Hypofractionated Radiation Therapy With Concomitant Boost in Treating Women After Breast Conserving Surgery

Inclusion Criteria: * female, aged between 18-70 * pathological confirmed breast invasive carcinoma * patients after breast lumpectomy(including quadrantectomy) with axillary lymph nodes dissection or sentinel node biopsy * stage p T 1-2 N 0 * metastasis omitted by routine examinations in 1 months before enrollment * complete blood count obtained in 2 weeks prior to study entry should meet the following criteria: absolute neutrophil count \> 1.8 \*10\^9/L, hemoglobin \> 8.0g/dl, platelet \> 75 \* 10\^9/L * hepatic and renal function in 2 weeks prior to study entry should be normal * study entry within 60 days from whichever comes later: surgery or last chemotherapy * women of childbearing potential must have a negative urine or serum pregnancy test with 2 weeks of study entry * signs study specific informed consent prior to study entry Exclusion Criteria: * breast cancer with stage III/III (AJCC 7th) * occult breast cancer * in-situ breast carcinoma * bilateral breast cancer * male breast cancer * breast lymphoma or breast sarcoma * combined with Paget's disease * received preoperative treatment(including neoadjuvant chemotherapy, endocrine therapy and target therapy * positive surgical margin * axillary lymph nodes dissection or sentinel lymph node biopsy omitted * regional lymph nodes radiation needed * boost volume larger than 1/4 of the whole breast * tumor bed unable to recognize on CT * prior invasive malignant tumor history * prior radiation to thoracic * connective tissue disease, such as active systemic lupus erythematosus and scleroderma, etc. * severe, active co-morbidity, defined as follows: * unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months * severe, acute bacterial or fungal infection within the last 2 weeks * chronic obstructive pulmonary disease exacerbation or other respiratory illness within 30 days * pregnant women