• Radiation Oncology Journal
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• v.16 no.4
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• pp.389-398
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• 1998

Purpose : To evaluate the role of conventional postoperative adjuvant radiotherapy in the management of supratentorial malignant glioma and to determine favorable prognostic factors affecting survival. Materials and Methods : From Sep. 1985 to Mar. 1997, the number of eligible patients who received postoperative radiotherapy completely was 69. They ranged in age from 7 to 66 years (median, 47). Forty-two (61$\%$) patients were glioblastoma multiforme and the other 27 (39$\%$) were anaplastic astrocytoma. Twenty patients (29$\%$) had Karnofsky score equal or more than 80 preoperatively. Forty-three patients (62$\%$) had symptom duration equal or less than 3 months. Twenty-four patients (35$\%$) had gross total resection and forty patients(58$\%$) had partial resection, the remaining five patients (7$\%$) had biopsy only. Radiotherapy dose ranged from 50.4 Gy to 61.2 Gy (median, 55.8; mode, 59.4) with fraction size of 1 8 Gy-2.0 Gy for 33-83 days(median, 48) except three patients delivered 33, 36, 39 Gr, respectively with fraction size of 3.0 Gy due to poor postoperative performance status. Follow-up rate was 93$\%$ and median follow-up period was 14 months. Results : Overall survival rate at 2 and 3 years and median survival were 38$\%$, 20$\%$, and 16 months for entire patients; 67$\%$, 44$\%$, and 34 months for anaplastic astrocytoma; 18$\%$, 4$\%$, and 14 months for glioblastoma multiforme, respectively (p=0.0001). According to the extent of surgery, 3-year overall survival for gross total resection, partial resection, and biopsy only was 38$\%$, 11$\%$, and 0$\%$, respectively (p=0.02) The 3-year overall survival rates for patients age 40>, 40-59, and 60< were 52$\%$, 8$\%$, and 0$\%$, respectively (p=0.0007). For the variate of performance score 80< vs 80>, the 3-year survival rates were 53$\%$ and 9$\%$, respectively (p=0.008). On multivariate analysis including covariates of three surgical and age subgroups as above, pathology, extent of surgery and age were significant prognostic factors affecting overall survival. On another multivariate analysis with covariates of two surgical (total resection vs others) and two a9e (50> vs 50<) subgroups, then, pathology, extent of surgery and performance status were significant factors instead of age and 3-year cumulative survival rate for the five patients with these three favorable factors was 100$\%$ without serious sequela. Conclusion : We confirmed the role of postoperative conventional radiotherapy in the management of supratentorial malignant glioma by improving survival as compared with historical data of surgery only. Patients with anaplastic astrocytoma, good performance score, gross total resection and/or young age survived longest. Maximum surgical resection with acceptable preservation of neurologic function should be attempted in glioblastoma patients, especially in younger patients. But the survival of most globlastoma patients without favorable factors is still poor, so other active adjuvant treatment modalities should be tried or added rather than conventional radiation treatment alone in this subgroup.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.813-818
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• 2014

Aims: To describe our institutional experience with high dose rate (HDR) interstitial brachytherapy (IBT) compared with previously reported results on the low dose rate (LDR) practice for head and neck cancer. Materials and Methods: Eighty-four patients with oral cavity (n=70) or oropharyngeal cancer (n=14) were treated with 192Ir HDR-IBT. Seventy-eight patients had stage I or II tumour. The patients treated with IBT alone (n=42) received 39-42 Gy/10-14 fractions (median=40 Gy/10 fractions). With respect to the combination therapy group (n=42), prescription dose comprised of 12-18 Gy/3-6 fractions (median=15 Gy/5 fractions) for IBT and 40-50 Gy/20-25 fractions (median=50 Gy/25 fractions) for external radiotherapy. Brachytherapy was given as 2 fractions per day 6 hours apart with 4 Gy per fraction for monotherapy and 3 Gy per fraction for combination therapy. Results: Four patients were not evaluable in the analysis of outcome. The primary site relapse rates were 23.8% (10/42) and 68.4% (26/38) in patients treated with IBT alone and combination therapy, respectively (p<0.001). Salvage surgery was performed in 19 patients. The 5-year local control rate was estimated at 62% and the disease-free survival (DFS) rate at 52% for all patients. Local control with respect to T1 and T2 tumours was 84% and 42%, respectively. Conclusions: Our present series on HDR-IBT and the previous report on LDR-IBT for head and neck cancer demonstrated similar DFS rates at 5 years (52%). The rate of regional failure in node-negative patients was <20% in both of our series. HDR-IBT offers similar results to LDR-IBT for head and neck cancer.

• Korean Journal of Head & Neck Oncology
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• v.19 no.1
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• pp.34-40
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• 2003

Objective: To analyze the treatment-related parameters after the radiotherapy of T1N0 squamous cell carcinoma of the glottic larynx. Materials and Methods: Between October 1989 and August 2000, 54 patients with histologically proven T1N0 squamous cell carcinoma of the glottic larynx who received definitive radiation therapy in Department of Radiation Oncology, Asan Medical Center were analyzed. They were all males with age ranged from 31 to 80 years (median 61 years). 1997 AJCC stages were 31 T1a, 23 T1b. Patients were treated with 4-MV X-rays with a parallel-opposed two-field technique. Ten patients received 66.0-68.4Gy at 1.2Gy per fraction twice daily, 21 patients received 64.8-66.6Gy at 1.8Gy per fraction once daily, and 23 patients received 66.0Gy at 2.0Gy per fraction once daily. Follow-up period was 16-119 months (median 56 months). Results: 5-year overall survival and local control rates for patients with T1 lesions were 87.0% and 88.5%, respectively. 5-year local control with larynx preservation rate was 90.5%. Host and tumor-related prognostic factors including age, stage, anterior commissure involvement and tumor bulk proved not to be significant. Only shorter overall treatment time among treatment-related factors had correlation with imporved local control. Conclusion: Comparable high local control rate with organ preservation was achieved with primary radiation therapy and salvage surgery. Shortening of overall treatment time is related to improved local control rate. To determine the optimal fractionation scheme, randomized trial is mandatory.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.165-173
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• 1994

Purpose : Metastatic cancer to the brain is a major problem for the patients with bronchogenic carcinoma, and most of these patients have a limited survival expectancy. To increase tumor control and / or to decrease late morbidity with possible shortening in over-all treatment period, multiple daily fraction technique for brain metastasis was performed. The author reperesented the results of accelerated fractionation radiotherapy in patients with brain metastases from non-small cell lung cancer. Materals and Methods : Twenty-six patients with brain metastases from non-small cell lung cancer between 1991 and 1993 received brain radiotherapy with a total dose of 48 Gy, at 2 Gy per fraction, twice a day with a interfractional period of 6 hours, and delivered 5 days a week. The whole brain was treated to 40 Gy and boost dose escalated to 8 Gy for single metastatic lesion by reduced field. Twenty-four of the 26 patients completed the radiotherapy. Radiotherapy was interupted in two patients suggesting progressive intracerebral diseases. Results : This radiotherapy regimen appears to be comparable to the conventional scheme in relief from symptoms. Three of the 24 patients experienced nausea and or vomiting during the course of treatment because of acute irradiation toxicity. The author observed no excessive toxicity with escalating dose of irradiation. An increment in median survival, although not statistically significant(p>0.05), was noted with escalating doses(48 Gy) of accelerated fractionation(7 months) compared to conventional treatment(4.5 months). Median survival also increased in patients with brain solitary metastasis(9 months) compared to multiple extrathoracic sites(4 months), and in patients with good performance status(9 months versus 3.5 months), they were statistically significant (p<0.01). Conclusion : The increment in survival in patients with good prognostic factors such as controlled primary lesion, metastasis in brain only and good perfomance status appeared encouraging. Based on these results, a multi-institutional prospective randomized trial should be initiated to compare the twice-a-day and once-a-day radiotherapy schemes on patients with brain metastasis with careful consideration for the patients' quality of life.

• Radiation Oncology Journal
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• v.19 no.4
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• pp.312-318
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• 2001

Purpose : To assess the locoregional recurrence rate, survival rate and prognostic factors after modified radical mastectomy and postoperative adjuvant radiation therapy with or with chemotherapy in high-risk breast cancer patients. Methods : Between $1984\~1995$, 48 patients underwent postoperative irradiation to the regional lymphatics and chest wall due to large tumor size $(\geq5\;cm)$ or small tumor size (<5 cm) with axillary lymph node involvement after modified radical mastectomy. The median age of the patients was 47 years (range, $31\~79\;years$). The clinical tumor size was <2 cm in 1 patient, $2\~5\;cm$ in 15 patients, and >5 cm in 32 patients. Thirty two patients had positive axillary lymph nodes. Forty two patients were irradiated to the chest wall and regional lymph node and 6 patients were irradiated in the chest wall only. Radiation dose to the chest wall and regional lymph node was 5040 cGy/28 fraction. The median follow-up time was 61 months. Results : Locoregional recurrence rate was $8\%$ and distant metastatic rate was $14\%$. The actuarial overall survival rate and disease-free survival rate was $53\%\;and\;62\%$ at 5 years, respectively. The median survival time was 57 months. Five-year overall survival rate by the stage is $70\%$ in IIB and $58\%$ in IIA. The significant prognostic factor for survival on multivariate analysis was the stage. Conclusion : Postoperative adjuvant radiation therapy in high-risk breast cancer can reduce the locoregional recurrence rate and increase the survival time by combined chemotherapy. The significant prognostic factor for survival rate was the stage.

• Radiation Oncology Journal
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• v.21 no.2
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• pp.112-117
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• 2003

Purpose: The effects of hypefractionation radiation therapy, such as the failure pattern and survival, on the treatment results in advanced stage head and neck cancer were studied. Materials and Methods: Between September 1990 and October 1998, 24 patients with advanced stage (III, IV) head and neck cancers, were treated using hyperfractionation radiation therapy in the Department of Radiation Oncology at the Keimyung University Dongsan Medical Center. The male to female ratio was 7 : 1, and the age range from 38 to 71 years with the median of 56 years. With regard to the TNM stage, 11 patients were stage III and 13 were stage IV. The sites of primary cancer were the nasopharynx in six, the hypopharynx in 6, the larynx in five, the oropharynx in three, the maxillary sinus in three, and the oral cavity in one patient. The radiotherapy was delivered by 6 MV X-ray, with a fraction size of 1.2 Gy at two fractions a day, with at least 6 hours inter-fractional interval. The mean total radiation doses was 72 Gy, (ranging from 64.4 to 75.8 Gy). Follow-up periods ranged between 3 and 136 months, with the median of 52 months. Results: The overall survival rates at 3 and 5 years in all patients were 66.7$\%$, and 52.4$\%$. The disease-free survival rates at 3 and S years (3YDFS, 5YDFS) in all patients were 66.7$\%$ and 47.6$\%$. The 3YDFS and 5YDFS in stage III patients were 81.8$\%$ and 63.6$\%$, and those in stage IV patients were 53.8$\%$ and 32.3$\%$. Ten patients were alive with no local nor distant failures at the time of analyses. Six patients (25$\%$) died due to distant metastasis and 12.5$\%$ died due to local failure. Distant metastasis was the major cause of failure, but 2 patients died due to unknown failures and 3 of other diseases. The distant metastasis sites were the lung (3 patients), the bone (1 patient), and the liver (2 patients). One patient died of second esophageal cancer. There were no severe late complications, with the exception of 1 osteo-radionecrosis of the mandible 58 months after treatment. Conclusion: Although this study was peformed on small patients group, we considered hypefractionated radiation therapy for the treatment of advanced stage head and neck cancer might improve the disease free survival and decrease the local failure with no increase in late complications despite of the slight Increase in acute complications.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1677-1680
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• 2013

Background: Areas of Iran have among the highest incidences of esophageal cancer in the world. Definitive chemo-radiotherapy (DCRT) is used for locally advanced esophageal cancer and for inoperable tumors asan alternative to surgical treatment. Materials and Methods: This retrospective study was conducted in North-West Iran 2006-2011, including 267 consecutive patients with non-metastatic esophageal cancer. Eligible inoperable patients were treated with DCRT or definitive radiotherapy (DRT) alone. Radiotherapy (RT) was delivered at 1.8-2 Gy/day for five consecutive days in a given week. Chemotherapy (CT) consisted of cisplatin and 5-fluorouracil. Results: The median survival was 12.7 months with 1, 3 and 5 year survival rates of 55%, 18% and 11%, respectively. On univariate analysis, relations with age at diagnosis (p=0.015), N-stage (p=0.04), total dose of RT (p=0.001), fraction (p<0.001), Gap status (p=0.025), chemotherapeutic regimens (P=0.027), and 5-Fu $Mg/m^2$ (P=0.004) were apparent. Comparing DCRT to DRT, there was a significant difference in survival. Multivariate analysis was performed for comparison between DCRT and DRT showed significant association with age group ${\geq}65$ to <65 (P=0.02; OR: 1.46), the total RT dose (Gy) ${\geq}50$ to <50 (P=0.01; OR: 0.65) and the fraction group ${\geq}25$ to <25 (P=<0.001; OR: 0.54). Conclusions: The survival rates of esophageal cancer treated with DCRT in North West of Iran is poor; therefore, early detection and improved treatment methods, with clinical trials are a high priority.

• Radiation Oncology Journal
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• v.37 no.4
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• pp.293-301
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• 2019

Purpose: External beam radiotherapy (EBRT) is a useful option to treat head and neck skin cancer patients who are not indicated for surgery. In this study, we evaluated the treatment outcomes of EBRT in an Asian population. Materials and Methods: The records from 19 head and neck skin cancer patients (10 with squamous cell carcinoma and 9 with basal cell carcinoma) who were treated with definitive or adjuvant EBRT from 2009 to 2017 were retrospectively reviewed. The radiotherapy doses administered ranged from 50 to 66 Gy (median, 55 Gy) with 2.0-2.75 Gy per daily fraction (median, 2.5 Gy). The T stage at presentation was as follows: Tis (1 patient), T1 (11 patients), T2 (6 patients), and T3 (1 patient). None had regional lymph node disease or distant metastasis at presentation. The local failure-free survival (LFFS) rates, toxicity, and cosmetic results were analyzed. Results: The median age was 75.5 years (range, 52.6 to 92.5 years). The median follow-up duration from the completion of radiotherapy was 44.9 months (range, 5.8 to 82.6 months). One local failure occurred in a patient with a 2.1-cm posterior neck squamous cell carcinoma at 32.5 months after radiotherapy (1/19, 5.3%). The 3-year LFFS rate was 91.7%. No patients died from skin cancer during follow-up, and no grade 3 complications occurred. The cosmetic outcomes were excellent for 16 (84.2%) and good for 3 (15.8%) of the 19 patients. Conclusion: EBRT offers good local control and cosmetic outcomes in patients with head and neck skin cancer, with no grade 3 complications.

• Radiation Oncology Journal
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• v.22 no.4
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• pp.237-246
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• 2004

Purpose: To investigate the effects of radiation dose-escalation on the treatment outcome, complications and the other prognostic variables for glioblastoma patients treated with 3D-conformal radiotherapy (3D-CRT). Materials and Methods: Between Jan 1997 and July 2002, a total of 75 patients with histologically proven diagnosis of glioblastoma were analyzed. The patients who had a Karnofsky Performance Score (KPS) of 60 or higher, and received at least 50 Gy of radiation to the tumor bed were eligible. All the patients were divided into two arms; Arm 1, the high-dose group was enrolled prospectively, and Arm 2, the low-dose group served as a retrospective control. Arm 1 patients received $63\~70$ Gy (Median 66 Gy, fraction size $1.8\~2$ Gy) with 3D-conformal radiotherapy, and Arm 2 received 59.4 Gy or less (Median 59.4 Gy, fraction size 1.8 Gy) with 2D-conventional radiotherapy. The Gross Tumor Volume (GTV) was defined by the surgical margin and the residual gross tumor on a contrast enhanced MRI. Surrounding edema was not included in the Clinical Target Volume (CTV) in Arm 1, so as to reduce the risk of late radiation associated complications; whereas as in Arm 2 it was included. The overall survival and progression free survival times were calculated from the date of surgery using the Kaplan-Meier method. The time to progression was measured with serial neurologic examinations and MRI or CT scans after RT completion. Acute and late toxicities were evaluated using the Radiation Therapy Oncology Group neurotoxicity scores. Results: During the relatively short follow up period of 14 months, the median overall survival and progression free survival times were $15{\pm}1.65$ and $11{\pm}0.95$ months, respectively. The was a significantly longer survival time for the Arm 1 patients compared to those in Arm 2 (p=0.028). For Arm 1 patients, the median survival and progression free survival times were $21{\pm}5.03$ and $12{\pm}1.59$ months, respectively, while for Arm 2 patients they were $14{\pm}0.94$ and $10{\pm}1.63$ months, respectively. Especially in terms of the 2-year survival rate, the high-dose group showed a much better survival time than the low-dose group; $44.7\%$ versus $19.2\%$. Upon univariate analyses, age, performance status, location of tumor, extent of surgery, tumor volume and radiation dose group were significant factors for survival. Multivariate analyses confirmed that the impact of radiation dose on survival was independent of age, performance status, extent of surgery and target volume. During the follow-up period, complications related directly with radiation, such as radionecrosis, has not been identified. Conclusion: Using 3D-conformal radiotherapy, which is able to reduce the radiation dose to normal tissues compared to 2D-conventional treatment, up to 70 Gy of radiation could be delivered to the GTV without significant toxicity. As an approach to intensify local treatment, the radiation dose escalation through 3D-CRT can be expected to increase the overall and progression free survival times for patients with glioblastomas.

• Radiation Oncology Journal
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• v.6 no.1
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• pp.1-11
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• 1988

Recovery from potentially lethal damage (PLDR) after irradiation was studied in plateau-phase culture of Vero cells in vitro. Unfed plateau-phase cells were irradiated with dose of 1 to 9Gy using Cs-137 irradiator. Cells then were incubated again and left in situ for 0, 1, 2, 3, 4, 5, 6, and 24 hours and then were trypsinized explanted, and subcultured in fresh RPMI-1640 media containing $0.33\%$ agar. Cell survival was measured by colony forming ability. An adequate number of heavily irradiated Vero cells were added as feeder cells to make the total cell number constant in every culture dish. As the postirradiation in situ incubation time increased, surviving fraction increased by PLDR. The rate of PLDR was so rapid that increased surviving fraction reached saturation level at 2 to 4 hours after in situ incubation. As the radiation dose increased, the rate of PLDR fastened and the magnitude of increased surviving fraction at saturation level by PLOR also increased. In analysis of cell survival curve fitted to the linear-quadratic model, the linear inactivation coefficient $(\alpha)$ decreased largely and reached nearly to zero but the quadratic inactivation coefficient $(\beta)$ increased minimally by increment of postirradiation in situ incubation time. So PLDR mainly affected the damage expressed as $\alpha$, In the multitarget model, significant change was not obtained in $D_0\;but\;in D_q$. Therefore, shoulder region in cell survival curve was mainly affected by PLDR and terminal slope was not influenced at all. And dose-modifying factor by PLDR was relatively higher in shoulder region, that is, in low dose area below 3 Gy.