Clinical Significance of FDG PET-CT Scan at 12 Weeks after Curative Radiation Therapy in Patients with Head and Neck Cancer / 대한두경부종양학회지

Background/Objectives@#To evaluate clinical significance of FDG PET-CT for detection of residual cancer cells after curative radiation therapy or chemoradiotherapy for patients with squamous cell carcinoma (SCC) of Head and NeckMaterials & Methods: A retrospective analysis of patients with SCC of Head and neck with curative radiotherapy or chemoradiotherpy between June 2011 and Jan. 2019 was performed. Sixty patients were treated with Intensity-modulated radiotherapy (IMRT). The Metabolic responses were evaluated on the post-treatment FDG PET-CT at 12 weeks after curative radiotherapy completion. @*Results@#Median follow up was 51.5 months (3-102). The overall survival (OS), disease free survival (DFS), local control rate (LCR), and Distant metastasis free survival (DMFS) at 5 years were 80.5%, 80.1%, 87.7% and 89.1%. Metabolic CR was found in 43 (71.7%) and partial metabolic response (PR) was noted in 17 (14.6%). Metabolic CR was significantly correlated with OS, DFS, LCR, and DMFS. On multivariate analysis, Metabolic CR remained significant for DFS and LCR. @*Conclusion@#Metabolic CR on post-radiotherapy FDG PET-CT is highly predictive of increased DFS and LCR in patients with head and neck cancer.

Clinical Significance of FDG PET-CT Scan at 12 Weeks after Curative Radiation Therapy in Patients with Head and Neck Cancer / 대한두경부종양학회지

Background/Objectives@#To evaluate clinical significance of FDG PET-CT for detection of residual cancer cells after curative radiation therapy or chemoradiotherapy for patients with squamous cell carcinoma (SCC) of Head and NeckMaterials & Methods: A retrospective analysis of patients with SCC of Head and neck with curative radiotherapy or chemoradiotherpy between June 2011 and Jan. 2019 was performed. Sixty patients were treated with Intensity-modulated radiotherapy (IMRT). The Metabolic responses were evaluated on the post-treatment FDG PET-CT at 12 weeks after curative radiotherapy completion. @*Results@#Median follow up was 51.5 months (3-102). The overall survival (OS), disease free survival (DFS), local control rate (LCR), and Distant metastasis free survival (DMFS) at 5 years were 80.5%, 80.1%, 87.7% and 89.1%. Metabolic CR was found in 43 (71.7%) and partial metabolic response (PR) was noted in 17 (14.6%). Metabolic CR was significantly correlated with OS, DFS, LCR, and DMFS. On multivariate analysis, Metabolic CR remained significant for DFS and LCR. @*Conclusion@#Metabolic CR on post-radiotherapy FDG PET-CT is highly predictive of increased DFS and LCR in patients with head and neck cancer.

Clinical Outcomes of Postoperative Radiotherapy Following Radical Prostatectomy in Patients with Localized Prostate Cancer: A Multicenter Retrospective Study (KROG 18-01) of a Korean Population / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The purpose of this study was to investigate the clinical outcomes of postoperative radiotherapy (PORT) patients who underwent radical prostatectomy for localized prostate cancer. @*Materials and Methods@#Localized prostate cancer patients who received PORT after radical prostatectomy between 2001 and 2012 were identified retrospectively in a multi-institutional database. In total, 1,117 patients in 19 institutions were included. Biochemical failure after PORT was defined as prostate-specific antigen (PSA) ≥ nadir+2 after PORT or initiation of androgen deprivation therapy (ADT) for increasing PSA regardless of its value. @*Results@#Ten-year biochemical failure-free survival, clinical failure-free survival, distant metastasisfree survival, overall survival (OS), and cause-specific survival were 60.5%, 76.2%, 84.4%, 91.1%, and 96.6%, respectively, at a median of 84 months after PORT. Pre-PORT PSA ≤ 0.5 ng/ml and Gleason’s score ≤ 7 predicted favorable clinical outcomes, with 10-year OS rates of 92.5% and 94.1%, respectively. The 10-year OS rate was 82.7% for patients with a PSA > 1.0 ng/mL and 86.0% for patients with a Gleason score of 8-10. The addition of longterm ADT (≥ 12 months) to PORT improved OS, particularly in those with a Gleason score of 8-10 or ≥ T3b. @*Conclusion@#Clinical outcomes of PORT in a Korean prostate cancer population were very similar to those in Western countries. Lower Gleason score and serum PSA level at the time of PORT were significantly associated with favorable outcomes. Addition of long-term ADT (≥ 12 months) to PORT should be considered, particularly in unfavorable risk patients with Gleason scores of 8-10 or ≥ T3b.

Radiation Recall Dermatitis after Treatment with Paclitaxel and Cisplatin

No abstract available.

Retrospective analysis of treatment outcomes after postoperative chemoradiotherapy in advanced gastric cancer

PURPOSE: To evaluate retrospectively the survival outcome, patterns of failure, and complications in patients treated with postoperative chemoradiotherapy (CRT) in advanced gastric cancer. MATERIALS AND METHODS: Between January 2000 and December 2006, 80 patients with advanced gastric cancer who received postoperative concurrent CRT were included. Pathological staging was IB-II in 9%, IIIA in 38%, IIIB in 33%, and IV in 21%. Radiotherapy consisted of 45 Gy of radiation. Concurrent chemotherapy consisted of a continuous intravenous infusion of 5-fluorouracil and leucovorin on the first 4 days and last 3 days of radiotherapy. RESULTS: The median follow-up period was 48 months (range, 3 to 83 months). The 5-year overall survival, disease-free survival, and locoregional recurrence-free survivals were 62%, 59%, and 80%, respectively. In the multivariate analysis, significant factors for disease-free survival were T stage (hazard ratio [HR], 0.278; p = 0.038), lymph node dissection extent (HR, 0.201; p = 0.002), and maintenance oral chemotherapy (HR, 2.964; p = 0.004). Locoregional recurrence and distant metastasis occurred in 5 (6%) and 18 (23%) patients, respectively. Mixed failure occurred in 10 (16%) patients. Grade 3 leukopenia and thrombocytopenia were observed in 4 (5%) and one (1%) patient, respectively. Grade 3 nausea and vomiting developed in 8 (10%) patients. Intestinal obstruction developed in one (1%). CONCLUSION: The survival outcome of the postoperative CRT in advanced gastric cancer was similar to those reported previously. Our postoperative CRT regimen seems to be a safe and effective method, reducing locoregional failure without severe treatment toxicity in advanced gastric cancer patients.

Accuracy Evaluation of Treatment Planning System Using Irregular-surface Water Phantom / 의학물리

We evaluated on the calculation accuracy of treatment planning system (TPS) with phantom having convex and concave surface. The TPS is Eclipse (Varian, USA) using both algorithms AAA and PBC for photon dose calculations. PBC algorithms have three corrections of Batho, modified Batho (M-Batho), and equivalent TAR (E-TAR). The field sizes were 10x10 cm2 and 20x20 cm2, and MLC-shaped fields for these fields. We measured doses at three depths 5, 10 and 15 cm in phantom of SSD=90 cm in the condition of inserted farmer chamber. For given conditions, we have calculated dose with these algorithms and compared them with measured doses. In AAA the calculated doses (dose/MU) were agreed to measured doses within +/-1% in flat and convex surface and were under estimated with -1.9% maximum in concave surface. In PBC the calculated doses were over estimated with +1.7% and +4.1% respectively in flat and convex surface and the differences were from -3.1% to +2.1% in concave surface. In comparison of criteria from AAPM and IAEA reports, and statistical analysis for these results, it is found that the AAA's results are in good agreement with measured values and the M-Batho's results are generally good agreed with measured values among PBC algorithms.

The Clinical Significance of Cathepsin D and p53 Expressionin Locally Advanced Rectal Cancer / 대한방사선종양학회지

PURPOSE: Cathepsin D (CD) is a lysosomal acid proteinase that is related to malignant progression, invasion, and a poor prognosis in several tumors. The aim of this study was to evaluate the prognostic clinical significance of CD and p53 expression in pretreatment biopsy specimens from patients with locally advanced rectal cancer who were treated with preoperative chemoradiation. MATERIALS AND METHODS: Eighty-nine patients with locally advanced rectal cancer (cT3/T4 or N+) were included in this study. Preoperative chemoradiation consisted of a dose of 50.4 Gy of pelvic radiation and two concurrent cycles of administration of 5-fluorouracil and leucovorin. Surgery was performed six weeks after chemoradiation. CD and p53 expression in pretreatment formalin-fixed paraffin-embedded tumor biopsy specimens were assessed by immunohistochemical staining using a CD and p53 monoclonal antibodies. The threshold value for a positive stain in tumor tissue and stromal cells was 1+ intensity in 10% of the tumors or stromal cells, respectively. RESULTS: Positive CD expression was found in 57 (64%) of the tumors and 32 (35%) of the stromal cell specimens. There was no association with CD expression of the tumor or stromal cells and patient characteristics. There was a correlation between tumor CD expression with stromal cell CD expression (p=0.01). Overexpression of p53 was not a significant prognostic factor. The 5-year overall survival (OS) and disease-free survival (DFS) rates were not different between tumor CD-negative and positive patient biopsy samples (69% vs. 65%, 60% vs. 61%, respectively). The 5-year OS rates in the tumor-negative/stromal cell-negative, tumor-negative/stromal cell-positive, tumor-positive/stromal cell-negative and tumor-positive/ stromal cell-positive biopsy samples were 75%, 28%, 62%, and 73%, respectively. Stromal cell staining only without positive tumor staining demonstrated the worst overall survival prognosis for patients (p=0.013). CONCLUSION: Overexpression of p53 in rectal biopy tissue was not associated with prognostic significance. In the pretreatment biopsy specimens, an exclusive increase in CD expression in stromal cells without tumor expression was related to poor overall survival in patients with locally advanced rectal cancer treated with preoperative chemoradiation.

Effect of Transverse Magnetic Field on Dose Distribution of High Energy Electron Beam / 의학물리

In this work we have measured the dose distribution and the percent depth dose of 20 MeV electron beam using the X-OMAT films in order to verify the effects of transverse magnetic field on high energy elecrtron beam in a phantom. The result shows about 30% increase of the percent depth dose at 4.5 cm depth under the transverse magnetic field of 1.5 Tesla at 7.5 cm depth. We have verified that these were in an agreement with other theoretical results.

Comparison of the Efficacy of Oral Capecitabine versus Bolus 5-FU in Preoperative Radiotherapy of Locally Advanced Rectal Cancer

The effects of treatment with oral capecitabine vs. bolus 5-FU, administered concurrently with preoperative radiotherapy, were compared in the treatment of locally advanced rectal cancer (LARC). One hundred and twenty-seven patients with LARC received concurrent preoperative chemoradiation using two cycles bolus 5-FU (500 mg/m2/day) plus leucovorin (LV, 20 mg/m2/day) (Group I). Another LARC group received concurrent chemoradiation using two cycles 1,650 mg/m2/day of oral capecitabine and 20 mg/m2/day of LV (Group II, 97 patients). Radiation was delivered to the primary tumor at 50.4 Gy in both groups. Definitive surgery was performed 6 weeks after the completion of chemoradiation. A pathologic complete remission was achieved in 11.4% of patients in Group I and in 22.2% of patients in Group II (p= 0.042). The down-staging rates of the primary tumor and lymph nodes were 39.0/ 68.7% in Group I and 61.1/87.5% in Group II (p=0.002/0.005). Sphincter-preserving surgery was possible in 42.1% of patients in Group I and 66.7% of those in Group II (p=0.021). Grade 3 or 4 leucopenia, diarrhea, and radiation dermatitis were statistically more prevalent in Group I than in Group II, while the opposite was true for grade 3 hand-foot syndrome. Preoperative chemoradiation using oral capecitabine was better tolerated than bolus 5-FU and was more effective in the promotion of both down-staging and sphincter preservation in patients with LARC.

Twice Daily Radiation Therapy Plus Concurrent Chemotherapy for Limited-Stage Small Cell Lung Cancer / 대한방사선종양학회지

PURPOSE: A retrospective study was performed to evaluate the efficiency and feasibility of twice daily radiation therapy plus concurrent chemotherapy for limited-stage small cell lung cancer in terms of treatment response, survival, patterns of failure, and acute toxicities. MATERIALS AND METHODS: Between February 1993 and October 2002, 76 patients of histologically proven limited-stage small cell lung cancer (LS-SCLC) were treated with twice daily radiation therapy and concurrent chemotherapy. Male was in 84% (64/76), and median age was 57 years (range, 32~75 years). Thoracic radiation therapy consisted of 120 or 150 cGy per fraction, twice a day at least 6 hours apart, 5 days a week. Median total dose was 50.4 Gy (range, 45~51 Gy). Concurrent chemotherapy consisted of CAV (cytoxan 1000 mg/m2, adriamycin 40 mg/m2, vincristine 1 mg/m2) alternating with PE (cisplatin 60 mg/m2, etoposide 100 mg/m2) or PE alone, every 3 weeks. The median cycle of chemotherapy was six (range, 1~9 cycle). Prophylactic cranial irradiation (PCI) was recommended to the patients who achieved a complete response (CR). PCI scheme was 25 Gy/ 10 fractions. Median follow up was 18 months (range, 1~136 months). RESULTS: Overall response rate was 86%; complete response in 39 (52%) and partial response in 26 (34%) patients. The median overall survival was 23 months. One, two, and three year overall survival rate was 72%, 50% and 30%, respectively. In univariate analysis, the treatment response was revealed as a significant favorable prognostic factor for survival (p<0.001). Grade 3 or worse acute toxicities were leukopenia in 46 (61%), anemia in 5 (6%), thrombocytopenia in 10 (13%), esophagitis in 5 (6%), and pulmonary toxicity in 2 (2%) patients. Of 73 evaluable patients, 40 (55%) patients subsequently had disease progression. The most frequent first site of distant metastasis was brain. CONCLUSION: Twice daily radiation therapy plus concurrent chemotherapy produced favorable response and survival for LS-SCLC patients with tolerable toxicities. To improve the treatment response, which proved as a significant prognostic factor for survival, there should be further investigations about fractionation scheme, chemotherapy regimens and compatible chemoradiotherapy schedule.

Treatment Outcomes of Three-Dimensional Conformal Radiotherapy for Stage III Non-Small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: To evaluate the treatment outcomes of the three-dimensional conformal radiotherapy (3D-CRT), in conjunction with induction chemotherapy, for the treatment of stage III non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Between November 1998 and March 2003, 22 patients with histologically proven, clinical stage III NSCLC, treated with induction chemotherapy, followed by 3D-CRT, were retrospectively analyzed. There were 21 males (96%) and 1 female (4%), with a median age of 68.5 (range, 42~79). The clinical cancer stages were IIIA and IIIB in 41 and 59%, respectively. The histologies were squamous cell carcinoma, adenocarcinoma and others in 73, 18 and 9%, respectively. Twenty patients (91%) received induction chemotherapy before radiation therapy. The majority of the chemotherapy regimen consisted of cisplatin and gemcitabine. Radiation was delivered with conventional anteroposterior/ posteroanterior fields for 36 Gy, and then 3D-CRT was performed. The total radiation dose was 70.2 Gy. The median follow-up period was 17 months (range, 4~59 months). RESULTS: The median overall survival was 19 months. The two and four-year overall survival rates were 37.9 and 30.3%, respectively. The median progression-free survival was 21 months. The two and four-year progression-free survival rates were 42.1 and 21%, respectively. The prognostic factors for overall survival by a univariate analysis were age, histology and T stage (p<0.05). Acute radiation toxicities, as evaluated by the RTOG toxicity criteria, included two cases of grade 3 lung toxicity and one case of grade 2 esophagus toxicity. CONCLUSIONS: The radiation dose could be increased without a significant increment in the acute toxicities when using 3D-CRT. It also seems to be a safe, well- tolerated and effective treatment modality for stage III NSCLC.

Identification of Differentially Expressed Radiation-induced Genes in Cervix Carcinoma Cells Using Suppression Subtractive Hybridization / 대한방사선종양학회지

PURPOSE: A number of genes and their products are induced early or late following exposure of cells to ionizing radiation. These radiation-induced genes have various effects on irradiated cells and tissues. Suppression subtractive hybridization (SSH) based on PCR was used to identify the differentially expressed genes by radiation in cervix carcinoma cells. MATERIASL AND METHODS: Total RNA and poly (A)+ mRNA were isolated from irradiated and non-irradiated HeLa cells. Forward- and reverse-subtracted cDNA libraries were constructed using SSH. Eighty-eight clones of each were used to randomly select differentially expressed genes using reverse Northern blotting (dot blot analysis). Northern blotting was used to verify the screened genes. RESULTS: Of the 176 clones, 10 genes in the forward-subtracted library and 9 genes in the reverse-subtracted library were identified as differentially expressed radiation-induced genes by PCR-select differential screening. Three clones from the forward-subtracted library were confirmed by Northern blotting, and showed increased expression in a dose-dependent manner, including a telomerase catalytic subunit and sodium channel-like protein gene, and an ESTs (expressed sequence tags) gene. CONCLUSION: We identified differentially expressed radiation-induced genes with low-abundance genes with SSH, but further characterization of theses genes are necessary to clarify the biological functions of them.

Detection of RTP801, a Gene That is Differentially Expressed in Irradiated HeLa Cells / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: To quantify the effects of irradiation on the expression levels of a differentially expressed gene, RTP801, in HeLa cells. MATERIALS AND METHODS: Total RNA was isolated from irradiated and non-irradiated HeLa cells. A subtraction library was constructed, from which 88 random clones were screened. The expression patterns of one clone, detected by reverse Northern blotting, were quantified by real time RT-PCR, using CYBR green I dye. RESULTS: RTP801, a hypoxia-inducible factor-I-responsive gene, was identified as a differentially expressed gene in HeLa cells exposed to X-ray. Real time RT-PCR showed that the mRNA levels of RTP801 were greatly diminished by radiation. CONCLUSIONS: These results suggest that down-regulation of hypoxia-inducible factor-I-responsive genes, such as RTP801, in irradiated HeLa cells may result in reductions in the radiotherapy resistance of tumor cells.

Clinical Experience in Conformal Stereotactic Radiotherapy of Irregularly Shaped Intracranial Tumors / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The dosimetric advantages of multiple non-coplanar stationary fields for stereotactic radiotherapy or adiosurgery (SRT/S) are well known. However, this technique is not widely used due to the logistical problems associated with producing and testing customized collimators. We report our experience of SRT/S using multiple non-coplanar stationary fields (conformal SRT/ S). MATERIALS AND METHODS: Between August 1997 and February 2002, we performed frameless SRT/S in 63 patients. We chose conformal SRT/S when the tumor was of a very irregular shape or larger than 4 cm. We obtained three pieces of information: 1) the couch translations required to bring the target point to the isocenter, 2) the distance between the stereotaxic markers in the CT study, and the distance between the markers determined from orthogonal beam films, taken in the anterior- posterior and lateral directions, and 3) the rotational movement of the head position between the CT study and actual treatment position. We evaluated two kinds of data: 1) the precision of the isocenter setup, and 2) the reproducibility of the head position in the a) translational and b) rotational components. RESULTS: Twenty-six of the 63 patients receiving stereotactic treatment received conformal SRT/S. The precision of the isocenter setup for the conformal SRT/S was x=-0.03+/-0.26 mm, y=0.19+/-0.25 mm and z=-0.20+/-0.27 mm. The reproducibilities of the head position with the conformal SRT/S were 0.5 mm and less than 1degrees C, for the translational and rotational components, in any plane. CONCLUSION: We were able to apply conformal stereotactic irradiation, which has a dosimetric advantage, to irregularly shaped intracranial tumors, with precision and reproducibility of head position for the isocenter setup nearly equivalent to that of frame-based SRS or multiple-arc SRT/S.

Primary Malignant Melanoma of the Vagina: A Case Report / 대한방사선종양학회지

A primary malignant melanoma of the vagina is a very rare gynecological malignant tumor. Its clinical behavior is more aggressive than that of cutaneous and vulvar melanomas. We present a case of a large sized primary melanoma of the lower third of the vagina, with a cervical lesion, in a 58-year-old postmenopausal woman. The patient was treated with conventional external radiation therapy and intracavitary radiotherapy (ICR), without surgical treatment. Although the primary lesion showed a partial response, the patient died of extensive metastases, which were found 4.5 months after the initial diagnosis. We suggest that shortening the treatment period, such as hypofractionated radiation therapy and surgical removal, and various systemic therapies for preventing early distant metastasis, are appropriate treatments for a primary malignant melanoma of the vagina, with a large tumor size.

Investigation of Study Items for the Patterns of Care Study in the Radiotherapy of Laryngeal Cancer: Preliminary Results / 대한방사선종양학회지

PURPOSE: In order to develop the national guide-lines for the standardization of radiotherapy we are planning to establish a web-based, on-line data-base system for laryngeal cancer. As a first step this study was performed to accumulate the basic clinical information of laryngeal cancer and to determine the items needed for the data-base system. MATERIALS AND METHODS: We analyzed the clinical data of patients who were treated under the diagnosis of laryngeal cancer from January 1998 through December 1999 in the South-west area of Korea. Eligibility criteria of the patients are as follows: 18 years or older, currently diagnosed with primary epithelial carcinoma of larynx, and no history of previous treatments for another cancers and the other laryngeal diseases. The items were developed and filled out by radiation oncologist who are members of Korean Southwest Radiation Oncology Group. SPSS v10.0 software was used for statistical analysis. RESULTS: Data of forty-five patients were collected. Age distribution of patients ranged from 28 to 88 years (median, 61). Laryngeal cancer occurred predominantly in males (10:1 sex ratio). Twenty-eight patients (62%) had primary cancers in the glottis and 17 (38%) in the supraglottis. Most of them were diagnosed pathologically as squamous cell carcinoma (44/45, 98%). Twenty-four of 28 glottic cancer patients (86%) had AJCC (American Joint Committee on Cancer) stage I/II, but 50% (8/16) had in supraglottic cancer patients (p=0.02). Most patients (89%) had the symptom of hoarseness. Indirect laryngoscopy was done in all patients and direct laryngoscopy was performed in 43 (98%) patients. Twenty-one of 28 (75%) glottic cancer cases and 6 of 17 (35%) supraglottic cancer cases were treated with radiation alone, respectively. The combined treatment of surgery and radiation was used in 5 (18%) glottic and 8 (47%) supraglottic patients. Chemotherapy and radiation was used in 2 (7%) glottic and 3 (18%) supraglottic patients. There was no statistically significant difference in the use of combined modality treatments between glottic and supraglottic cancers (p=0.20). In all patients, 6 MV X-ray was used with conventional fractionation. The fraction size was 2 Gy in 80% of glottic cancer patients compared with 1.8 Gy in 59% of the patients with supraglottic cancers. The mean total dose delivered to primary lesions were 65.98 Gy and 70.15 Gy in glottic and supraglottic patients treated, respectively, with radiation alone. Based on the collected data, 12 modules with 90 items were developed for the study of the patterns of care in laryngeal cancer. CONCLUSION: The study items for laryngeal cancer were developed. In the near future, a web system will be established based on the items investigated, and then a nation-wide analysis on laryngeal cancer will be processed for the standardization and optimization of radiotherapy.

Fractionated Stereotactic Radiotherapy for Metastatic Brain Tumor in Non-Small Cell Lung Cancer

PURPOSE: To evaluate the results of treatment with fractionated stereotactic radiotherapy for metastatic brain tumors in non-small cell lung cancer. MATERIALS AND METHODS: Between August 1997 and August 2001, 17 patients, with metastatic brain tumors in non-small cell lung cancer (26 lesions), completed frameless fractionated stereotactic radiotherapy. All patients received a 30~36 Gy/10~20 fx external beam irradiation to the whole brain. Twelve received fractionated stereotactic radiotherapy for a single lesion, 3 for 2 lesions and 1 each for 3 and 5 lesions. The median tumor volume was 1.7 cc (0.3~55.2 cc). The fractionation schedule for the fractionated stereotactic radiotherapy was 21 Gy/3 fx in 8 lesions, 25 Gy/5 fx in 7, 18 Gy/1 fx in 6, 30 Gy/5 fx in 4 and 15 Gy/5 fx in 1. Multiple-arc, and 3D conformal, fractionated stereotactic radiotherapy, were delivered to 24 and 2 lesions, respectively. Follow-up was possible in all patients. RESULTS: Nine out of 13 patients with follow-up radiological evaluations achieved a complete response (CR). The overall median survival, and 1 and 2 year survival rates were 20 months, and 64 and 28%, respectively. The median survival, and the 1 and 2 year survival rate of CR group were 20 months, and 73 and 22%, respectively. No patient has experienced any acute side reactions or late complications from the fractionated stereotactic radiotherapy. CONCLUSION: Although the number of patients treated with fractionated stereotactic radiotherapy was small, and follow-up period short, this study suggests that external beam irradiation to the whole brain, with 30 Gy/10 fx followed by fractionated stereotactic radiotherapy, could be a good treatment option for patients with metastatic brain tumors in non-small cell lung cancer.

Radiation Enhancement by The Combined Use of CPT-11 and Etoposide in Human Lung Cancer Cells

PURPOSE: To evaluate the radiation enhancement by a combination of CPT-11 and etoposide, with in vitro ionizing radiation. MATERIALS AND METHODS: H460 human lung carcinoma cells were plated, and treated with 4.5 microM CPT-11 for 4 hr, then irradiated with various doses of radiation, and treated with 1microM etoposide for 1.5 hr. The survival and sublethal damage recovery (SLDR) were determined by a clonogenic assay. The analysis of apoptosis, due to the combined treatment with drugs and radiation, was performed using 7-AAD staining and flow cytometry. RESULTS: The survival experiments resulted in radiation dose enhancement ratios (DER) of 1.30, 1.39, and 1.65 for CPT-11, etoposide, and CPT-11 plus etoposide, respectively. The analysis of apoptosis, using 7-AAD staining and flow cytometry, indicated an synergistic effect. Inhibition of the SLDR was not observed with the CPT-11 plus etoposide. CONCLUSION: These data show that the combination of CPT-11 and etoposide is a more effective radiation enhancer in human lung cancer cells than either agent used individually in human lung cancer cells. This radiation enhancement is not caused by the inhibition of the SLDR, but other mechanisms may be involved in the combined treatment of CPT-11 and etoposide combined treatment.

The Role of Air-Vacuum Cushion Device in Patients with Rectal Cancer in Radiation Therapy / 대한방사선종양학회지

PURPOSE: We analyzed setup errors induced by using air-vacuum cushion as immobilization device in patients with rectal cancer. MATERIALS AND METHODS: We had treated the twenty patients with rectal cancer by 6 MV, 10 MVx-ray from Aug. 1998 to Aug. 1999 at Chungnam National University Hospital. All patients were treated at prone position. They were separated to two groups, control group, 10 patients using styrofoam, and test group, 10 patients using styrofoam and air-vacuum cushion. We measured errors of posterior field forx, y axis and lateral field for z, y axis with simulation film and EPID image using a matching technique. RESULTS: In control group, the mean displacement values of pelvic bone landmark forx axis and y axis were 0.02 mm. 0.78 mm, respectively and the standard deviations of systematic error were 2.13 mm, 2.40 mm, respectively and the standard deviation of random error were 1.46 mm. 1.51 mm, respectively. In test group, the mean displacement values ofx axis and y axis were -0.33 mm. 0.81 mm, respectively and the standard deviations of systematic error were 1.71 mm, 3.08 mm, respectively and the standard deviations of random errors were 1.40 mm. 1.88 mm, respectively. The mean displacement values of z axis and y axis were 2.98 mm. 0.74 mm, respectively and the standard deviations of systematic error were 4.75 mm, 2.65 mm, respectively and standard deviations of random error were 2.69 mm. 1.86 mm, respectively. The statistical difference of field size by using air vacuum cushion between two groups in posterior direction and lateral direction was not shown. CONCLUSION: We think that use of air-vacuum cushion may not be an advantage for improving setup accuracy in rectal cancer patients.

The Change of Tumor Interstitial Fluid Pressure Affected by Radiation Therapy in Patients with Uterine Cervix Cancer / 대한암학회지

No abstract available.