***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: OBJECTIVE The purpose of this study was to evaluate the safety and performance of localizing nonpalpable breast lesions using radiofrequency identification technology . SUBJECTS AND METHODS Twenty consecutive women requiring preoperative localization of a breast lesion were recruited . Subjects underwent placement of both a hook wire and a radiofrequency identification tag immediately before surgery . The radiofrequency identification tag was the primary method used by the operating surgeon to localize each lesion during excision , with the hook wire serving as backup in case of tag migration or failed localization . Successful localization with removal of the intended lesion was the primary outcome measured . Tag migration and postoperative infection were also noted to assess safety . RESULTS Twenty patients underwent placement of a radiofrequency identification tag , 12 under ultrasound guidance  and eight with stereotactic guidance .  In all cases , the radiofrequency identification tag  was successfully localized by the reader at the level of the skin before incision , and the intended lesion was removed along with the radiofrequency identification tag . There were no localization failures and no postoperative infections . Tag migration did not occur before incision , but in three cases , occurred as the lesion was being retracted with fingers to make the final cut along the deep surface of the specimen . CONCLUSION In this initial clinical study , radiofrequency tags were safe and able to successfully localize nonpalpable breast lesions . Radiofrequency identification technology may represent an alternative method to hook wire localization Purpose Regional axillary lymph node status has remained the single most independent variable to predict prognosis both in terms of disease recurrence and survival . This study aim ed to prospect ively assess sequential [18F]fluorodeoxyglucose ( FDG ) positron emission tomography ( PET ) findings as early predictors of axillary lymph node response to neoadjuvant chemotherapy in stage II and III breast cancer patients . Methods Images were acquired with a PET/CT scanner in 52 patients after administration of FDG ( 5 MBq/kg ) at baseline and after the first , second , third and sixth course of chemotherapy before surgery . Clinical examination and ultrasound ( US ) were used to assess the size of axillary nodes . Decrease in the st and ardized uptake value ( SUV ) with PET corrected or not for partial volume effects was compared to the pathological response . Results The sensitivity , specificity and accuracy of axillary node staging was higher with PET ( 75 , 87 and 80 % ) than with US ( 50 , 83 and 65 % ) , and even more so when PET images were corrected for partial volume effects ( 86 , 83 and 84 % ) . While FDG uptake did not vary much in non-responders , as confirmed by histopathological analysis , it markedly decreased to baseline levels in responders ( p < 10−5 ) . Fifty per cent of baseline SUV was considered the best cutoff value to distinguish responders from non-responders . The sensitivity , specificity , negative predictive value and accuracy of FDG PET  after one course of chemotherapy were , respectively , 96 , 75 , 95 and 84 % . Conclusion The pathological status of regional axillary lymph nodes in stage II and III breast cancer patients could be accurately predicted after one course of neoadjuvant chemotherapy based on FDG PET images BACKGROUND With the growing importance of neoadjuvant systemic therapy ( NST ) the assessment of post neoadjuvant axillary status is of increasing importance especially in patients who presented initially with suspicious nodes ( cN1 ) . This study aims to investigate the predictive value of  palpation and axillary ultrasound  of formerly cN1 patients following NST . PATIENTS AND METHODS The SENTINA trial ( SENTinel NeoAdjuvant ) is a 4-arm prospect i ve multicenter study design ed to evaluate the role of sentinel node biopsy ( SLNB ) in the context of neoadjuvant systemic treatment ( NST )  of breast cancer patients . RESULTS 1240 patients from 103 institutions entered the trial . 715 ( arm C n = 592 ; arm D n = 123 ) patients , who presented initially cN1 underwent clinical evaluation of lymph node status following  NST . Palpation alone demonstrated a sensitivity of 8.3 % , specifity of 94.8 % and a negative predictive value ( NPV ) of 46.6 % . Ultrasound alone revealed a sensitivity of 23.9 % , specificity 91.7 % , and a NPV of 50.3%.The investigators combined classification ( palpation and ultrasound ) result ed in a sensitivity of 24.4 % , specificity 91.4 % , and a NPV of 50.3 % . Investigators classified the axilla nodes as being unsuspicious ( cN0 ) following NST in 592/715 patients ; of them 298 ( 50.3 % ) were pN0 , 151 ( 25.5 % ) had 1 - 2 histologically involved nodes and 143 ( 24.2 % ) had > 2 histologically involved nodes . CONCLUSION The diagnostic accuracy of ultrasound and palpation following NST is unacceptably low and additional tools for evaluation of the axillary lymph node status following NST are urgently needed Background Recent trials have suggested the feasibility of performing a sentinel lymph node biopsy ( SNB ) following neoadjuvant chemotherapy ( NAC ) . The selection of suitable patients for this approach remains controversial . We developed a predictive model to identify patients most likely to benefit from SNB following  NAC . Methods The National Cancer Data Base was used to identify patients with clinical ly node positive ( cN+ ) breast cancer undergoing NAC followed by breast surgery and axillary lymph node dissection ( ALND ) .  Patients were r and omly assigned to a 70 % testing or 30 % validation cohort for model development . A predictive model was built based on significant factors associated with pathologic nodal response ( pN0 ) and breast response . Results Using the testing cohort ( n = 13,396 ) , multivariate regression was used to identify predictors of pN0 based on preoperative factors . Younger age , hormone receptor (HR)-negative/Her2-negative , HR-positive/Her2-positive , HR-negative/Her2-positive , high- grade , ductal histology , cN1 versus cN2 , and extent of breast response were all significant independent predictors of pN0 on adjusted analysis . The odds ratios translated into a 10-point scale correlating to a stepwise increase in pN0 response . The area under the curve for the ROC curves for the testing and validation cohorts was 0.781 and 0.788 , respectively ( p < 0.01 ) . Conclusions Our model incorporates known preoperative factors to predict the likelihood of pN0 response in patients with cN+ disease who undergo  NAC .  For patients with high scores , SNB should be considered over ALND , because these patients have a greater likelihood of having negative nodes at final pathology BACKGROUND If treatment of the axilla is indicated in patients with breast cancer who have a positive sentinel node , axillary lymph node dissection is the present st and ard . Although axillary lymph node dissection provides excellent regional control , it is associated with harmful side-effects . We aim ed to assess whether axillary radiotherapy provides comparable regional control with fewer side-effects . METHODS Patients with T1 - 2 primary breast cancer and no palpable lymphadenopathy were enrolled in the r and omised , multicentre , open-label , phase 3 non-inferiority EORTC 10981 - 22023 AMAROS trial . Patients were r and omly assigned ( 1:1 ) by a computer-generated allocation schedule to receive either axillary lymph node dissection or axillary radiotherapy in case of a positive sentinel node , stratified by institution . The primary endpoint was non-inferiority of 5-year axillary recurrence , considered to be not more than 4 % for the axillary radiotherapy group compared with an expected 2 % in the axillary lymph node dissection group . Analyses were by intention to treat and per protocol . The AMAROS trial is registered with Clinical Trials.gov , number NCT00014612 . FINDINGS Between Feb 19 , 2001 , and April 29 , 2010 , 4823 patients were enrolled at 34 centres from nine European countries , of whom 4806 were eligible for r and omisation . 2402 patients were r and omly assigned to receive  axillary lymph node dissection and 2404 to receive axillary radiotherapy . Of the 1425 patients with a positive sentinel node , 744 had been r and omly assigned to axillary lymph node dissection and 681 to axillary radiotherapy ; these patients constituted the intention-to-treat population . Median follow-up was 6·1 years ( IQR 4·1 - 8·0 ) for the patients with positive sentinel lymph nodes . In the axillary lymph node dissection group , 220 ( 33 % ) of 672 patients who underwent axillary lymph node dissection had additional positive nodes . Axillary recurrence occurred in four of 744 patients in the axillary lymph node dissection group and seven of 681 in the axillary radiotherapy group . 5-year axillary recurrence was 0·43 % ( 95 % CI 0·00 - 0·92 ) after axillary lymph node dissection versus 1·19 % ( 0·31 - 2·08 ) after axillary radiotherapy . The planned non-inferiority test was underpowered because of the low number of events . The one-sided 95 % CI for the underpowered non-inferiority test on the hazard ratio was 0·00 - 5·27 , with a non-inferiority margin of 2 . Lymphoedema in the ipsilateral arm was noted significantly more often after axillary lymph node dissection than after axillary radiotherapy at 1 year , 3 years , and 5 years . INTERPRETATION Axillary lymph node dissection and axillary radiotherapy after a positive sentinel node provide excellent and comparable axillary control for patients with T1 - 2 primary breast cancer and no palpable lymphadenopathy . Axillary radiotherapy results in significantly less morbidity . FUNDING EORTC Charitable Trust Purpose To provide current recommendations on the use of sentinel node biopsy ( SNB ) for patients with early-stage breast cancer . Methods PubMed and the Cochrane Library were search ed for r and omized controlled trials , systematic review s , meta-analyses , and clinical practice guidelines from 2012 through July 2016 . An Up date Panel review ed the identified abstract s. Results Of the eight publications identified and review ed , none prompted a change in the 2014 recommendations , which are reaffirmed by the up date d literature review . Conclusion Women without sentinel lymph node ( SLN ) metastases should not receive axillary lymph node dissection ( ALND ) . Women with one to two metastatic SLNs who are planning to undergo breast-conserving surgery with whole-breast radiotherapy should not undergo ALND ( in most cases ) . Women with SLN metastases who will undergo mastectomy should be offered ALND . These three recommendations are based on r and omized controlled trials . Women with operable breast cancer and multicentric tumors , with ductal carcinoma in situ , who will undergo mastectomy , who previously underwent breast and /or axillary surgery , or who received preoperative/neoadjuvant systemic therapy may be offered SNB .  Women who have large or locally advanced invasive breast cancer ( tumor size T3/T4 ) , inflammatory breast cancer , or ductal carcinoma in situ ( when breast-conserving surgery is planned ) or are pregnant should not undergo SNB Background Neoadjuvant chemotherapy ( NAC ) downstages axillary disease in 55 % of node-positive ( N1 ) breast cancer . The feasibility and accuracy of sentinel lymph node biopsy ( SLNB ) after NAC for percutaneous biopsy-proven N1 patients who are clinical ly node negative ( cN0 ) by physical examination after NAC is under investigation . ACOSOG Z1071 reported a false-negative rate of < 10 % if ≥3 nodes are removed with dual tracer , including excision of the biopsy-proven positive lymph node ( BxLN ) . We report our experience using radioactive seed localization ( RSL ) to retrieve the BxLN with SLNB ( RSL/SLNB ) for cN0 patients after NAC . Methods We performed a retrospective review of a single-institution , prospect ively maintained registry for the years 2013 to 2014 . Patients with BxLN who received NAC and had RSL/SLNB were identified . All BxLNs were marked with a radiopaque clip before NAC to facilitate RSL . Results Thirty patients with BxLN before NAC were cN0 after NAC  and underwent RSL/SLNB .  Median age was 55 years . Disease stage was IIA – IIIB . Twenty-nine of 30 had ductal cancer ( 12 triple negative and 16 HER-2 positive ) . One to 11 nodes were retrieved . Twenty-nine of 30 BxLN were successfully localized with RSL . Note was made of the BxLN-containing isotope and /or dye in 22 of 30 . Nineteen patients had no residual axillary disease ; 11 had persistent disease . All who remained node positive had disease in the Bx 
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The diagnostic performance of ultrasound after NAT seems to be associated with tumor subtype : the positive predictive value was highest in luminal , the negative in triple-negative tumors .
Conclusion In conclusion , ultrasound improves prediction of axillary response to treatment in comparison to physical examination and serves as a reliable guiding tool for marking of target lymph nodes before the start of treatment .