• Radiation Oncology Journal
• /
• 제31권3호
• /
• pp.125-130
• /
• 2013

Purpose: We investigated the role of radiotherapy (RT) for pancreatobiliary neuroendocrine tumors (PB-NETs). Materials and Methods: We identified 9 patients with PB-NETs who received RT between January 2005 and March 2012. Of these 9 patients, 4 were diagnosed with NETs in the pancreas and 5 were diagnosed with NETs in the gallbladder. All patients received RT to the primary tumor or resection bed with a median total irradiation dose of 50.4 Gy, with or without chemotherapy. Results: The tumor response rate and tumor control rate in the RT field were 60% and 100 %, respectively. All 4 patients who underwent surgery had no evidence of disease in the RT field. Of the 5 patients who received RT to the primary gross tumor, 1 had complete response, 2 had partial response, and 2 had stable disease in the RT field. The median time to progression was 11 months. Of the 9 patients, four patients had no progression, and 5 patients had progression of disease (locoregional, 2; distant, 2; locoregional/distant, 1). Of the 4 patients without progression, 3 were treated with RT in adjuvant or neoadjuvant setting, and one received RT to primary tumor. One patient experienced radiation-induced duodenitis at 3 months after concurrent chemoradiation without treatment-related mortality. Conclusion: RT can yield local control for advanced PB-NETs. RT should be considered an essential part of multimodality treatment in management of advanced PB-NETs.

• Radiation Oncology Journal
• /
• 제27권3호
• /
• pp.111-119
• /
• 2009

목 적: 국소 진행된 직장암에서 수술 전 동시항암방사선치료 후 정확한 치료 반응 평가는 매우 중요하다. 본 연구는 국소 진행된 직장암에서 $^{18}F$-FDG PET/CT를 이용한 수술 전 항암방사선치료의 반응성 예측에 대해 알아보고자 하였다. 대상 및 방법: 2006년 8월부터 2008년 1월까지 원자력의학원에서 국소 진행된 직장암으로 수술 전 항암방사선치료를 시행한 20명의 환자를 대상으로 전향적 연구를 시행하였다. 방사선 치료는 한 회에 1.8 Gy씩 하루 1회 주 5회의 일정으로 총 50.4 Gy 시행되었고, 항암 치료는 3주 간격으로 3회 시행되었다. 모든 환자는 치료 전과 항암방사선치료 종료 6주 후에 각각 $^{18}F$-FDG PET/CT 촬영을 하였다. 모든 환자는 수술을 시행 받았고 수술 후 절제된 조직을 통해 Dworak 분류에 따른 종양의 치료에 대한 반응 정도를 평가하였다. 결 과: 20명 중 11명의 환자가 Dworak 분류에 따라 반응군에 속했으며, 나머지 9명은 비반응군으로 분류되었다. 수술 후 $SUV_{max}$값과 metabolic volume (SUV가 2.5 이상인 병변의 용적)은 수술 전 $SUV_{max}$값과 metabolic volume보다 현저히 낮았다. 그러나 반응군에서 metabolic volume의 변화를 제외하고는 통계적으로 유의한 차이는 보이지 않았다. 이 연구에서는 치료 후 반응군과 비반응군을 구분하는 cut-off value는 $SUV_{max}$가 67% 감소하는 지점으로 나타났다. 이 cut-off value를 이용하여 반응군과 비반응군을 구분하는 경우 민감도는 45.5%, 특이도는 88.9%였으며, 양성 예측률과 음성 예측률은 각각 71.4% 및 53.8%였다. 결 론: 비록 본 연구에서는 통계적으로 유의한 결과를 얻지 못하였지만, 다른 연구들을 통해 봤을 때 국소 진행된 직장암 환자에서 수술 전 방사선 및 항암 병합 요법의 효과를 판정하고 예측하는데 있어서 $^{18}F$-FDG PET/CT를 이용한 검사가 유용할 것으로 생각된다.

• Journal of Korean Neurosurgical Society
• /
• 제66권5호
• /
• pp.562-572
• /
• 2023

Objective : Bevacizumab is a feasible option for treating cerebral radiation necrosis (RN). We investigated the clinical outcome of RN after treatment with bevacizumab and factors related to the initial response and the sustained effect. Methods : Clinical data of 45 patients treated for symptomatic RN between September 2019 and February 2021 were retrospectively collected. Bevacizumab (7.5 mg/kg) was administered at 3-week intervals with a maximum four-cycle schedule. Changes in the lesions magnetic resonance image (MRI) scans were examined for the response evaluation. The subgroup analysis was performed based on the initial response and the long-term maintenance of the effect. Results : Of the 45 patients, 36 patients (80.0%) showed an initial response, and eight patients (17.8%) showed delayed worsening of the corresponding lesion. The non-responders showed a significantly higher incidence of diffusion restriction on MRI than the responders (100.0% vs. 25.0%, p<0.001). The delayed worsening group showed a significantly higher proportion of glioma pathology than the maintenance group (87.5% vs. 28.6%, p=0.005). Cumulative survival rates with sustained effect were significantly higher in the groups with non-glioma pathology (p=0.019) and the absence of diffusion restriction (p<0.001). Pathology of glioma and diffusion restriction in MRI were the independent risk factors for non-response or delayed worsening after initial response. Conclusion : The initial response of RN to bevacizumab was favorable, with improvement in four-fifths of the patients. However, a certain proportion of patients showed non-responsiveness or delayed exacerbations. Bevacizumab may be more effective in treating RN in patients with non-glioma pathology and without diffusion restriction in the MRI.

• Radiation Oncology Journal
• /
• 제20권2호
• /
• pp.172-178
• /
• 2002

목적 : 원자 번호가 높은 물질로 구성된 필름은 저 에너지 광자선에 과반응하여 선량 측정 시 인체조직에서와 다른 흡수양상을 보인다. 이러한 현상은 조사면의 경계인 반음영 및 그 외곽 부위에서 두드러지게 관찰된다. 따라서 반음영이 조사면내에 위치하게되는 세기변조치료법에서 필름을 이용한 선량 측정 시 이러한 현상이 미치는 영향을 분석하고 개선 방법을 강구하고자 한다. 대상 및 방법 : 6 MV X-선의 5~7개의 크기가 다른 고정형 조사면을 이용해 두가지 유형의 세기변조 조사면을 만들었으며 전리함 및 저감도 측정용 필름을 사용하여 각 조사면의 빔 프로파일을 측정했다. 측정 깊이와 최대 조사면적을 변화시켰으며 필름에 대해 수직 및 수평 조사하여 이에 따른 선량 분포 변화를 관찰했다. 또한 필름 선량 측정시 저 에너지 광자선에 의한 선량 과평가 현상을 막기 위해 납 필터(0.01 inch)를 필름 양측에 부착하여 이로 인한 영향을 관찰했다. 결과 : 필름만을 사용한 빔 프로파일에서는, 전리함 측정치에 비해 저 선량 영역 및 조사면 경계에서의 선량 과평가 현상이 수직 및 수평 조사 모두에서 관찰되었다. 이러한 현상은 측정 깊이가 증가함에 따라 크게 나타났으며 10cm 깊이의 역 피라미드형 세기변조 조사면 중심에서 최고 약 15%의 상대오차를 보였다. 필터를 사용한 경우에서는, 수직 조사 시 필터에 의한 선량 저 평가 현상이 관찰되었으나 수평 조사에서는 전리함 측정치와 3% 이내의 오차를 보여 매우 잘 일치하였다. 결론 : 필름을 이용한 세기변조 조사면의 선량 측정 시 선량 과반응에 의한 오차는 조사면의 조합 형태 및 반음영 위치와 밀접한 관계를 가지며, 선량 평가 시 이에 대한 고려가 필요하다. 납 필터를 사용한 수평조사 방법은 이러한 오차를 줄이는데 도움을 주며 입사 방사선의 물리적 특성을 고려한 적정 두께의 필터 선택이 요구된다.

• Radiation Oncology Journal
• /
• 제37권4호
• /
• pp.302-308
• /
• 2019

The abscopal effect is a term that has been used to describe the phenomenon in which localized radiation therapy treatment of a tumor lesion triggers a spontaneous regression of metastatic lesion(s) at a non-irradiated distant site(s). Radiation therapy induced abscopal effects are believed to be mediated by activation and stimulation of the immune system. However, due to the brain's distinctive immune microenvironment, extracranial abscopal responses following cranial radiation therapy have rarely been reported. In this report, we describe the case of 42-year-old female patient with metastatic melanoma who experienced an abscopal response following her cranial radiation therapy for her brain metastasis. The patient initially presented with a stage III melanoma of the right upper skin of her back. Approximately 5 years after her diagnosis, the patient developed a large metastatic lesion in her upper right pectoral region of her chest wall and axilla. Since the patient's tumor was positive for BRAF and MEK, targeted therapy with dabrafenib and trametinib was initiated. However, the patient experienced central nervous system (CNS) symptoms of headache and disequilibrium and developed brain metastases prior to the start of targeted therapy. The patient received radiation therapy to a dose of 30 Gy delivered in 15 fractions to her brain lesions while the patient was on dabrafenib and trametinib therapy. The patient's CNS metastases improved significantly within weeks of her therapy. The patient's non-irradiated large extracranial chest mass and axilla mass also shrank substantially demonstrating the abscopal effect during her CNS radiation therapy. Following radiation therapy of her residual chest lesions, the patient was disease free clinically and her CNS lesions had regressed. However, when the radiation therapy ended and the patient continued her targeted therapy alone, recurrence outside of her previously treated fields was noted. The disease recurrence could be due to the possibility of developing BRAF resistance clones to the BRAF targeted therapy. The patient died eventually due to wide spread systemic disease recurrence despite targeted therapy.

• Journal of Microbiology and Biotechnology
• /
• 제11권3호
• /
• pp.524-528
• /
• 2001

The measurement of radiation response using simple and informative techniques would be of great value in studying the genetic risk following occupational, therapeutic, or accidental exposure to radiation. When patients receive radiation therapy, many suffer from side effects. Since each patient receives a different dose due to different physical conditions, it is important to measure the exact dose of radiation received by each patient to lessen the side effects. Even though several biological dosimetric systems have already been developed, there is no ideal system that can satisfy all the criteria for an idean dosimetric system, especially for low-dose radiation as used in radiation therapy. In this study, an SOS Chromotest of E. coli PQ37 was evaluated as a novel dosimeter for low-dose gamma-rays. E. coli PQ37 was originally developed to screen chemical mutagens using the SOS Chromotest-a colorimtric assay, based on the induction of ${\beta}$-galactosidase ue to DNA damage. The survival fraction of E. coli PQ37 decreased dose-dependently with an increasing dose of cobalt-60 gamma-rays. Also, a good linear correlation was found between the biological damage revealed by the ${\beta}$-galactosidase expression and the doses of gamma-rays. The expression of ${\beta}$-galactosidase activity that responded to low-dose radiation under 1 Gy was $Y=0.404+(0.089{\pm}0.3)D+(-0.018{\pm}0.16)D^2$ (Y, absorbance at 420 nm; D, Dose of irradiation) as calculated using Graph Pad In Plot and Excel. When a rabbit was fed with capsules containing an agar block embdded with E. coli PQ37 showed a linear response to the radiation doses. Accordingly, the results confirm that E. coli PQ37 can be used as a sensitive biological dosimeter fro cobalt-60 gamma-rays. To the best of our knowledge, this is the first time that a bacterium has been used as a biological dosimeter, especially for low-dose radiation.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2004년도 추계학술발표회 발표논문집
• /
• pp.1206-1207
• /
• 2004

• Journal of Radiation Protection and Research
• /
• 제21권3호
• /
• pp.201-215
• /
• 1996

Radiation and radioactive materials serve man in many beneficial ways. Diagnostic X-ray, radiation therapy, and other nuclear medicine uses of radioactivity save thousands of lives each year. Industrial application of radiation, such as radiography, make many manufactured products more reliable and less expensive. Nuclear power plants are producing more electrical power each year and reducing our dependence on imported oil. However, radiation can and dose produce harmful effects particularly as the reault of a radiation accident in which a victim receives as the result of a radiation accident in which a victim receives a large dose. Fortunately such accidents are very rare and recently we need more electric power produced by nuclear power plants. Considering increase of use of radiation or radioactive materials, we have to establish the radiological emergency response system prepared for radiation accidents.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권sup3호
• /
• pp.287-291
• /
• 2016

Cervical cancer is one of the most common gynecological cancers in Iranian women. This study was initiated to assess whether the combination of paclitaxel and cisplatin with radiation might feasible for these patients. The aim was to assess tumor response and toxicity of weekly cisplatin and paclitaxel along with radiotherapy in the treatment of cervical cancer. Women with primary untreated squamous cell carcinoma of the cervix with FIGO stages IB2 to IIIB were treated with weekly injections of cisplatin 30 mg/m2 and paclitaxel 35 mg/m2 for 5-6 weeks along with radiotherapy. A total of 25 patients were enrolled in this study who completed the intended treatment. Disease was assessed prior to treatment by pelvic examination and contrast enhanced MRI of the abdomen and pelvis. Response was assessed 1 month after completion of treatment by physical examination and 3 months after also by MRI.Toxicity was assessed and was graded using RTOG grading. There was a complete response rate of 84% after 3 months. The major toxicity was grade 1 and 2 anemia (92%). The mean duration of treatment was 58 days. In conclusion, combination chemotherapy with cisplatin and paclitaxel along with radiotherapy in patients with locally advanced squamous cell carcinoma of cervixwas well tolerated, in contrast to other studies, but it seems that there was no increase in tumor response and progression free survival with this treatment regimen.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2004년도 추계학술발표회 발표논문집
• /
• pp.1135-1135
• /
• 2004