乳癌四分之一野与单中心技术.doc

1.文章在90年代初出现（国内2000年后），03年参加放疗标准化临床试验，06、08、09年还有技术改进文章
(Published Online August 21 2006)
Original Article

An evaluation of three tangential breast irradiation techniques in Hong Kong

Maria Y.Y. Law a1c1, Fion W.K. Cheung a1, Vincent W.C. Wu a1, Venus W.C. Tsang a1, Rainnie W.Y. Kwan a1, Johnny Y.T. Cheng a1 and Fatson K.F. Wong a1
a1 Department of Optometry and Radiography, Hong Kong Polytechnic University, Hong Kong
Article author query
law my   [PubMed] [Google Scholar] 
cheung fw   [PubMed] [Google Scholar] 
wu vw   [PubMed] [Google Scholar] 
tsang vw   [PubMed] [Google Scholar] 
kwan rw   [PubMed] [Google Scholar] 
cheng jy   [PubMed] [Google Scholar] 
wong fk   [PubMed] [Google Scholar] 

Abstract
Background and Purpose: Loco-regional radiotherapy after breast conserving surgery significantly reduces the risk of recurrence but may induce complications in the lungs. The complications are related to the lung volume irradiated and the lung dose delivered. The purpose of this study was to evaluate three tangential breast irradiation techniques i.e. conventional technique, gantry tilting technique and half-beam block technique in terms of the percentage of irradiated lung volume and high dose lung volume for patients of different sizes.
Materials and Method: Treatment planning of the three tangential breast irradiation techniques was performed using the CT scans of 20 patients with early-stage breast cancer after lumpectomy.
Results: When compared with conventional technique, both half beam block technique and gantry tilting technique irradiated a significantly smaller percentage of lung volume and delivered a smaller percentage of high dose (above 30 Gy) volume in the lung. Patients with large breasts had a significantly higher percentage of lung volume irradiated to above 30Gy than those patients with small and medium breasts. The combined effect of tangential separation and technique only produced significant effect on the percentage of total lung volume irradiated but not on the high dose volume.
Conclusions: Gantry tilting and half-beam block techniques can reduce a significant amount of lung volume and high dose lung volume. Half-beam block technique is recommended for small and medium breast size while for large breast size, gantry tilting technique is preferred.
###【2006 online：】
Journal of Radiotherapy in Practice (2000), 2:1:9-15 Cambridge University Press
Copyright © 2000 Cambridge University Press
doi:10.1017/S1460396900000030

Original Article

An evaluation of three tangential breast irradiation techniques in Hong Kong

Maria Y.Y. Law a1c1, Fion W.K. Cheung a1, Vincent W.C. Wu a1, Venus W.C. Tsang a1, Rainnie W.Y. Kwan a1, Johnny Y.T. Cheng a1 and Fatson K.F. Wong a1
a1 Department of Optometry and Radiography, Hong Kong Polytechnic University, Hong Kong
Article author query
law my   [PubMed] [Google Scholar] 
cheung fw   [PubMed] [Google Scholar] 
wu vw   [PubMed] [Google Scholar] 
tsang vw   [PubMed] [Google Scholar] 
kwan rw   [PubMed] [Google Scholar] 
cheng jy   [PubMed] [Google Scholar] 
wong fk   [PubMed] [Google Scholar] 

Abstract
Background and Purpose: Loco-regional radiotherapy after breast conserving surgery significantly reduces the risk of recurrence but may induce complications in the lungs. The complications are related to the lung volume irradiated and the lung dose delivered. The purpose of this study was to evaluate three tangential breast irradiation techniques i.e. conventional technique, gantry tilting technique and half-beam block technique in terms of the percentage of irradiated lung volume and high dose lung volume for patients of different sizes.
Materials and Method: Treatment planning of the three tangential breast irradiation techniques was performed using the CT scans of 20 patients with early-stage breast cancer after lumpectomy.
Results: When compared with conventional technique, both half beam block technique and gantry tilting technique irradiated a significantly smaller percentage of lung volume and delivered a smaller percentage of high dose (above 30 Gy) volume in the lung. Patients with large breasts had a significantly higher percentage of lung volume irradiated to above 30Gy than those patients with small and medium breasts. The combined effect of tangential separation and technique only produced significant effect on the percentage of total lung volume irradiated but not on the high dose volume.
Conclusions: Gantry tilting and half-beam block techniques can reduce a significant amount of lung volume and high dose lung volume. Half-beam block technique is recommended for small and medium breast size while for large breast size, gantry tilting technique is preferred.
(Published Online August 21 2006)

Key Words: Breast cancer; radiotherapy technique; tangential irradiation.

Correspondence:
c1 Correspondence to: Maria Law, Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong. E-mail: [e-mail]
« PreviousNext »International Journal of Radiation Oncology * Biology * Physics
Volume 19, Issue 4 , Pages 1037-1040, October 1990
A nondivergent three field matching technique for breast irradiation
窗体顶端

· James C.H. Chu, Ph.D.
AFFILIATIONS
· Reprint requests to; James C. H. Chu, Ph.D., Department of Radiation Oncology, Fox Chase Cancer Center, 7701 Burholme Ave., Philadelphia, PA 19111.
,
· Lawrence J. Solin, M.D.,
· Chin Chang Hwang, M. S.,
· Barbara Fowble, M.D.,
· Gerald E. Hanks, M.D.,
· Robert L. Goodman, M.D.
窗体底端
Accepted 26 April 1990.
· Abstract
· Abstract + References
· PDF
· References
Abstract 
Effective radiation therapy to intact breasts requires the delivery of adequate dose to a large target volume using complex beam arrangements. A semi-empirical method is described to determine the correct gantry, collimator, and couch positions for a geometrically accurate field match among adjoining radiation beams. The technique uses a metal rod and chain combination to aid determination of the proper couch setting under remote fluoroscopy control. A couch position error of more than half a degree is easily detectable by this technique.
Keywords: Breast irradiation, Field matching
TECHNICAL NOTE
A virtual matching technique for three-field breast irradiation using 3-D planning

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Jonathan B. Straussa, , , Michael C. Kirka, 1, Sea S. Chena, Anand P. Shaha, Benjamin T. Gieldaa, James C. Chua, Julius V. Turiana and Adam Dicklerb
aRush University Medical Center, Department of Radiation Oncology, Chicago, IL 60612, USA
bLittle Company of Mary Hospital, Department of Radiation Oncology, Evergreen Park, IL 60805, USA
Received 1 August 2008; 
revised 10 January 2009; 
accepted 3 March 2009. 
Available online 3 April 2009.

Abstract
Patients with breast cancer are often treated with radiation to the breast (or chest wall) and draining regional lymph nodes. This is typically performed with a three-field technique in which an anterior supraclavicular field is matched to opposed tangent fields. A single isocenter technique is not always possible. Several techniques have been described to create a perfect match using a conventional simulator. We describe and test a simple, fast and accurate technique to estimate the couch and collimator angles required for a perfect geometric match using 3-D treatment planning software. This method requires no mathematical formulae and is verifiable relative to patient anatomy.
An external skin contour is created on the axial slice at the match line and displayed with a 3-D representation. Using a beam's eye view (BEV) of a tangent field, small couch and collimator rotation adjustments are made sequentially until the contour edges are superimposed. The virtual external contour technique was easy to use, gave verification of the match in the BEV and yielded estimates of couch and collimator rotations very close to those calculated using published formulae.
Keywords: Breast cancer; Radiation; Field matching; Three-field technique
Article Outline
Introduction
Technique
Simulation
Treatment planning
Example
Results
Discussion
References

2.四分之一野的剂量匹配好（而转床的剂量匹配差些）定位要求高：
胶片剂量验证
1: Int J Radiat Oncol Biol Phys. 1994 Feb 1;28(3):753-60. Links
A mono isocentric technique for breast and regional nodal therapy using dual asymmetric jaws.单个等中心及不对称野的乳腺及区域淋巴结治疗技术
Klein EE, Taylor M, Michaletz-Lorenz M, Zoeller D, Umfleet W.
Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, MO 63110.
PURPOSE: Definitive radiation therapy for breast cancer with regional nodal involvement often introduces treatment of adjacent abutted regions. Many methods describe techniques to achieve an effective transverse plane match. Our facility recently adopted a matching technique using asymmetric jaws to beam-split all portals along the central axis plane. Our technique uses one isocenter to treat the opposed tangential breast fields, the supraclavicular port and the posterior axillary field.
METHODS AND MATERIALS: Our linear accelerator has four collimator jaws capable of being set independently. The longitudinal (Y) jaws beam-split all the portals at the match plane, namely the upper border of the tangential beams and the bottom border of the nodal fields. The transverse (X) jaws define the lateral borders of the nodal fields, and in a near beam-split fashion in conjunction with customized Cerrobend, block the lung for the tangential beams. The unique isocenter is chosen along the mid-bridge through the tangential match plane. Dosimetric qualities and calculational techniques of the asymmetric beams were analyzed with ionimetric water scans, ion chamber studies, and film. The match-line is clinically confirmed with composite port films.
RESULTS:
1）Our dosimetric studies show asymmetric jaws provide nearly equivalent field edge definition and superior absorption in comparison with Cerrobend blocks. The use of one isocenter results in a reduction of in-room treatment time by a factor of two. The burden of lifting heavy Cerrobend blocks has been removed. A composite port film, which includes the medial tangential and supraclavicular ports, shows a perfect match-line in all cases. （胶片剂量测量表明切线野与锁骨上野得到完全匹配）
2）Similar composite port films taken with our previous technique of geometric matching with collimator and table angulation exhibit slight overlap or underdose regions in many cases（转床的剂量匹配略差，常有些过或欠剂量）.
CONCLUSION: Our treatment technique takes full advantage of dual asymmetric jaws （四分之一野）to achieve a perfect match-line, necessitates only one isocenter and set-up point, and supplies more absorption in reference to lung and contralateral breast dose. The pure match-line is accompanied by the fact that the patient does not have to move in any direction.（理想的匹配线要求病人不得移动）
PMID: 8113122 [PubMed - indexed for MEDLINE]
3）找原文-四分之一野
1: Int J Radiat Oncol Biol Phys. 1990 Jul;19(1):183-8
###A technique for treating local breast cancer using a single set-up point and asymmetric collimation.
Rosenow UF, Valentine ES, Davis LW.
Department of Radiation Oncology, Albert Einstein College of Medicine, NY, NY.
Using both pairs of asymmetric jaws of a linear accelerator local-regional breast cancer may be treated from a single set-up point. This point 是位于匹配线处is placed at the abutment of the supraclavicular fields with the medial and lateral tangential fields. Positioning the jaws to create a half-beam superiorly permits treatment of the supraclavicular field. Positioning both jaws asymmetrically at midline to define a single beam in the inferoanterior quadrant（四分之一野） permits treatment of the breast from medial and lateral tangents. The highest possible matching accuracy （最高的匹配精度）between the supraclavicular and tangential fields is inherently provided by this technique. For treatment of all fields at 100 cm source to axis distance (SAD) the lateral placement and depth of the set-up point may be determined by simulation and simple trigonometry. We elaborate on the clinical procedure. For the technologists treatment of all fields from a single set-up point is simple and efficient（对技术员而言，所有野只用一个等中心更简单有效）. Since the tissue at the superior border of the tangential fields is generally firmer than in mid-breast（由于切线野的上边界与中部乳房相比是更固定）, greater accuracy in day-to-day set-up is permitted（重复定位更准确）. This technique eliminates the need for table angles even when tangential fields only are planned（无需转床）. Because of half-beam collimation the limit to the tangential field length is 20 cm. Means will be suggested to overcome this limitation in the few cases where it occurs. Another modification is suggested for linear accelerators with only one independent pair of jaws.
PMID: 2380084 [PubMed - indexed for MEDLINE]
4）
1: Med Dosim. 1994 Summer;19(2):107-10. Links
Three-field breast irradiation technique using tangential quarter fields.
Li C, Torigoe EW, Dunning A, Halberg F, Evans R.
Radiation Oncology Department, Marin General Hospital, Greenbrae, CA 94904.
We have developed and implemented in clinical practice an isocentric three-field breast irradiation technique using tangential quarter fields. In this technique, the same isocenter is used for the supraclavicular and the tangential breast fields. The superior-posterior corner of the tangential breast fields is placed at the central axis by asymmetric collimation of both the length and the width of the field. Consequently, the beam divergence at both the superior and posterior edges is eliminated, allowing a perfect geometric match between the posterior borders of both tangential breast fields and the supraclavicular field without table rotation. Compared to conventional techniques requiring table rotations, the present method produces a more uniform dose distribution in the target volume and requires significantly less simulation time（此技术在靶体积内产生更均匀的剂量,模拟定位的时间减少）.
PMID: 7916976 [PubMed - indexed for MEDLINE]
5）四分之一野
1: Radiother Oncol. 1993 Sep;28(3):228-32. Links
Three-field isocentric breast irradiation using asymmetric jaws and a tilt board.
Marshall MG.
Department of Radiology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157-1088.
Perfect abutment of medial and lateral tangential breast portals with the adjacent supraclavicular field may be achieved with ease. A simple and safe approach was developed using a tilt board and new technology that is standard on a popular linear accelerator. The patient is secured on a tilt board as a means to level the chest wall. Isocenter is placed at depth on the matchline, where asymmetric jaws are used to produce non-divergent field edges and a perfect abu