A New Technique Using 4DCT Scans to Create Custom Cardiac Blocks for Left-Sided Breast Cancer Treatments

PurposeFor patients who receive treatment for left breast cancer, cardiac toxicity increases with increased radiation dose to the heart. A new method was developed using 4-dimensional computed tomography (CT) scans to improve custom cardiac blocks to minimize heart dose.Methods and materialsFour-dimensional CT scans were acquired, and a maximum intensity projection (MIP) heart was contoured for 20 patients. Custom heart blocks were created to fully block the MIP heart volume. A heart block based on the standard free-breathing (FB) CT image was retrospectively created. Differences in heart block sizes were compared. Differences in heart block areas and dose statistics were analyzed.ResultsIn all 20 cases, the heart block created using the 4-dimensional scan had a larger area than the corresponding FB block. The mean increase in multileaf collimator coverage was 3.9 mm (range, 0.5-20.1 mm). The mean increase in the area of the heart block was 2.58 cm² (range, 0.22-6.65 cm²). The dose-volume histogram showed that the MIP heart received 17.8 cGy (range, 0.02-70.3 cGy) more than the FB heart on average. Replanning with an FB heart block showed that the mean dose to the MIP heart increased by 16.2 cGy (range, 1.8-44.8 cGy) compared with the FB heart dose.ConclusionsFour-dimensional heart blocks accounting for intrinsic respiratory motion and cardiac motion were greater in size than FB heart blocks. These larger blocks resulted from the larger contour created from the MIP image and blocked more dose to the heart. This technique for improving custom heart blocks can be easily implemented with 4DCT machine capabilities that are currently available in clinical practice.     

Delineation of a Cardiac Planning Organ-At-Risk Volume Using Real-Time Magnetic Resonance Imaging for Cardiac Protection in Thoracic and Breast Radiation Therapy

PurposeCardiac radiation is associated with cardiotoxicity in patients with thoracic and breast malignancies. We conducted a prospective study using cine magnetic resonance imaging (MRI) scans to evaluate heart motion. We hypothesized that cine MRI could be used to define population-based cardiac planning organ-at-risk volumes (PRV).Methods and MaterialsA total of 16 real-time acquisitions were obtained per subject on a 1.5 Tesla MRI (Philips Ingenia). Planar cine MRI was performed in 4 sequential sagittal and coronal planes at free-breathing (FB) and deep-inspiratory breath hold (DIBH). In-plane cardiac motion was assessed using a scale-invariant feature transformation–based algorithm. Subject-specific pixel motion ranges were defined in anteroposterior (AP), left-right (LR), and superoinferior (SI) planes. Averages of the 98% and 67% of the maximum ranges of pixel displacement were defined by subject, then averaged across the cohort to calculate PRV expansions at FB and DIBH.ResultsData from 20 subjects with a total of 3120 image frames collected per subject in coronal and sagittal planes at DIBH and FB, and 62,400 total frames were analyzed. Cohort averages of 98% of the maximum cardiac motion ranges comprised margin expansions of 12.5 ± 1.1 mm SI, 5.8 ± 1.2 mm AP, and 6.6 ± 1.0 mm LR at FB and 6.7 ± 1.5 mm SI, 4.7 ± 1.3 mm AP, and 5.3 ± 1.3 mm LR at DIBH. Margins for 67% of the maximum range comprised 7.7 ± 0.7 mm SI, 3.2 ± 0.6 mm AP, and 3.7 ± 0.6 mm LR at FB and 4.1 ± 0.9 mm SI, 2.7 ± 0.8 mm AP, and 3.2 ± 0.8 mm LR at DIBH. Subsequently, these margins were simplified to form PRVs for treatment planning.ConclusionsWe implemented scale-invariant feature transformation-based motion tracking for analysis of the cardiac cine MRI scans to quantify motion and create cohort-based cardiac PRVs to improve cardioprotection in breast and thoracic radiation.     

内窥镜,Nd：YAG激光对食管癌,贲门癌梗阻的姑息治疗

1988年12月至1989年12月,我们对19例晚期食管癌、贲门癌梗阻或严重狭窄的患者,在内窥镜直视下行Nd:YAG激光治疗。其中食管癌10例,贲门癌9例;鳞状细胞癌10例,腺癌9例。治疗前,7例肿瘤已将管腔梗阻。治疗功率30～50W;每次治疗剂量900～2500J,中位治疗剂量为1500J/次;平均每例治疗3次(范围1～7次);治疗总剂量1500～7250J,中位治疗总剂量4000J。治疗后,患者均能顺利进食半流质食物,缓解期1～7月,中位缓解期为3个月。     

Breast Radiation and the Heart: Cardiac Toxicity and Cardiac Avoidance

The purpose of this invited review is to discuss the most recent and relevant outcome studies assessing the risk of late cardiac toxicity in women treated with radiotherapy for breast cancer and to describe the evidence-based technical factors associated with late cardiac toxicity. This review will also discuss the common radiation techniques for reducing radiation dose to the heart, which will lead to better outcomes and lower rates of late toxicity that can cause morbidity and mortality in women who have been cured of their breast cancer.     

MEDiastinal Irradiation and CArdio-Toxic Effects (MEDICATE): Exploring the Relationship between Cardiac Irradiation and High Sensitivity Troponins

AimsRadiation-induced heart disease is a late effect of cardiac irradiation and has been shown in patients with lymphoma and thoracic cancers. There is no established measurement tool to detect acute cardiac damage. However, high sensitivity troponin I and T (HsTnI and HsTnT) and echocardiograms have shown promise in some studies. A pilot trial was conducted to characterise whether these instruments may detect subclinical radiotherapy-induced cardiac damage.Materials and methodsEligible patients received high cardiac doses defined by either at least 30 Gy to 5% of cardiac volume or a mean dose of 4 Gy. HsTnI and HsTnT were measured before radiotherapy and after 2 and 4 weeks of radiotherapy; three-dimensional echocardiograms were completed before and 1 year after radiotherapy.ResultsOf 19 patients, the median ‘mean left ventricular dose’ was 3.1 Gy and the ‘mean cardiac dose’ was 8.6 Gy. Significant positive associations between HsTnI and HsTnT were observed at all time points, but there was no significant association with cardiac dose. The mean left ventricular dose and the maximum left ventricular dose were, however, associated with a decrease in ejection fraction (P = 0.054, 0.043) as well as an increase in left ventricular strain (P = 0.058).ConclusionThis study suggests that HsTnI and HsTnT are intimately related, but detection of acute cardiac damage was not shown, potentially due to limitations of these markers or low radiotherapy doses using conformal techniques. Our results also suggest subacute damage at 1 year may depend on the dose to the left ventricle. Further studies are needed, as identification of early damage could facilitate the ability to closely monitor and intervene in patients at risk for radiation-induced heart disease.     

CARDIAC ARRHYTHMIA AFTER LUNG CANCER SURGERY －－ANALYSIS OF 140 PNEUMONECTTOMY CASES

吴怀申，周允中，张良平，张新民，陈文虎，郑敏ＣＡＲＤＩＡＣＡＲＲＨＹＴＨＭＩＡＡＦＴＥＲＬＵＮＧＣＡＮＣＥＲＳＵＲＧＥＲＹ－－ＡＮＡＬＹＳＩＳＯＦ１４０ＰＮＥＵＭＯＮＥＣＴＴＯＭＹＣＡＳＥＳ￥ＷｕＨｕａｉｓｈｅｎ；ＺｈｏｕＹｕｎｚｈｏｎｇ；Ｚｈａｎｇ...     

Cell killing, radiosensitization and cell cycle redistribution induced by chronic hypoxia

Some of the biological changes associated with extreme hypoxia at 37 degrees C (less than 10 ppm pO2) were examined in Chinese hamster V79 cells. Specifically, extreme hypoxia caused an initial decrease in plating efficiency to 55% in 4 hr after the onset of hypoxia. Beyond this time, the decline in plating efficiency was more gradual reaching 35% of control at 20 hr. Flow microfluorimetry (FMF) studies, in which cells are sorted on the basis of DNA content and then assayed for viability, demonstrated that mid S phase cells were most sensitive to chronic hypoxia, with surviving fraction equal to 2.5% at 20 hr. Furthermore, the viability of G1 and G2/M cells, after 20 hr of hypoxic storage, was also reduced to 20 and 7.6%, respectively. Hypoxia also caused alterations in the cell cycle distribution of initially asynchronous cells, as determined by dual parameter FMF measurements of both cellular DNA content and incorporated BudR. In particular, G2/M cells completed mitosis, while G1 cells showed little or no movement. Lastly, cells stored in chronic hypoxia displayed an enhanced radiosensitivity when compared to acutely hypoxic cells. Possible reasons for these observations are discussed.     

The heterogeneity of the T2 glottic carcinoma and its local control probability after radiation therapy

The definition of T₂ glottic carcinoma permits heterogeneity, which is implied in the literature by the varying local control probability ranging from about 40% to 80% for these tumors. In a prospective series of 59 consecutive patients with T₂ glottic tumors, the local control probability has been evaluated for two hypothetical subdivisions, one with relatively small tumors and the other with tumors of larger volume. The local control probability at 2 years appears to be significantly different, 96% as opposed to 65 %, for the above subdivisions. Dose response analysis has been made. The T2 tumors with small volume have a flat response curve below 7000 rad, whereas tumors with larger volume appear to have responded better with doses above 7000 rad.     

食管、贲门癌切除食管胃吻合口并发症的回顾性分析

目的　探讨食管胃吻合口并发症减少的真正原因。方法　１９８４ 年６ 月至１９９７ 年６ 月共手术切除食管癌和贲门癌５ １１９ 例,将前７ 年（１９８４ 年至１９９１ 年） 和后６ 年（１９９１ 年至１９９７ 年） 分为Ａ、Ｂ二组进行对比研究。结果　吻合口瘘、吻合口狭窄和返流性食管炎的发生率,Ａ组分别为４－２％ 、４－８６％ 和１５－５ ％ 。Ｂ组分别为１－０１ ％ 、２－１３％ 和７－０３％ 。Ａ 组吻合口瘘的死亡率为３９－３５ ％ ,Ｂ组无吻合口瘘死亡。二组并发症相比较有显著性差异（ Ｐ＜ ０．０１） 。Ａ、Ｂ二组的吻合方法我重要改变,只是吻合部位从胸腔上移至颈部。结论　吻合口并发症下降的原因是吻合技术的提高,与吻合方法关系不大。颈部吻合的最大优点是降低了吻合口瘘的死亡率。     

Cardiac toxicity and edema

Anticancerdrug-induced cardiac toxicity has been recognized since the introduction and widespread use of the anthracycline derivative doxorubicin in the 1970's. Risk factors for cardiac toxicity have increased along with the development of multidisciplinary therapy, high-dose combination chemotherapy, and molecular-targeted therapy. Cardiac toxicity is now recognized as a common adverse effect. Cardiac toxicity as an adverse event caused by molecular targeted agents such as trastuzumab may lead to irreversible cardiac dysfunction. The developmental mechanism of cardiac toxicity has not been fully defined for any agent. At present, practical strategies include the evaluation of cardiac function before treatment and the monitoring of cardiac function during treatment to determine whether chemotherapy should be administered or withdrawn. Edema caused by molecular-targeted agents such as imatinib is considered a relatively new adverse event. Prompt and accurate differential diagnosis of edema is essential, followed by appropriate action. Currently, however, only symptomatic treatment is available. Future studies should attempt to elucidate the mechanisms of cardiac toxicity and edema associated with molecular-targeted agents, as well as develop new treatment strategies.     

An analysis of the severe complications of irradiation of carcinoma of the uterine cervix: treatment with intracavitary radium and parametrial irradiation

Between January 1967 and December 1974, 254 patients with carcinoma of the uterine cervix were treated with either intracavitary radium and parametrial irradiation or 2000 rad whole pelvis irradiation followed by intracavitary radium and parametrial irradiation. In general, these patients had tumors of relatively limited volume and vaginal and uterine anatomy that was favorable for intracavitary radium. Not all patients had a lymphangiogram performed prior to irradiation. Of those who did, only patients with negative lymphangiograms are included in this analysis. All patient had a minimum follow-up of four years. The absolute four year survival rate for this group of patients was 86%. Only 6.3% of patients died of disease. The incidence of severe complications was 7.5%. Complications were associated with a high number of milligram hours of radium plus a high dose of external irradiation, in combination with either asymmetry of the radium system and/or history of previous pelvic inflammatory disease, pelvic surgery, or diverticulosis.     

Toxicity of glutaminase in patients with advanced lymphoblastic leukaemia

Fifteen patients with relapsed lymphoblastic leukaemia were treated with a glutaminase isolated from Achromobacter sp. using this enzyme for the first time in combination with other drugs in the treatment of human leukaemia.Although two patients achieved complete remission, and a further three partial remission, five patients showed acute hypersensitivity to the glutaminase and two of the five required resuscitation. Also one patient developed hyperglycaemic ketoacidosis 36 h after receiving the enzyme for the first time, and three others had biochemical evidence of carbohydrate intolerance. All patients experienced nausea and vomiting shortly after the start of the first infusion which lessened with second and third courses, and did not necessitate withdrawal of the drug.The high incidence of side effects in these patients indicates that despite the anti-leukaemic activity of this enzyme its application is limited by poor patient acceptability.