Im my experience ER positivity varies greatly with fixation time to
such an extent that core biopsies ,fixed for a couple of hours, can
not be used to control breast lumps.
So make sure the tissue blocks are the same size and fixed for the
same length of time.
Also, use three grades of positivity in the control tissue, weak
moderate and high.  This ensures that the pathologist can esimate how
well the particular immuno run has worked.
As for the relationship between ER and PR positivity I am not
qualified to comment upon it.

Best Wishes
Steve Machin UK

 --- NAVEEDA FAHEEM KHAN  wrote: > HI
Histonetters
> any one in the histaland can solve my problem. we use DAKO ER/PR
> system for estrogen progestrone receptors in the patients mostly
> breast specimens. our specimens are fixed in 10% bufferred
> formalin. the problem is that our control show good positive
> results but test results are variable. our pathologist says that in
> most of the cases if Er is negative then PR should also negative
> this is rare phenomena that pr is positive and er negative if any
> one can guide me that will be great that how i can convince my
> pathologist please give me some literature articles also if you
> have
> thanks in advance
> naveeda
> 
> 
> --
> Naveeda Arshad
> Pathology Department
> Aga Khan university Hospital
> Karachi
> Pakistan 
> --
>  

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