• Journal of Radiation Protection and Research
• /
• 제39권4호
• /
• pp.168-175
• /
• 2014

This study was designed to assess whether the conventional tangential technique, using a multileaf collimator (MLC), allows a reduced dose to the organs at risk (OAR) in breast radiation therapy. A total of forty right and left 20 for each breast cancer patients that underwent radiation therapy after breast conserving surgery were included in this study. For each patient, the planning target volume (PTV) and OAR (heart, left anterior descending artery (LAD), liver and lung) were defined and dose distribution were produced for conventional tangential beams using 6 MV photons. The treatment plans were made using the following two techniques for all patients. For the first plan (P1), MLC was designed to shield as much of OAR as possible without compromising the coverage of PTV. In the second plan (P2), the treatment plan was created without using MLC. Dose-volume histograms for OARs were calculated for all plans. For left breast cancer, the percentage of maximum dose ($D_{max%}$) and mean dose ($D_{mean%}$) of OARs (heart and LAD) were calculated, and for right breast cancer, the percentage of the mean dose ($D_{mean%}$) of the liver was calculated. The $D_{mean%}$ of the lung was calculated in all patients. The mean values of $D_{max%}$ of the heart ($86.9{\pm}19.5%$ range, 35.1-100.6%) in P1 were significantly lower than in P2 ($98.3{\pm}3.4%$ range, 91.7-105.2%) (p=0.001). The mean values of $D_{max%}$ of LAD ($78.4{\pm}22.5%$ range, 26.5-99.7%) in P1 was significantly lower than in P2 ($93.3{\pm}8.1%$ range, 67.9-102.1%) (p<0.001). In P1, the mean values of $D_{mean%}$ of the liver ($4.8{\pm}2.0%$) were significantly lower than in P2 ($6.2{\pm}2.5%$) (p<0.001). The mean values of $D_{mean%}$ of the lung were significantly lower in P1 ($9.3{\pm}2.3%$) than in P2 ($9.7{\pm}2.4%$) (p<0.001). P1, by using MLC, allows a significantly reduced dose to OAR compared with P2. We can suggest that it is reasonable to routinely use MLC in the conventional tangential technique for breast radiation therapy considering the primary tumor location.

• Radiation Oncology Journal
• /
• 제31권4호
• /
• pp.239-246
• /
• 2013

Purpose: We explored whether the deep inspiration breath hold (DIBH) technique using Abches during left-sided breast irradiation was effective for minimizing the amount of radiation to the heart and lung compared to free breathing (FB). Materials and Methods: Between February and July 2012, a total of 25 patients with left-sided breast cancer underwent two computed tomography scans each with the DIBH using Abches and using FB after breast-conserving surgery. The scans were retrospectively replanned using standardized criteria for the purpose of this study. The DIBH plans for each patient were compared with FB plans using dosimetric parameters. Results: All patients were successfully treated with the DIBH technique using Abches. Significant differences were found between the DIBH and FB plans for mean heart dose (2.52 vs. 4.53 Gy), heart V30 (16.48 vs. $45.13cm^3$), V20 (21.35 vs. $54.55cm^3$), mean left anterior descending coronary artery (LAD) dose (16.01 vs. 26.26 Gy, all p < 0.001), and maximal dose to $0.2cm^3$ of the LAD (41.65 vs. 47.27 Gy, p = 0.017). The mean left lung dose (7.53 vs. 8.03 Gy, p = 0.073) and lung V20 (14.63% vs. 15.72%, p = 0.060) of DIBH using Abches were not different significantly compared with FB. Conclusion: We report that the use of a DIBH technique using Abches in breathing adapted radiotherapy for left-sided breast cancer is easily feasible in daily practice and significantly reduces the radiation doses to the heart and LAD, therefore potentially reducing cardiac risk.

• Journal of Chest Surgery
• /
• 제40권10호
• /
• pp.680-684
• /
• 2007

배경: IB기 비소세포폐암의 가장 효과적인 치료는 완전 절제이나, 수술 후 재발이 생기면 생존율이 떨어진다. 최근 IB기 비소세포폐암의 완전 절제 후 시행하는 보조 요법에 대해 관심이 높아지고 있다. 적절한 보조 요법을 사용하기 위해서는 재발의 위험 인자를 아는 것이 중요하다. 대상 및 방법: 114명을 대상으로 연구하였으며, 환자의 성별, 나이, 수술 방법, 조직학적 유형, 분화의 정도, 종양의 크기, 장측 흉막 침범 유무 등과 재발과의 관계를 분석하였다. 생존율과 무재발률은 Kaplan-Meier 방법으로 구하였으며, log rank test로 단변량 분석을, Cox's proportional hazard model을 이용하여 다변량 분석을 하였다. p값이 0.05 미만인 경우에 통계학적으로 유의하다고 판정하였다. 결과: 3년 생존율 및 무재발률은 각각 87.0%, 79.4%였다. 단변량 분석에서 분화도가 통계학적으로 의미가 있었으며, 다변량 분석에서도 저분화의 경우가 예후가 좋지 않았다. 결론: 완전 절제된 IB기 비소세포폐암 환자에서 저분화도가 재발과 연관된 인자이므로 수술 후 보조 요법이 필요할 것으로 기대된다.

• Journal of Korean Neurosurgical Society
• /
• 제64권2호
• /
• pp.271-281
• /
• 2021

Objective : Immune checkpoint inhibitors (ICIs) are approved for treating non-small-cell lung cancer (NSCLC); however, the safety and efficacy of combined ICI and Gamma Knife radiosurgery (GKS) treatment remain undefined. In this study, we retrospectively analyzed patients treated with ICIs with or without GKS at our institute to manage patients with brain metastases from NSCLC. Methods : We retrospectively reviewed medical records of patients with brain metastases from NSCLC treated with ICIs between January 2015 and December 2017. Of 134 patients, 77 were assessable for brain responses and categorized into three groups as follows : group A, ICI alone (n=26); group B, ICI with concurrent GKS within 14 days (n=24); and group C, ICI with non-concurrent GKS (n=27). Results : The median follow-up duration after brain metastasis diagnosis was 19.1 months (range, 1-77). At the last follow-up, 53 patients (68.8%) died, 20 were alive, and four were lost to follow-up. The estimated median overall survival (OS) of all patients from the date of brain metastasis diagnosis was 20.0 months (95% confidence interval, 12.5-27.7) (10.0, 22.5, and 42.1 months in groups A, B, and C, respectively). The OS was shorter in group A than in group C (p=0.001). The intracranial disease progression-free survival (p=0.569), local progression-free survival (p=0.457), and complication rates did not significantly differ among the groups. Twelve patients showed leptomeningeal seeding (LMS) during follow-up. The 1-year LMS-free rate in treated with ICI alone group (69.1%) was significantly lower than that in treated with GKS before ICI treatment or within 14 days group (93.2%) (p=0.004). Conclusion : GKS with ICI showed no favorable OS outcome in treating brain metastasis from NSCLC. However, GKS with ICI did not increase the risk of complications. Furthermore, compared with ICI alone, GKS with ICI may be associated with a reduced incidence of LMS. Further understanding of the mechanism, which remains unknown, may help improve the quality of life of patients with brain metastasis.

• Korean Journal of Radiology
• /
• 제22권12호
• /
• pp.2082-2093
• /
• 2021

Objective: We conducted a systematic review and meta-analysis of the tissue adequacy and complication rates of percutaneous transthoracic needle biopsy (PTNB) for molecular analysis in patients with non-small cell lung cancer (NSCLC). Materials and Methods: We performed a literature search of the OVID-MEDLINE and Embase databases to identify original studies on the tissue adequacy and complication rates of PTNB for molecular analysis in patients with NSCLC published between January 2005 and January 2020. Inverse variance and random-effects models were used to evaluate and acquire meta-analytic estimates of the outcomes. To explore heterogeneity across the studies, univariable and multivariable metaregression analyses were performed. Results: A total of 21 studies with 2232 biopsies (initial biopsy, 8 studies; rebiopsy after therapy, 13 studies) were included. The pooled rates of tissue adequacy and complications were 89.3% (95% confidence interval [CI]: 85.6%-92.6%; I² = 0.81) and 17.3% (95% CI: 12.1%-23.1%; I² = 0.89), respectively. These rates were 93.5% and 22.2% for the initial biopsies and 86.2% and 16.8% for the rebiopsies, respectively. Severe complications, including pneumothorax requiring chest tube placement and massive hemoptysis, occurred in 0.7% of the cases (95% CI: 0%-2.2%; I² = 0.67). Multivariable meta-regression analysis showed that the tissue adequacy rate was not significantly lower in studies on rebiopsies (p = 0.058). The complication rate was significantly higher in studies that preferentially included older adults (p = 0.001). Conclusion: PTNB demonstrated an average tissue adequacy rate of 89.3% for molecular analysis in patients with NSCLC, with a complication rate of 17.3%. PTNB is a generally safe and effective diagnostic procedure for obtaining tissue samples for molecular analysis in NSCLC. Rebiopsy may be performed actively with an acceptable risk of complications if clinically required.

• 한국의학물리학회지:의학물리
• /
• 제25권4호
• /
• pp.210-217
• /
• 2014

이 연구는 비편평화여과기(flattening filter-free, FFF) 빔을 이용한 폐 정위절제방사선치료(stereotactic ablative radiotherapy, SABR)에 대하여 서로 다른 선량계산 알고리즘의 선량적 효과를 조사하였다. SABR를 받은 10명의 폐암 환자를 대상으로하여 평가하였다. 모든 치료계획은 Eclipse 치료계획시스템의 Acuros XB (AXB) 알고리즘을 이용하여 수립되었다. 다른 선량계산 알고리즘과 비교를 위하여, 추가적으로 anisotropic analytic algorithm (AAA) 알고리즘을 적용한 치료계획을 재 수립하였다. 두 알고리즘 평가를 위해서, 치료표적과 손상위험장기의 선량체적히스토그램(dose-volume histogrim, DVH)를 분석하였다. 그리고 기술적 인자로써 계산시간과 총 MU 값을 평가하였다. DVH 비교분석을 통해, PTV의 최대선량은 AXB이 AAA 보다 5.2% 높았으며 최소선량은 4.4% 낮게 나타났다. PTV의 $V_{105%}$에서 7.06%까지 큰 차이를 나타났다. 폐의 최대선량은 AXB 치료계획에서 약간 크게 나타났다. 동측성 폐에 5, 10과 20 Gy 선량이 조사되는 체적은 AAA 보다 AXB에서 더 크게 나타났으나 대측성 폐에 대해서는 거의 비슷하게 나타났다. 척수와 심장에서 최대선량의 차이도 크지 않았다. 계산시간의 경우, AXB가 AAA보다 13.7% 정도 소요시간이 적었고 MU 값은 AXB에서 3.47% 더 많았다. 이 연구의 결과들은 회전조절치료 기법을 포함하여 FFF 빔이 적용된 폐 SABR 치료계획에서 AXB 알고리즘은 선량계산의 정확성과 계산시간의 감소의 장점을 제공할 수 있을 것이다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권15호
• /
• pp.6527-6534
• /
• 2015

Background: In Japan, in comparison with the rest of the world the death rate of lung cancer is low although the smoking rate is relatively high. This is the so-called "Japanese smoking paradox". A healthy diet is proposed to attenuate the risk without quitting smoking. We here examined the relationships between smoking status (SS) and the consumption of food and nutrient in Japan. Materials and Methods: Totals of 5,587 men and 2,718 women were divided into three (non-smokers, smokers and heavy smokers) and two (non-smokers and smokers) groups, respectively, according to pack-year, which represents the amount of smoking over a long period. Food and nutrient consumption was estimated with a validated food frequency questionnaire. Using general linear models, food and nutrient consumption was estimated for each group in men and women, separately. Results: In men, SS was positively related to consumption of rice, 3 alcoholic beverages, carbohydrate, alcohol and other 8 foods/nutrients (p< 0.05 for all) and negatively to those of protein animal, fat, fatty acids, dietary fiber, isoflavones and 36 other foods/nutrients (p<0.05 for all). In women, SS was positively associated with intake of 13 foods/nutrients, while being negatively associated with those of rice, energy, dietary fiber, and 14 other foods/nutrients (p<0.05 for all). Conclusions: Our results support lower intake of vegetables and fruits rich in antioxidants, which are thought as preventive factors for many diseases, in smokers.

• 대한두경부종양학회지
• /
• 제14권1호
• /
• pp.35-39
• /
• 1998

Objectives: Minimal improvement in the long-term survival of head and neck cancer(HNC) patients has occurred despite a multitude of advances in the control of loco regional disease and a second primary malignancy(SPM) contribute to the continued poor prognosis for the HNC patients. This study was performed in order to identify the clinical characteristics of SPM in the HNC patients. Materials and Methods: The medical records of 354 patients of head and neck squamous cell carcinoma that were followed up after initial treatment during the period of 1987 through 1994 were reviewed. This study examines the medical records of 354 patients with squamous cell carcinoma of the head and neck, of whom 26 subsequently developed a second neoplasm. Results: The actuarial SPM rate was 7.3%, and median time to presentation for the SPM was 26.8 months. The SPM were more likely to occur in male patients who had oral cavity index tumors. Patient whose index tumor was small at diagnosis had a greater chance of developing a second tumor as did those with no cervical lymph node metastases to the neck. Initial treatment modality was not associated with an increased risk of developing a second tumor. The commonest sites for the SPM were the lung and other head and neck area. The 3-year survival for patients who developed a secondary tumor from the time of its diagnosis was 27.8%. Conclusion: The SPM in the head and neck cancer patients are not uncommon and early detection of the SPM will contribute to increase the long-term survival of HNC patients.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권20호
• /
• pp.8775-8778
• /
• 2014

Background: To explore the relationship between polymorphisms of interleukin17 (IL-17) gene(A-832G 7488A/G) and the susceptibility to silicosis, a risk factor for lung cancer. Materials and Methods: A total of 113 silicosis patients and 116 workers without silicosis were enrolled in the case-control study. IL-17A A-832G and IL-17F 7488A/G polymorphisms were evaluated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The frequencies of AA,GG and AG of IL-17A A-832G locus in the case and control groups were 46.9%, 8.0%, 45.1%, and 49.2%, 7.6%, 43.2%, respectively, with no significant differences (p>0.05).The GG genotype in the IL-17F (7488A/G) locus was not found. The frequencies of AA and GA of IL-17F 7488A/G locus in the case and control groups were 84.1%, 15.9% and 66.4%, 33.6%, respectively (p<0.05). Analysis of combined effects showed that the individuals with GG+AG genotype of IL-17A and GG+GA genotype of IL-17F are protected against silicosis (OR=0.469). Conclusions: IL-17F 7488A/G is associated with susceptibility to silicosis, and G allele may have a protective effect. No relationship was found between IL-17A gene polymorphisms at A-832G and silicosis.

• Radiation Oncology Journal
• /
• 제38권2호
• /
• pp.138-147
• /
• 2020

Purpose: To evaluate the dosimetric variations in patients of head and neck cancer treated with definitive or adjuvant radiotherapy using optimized non-coplanar (ncVMAT) beams with coplanar (cVMAT) beams using volumetric arc therapy. Materials and Methods: Twenty-two patients of head and neck cancer that had received radiotherapy using VMAT in our department were retrospectively analyzed. Each of the patients was planned using coplanar and non-coplanar orientations using an optimized couch angle and fluences. We analyzed the Conformity Index (C_IRTOG), Dose Homogeneity Index (DHI), Heterogeneity Index (HI_RTOG), low dose volume, target and organs-at-risk coverage in both the plans without changing planning optimization parameters. Results: The prescription dose ranged from 60 Gy to 70 Gy. Using ncVMAT, C_IRTOG, DHI and HI_RTOG, and tumor coverage (ID_95%) had improved, low dose spillage volume in the body V_5Gy was increased and V_10Gy was reduced. Integral dose and intensity-modulated radiation therapy factor had increased in ncVMAT. In the case of non-coplanar beam arrangements, maximum dose (D_max) of right and left humeral head were reduced significantly whereas apex of the right and left lung mean dose were increased. Conclusion: The use of ncVMAT produced better target coverage and sparing of the shoulder and soft tissue of the neck as well as the critical organ compared with the cVMAT in patients of head and neck malignancy.