***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND After breast-conserving surgery , 90 % of local recurrences occur within the index quadrant despite the presence of multicentric cancers elsewhere in the breast . Thus , restriction of radiation therapy to the tumour bed during surgery might be adequate for selected patients . We compared targeted intraoperative radiotherapy with the conventional policy of whole breast external beam radiotherapy . METHODS Having safely piloted the new technique of single-dose targeted intraoperative radiotherapy with Intrabeam , we launched the TARGIT-A trial on March 24 , 2000 . In this prospect i ve , r and omised , non-inferiority trial , women aged 45 years or older with invasive ductal breast carcinoma undergoing breast-conserving surgery were enrolled from 28 centres in nine countries . Patients were r and omly assigned in a 1:1 ratio to receive targeted intraoperative radiotherapy or whole breast external beam radiotherapy , with blocks stratified by centre and by timing of delivery of targeted intraoperative radiotherapy . Neither patients nor investigators or their teams were masked to treatment assignment . Postoperative discovery of predefined factors ( eg , lobular carcinoma ) could trigger addition of external beam radiotherapy to targeted intraoperative radiotherapy ( in an expected 15 % of patients ) . The primary outcome was local recurrence in the conserved breast . The predefined non-inferiority margin was an absolute difference of 2.5 % in the primary endpoint . All r and omised patients were included in the intention-to-treat analysis . This trial is registered with Clinical Trials.gov , number NCT00983684 . FINDINGS 1113 patients were r and omly allocated to targeted intraoperative radiotherapy  and 1119 were allocated to  external beam radiotherapy .  Of 996 patients who received the allocated treatment in the targeted intraoperative radiotherapy group , 854 ( 86 % ) received targeted intraoperative radiotherapy only and 142 ( 14 % ) received targeted intraoperative radiotherapy plus external beam radiotherapy . 1025 ( 92 % ) patients in the external beam radiotherapy group received the allocated treatment . At 4 years , there were six local recurrences in the intraoperative radiotherapy group and five in the external beam radiotherapy group . The Kaplan-Meier estimate of local recurrence in the conserved breast at 4 years was 1.20 % ( 95 % CI 0.53 - 2.71 ) in the targeted intraoperative radiotherapy and 0.95 % ( 0.39 - 2.31 ) in the external beam radiotherapy group ( difference between groups 0.25 % , -1.04 to 1.54 ; p=0.41 ) . The frequency of any complications and major toxicity was similar in the two groups ( for major toxicity , targeted intraoperative radiotherapy , 37 [ 3.3 % ] of 1113 vs external beam radiotherapy , 44 [ 3.9 % ] of 1119 ; p=0.44 ) . Radiotherapy toxicity ( Radiation Therapy Oncology Group grade 3 ) was lower in the targeted intraoperative radiotherapy group ( six patients [ 0.5 % ] ) than in the external beam radiotherapy group ( 23 patients [ 2.1 % ] ; p=0.002 ) . INTERPRETATION For selected patients with early breast cancer , a single dose of radiotherapy delivered at the time of surgery by use of targeted intraoperative radiotherapy should be considered as an alternative to external beam radiotherapy delivered over several weeks . FUNDING University College London Hospitals (UCLH)/UCL Comprehensive Biomedical Research Centre , UCLH Charities , National Institute for Health Research Health Technology Assessment programme , Ninewells Cancer Campaign , National Health and Medical Research Council , and German Federal Ministry of Education and Research ( BMBF ) PURPOSE To report interim cosmetic and toxicity results of a multicenter r and omized trial comparing accelerated partial-breast irradiation ( APBI ) using three-dimensional conformal external beam radiation therapy ( 3D-CRT ) with whole-breast irradiation ( WBI ) . PATIENTS AND METHODS Women age > 40 years with invasive or in situ breast cancer ≤ 3 cm were r and omly assigned after breast-conserving surgery to 3D-CRT APBI  ( 38.5 Gy in 10 fractions twice daily ) or WBI ( 42.5 Gy in 16 or 50 Gy in 25 daily fractions ± boost irradiation ) . The primary outcome was ipsilateral breast tumor recurrence ( IBTR ) . Secondary outcomes were cosmesis and toxicity . Adverse cosmesis was defined as a fair or poor global cosmetic score . After a planned interim cosmetic analysis , the data , safety , and monitoring committee recommended release of results . There have been too few IBTR events to trigger an efficacy analysis . RESULTS Between 2006 and 2011 , 2,135 women were r and omly assigned to 3D-CRT APBI or WBI . Median follow-up was 36 months . Adverse cosmesis at 3 years was increased among those treated with APBI compared with WBI as assessed by trained nurses ( 29 % v 17 % ; P < .001 ) , by patients ( 26 % v 18 % ; P = .0022 ) , and by physicians review ing digital photographs ( 35 % v 17 % ; P < .001 ) . Grade 3 toxicities were rare in both treatment arms ( 1.4 % v 0 % ) , but grade 1 and 2 toxicities were increased among those who received APBI compared with WBI ( P < .001 ) . CONCLUSION 3D-CRT APBI  increased rates of adverse cosmesis and late radiation toxicity compared with st and ard WBI . Clinicians and patients are caution ed against the use of 3D-CRT APBI outside the context of a controlled trial Between 1979–1987 , the National Cancer Institute conducted a r and omized , prospect i ve study of mastectomy ( MT ) versus breast conservation therapy ( BCT ) in the treatment of patients with early‐stage breast carcinoma . After a median potential follow‐up of 18.4 years , the authors present the up date d results Breast cancer multifocality was studied in mastectomy specimens by correlated specimen radiography and histologic techniques . The patients chosen for study were comparable to those eligible for breast‐conserving surgical therapy . Two study groups , one with 282 invasive cancers ( T1‐2 ) and the other with 32 intraductal cancers , were selected from a group of 399 consecutive cases by omitting patients who were clearly , or very probably , not c and i date s for breast‐conserving surgical therapy according to current trial criteria . Omitted patients included those with clinical ly and /or radiologically multifocal cancers and patients with tumor extension into the chest wall or skin ( 7 % ) . Also excluded were the socalled diffuse invasive cancers ( 8 % ) , the clinical ly and radiologically occult tumors ( 3 % ) , and the invasive cancers larger than 5 cm ( 3 % ) . Of the 282 invasive cancers , 105 ( 37 % ) showed no tumor foci in the mastectomy specimen around the reference mass . In 56 ( 20 % ) tumor foci were present within 2 cm , and in 121 ( 43 % ) tumor was found more than 2 cm from the reference tumor . In 75 ( 27 % ) the tumor foci beyond 2 cm were histologically noninvasive cancers , and in 46 cases ( 16 % ) they contained invasive cancers as well . A comparison between the group with reference tumors less than 2 cm and the group with reference tumors more than 2 cm in size showed no significant difference between the groups in terms of presence or absence of tumor foci or distance of tumor foci from the reference tumor . If the 264 invasive cancers in this series that were 4 cm or less in diameter had been removed with a margin of 3 to 4 cm , 7 % to 9 % of the patients would have had invasive cancer left in the remaining breast tissue , and 4 % to 9 % would have had foci of noninvasive cancer left in the remaining breast tissue . On the basis of the data on the distribution of tumor at different distances from the reference tumor , the current study estimates the expected rates of local recurrences after breast‐conserving surgical procedures relative to the extensiveness of the excision . The possible impact of postoperative local radiation therapy on the rates of expected local recurrence is discussed BACKGROUND AND PURPOSE To report the long-term results of a single-institution r and omized study comparing the results of breast-conserving treatment with partial breast irradiation ( PBI ) or conventional whole breast irradiation ( WBI ) . PATIENTS AND METHODS Between 1998 and 2004 , 258 selected women with pT1 pN0 - 1mi M0 , grade 1 - 2 , non-lobular breast cancer without the presence of extensive intraductal component and resected with negative margins were r and omized after BCS to receive 50 Gy WBI ( n=130 ) or PBI ( n=128 ) . The latter consisted of either 7 × 5.2 Gy high-dose-rate ( HDR ) multi-catheter brachytherapy ( BT ; n=88 ) or 50 Gy electron beam ( EB ) irradiation ( n=40 ) . Primary endpoint was local recurrence ( LR ) as a first event . Secondary endpoints were overall survival ( OS ) , cancer-specific survival ( CSS ) , disease-free survival ( DFS ) , and cosmetic results . RESULTS After a median follow up of 10.2 years , the ten-year actuarial rate of LR was 5.9 % and 5.1 % in PBI and WBI arms , respectively ( p=0.77 ) . There was no significant difference in the ten-year probability of OS ( 80 % vs 82 % ) , CSS ( 94 % vs 92 % ) , and DFS ( 85 % vs 84 % ) , either . The rate of excellent-good cosmetic result was 81 % in the PBI , and 63 % in the control group ( p<0.01 ) . CONCLUSIONS Partial breast irradiation delivered by interstitial HDR BT or EB for a selected group of early-stage breast cancer patients produces similar ten-year results to those achieved with conventional WBI . Significantly better cosmetic outcome can be achieved with HDR BT implants compared with the outcome after WBI BACKGROUND The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy ( TARGIT ) versus fractionated external beam radiotherapy ( EBRT ) for breast cancer . We report 5-year results for local recurrence and the first analysis of overall survival . METHODS TARGIT-A was a r and omised , non-inferiority trial . Women aged 45 years and older with invasive ductal carcinoma were enrolled and r and omly assigned in a 1:1 ratio to receive TARGIT or whole-breast EBRT , with blocks stratified by centre and by timing of delivery of targeted intraoperative radiotherapy : r and omisation occurred either before lumpectomy ( prepathology stratum , TARGIT concurrent with lumpectomy ) or after lumpectomy ( postpathology stratum , TARGIT given subsequently by reopening the wound ) . Patients in the TARGIT group received supplemental EBRT ( excluding a boost ) if unforeseen adverse features were detected on final pathology , thus radiotherapy was risk-adapted . The primary outcome was absolute difference in local recurrence in the conserved breast , with a prespecified non-inferiority margin of 2·5 % at 5 years ; prespecified analyses included outcomes as per timing of r and omisation in relation to lumpectomy . Secondary outcomes included complications and mortality . This study is registered with Clinical Trials.gov , number NCT00983684 . FINDINGS Patients were enrolled at 33 centres in 11 countries , between March 24 , 2000 , and June 25 , 2012 . 1721 patients were r and omised to TARGIT and 1730 to EBRT .  Supplemental EBRT after TARGIT was necessary in 15·2 % [ 239 of 1571 ] of patients who received TARGIT ( 21·6 % prepathology , 3·6 % postpathology ) . 3451 patients had a median follow-up of 2 years and 5 months ( IQR 12 - 52 months ) , 2020 of 4 years , and 1222 of 5 years . The 5-year risk for local recurrence in the conserved breast was 3·3 % ( 95 % CI 2·1 - 5·1 ) for TARGIT versus 1·3 % ( 0·7 - 2·5 ) for EBRT ( p=0·042 ) . TARGIT concurrently with lumpectomy ( prepathology , n=2298 ) had much the same results as EBRT : 2·1 % ( 1·1 - 4·2 ) versus 1·1 % ( 0·5 - 2·5 ; p=0·31 ) . With delayed TARGIT ( postpathology , n=1153 ) the between-group difference was larger than 2·5 % ( TARGIT 5·4 % [ 3·0 - 9·7 ] vs EBRT 1·7 % [ 0·6 - 4·9 ] ; p=0·069 ) . Overall , breast cancer mortality was much the same between groups 
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We found no data for the outcomes of acute toxicity , new ipsilateral breast primaries , costs , quality of life or consumer preference .
The limitations of the data currently available mean that we can not make definitive conclusions about the efficacy and safety or ways to deliver of PBI/APBI .