- 期刊
- OpenAccess
Dose Uniformity for the Triangle between Tangential Fields and Internal Mammary Field in Breast Preservation Therapy
在乳房保存治療法中使相切照野與正向內乳照野之三角區域劑量均勻之新治療技術
摘要
在乳癌乳房保留治療法中，當原發腫瘤位於乳房內側且合併腋下淋巴轉移及一正向內乳照野時，放射治療技術如果使用一對相切照野時，會在相接的三角區域內產生低劑量區；而此區卻正好是腫瘤之高復發區。因此本文所要發表的新放射治療技術，乃是利用兩對不成180度之相切照野及兩個寬度不同之斜向內乳照野。合成兩種照射組合以使得此低劑量區接受足夠且較均勻之劑量。以10位乳癌病人之治療用電腦斷層資料分析，此新治療技術在乳房內側會產生一約5~6公分寬之相對高劑量區（高約10~20%）。對於原發腫瘤於乳房內側者，此相對高劑量區還可以用來做為加強劑量且不致於引起乳房之變形。
並列摘要
In radiation treatment for breast cancer patients who have inner quadrant tumors and positive axillary lymph nodes, an underdosed triangle exists between the breast tangential fields and the en face internal mammary field. This triangle, within the region of high risk for recurrence, usually receives only a suboptimal dose of radiation. A new breast radiation technique has thus been developed using multiple angles of gantry for the tangential fields to give adequate and uniform dose distributions between the tangential fields and the separate internal mammary field. This technique combines two oblique internal mammary fields and two sets of opposed tangential fields with an angle greater than 180 degrees; it can offer the under- dosed triangle in the field junction a better homogeneity in dose distribution. Other radiation techniques are also reviewed for comparision with this new technique.