• Journal of the Korean Physical Society
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• 제73권10호
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• pp.1577-1583
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• 2018

Tumor-treating fields therapy involves placing pads onto the patient's skin to create a low- intensity (1 - 3 V/cm), intermediate frequency (100 - 300 kHz), alternating electric field to treat cancerous tumors. This new treatment modality has been approved by the Food and Drug Administration in the USA to treat patients with both newly diagnosed and recurrent glioblastoma. To deliver the prescribed electric field intensity to the tumor while minimizing exposure of organs at risk, we developed an optimization method for the electric field distribution in the body and compared the electric field distribution in the body before and after application of this optimization algorithm. To determine the electric field distribution in the body before optimization, we applied the same electric potential to all pairs of electric pads located on opposite sides of models. We subsequently adjusted the intensity of the electric field to each pair of pads to optimize the electric field distribution in the body, resulting in the prescribed electric field intensity to the tumor while minimizing electric fields at organs at risk. A comparison of the electric field distribution within the body before and after optimization showed that application of the optimization algorithm delivered a therapeutically effective electric field to the tumor while minimizing the average and the maximum field strength applied to organs at risk. Use of this optimization algorithm when planning tumor-treating fields therapy should maintain or increase the intensity of the electric field applied to the tumor while minimizing the intensity of the electric field applied to organs at risk. This would enhance the effectiveness of tumor-treating fields therapy while reducing dangerous side effects.

• Journal of Korean Neurosurgical Society
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• 제63권6호
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• pp.681-688
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• 2020

Glioblastoma (GBM) is one of the most common tumors of the central nervous system, which is the most lethal brain cancer. GBM treatment is based primarily on surgical resection, combined with radiotherapy and chemotherapy. Despite the positive treatment, progression free survival and overall survival were not significantly prolonged because GBM almost always recurs. We are always looking forward to some new and effective treatments. In recent years, a novel treatment method called tumor treating fields (TTFields) for cancer treatment has been proposed. TTFields devices were approved by the Food and Drug Administration (FDA) for adjuvant treatment of recurrent and newly diagnosed GBMs in 2011 and 2015, respectively. This became the first breakthrough treatment for GBM in the past 10 years after the FDA approved bevacizumab for patients with relapsed GBM in 2009. This paper summarized the research results of TTFields in recent years and elaborated the mechanism of action of TTFields on GBM, including cell and animal experimental research, clinical application and social benefits.

• Journal of Korean Neurosurgical Society
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• 제64권3호
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• pp.469-471
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• 2021

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3747-3750
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• 2013

Purpose: To evaluate the efficacy of conservative surgery plus chemo-, radio-therapy in treating patients with early stage breast cancer. Patients and Methods: Eligible patients were treated by postoperative chemotherapy as well as whole-breast irradiation with tumor bed boost. Postoperative radiotherapy consisted of 6 MV whole breast linear accelerator irradiation with two tangential half fields to a total dose of 45~50 Gy, followed by $10{\sim}15MeV{\beta}$ boost irradiation to tumor bed for 10~20Gy, total dose 56~66Gy. Results: Fifty-two patients were enrolled. Overall 1-, 2- and 3 year survival rates were 98.1%, 92.3%, and 90.4%, respectively, with a local recurrence rate of 5.77%. Cosmetic results were evaluated as good by doctors in 90.4% of patients. Conclusions: Breast conservative surgery combined with chemo- radio-therapy could be a treatment option for Chinese patients with early stage breast cancer.

• 한국멀티미디어학회논문지
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• 제20권7호
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• pp.979-985
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• 2017

This paper, which covers a fluorescence microscopy image of brain tumor cells, looks at drug reactions by treating different types and concentrations of drugs on a plate of $24{\times}16$ wells. Due to the limitation of the field of view, a well was taken into 9 field images, and each has an overlapping area with its neighboring fields. To analyze more precisely, image stitching is needed. The basic method is finding a similar area using normalized cross-correlation (NCC). The problem is that some overlapping areas may not have any duplicated cells that help to find the matching point. In addition, the cell objects have similar sizes and shapes, which makes distinguishing them difficult. To avoid calculating similarity between blank areas and roughly distinguishing different cells, thresholding is added. The thresholding method classifies background and cell objects based on fixed thresholds and finds the location of the first seen cell. After getting its location, NCC is used to find the best correlation point. The results are compared with a simple boundary stitched image. Our proposed method stitches images that are connected in a grid form without collision, selecting the best correlation point among areas that contain overlapping cells and ones without it.

• 한국진공학회지
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• 제20권4호
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• pp.307-312
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• 2011

정상 세포로부터 암과 같은 종양세포를 제거하는 방법으로 라디오주파수의 전자파를 이용하여 세포가 사멸되는 임계온도보다 높은 온도로 국소 가열하는 발열 치료법이 임상에서 시술되고 있다. 그러나 이 기술은 임상에서 활발히 사용되기에는 여러 가지 제약 요인이 존재한다. 본 연구에서는 교류파 대신에 미소 직류전원을 사용하여 국소부위에 열을 발생하는 안전성이 증가된 방법의 실효성을 이론적으로 입증하고자 한다. 종양세포의 형태에 따라 적당한 모양의 전극을 종양조직에 삽입하고 종양조직의 형태와 유사한 열분포를 갖도록 제어하는 기술을 개발한다. 열원은 조직 내에 삽입된 전극과 매질에 형성되는 전기장에 의한 저항열이다. 종양 조직 내에 삽입된 전극에 10 V, 20 V, 30 V를 각각 인가하고 시간에 따른 열분포를 전산모의 하였다. 결과적으로, 20 V를 전극에 인가하면 1~2 분 이내에 버섯모양의 등온도 분포를 갖으며 세포를 고사시키는 온도 이상의 치료영역이 형성됨을 보였다. 4개의 전극에 대칭적인 전위를 인가하고 $50^{\circ}C$ 이상의 온도 분포를 암 조직의 모양과 유사하게 분포하도록 조절하여 효과적인 치료를 수행 할 수 있는 가능성을 제시하고자 한다.

• Radiation Oncology Journal
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• 제13권4호
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• pp.377-383
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• 1995

목적 : 자궁내막암 1, 2기 환자에서 수술전 방사선 치료와 수술후 방사선 치료의 성적을 후향적으로 비교 분석하여 적합한 치료 방법을 얻고자 본 연구를 시행하였다. 방법 : 1985. 1월부터 1991 12월까지 연세대학교 의과대학 방사선종양학과에 내원하여 방사선 치료를 받은 자궁내막암 환자 62명을 대상으로 하였으며,이중 19명(1기 12명, 2기 7명)은 수술전4-6주전에 방사선 치료를 받았으며(1군), 43명(1기 32명, 2기 11명)은 수술후 4-5주후에 방사선 치료를 받았다(2군). 2군중에 질내조사만 시행된 1명의 환자를 제외한 61명의 환자에서 모두 외부방사선 치료가 시행되었으며, 1관의 $70{\%}$(13/19)와 2군의 $44{\%}$(23/42)의 환자에서는 외부방사선 치료와 강내조사가 시행되었다. 외부방사선 조사는 180 cGy를 하루에 한 번씩 주 5회 시행하였으며, 총 방사선 조사선량은 39.6-55 Gy(중앙값 : 45 Gy)였다. 강내조사는 1군에서는 Point A에 20-39.6 Gy(중앙값 ; 39 Gy)가 조사되었고, 2군에서는 질 표면에서 0.5cm 깊이에 18-30 Gy(중앙값 ; 21 Gy)가 조사되었다. 결과 : 수술전 방사선 치료군과 수술후 방사선 치료군의 5년 생존율은 각각 $89{\%},\;98{\%}$로 통계적으로 유의한 차이는 없었다(p>0.1). 또한 병기.분화도,조직학적 형태에 따른 양 군간의 5년 생존율도 차이가 없었다 1군에서 수술전 방사선 치료후에 잔재암의 존재 여부에 따라서는 5년 생존율의 차이가 없었으며(p>0.1), 2군에서 림프절의 전이 여부에 따라 5년 생존율이 통계적으로 유의한 차이를 보였다(P<0.5). 치료에 따른 부작용은 1군이 더 많았다($16{\%}$ vs $5{\%}$). 결론 : 수술후 방사선 치료 방법은 수술전 방사선 치료 방법에 비하여 정확한 병의 진행 정도를 알 수 있으며, 부작용이 적음으로 자궁내막암의 치료에 좀더 적합한 치료 방법이라고 하겠다.