The combined treatment of genistein, with irradiation, enhanced NF-kB activity and the TK1 expression and activity. CONCLUSION: The effects of HMA and genistein on the radiosensitivity of the K562 cells were not related to the bcr-abl kinase activity. In this study, another signaling pathway, besides the MAPK family responses to radiation to K562 cells, was found. Further evaluation using this model will provide valuable information for the optional radiosensitization or radioprotection.

A Novel Chenodeoxycholic Derivative HS-1200 Induces Apoptosis in Human HT-29 Colon Cancer Cells / 대한방사선종양학회지

PURPOSE: To investigate the growth inhibitory effects, and the underlying mechanism of human colon cancer cell (HT-29) death, induced by a new synthetic bile acid derivative (HS-1200). MATERIALS AND METHODS: Human colon cancer cells (HT-29), in exponential growth phase, were treated with various concentrations of a new synthetic bile acid derivative (HS-1200). The growth inhibitory effects on HT-29 cells were examined using a trypan blue exclusion assay. The extent of apoptosis was determined using agarose gel electrophoresis, TUNEL assays and Hoechst staining. The apoptotic cell death was also confirmed by Western blotting of PARP, caspase-3 and DNA fragmentation factor (DFF) analysis. To investigate the involvement of mitochondria, we employed immunofluorescent staining of cytochrome c and mitochondrial membrane potential analyses. RESULTS: The dose required for the half maximal inhibition (IC50) of the HT-29 cell growth was 100~150 micro M of HS-1200. Several changes, associated with the apoptosis of the HT-29 cells, were reveal by the agarose gel eletrophoresis, TUNEL assays and Hoechst staining, following their treatment with 100 micro M of HS-1200. HS-1200 treatment also induced caspase-3, PARP and DFF degradations, and the western blotting showed the processed caspase-3 p20, PARP p85 and DFF p30 and p11 cleaved products. Mitochondrial events were also demonstrated. The cytochrome c staining indicated that cytochrome c had been released from the mitochondria in the HS-1200 treated cells. The mitochondrial membrane potential (deltaxm) was also prominently decreased in the HS-1200 treated cells. CONCLUSION: These findings suggest that the HS-1200 - induced apoptosis of human colon cancer cells (HT-29) is mediated via caspase and mitochondrial pathways.

A study for time sequential expression of IL-1 alphaand IL-6 after irradiation on rat lung / 대한내과학회지

BACKGROUND: One of the limitation during the irradiation of malignant tumor is hazard to normal tissue although it is important and effective tool for treating malignant tumor. We studied the role of interleukin-1 alpha (IL-1alpha) and interleukin-6 (IL-6) in the radiation-induced lung injury especially on fibrosis. METHODS: We irradiated right-side lungs of thirty Sprague-Dawley rats with single fraction of 20 Gy and then sacrificed the animals until 20th week at intervals of two weeks. Both irradiated and unirradiated lung tissues were stained hematoxilin and eosin, Masson trichrome, reticulin and immunohistochemical staining for IL-1alpha and IL-6. The degree of the staining for IL-1alpha and IL-6 were examined semiquantitatively. RESULTS: Two weeks after irradiation interstitial edema and capillary congestion appeared, followed by increase of the monocytes infiltration and proteinaceous material during 4th and 8th week. After eight weeks of irradiation, collagen and reticulin fibers were detected along alveolar wall. 12th to 20th week, fibrosis in interstitium, decreased number of alveoli and thickening of bronchial wall were observed. The degree of immunohistochemical staining for IL-1alpha and IL-6 was increased rapidly during the first three week and then decreased slowly, but remain incresed until 20th week. CONCLUSION: Our Study demonstrate the early and persistent elevation of cytokines IL-1alpha and IL-6 by immunohistochemical stain in rat lung following pulmonary irradiation. We think cytokines are produced immediately after irradiation, make collagen genes turn on and perisist until the expression of late effects become apparent pathologically and clinically.

Combined Modality Therapy with Selective Bladder Preservation for Muscle Invading Bladder Cancer / 대한방사선종양학회지

PURPOSE: To assess the tolerance, complete response rate, bladder preservation rate and survival rate in patients with muscle-invading bladder cancer treated with selective bladder preservation protocol. METHOD AND MATERIALS: From October 1990 to June 1998, twenty six patients with muscle-invading bladder cancer (clinical stage T2-4, N0-3, M0) were enrolled for the treatment protocol of bladder preservation. They were treated with maximal TURBT (transurethral resection of bladder tumor) and 2 cycles of MCV chemotherapy (methotrexate, crisplatin, and vinblastine) followed by 39.6~45 Gy pelvic irradiation with concomitant cisplatin. After complete urologic evaluation (biopsy or cytology), the patients who achieved complete response were planed for bladder preservation treatment and treated with consolidation cisplatin and radiotherapy (19.8 Gy). The patients who had incomplete response were planed to immediate radical cystectomy. If they refused radical cystectomy, they were treated either with TURBT followed by MCV or cisplatin chemotherapy and radiotherapy. The median follow-up duration is 49.5 months. RESULT: The patients with stage T2-3a and T3b-4a underwent complete removal of tumor or gross tumor removal by TURBT, respectively. Twenty one out of 26 patients (81%) successfully completed the protocol of the planned chemo-radiotherapy. Seven patients had documented complete response. Six of them were treated with additional consolidation cisplatin and radiotherapy. One patient was treated with 2 cycles of MCV chemotherapy due to refusal of chemo-radiotherapy. Five of 7 complete responders had functioning tumor-free bladder. Fourteen patients of incomplete responders were further treated with one of the followings : radical cystectomy (1 patient), or TURBT and 2 cycles of MCV chemotherapy (3 patients), or cisplatin and radiotherapy (10 patients). Thirteen patients of them were not treated with planned radical cystectomy due to patients' refusal (9 patients) or underlying medical problems (4 patients). Among twenty one patients, 12 patients (58%) were alive with their preserved bladder, 8 patients died with the disease, 1 patient died of intercurrent disease. The 5 years actuarial survival rates according to CR and PR after MCV chemotherapy and cisplatin chemoradiotherapy were 80% and 14%, respectively (p=0.001). CONCLUSION: In selected patients with muscle-invading bladder cancer, the bladder preservation could be achieved by MCV chemotherapy and cisplatin chemo-radiotherapy. All patients tolerated well this bladder preservation protoco. The availability of complete TURBT and the responsibility of neoadjuvant chemotherapy and chemoradiotherapy were important predictors for bladder preservation and survival. The patients who had not achieved complete response after neoadjuvant chemotherapy and chemoradiotherapy should be immediate radical cystectomy. A randomized prospective trial might be essential to determine more accurate indications between cystectomy or bladder preservation.

Smad6 Gene and Suppression of Radiation-Induced Apoptosis by Genistein in K562 cells / 대한방사선종양학회지

PURPOSE: The genes involved on the suppression of radiation-induced apoptosis by genistein in K562 leukemia cell line was investigated. MATERIALS AND METHODS: K562 cells in exponential growth phase were irradiated with a linear accelerator at room temperature. Forx-ray irradiation and drug treatment, cultures were prepared at 2x105 cells/mL. The cells were irradiated with 10 Gy (Clinac 1800C, Varian, USA). Stock solutions of herbimycin A (HMA, Calbiochem, UK) and genistein (Calbiochem, UK) were prepared in dimethylsulfoxide (DMSO, Sigma, UK). After incubation at 37degreesC for 24 h, PCR-select cDNA subtractive hybridization, dot hybridization, DNA sequencing and Northern hybridization were examined. RESULTS: Smad6 gene was identified from the differentially expressed genes in K562 cells incubated with genistein which had been selected by PCR-select cDNA subtractive hybridization. The mRNA expression of Smad6 in K562 cells incubated with genistein was also higher than control group by Northern hybridization analysis. CONCLUSION: We have shown that Smad6 involved on the suppression of radiation-induced apoptosis by genistein in K562 leukemia cell line. It is plausible that the relationship between Smad6 and the suppression of radiation-induced apoptosis is essential for treatment development based on molecular targeting designed to modify radiation-induced apoptosis.

The Role of Primary Radiotherapy for Squamous Cell Carcinoma of the Supraglottic Larynx / 대한방사선종양학회지

BACKGROUND: First of all, this study was performed to assess the result of curative radiotherapy and to evaluate different possible prognostic factors for squamous cell carcinoma of the supraglottic larynx treated at the Pusan National University Hospital. The second goal of this study was by comparing our data with those of other study groups, to determine the better treatment policy of supraglottic cancer in future. METHODS AND MATERIALS: Thirty-two patients with squamous cell carcinoma of the supraglottic larynx were treated with radiotherapy at Pusan National University Hospital, from August 1985 to December 1996. Minimum follow-up period was 29 months. Twenty-seven patients (84.4%) were followed up over 5 years. Radiotherapy was delivered with 6 MV photons to the primary laryngeal tumor and regional lymphatics with shrinking field technique. All patients received radiotherapy under conventional fractionated schedule (once a day). Median total tumor dose was 70.2 Gy (range, 55.8 to 75.6 Gy) on primary or gross tumor lesion. Thirteen patients had induction chemotherapy with cisplatin and 5-fluorouracil (1-3 cycles). Patient distribution, according to the different stages, were as follows: stage I, 5/32 (15.6%); stage II, 10/32 (31.3%); stage III, 8/32 (25%); stage IV, 9/32 (28.1%). RESULTS: The 5-year overall survival rate of the whole series (32 patients) was 51.7%. The overall survival rate at 5-years was 80% in stage I, 66.7% in stage II, 42.9% in stage III, 25% in stage IV ( p= 0.0958). The 5-year local control rates after radiotherapy were as follows: stage I, 100%; stage II, 60%; stage III, 62.5%; stage IV, 44.4% ( p=0.233). Overall vocal preservation rates was 65.6%, 100% in stage I, 70% in stage II, 62.5% in stage III, 44.4% in stage IV ( p=0.210). There was no statistical significance in survival and local control rate between neoadjuvant chemotherapy followed by radiotherapy group and radiotherapy alone group. Severe laryngeal edema was found in 2 cases after radiotherapy, emergent tracheostomy was done. Four patients were died from distant metastsis, : three in lung, one in brain. Double primary tumor was found in 2 cases, one in lung (metachronous), another in thyroid (synchronous). Ulcerative lesions were revealed as unfavorable prognostic factor ( p=0.0215), and radiation dose (more or less than 70.2 Gy) was an important factor on survival ( p=0.0302). CONCLUSIONS: The role of radiotherapy in the treatment of supraglottic carcinoma is to improve the survival and to preserve the laryngeal function. Based on our data and other studies, early and moderately advanced supraglottic carcinomas could be successfully treated with either conservative surgery or radiotherapy alone. Both modalities showed similar results in survival and vocal preservation. For the advanced cases, radiotherapy alone is inadequate for curative aim and surgery combined with radiotherapy should be done in operable patients. When patients refuse operation or want to preserve vocal function, or for the patients with inoperable medical conditions, combined chemoradiotherapy (concurrent) or altered fractionated radiotherapy with or without radiosensitizer should be taken into consideration in future.