[Histonet] Ventana Benchmark closed systems vs Open system stainers - a diatribe

Brian Chelack brian.chelack <@t> usask.ca
Sun May 28 15:55:17 CDT 2006


It is interesting to note how firmly people plant themselves on one side or
the other of the "Ventana Issues". I have worked with many different
immunostainers, going back to the old capillary gap Fisher Code-Ons. In my
estimation every company that makes a stainer has to make some sort of
compromise when it comes to its design. Every stainer has its own set of
strengths and weaknesses; I have yet to see one that is "perfect". As
technologists we all want to see the perfect machine that allows us to load
individual slides whenever we want, process them completely, error free and
automatically right down to the coverslip, and do it for next to nothing. As
an added feature the stainer should allow all the IHC technologists to
maintain the "aura" of being highly skilled irreplaceable technical artists
who can perform magic on paraffin sections. This means job security because
department supervisors are certain their labs require the technologists who
are busily tending to their "automated" machines. This "perfect" company
then must sell us one of these instruments and be prepared to walk away from
the marketplace, because we technologists don't want to be "beholdin" to
them for any further purchases. We are mercenaries who will abandon them in
an instant for the next company that offers us reagents for 3% cost savings.

So if I am this company what should I do? Why should I invest a great deal
of time and money into developing a stainer that provides me with no chance
for an ongoing revenue stream? 

I have seen companies with good technology (for their times), fade away due
to an inability to maintain a healthy cash flow. Patents are sold, other
companies try to adapt the technology to their product lines and life
staggers on. On the other hand, companies that keep their reagents
proprietary, and yes expensive, do have the money available to develop their
product lines and look at new ideas. I think companies like Ventana, do
charge a lot of money for their reagents, but I also see how companies like
Dako, with their new Artisan stainer is slowly moving towards generating
ongoing revenue streams. Watch for the convergence!

Which one is the best choice?  Well it depends. Every lab requires at least
one person to turn on the lights and make coffee, so this person is also
available to perform IHC staining. Typically an IHC lab begins with someone
doing the IHC staining by hand. If this person is at least moderately
skilled the lab becomes successful and requests for stains start arriving,
and arriving and arriving.  Another skilled technologist is hired to no
avail, before long, both are swamped and begging for more help, but budgets
are always tight so it must be time for an automated IHC stainer. What
should we choose? 

Well the ability to stain large numbers of slides is important, right? So we
look at models that offer the ability to stain many slides at once, but
these models can only output their slides once or twice per day. This means
you need to keep your two skilled technologists around in order to manage
the large bulges of work expelled by the stainers periodically throughout
the day. 

Is speed important? Well of course it is, but turn around times are
inversely proportional to the capacity of the equipment. Think about what
happens to the slide that arrives at the stainer 10 minutes after you hit
the start button, for that that matter, think about what happens to the
first slide that arrives at the stainer and then waits until enough other
slides are present to warrant starting the equipment. It is becoming
apparent that single piece flow is the most efficient method for improving
turn around times, but to my knowledge, all the equipment makers (Ventana
included, see the new BenchMark XT), believe that more slides in a batch is
better. Histo techs cut one block at a time and Pathologists look at one
slide at a time, but for some reason we like to batch and queue large
numbers of slides in the IHC lab.

Is quality important? Obviously it is.  So why do we need to have highly
skilled technologists overseeing the "automated" equipment? Lets be honest
about our "automated" equipment, what we really have are glorified automated
pipetting devices. Some of them provide the reagents, some we have to make
up the reagents ourselves, some heat the slide some do not. 

IHC is not automated! 

If it were, the histotech cutting the section could place a bar-coded slide
into a slot in the stainer as it was cut and the stainer would run the
entire process, spitting out the completed slide onto the pathologists
microscope where he/she would examine it. Slides would be delivered to the
pathologist in a steady stream of 1 every couple of minutes, the process
would be faster and the entire IHC lab would be eliminated. Oh wait, that
would mean I would be out of work................... never mind (with
apologies to SNL).

Seriously though, the two largest cost drivers in IHC labs are the staff and
the equipment/reagents. The people who have evolved in the labs generally
like to tinker with their stains, "I can tweak it a bit to make it do this
or that". In a perfect world, lab managers would pay big money for a machine
that was, as described above, "truly automated".  Technologists actually
don't like not being able to tinker with a stain, add to that the costs for
the reagents that are so much higher than our home made ones and it's no
wonder we resist these pieces of equipment. They are not truly automated and
they limit the technologists ability to prove their value in the lab. As an
aside have you ever considered the markup on some of the polyclonal rabbit
antibodies for human diagnostics. I have seen 100 uL of rabbit serum sell
for hundreds of dollars, do your lab techs complain about these prices?

Now, I realize that a true research lab operates under a different set of
parameters and probably does require someone who can tweak a stain. These
research labs are generally not high volume labs though, and realistically
many could probably operate manually. It's the high volume labs that run
20-30 or more of the same stain every day that really need automation.

What I hope will happen, is that two or more companies will embrace the
ongoing revenue stream model currently used by Ventana, and then we should
see a rapid evolution towards truly automated IHC stainers. Competition is
always brings out the best in industry. Look at how clinical chemistry
analyzers now are able to process serum samples, with little need for the
technologist to fuss with the process.  That should be the goal of the IHC
stainer manufacturer. 

So what type of stainer should you choose? Well if you already have a good
technologist or two in the lab and you have no opportunity reduce your
personnel costs and if money is tight, you will likely choose an open
system. My experience has been that open systems will lead to somewhat more
variability in the results obtained, sometimes this can be good and
sometimes it is bad. I have also seen that companies lose interest in
product lines that no longer have a high profit potential, so beware of
obsolescence. If high throughput and quick turn around time is critical,
then I would recommend multiple units of the smallest volume stainer you can
get (for more on this read up on LEAN thinking). If accessing or retaining
highly skilled people are not in your future then you should be moving
towards the "most automated" equipment like the Ventana machines. If you are
a research lab with skilled people already in place then resist the move to
automated equipment for as long as possible. There's just no sense in having
the highest costs of both worlds.

As Joe Nocito said earlier this week:

Let the flaming begin....


Brian Chelack
Prairie Diagnostic Services
2604-52 Campus Drive
Saskatoon SK
S7N 5B4
306-966-7241





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