***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 The aim was to prove the low identification rate of sentinel lymph node biopsy ( SNB ) and to determine the feasibility of replacing axillary lymph node dissection ( AND ) in axillary lymph node positive patients after chemotherapy .  Methods From October 2001 to July 2005 , 875 consecutive patients with primary operable breast cancer underwent SNB and AND .  Among them , 238 received pre-operative chemotherapy .  We compared the identification rate , false negative rate ( FNR ) , negative predictive value ( NPV ) , and accuracy of  SNB  in clinical ly node-positive patients with or without chemotherapy .  Results The identification rate was significantly lower in patients received chemotherapy ( 77.6 % ) than in those not received it ( 97.0 % ) ( P < 0.001 ) . In those received the therapy , the FNR was 5.6 % , the NPV was 86.8 % , and the accuracy was 95.9 % . In those not received therapy , the FNR was 7.4 % and the accuracy was 92.6 % ( differences not statistically significant ) . Conclusion The identification rate in confirmed axillary lymph node-positive patients was significantly lower in patients received pre-operative chemotherapy , but accuracy did not differ significantly between the two groups . Thus , for patients who achieve complete axillary clearance by chemotherapy , SNB could replace AND PURPOSE To determine the detection rate , the false-negative rate , and the accuracy of sentinel lymph node ( SLN ) detection after neoadjuvant chemotherapy ( NAC ) for advanced breast cancer . PATIENTS AND METHODS A prospect i ve multicentric study was initiated to evaluate the results of  SLN biopsy with the combined method after NAC for advanced large operable breast cancer . RESULTS From September 2003 to March 2007 , 195 patients enrolled from 12 institutions were found suitable for evaluation . The detection rate was 90 % ( 176 of 195 patients ) , and the false-negative rate was 11.5 % ( six of 52 patients ) . Patients without axillary palpable nodes ( N0 ) before NAC had a better detection rate compared with patients with axillary suspicious nodes ( N1 , 94.6 % v 81.5 % ; P = .008 ) . The false-negative rate was not correlated with clinical nodal status before NAC ( 9.4 % v 15 % ; P = .66 ) . CONCLUSION This study confirms the feasibility of SLN biopsy after NAC in the case of large operable breast cancer . The detection rate , false-negative rate , and accuracy do not differ from those obtained in the case of early breast cancer without NAC , thus demonstrating the feasibility of SLN biopsy after NAC Abstract Background : We evaluated the accuracy of sentinel lymph node dissection ( SLND ) in patients with stage II and III breast cancer who had received preoperative therapy . Methods : A prospect i ve clinical trial evaluated 122 patients who had SLND followed by axillary lymph node dissection . Thirty-two women had stage II or III breast cancer and received preoperative doxorubicin-based chemotherapy or paclitaxel and radiotherapy .  Results : A sentinel lymph node ( SLN ) was identified in 31 ( 97 % ) of 32 patients . The SLN predicted the status of the axillary nodes in 30 ( 97 % ) of 31 patients . Eighteen ( 58 % ) of 31 had metastases in the SLN . Eighteen of 19 patients with axillary metastases had a tumor-positive SLN ( sensitivity , 95 % ; false-negative rate , 5 % ) . Eight ( 44 % ) of 18 women with metastases in the SLN also had metastases in 1 or more nonsentinel nodes . Conclusions : In this relatively small study , the accuracy of SLND in women with stage II or III breast cancer treated with preoperative therapy was similar to that achieved in early-stage breast cancer . If these results are confirmed in a larger cohort , it may be feasible to substitute SLND for routine axillary lymph node dissection in this population . This approach could reduce the morbidity of surgical therapy while preserving the accuracy of axillary staging and maintaining regional control in this high-risk population Abstract Background : Sentinel lymph node dissection ( SLND ) for small , early-stage breast cancer is well accepted . However , the role of SLND for large primary breast cancer is controversial . We investigated the feasibility and clinical applicability of SLND in patients with large ( ≥5 cm ) breast cancers and clinical ly negative axillae . Methods : A prospect ively entered data base was used to identify all patients who underwent surgical management of histopathologically confirmed primary breast carcinomas ≥5 cm in diameter between September 1991 and August 2000 . Patients who had clinical ly negative axillae and underwent SLND followed by completion axillary lymph node dissection ( ALND ) were selected for the study . The positivity rate , accuracy rate , and false-negative rate of SLND  were determined . Results : Of the 41 patients selected for the study , 24 had infiltrating ductal carcinoma and 17 had infiltrating lobular carcinoma .  Mean tumor size was 7.12 cm ( range , 5–23 cm ) . At least one sentinel lymph node ( SLN ) was identified in all cases . Thirty patients had tumor-positive SLNs . Axillary metastasis was also identified in one patient who did not have a positive SLN . Thus , SLN status accurately predicted regional nodal status in 98 % ( 40 of 41 ) of cases . The false-negative rate of SLND  was 3 % ( 1 of 31 ) . None of the three patients with SLN micrometastasis , defined as a tumor focus ≤2 mm , had tumor deposits in nonsentinel axillary lymph nodes . Only SLN macrometastasis ( > 2-mm tumor deposit ) and primary tumor size ≥7 cm predicted nonsentinel axillary metastasis with significance on multivariate analysis ( P = .008 and P = .046 , respectively ) . Conclusions : SLND is feasible and accurate in patients with large breast cancers and clinical ly negative axillae . Axillary lymph node dissection can be avoided in nearly one third of patients by focused examination of the SLN Background : In a prospect i ve study , upper limb morbidity and perceived disability/activities of daily life ( ADLs ) were assessed before and 1 year after  sentinel lymph node biopsy ( SLNB ) or axillary lymph node dissection ( ALND ) . Methods : A total of 204 patients with stage I/II breast cancer ( mean age , 55.6 years ; SD , 11.6 years ) entered the study , and 189 patients ( 93 % ) could be evaluated after 1 year . Fifty-eight patients ( 31 % ) underwent only SLNB , and 131 ( 69 % ) underwent ALND . Assessment s performed before surgery ( t0 ) and 1 year after surgery ( t1 ) , included pain , shoulder range of motion , muscle strength , upper arm/forearm circumference , and perceived shoulder disability/ADL . Results : Considerable treatment-related upper limb morbidity was observed . Significant ( P < .05 ) changes between t0 and t1 were found in all assessment s except strength of elbow flexors . Patients in the ALND group showed significantly more changes in the range of motion in forward flexion , abduction , and abduction/external rotation ; grip strength and strength of shoulder abductors ; circumference of upper arm and forearm ; and perceived shoulder disability in ADLs compared with the SLNB group . Multivariate linear regression analysis showed that ALND could predict a decrease of range of motion in forward flexion , abduction , strength of shoulder abductors , grip strength , and shoulder-related ADLs and an increase in the circumference of the upper arm . Radiation of the axilla ( 19 patients ) predicts an additional decrease in shoulder range of motion . Conclusions : One year after treatment of breast cancer , there is significantly less upper limb morbidity after SLNB compared with ALND . ALND is a predictor for upper limb morbidity The aim of this study was to analyse the accuracy of scintigraphic and gamma probe sentinel node ( SN ) localization in breast cancer patients who have been su bmi tted to neoadjuvant chemotherapy ( NC ) . Seventy-six patients with single breast cancer were included in the study , and were classified into two groups . Group 1 consisted of 40 women who had received NC  , and Group 2 consisted of 36 women who did not receive NC .  All patients received 111 MBq ( 3 mCi ) of 99Tcm-nanocolloid in 3 ml , by peritumoural injection . Anterior and lateral thoracic scans were obtained 2 h post-injection . The following day ( 18 - 24 h post-injection ) the patients underwent surgery and sentinel nodes were localized by using a gamma probe . Complete axillary lymph node dissection was performed in all patients . Histological analysis included haematoxylin-eosin in all cases and immunohistochemistry in 10 cases . In Group 1 , SNs were localized in 36/40 patients , histological analysis was performed in 34 and there were four false negatives ( 22 % ) . In Group 2 , SNs were localized in 32/36 patients , histological analysis was performed in 29 and there were two false negatives ( 9 % ) . Predictive negative values were 78 % and 90 % in Groups 1 and 2 , respectively . In summary , sentinel node localization in breast cancer patients su bmi tted to previous neoadjuvant chemotherapy is less accurate than in patients who do not receive this therapy . The procedure is not sufficiently accurate to localize the sentinel node , thus it can not be recommended in these patients PURPOSE To develop a guideline for the use of sentinel node biopsy ( SNB ) in early stage breast cancer . METHODS An American Society of Clinical Oncology ( ASCO ) Expert Panel conducted a systematic review of the literature available through February 2004 on the use of SNB in early-stage breast cancer . The panel developed a guideline for clinicians and patients regarding the appropriate use of a sentinel lymph node identification and sampling procedure from hereon referred to as SNB . The guideline was review ed by selected experts in the field and the ASCO Health Services Committee and was approved by the ASCO Board of Directors . RESULTS The literature review identified one published prospect i ve r and omized controlled trial in which SNB was compared with axillary lymph node dissection ( ALND ) , four limited meta-analyses , and 69 published single-institution and multicenter trials in which the test performance of SNB was evaluated with respect to the results of ALND ( completion axillary dissection ) . There are currently no data on the effect of SLN biopsy on long-term survival of patients with breast cancer . However , a review of the available evidence demonstrates that , when performed by experienced clinicians , SNB appears to be a safe and acceptably accurate method for identifying early-stage breast cancer without involvement of the axillary lymph nodes . CONCLUSION SNB is an appropriate initial alternative to routine staging ALND for patients with early-stage breast cancer with clinical ly negative axillary nodes . Completion ALND remains st and ard treatment for patients with axillary metastases identified on SNB . Appropriately identified patients with negative results of SNB , when done under the direction of an experienced surgeon , need not have completion ALND . Isolated cancer cells detected by pathologic examination of the SLN with use of specialized techniques are currently of unknown clinical significance . Although such specialized techniques are often used , they are not a required part of SLN evaluation for breast cancer at this time . Data suggest that SNB is associated with less morbidity than ALND , but the comparative effects of these two approaches on tumor recurrence or patient survival are unknown Purpose : Sentinel node ( SN ) biopsy is a reliable method for improved staging of breast cancer , offering an alternative to routine axillary dissection . Perhaps preoperative chemotherapy could increase the rate of false‐negative SN because of induced lymphatic changes . The aim of the study was to evaluate the utility of lymphoscintigraphy and of h and ‐held probe detection in the SN approach after chemotherapy , correlating it with histologic analysis of the axilla . Methods : Eighty‐three patients ( mean age , 53 years ; TNM stage I ) were studied prospect ively . They were separated into two groups : group 1 ( G1 ) , 37 patients with preoperative chemotherapy  and group 2 ( G2 ) , 46 patients without chemotherapy . Mean tumor size was 2 cm in both groups . Lymphoscintigraphy was performed 3 to 4 hours after peritumoral injection of Tc‐99 m dextran‐70 in a 0.2‐ml volume and activity of 14.8 MBq ( 0.4 mCi ) , performed under ultrasound or mammographic control . On the following day , each patient underwent tumor resection with axillary dissection , included the SN . Results : The SN was detected by scintigraphy in 78 patients ( 94 % ) . The failure of SN to predict the axillary histologic status was significantly higher ( P = 0.01 ) in G1 than in G2 ( 7 and 1 false‐negative result , respectively ) . Conclusion : Preoperative chemotherapy seems to impair axillary evaluation by SN biopsy and should be used cautiously in this subset of patients Objective : The aim of this multicenter r and omized trial was to assess the efficacy and safety of sentinel lymph node ( SLN ) biopsy compared with axillary lymph node dissection ( ALND ) . Background : All studies on SLN biopsy in breast cancer report a variable false negative rate , whose prognostic consequences are still unclear . Methods : From May 
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The reported SN success rates were heterogeneous and several variables were reported to be associated with decreased SN accuracy , i.e. initially positive clinical nodal status .
There is a potential role for SN biopsy following NAC which could be considered on an individual basis .
However , there is insufficient evidence to recommend this as a st and ard procedure .