• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2613-2617
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• 2015

Radiation induced lung injury has long been considered a treatment limiting factor for patients requiring thoracic radiation. This radiation induced lung injury happens early as well as late. Radiation induced lung injury can occur in two phases viz. early (< 6 months) when it is called radiation pneumonitis and late (>6 months) when it is called radiation induced lung fibrosis. There are multiple factors that can be patient, disease or treatment related that predict the incidence and severity of radiation pneumonitis. Radiation induced damage to the type I pneumocytes is the triggering factor to initiate such reactions. Over the years, radiation therapy has witnessed a paradigm shift in radiation planning and delivery and successfully reduced the incidence of lung injury. Radiation pneumonitis is usually a diagnosis of exclusion. Steroids, ACE inhibitors and pentoxyphylline constitute the cornerstone of therapy. Radiation induced lung fibrosis is another challenging aspect. The pathophysiology of radiation fibrosis includes continuing inflammation and microvascular changes due to pro-angiogenic and profibrogenic stimuli resembling those in adult bronchiectasis. General supportive management, mobilization of airway secretions, anti-inflammatory therapy and management of acute exacerbations remains the treatment option. Radiation induced lung injury is an inevitable accompaniment of thoracic radiation.

• Journal of Korean Neurosurgical Society
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• 제42권3호
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• pp.200-204
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• 2007

Objective : Radiation therapy is an important treatment for brain tumor. However, serious complications such as radiation necrosis can occur and it may be secondary to the expression of acute phase genes, like cytokines. In particular, inflammatory cytokines (IL-$1{\beta}$, TNF-${\alpha}$) and other immunomodulatory cytokines (TNF-${\alpha}$, TGF-${\beta}1$) might be changed after irradiation (high single dose irradiation). Although it has been reported that IL-1 level is remarkably elevated within 8 week after the irradiation to the rat brain. the change of cytokines levels at acute phase (within 24 hours) has not been reported. In the present study, we examined TNF-${\alpha}$, TGF-${\beta}1$, and IL-$1{\beta}$ levels in acute phase to clarify the early effect of cytokines on the radiation-induced brain damage. Methods : Fifty Sprague-Dawley rats were used and these were divided into irradiation group and control group. After a burr-hole trephination on the right parietal area using a drill, a single 10Gy was irradiated at the trephined site. Their forebrains were extirpated at 30 min, 2 hr, 8 hr, 12 hr and 24 hr, respectively and examined for the expression of TNF-${\alpha}$, TGF-${\beta}1$, and IL-$1{\beta}$. Results : The expression of TNF-${\alpha}$ and TGF-${\beta}1$ were decreased until 12 hr after irradiation but elevated thereafter. The expression of IL-1 was peak at 8 hr and then decreased until 12 hr but elevated after this time window. The present study indicated that expression of cytokines (TNF-${\alpha}$, TGF-${\beta}1$ and IL-$1{\beta}$) were increased at 24 hr after the irradiation to the rat brain. IL-$1{\beta}$ level, on the other hand. reached peak at 8 hr after radiation injury. Conclusion : These findings indicate that IL-1, among various cytokines, may have a more important role in the inflammatory reaction by radiation injury at acute phase and provide some clues for better understanding of the pathogenesis of radiation injury.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4711-4715
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• 2013

Aim: The aim of this study was to evaluate acute adverse events and efficacy of three-dimensional intensitymodulated radiotherapy (IMRT) combined with endocrine therapy for intermediate and advanced prostate cancer. Methods: Sixty-seven patients were treated with three-dimensional IMRT combined with maximum androgen blockade. The correlation between radiation-induced rectal injury and clinical factors was further analyzed. Results: After treatment, 21 patients had complete remission (CR), 37 had partial remission (PR), and nine had stable disease (SD), with an overall response rate of 86.5%. The follow-up period ranged from 12.5 to 99.6 months. Thirty-nine patients had a follow-up time of ${\geq}$ five years. In this group, three-year and five-year overall survival rates were 89% and 89.5%, respectively; three-year and five-year progression-free survival rates were 72% and 63%. In univariate analyses, gross tumor volume was found to be prognostic for survival ($X^2$ = 5.70, P = 0.037). Rates of leucopenia and anemia were 91.1% and 89.5%, respectively. Two patients developed acute liver injury, and a majority of patients developed acute radiation proctitis and cystitis, mainly grade 1/2. Tumor volume before treatment was the only prognostic factor influencing the severity of acute radiation proctitis (P < 0.05). Conclusions: IMRT combined with endocrine therapy demonstrated promising efficacy and was well tolerated in patients with intermediate and advanced prostate cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7569-7576
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• 2013

Background: The purpose of this article is to present preliminary results of simultaneous boost irradiation radiotherapy for locally advanced nasopharyngeal carcinoma (NPC). Methods: Fifty-eight patients who underwent simultaneous boost irradiation radiotherapy for NPC in Cancer Center of Sun Yat-sen University between September 2004 and December 2009 were eligible. Acute and late toxicities were scored weekly according to the Radiation Therapy Oncology Group (RTOG) acute and late radiation morbidity scoring schemes. An especial focus was on evidence of post-radiation brain injury. Also quality of life was analysed according to the EORTC (European Organisation for Research and Treatment of Cancer) recommendations. Discrete variables were compared by ${\chi}^2$ test. The Kaplan-Meier method was used to calculate the survival rates and generate survival curves. Results: A total of 58 patients with a mean follow-up time of 36 months completed clinical trials.Fifty-seven patients (98.3) achieved complete remission in the primary sites and cervical lymph nodes, with only one patient (1.7%) showing partial remission.The most frequently observed acute toxicities during the concurrent chemoradiotherapy were mucositis and leucopenia. Four patients (6.9%) had RTOG grade 3 mucositis, whereas four patients (6.9%) had grade 3 leucopenia. No patient had grade 4 acute toxicity. Three (5.17%) of the patients exhibited injury to the brain on routine MRI examination, with a median observation of 32 months (range, 25-42months). All of them were RTOG grade 0. The 3-year overall, regional-free and distant metastasis-free survival rates were 85%, 94% and 91%, respectively. Conclusion: Simultaneous boost irradiation radiotherapy is feasible in patients with locally advanced nasopharyngeal carcinoma. The results showed excellent local control and overall survival, with no significant increase the incidence of radiation brain injury or the extent of damage. A larger population of patients and a longer follow-up period are needed to evaluate ultimate tumor control and late toxicity.

• Nuclear Engineering and Technology
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• 제38권3호
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• pp.231-238
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• 2006

Whole-body exposure to high-dose radiation causes injury involving multiple organs that depends on their sensitivity to radiation. This acute radiation syndrome (ARS) is caused by a brief exposure of a major part of the body to radiation at a relatively high dose rate. ARS is characterized by an initial prodromal stage, a latent symptom-free period, a critical or manifestation phase that usually takes one of four forms (three forms): hematologic, gastrointestinal, or cardiovascular and neurological (neurovascular), depending upon the exposure dose, and a recovery phase or death. One of the most important factors in treating victims exposed to radiation is the estimation of the exposure dose. When high-dose exposure is considered, initial dose estimation must be performed in order to make strategy decisions for treatment as soon as possible. Dose estimation can be based on onset and severity of prodromal symptoms, decline in absolute lymphocyte count post exposure, and chromosomal analysis of peripheral blood lymphocytes. Moreover, dose assessment on the basis of calculation from reconstruction of the radiation event may be required. Experience of a criticality accident occurring in 1999 at Tokai-mura, Japan, showed that ARS led to multiple organ failure (MOF). This article will review ARS and discuss the possible mechanisms of MOF developing from ARS.

• Radiation Oncology Journal
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• 제14권4호
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• pp.281-290
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• 1996

목적 : 흉부방사선조사시 심장이 포함됨으로써 다양한 정도의 심장손상이 발생되고 이로써 방사선치료의 효과를 감소시키게 된다. 따라서 이들의 발생빈도를 감소시키기 위해 여러방법이 시도되었으며 이중 혈류장애 개선제로 알려진 pentoxifylline (3,7-dimethyl-1(5-oxyhexyl-xanthine)) (이하 PTX로 약함)을 방사선조사와 동시에 투여하여 심장에서의 방사선손상을 감소시키고자 하였으며 이의 효과는 병리조직학적 검사를 통해 관찰하였다. 대상 및 방법 : ICR마우스 수컷 180마리를 각각 대조군, 방사선조사단독군, 방사선조사와 PTX투여군으로 구분하고 각 군은 다시 방사선조사후의 기간에 따라 1, 3, 6, 10일과 2, 3, 4, 6, 8, 12, 16, 20주의 12개 소군으로 나누었다. 방사선조사는 4 MV 선형가속기를 이용하여 15Gy를 일회로 심장을 포함한 흉부에 시행하였고 PTX투여는 1일 50mg/kg을 방사선조사 다음날부터 실험완료시까지 매일 배부의 좌우측에 번갈아 피하주사 하였다. 일정한 관찰기간후 심장을 절제 하여 병리학적 검사를 시행하였고 이들의 변화를 급성과 만성으로 나누어 병변의 정도에 따라 각각 4등급으로 분류한 후 합산하여 점수화하였다. 이들 결과는 Student's t-test를 이용하여 각군의 관찰기간에 따른 변화와 각 군간의 병리소견상 변화의 차이점에 대해 통계적 유의성이 검증되었다. 결과 : 방사선조사가 시행되지 않은 대조군은 비특이성심근염외에는 별 특이한 소견을 보여주지 않았다. 방사선조사후의 급성변화는 이염성백혈구성 심낭염과 혈관내피세포의 공포화 및 풍선화가 있었고 만성기 심장손상의 변화로는 단핵세포성 심낭염, 심낭섬유화, 혈관내피세포변화, 심근의 퇴행성 변화와 심근섬유화등이 관찰되었다. 심장손상의 병리학적 소견을 각 군에 따라 점수화하여 비교한 결과 급성변화에서는 방사선조사단독군이 1일-6주에 2-4점을, PTX투여군이 1-3점의 분포를 보여 주었다. 이들 변화는 각 군 모두 3주까지 유사하였으며 4주이후부터 PTX투여군의 변화소견이 방사선조사단독군에 비해 빨리 회복됨을 보여 주었고 이는 통계학적으로 의미있는 소견임이 확인 되었다. 만성심장손상소견은 방사선조사단독군이 4-8주에 5-6점의 변화소견을 보였고 이후 12주에 심근의 섬유화현상시작으로 7-9점의 병리소견을 보였으며 PTX투여군은 4-12주에 이르기까지 1-4점을 보인후 16주의 심근섬유화현상으로 5-6점의 소견을 보여주었고 이들 군간의 변화정도의 차이는 통계학적으로 유의성이 있음이 확인 되었다. 결론 : PTX투여 결과 급성 방사선심장손상의 병리학적 변화정도는 유사하였으나 빨리 회복되는 추세가 관찰되었고 만성 방사선심장손상에서는 방사선조사단독군에 비해 심근의 퇴행성 변화 및 섬유화정도의 의미 있는 억제 및 감소효과를 보여주었다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4101-4105
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• 2012

Purpose: The degree of radiation injury to kidneys which are located within the limits of radiotherapy area is determined by the volume and the dose of radiation to which the organ is exposed. When the tolerance dose of the kidney is exceeded after a latent period of 6 months acute nephritis develops and after 18 months chronic nephritis ensues. Melatonin is known to prevent the oxidative injury of toxins and radiotherapy with its free radical scavenging capacity. Methods and Materials: In this study 8 weeks old 24 Sprague -Dawley rats were allocated into 4 groups: Control group; Radiotherapy group (20 Gy bilaterally in 5 fractions); Melatonin group (10 mg/kg intraperitoneally), and Melatonin+radiotherapy group (20 Gy Radiotherapy in 5 fractions+ melatonin 10 mg/kg intraperitoneally). After a follow-up period of 6 months BUN was determined in all groups. After rats were euthanized the kidneys were removed for histopathological examination under both light and electron microscopes. Results: After 6 months follow-up, both at light and electron microscopy levels, the rats in radiotherapy+melatonin group were significantly protected against the radiation injury comparing to radiotherapy group (p<0.05). Conclusion: It was shown in this experimental model that melatonin has protective effects against radiation injury to kidneys.

• Journal of Radiation Protection and Research
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• 제29권4호
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• pp.237-242
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• 2004

방사선피폭 후 급성조혈계 손상에 대한 Melatonin과 Ge-132의 방어효과를 8 Gy의 선량으로 급성, 전신피폭 된 마우스에서 연구하였다. Melatonin은 피폭 1시간 전에 200 mg/kg의 용량으로 복강 내 주사하였고, Ge-132는 130 - 150 mg/kg/d의 용량으로 피폭 후 5일째부터 20일째까지 경구복용 시켰다. 방사선방어 효과를 평가하기 위해 비장에서 TUNEL assay를 실시하였고 혈액 내 림프구와 총 백혈구 수치를 측정하였다. 피폭 후 30일째까지의 생존분석을 위해 4 실험군들 (피폭단독군, melatonin 전처치군, Ge-132 후처치군, melatonin 전처치 및 Ge-132 후처치군)에서 날짜경과에 따른 사망을 측정하였다. 피폭단독군과 melatonin 전처치군 간에 세포고사지수 (47.8% vs 45.9%, p=0.385)와 림프구 수치 ($97/{\mu}{\ell}\;vs\;101/{\mu}{\ell}$, p=0.898)에서 차이가 없었으나, 총 백혈구 수치는 melatonin 전처치군에서 유의하게 높은 수치 ($147/{\mu}{\ell}\;vs\;306/{\mu}{\ell}$, p=0.010)를 보였다. 피폭 후 30일째의 생존율은 피폭단독군, melatonin 전처치군, Ge-132 후처치군, 그리고 melatonin 전처치 및 Ge-132 후처치군에서 각각 21.4%, 100%, 35.7%, 그리고 85.7%였다. 실험군들 간의 생존분석에서 melatonin 전처치 군은 피폭단독군(p=0.000)이나 Ge-132 후처치군(p=0.0003)에 유의하게 높은 생존을 보였다. 본 연구결과는 방사선피폭 후 급성조혈계증후군에 대하여 melatonin이 방사선방어제로서 효능을 지님을 보여주고 있다.

• Clinical Endoscopy
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• 제55권1호
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• pp.22-32
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• 2022

Radiotherapy (RT) is a treatment modality that uses high-energy rays or radioactive agents to generate ionizing radiation against rapidly dividing cells. The main objective of using radiation in cancer therapy is to impair or halt the division of the tumor cells. Over the past few decades, advancements in technology, the introduction of newer methods of RT, and a better understanding of the pathophysiology of cancers have enabled physicians to deliver doses of radiation that match the exact dimensions of the tumor for greater efficacy, with minimal exposure of the surrounding tissues. However, RT has numerous complications, the most common being radiation proctitis (RP). It is characterized by damage to the rectal epithelium by secondary ionizing radiation. Based on the onset of signs and symptoms, post-radiotherapy RP can be classified as acute or chronic, each with varying levels of severity and complication rates. The treatment options available for RP are limited, with most of the data on treatment available from case reports or small studies. Here, we describe the types of RT used in modern-day medicine and radiation-mediated tissue injury. We have primarily focused on the classification, epidemiology, pathogenesis, clinical features, treatment strategies, complications, and prognosis of RP.

• Asian Pacific Journal of Cancer Prevention
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• 제16권16호
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• pp.7331-7335
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• 2015

Background: Concurrent chemoradiation with three weekly high dose cisplatin is the non-surgical standard of care for the treatment of locally advanced head and neck cancers. Although this treatment regime is efficacious, it has high acute toxicity, which leads not only to increased treatment cost, but also to increased overall treatment time. Hence, the current study was undertaken to evaluate the acute toxicity and tumor response in head and neck cancer patients treated with concurrent chemoradiation using $40mg/m^2$ weekly cisplatin, which has been our institutional practice. Materials and Methods: This single institution retrospective study included data for 287 head and neck cancer patients treated with concurrent chemoradiation from 2012 to 2014. Results: The mean age of the patients was 48.8 years. The most common site of involvement was oral cavity. Most of the study patients presented with advanced stage disease. The mean overall treatment time was 56.9 days. Some 67.2% had overall complete response to treatment as documented till 90 days from the start of treatment. According to the Radiation Therapy Oncology Group (RTOG) acute radiation morbidity scoring criteria, mucositis was seen in 95.1% of the patients. Dermatitis and emesis were observed in 81.9% and 98.6%, respectively. Regarding haematological toxicity, 48.8% and 29.6% suffered from anaemia and leukopenia, respectively, during treatment. Acute kidney injury was assessed using the Common Terminology Criteria for Adverse Events (CTCAE), and was found in 18.8% of the patients. Conclusions: Concurrent chemoradiotherapy with weekly cisplatin is an effective treatment regime for head and neck cancers with reasonable toxicity which can be used in developing countries, where cost of treatment is so important.