ACOSOG Z11 Trial


  1. Accrual: May 1999 - December 2004 (early)
  2.  NCI: “Slow accrual and low event rate”
  3.  Original goal = 1900    (B04 ~420 node + patients)
  4.  End Points: Overall & Disease Free Survival, Local-Regional Failure


Controversies About Z11

1. Study did not reach accrual goal

    1. True: Recurrence and death rates were too low

2. Study was underpowered (might miss true significance):

    1. (55% chance of finding P<0.05 non-inferiority if present)
    2. Power matters if a study result…

   is not statistically significant (p>0.05)

    1. Z11 demonstrated:
      1. statistically significant non-inferiority (p<0.01)
        1. <1% chance SLND is inferior to ALND) 
          1. Only a 55% chance this “fact” would be found



Axillary Dissection for positive sentinel nodes 

(1-2+ SLN’s with BCS)

Is declared dead by ACOSOG







Project details

Tags: Axillary Management

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