***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: PURPOSE This study sought to estimate cardiac dysfunction ( CD ) risk for patients receiving trastuzumab ;  to characterize observed CD by severity , treatment , and clinical outcome ; to assess effects of baseline clinical risk factors on CD ; and to assess effects of cumulative doses of anthracyclines and trastuzumab on CD . PATIENTS AND METHODS A retrospective review of records for patients enrolled onto any of seven phase II and III trastuzumab clinical trials was performed . Predefined criteria were used for the diagnosis , and the New York Heart Association functional classification system was used to document CD severity . Product-limit estimates were used to summarize the cumulative anthracycline and trastuzumab doses at the time of CD onset . RESULTS Patients treated with trastuzumab  were found to be at an increased risk for CD . The incidence was greatest in patients receiving concomitant  trastuzumab and anthracycline plus cyclophosphamide ( 27 % ) . The risk was substantially lower in patients receiving paclitaxel and trastuzumab ( 13 % ) or trastuzumab alone ( 3 % to 7 % ) ; however , most of these patients had received prior anthracycline therapy . CD was noted in 8 % of patients receiving anthracycline plus cyclophosphamide and 1 % receiving paclitaxel alone . Most trastuzumab-treated patients developing CD were symptomatic ( 75 % ) , and most improved with st and ard treatment for congestive heart failure ( 79 % ) . CONCLUSION Trastuzumab is associated with an increased risk of CD , which is greatest in patients receiving concurrent anthracyclines . In most patients with metastatic breast cancer , the risk of CD can be justified given the improvement in overall survival previously reported with trastuzumab Background A r and omized Phase II study evaluated the activity of weekly paclitaxel versus its combination with trastuzumab for treatment of patients with advanced breast cancer overexpressing HER-2 . Patients and methods Among 124 patients r and omized , 123 are assessable for toxicity and 118 for response . Patients received weekly paclitaxel single agent ( 80 mg/m2 ) or combined with trastuzumab ( 4 mg/kg loading dose , then weekly 2 mg/kg ) . HER-2 overexpression was determined by immunohistochemistry ( IHC ) . Patients with 2+/3 + IHC scores were eligible . IHC was compared with HER-2 serum extracellular domain ( ECD ) . Results Patient characteristics were similar in the two arms . Both treatments were feasible and well tolerated with no grade 4 hematologic toxicity . No patient developed cardiac toxicity . The combined treatment was statistically significant superior for overall response rate ( ORR ) ( 75 % vs. 56.9 % ; P = 0.037 ) , particularly in the subset of IHC 3 + patients ( 84.5 % vs. 47.5 % ; P = 0.00050 ) . A statistically significant better median time to progression was seen in the subgroup with IHC 3 + ( 369 vs. 272 days ; P = 0.030 ) and visceral disease ( 301 vs. 183 days ; P = 0.0080 ) treated with combination . Multivariable analysis of predictive factors showed that only IHC score retained statistically significant value for ORR ( P = 0.0035 ) . Conclusion Weekly paclitaxel plus trastuzumab is highly active and safe and it is superior to paclitaxel alone in patients with IHC score of 3 + Long-term beta blockade for perhaps a year or so following discharge after an MI is now of proven value , and for many such patients mortality reductions of about 25 % can be achieved . No important differences are clearly apparent among the benefits of different beta blockers , although some are more convenient than others ( or have slightly fewer side effects ) , and it appears that those with appreciable intrinsic sympathomimetic activity may confer less benefit . If monitored , the side effects of long-term therapy are not a major problem , as when they occur they are easily reversible by changing the beta blocker or by discontinuation of treatment . By contrast , although very early IV short-term beta blockade can definitely limit infa rct size , more reliable information about the effects of such treatment on mortality will not be available until a large trial ( ISIS ) reports later this year , with data on some thous and s of patients entered within less than 4 hours of the onset of pain . Our aim has been not only to review the 65-odd r and omized beta blocker trials but also to demonstrate that when many r and omized trials have all applied one general approach to treatment , it is often not appropriate to base inference on individual trial results . Although there will usually be important differences from one trial to another ( in eligibility , treatment , end-point assessment , and so on ) , physicians who wish to decide whether to adopt a particular treatment policy should try to make their decision in the light of an overview of all these related r and omized trials and not just a few particular trial results . Although most trials are too small to be individually reliable , this defect of size may be rectified by an overview of many trials , as long as appropriate statistical methods are used . Fortunately , robust statistical methods exist -- based on direct , unweighted summation of one O-E value from each trial -- that are simple for physicians to use and underst and yet provide full statistical sensitivity . These methods allow combination of information from different trials while avoiding the unjustified direct comparison of patients in one trial with patients in another . ( Moreover , they can be extended of such data that there is no real need for the introduction of any more complex statistical methods that might be more difficult for physicians to trust . ) Their robustness , sensitivity , and avoidance of unnecessary complexity make these particular methods an important tool in trial overviews 
    Output:
    
CONCLUSIONS Our study supports the addition of trastuzumab to chemotherapy which is effective and tolerated for metastatic breast cancer with HER2 + patients .
Of note , more adverse events will occur followed the use of trastuzumab , especially cardiac toxicity , with two treatment regimens