End of molecular pathology for pathologists?

[leu345]

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If there is no profession fee billing code for molecular tests, does that mean there will be no business for pathologists in molecular tests? Will all the molecular labs be run by PHDs?

I just feel frustrated, if pathologists gave up this growing field, pathology as a medical speciaty is dying, slowly, but dying.

 

[AZpath]

Yes

 

[Johnny Sunshine]

A few months ago, several people in my department were preoccupied with the changing face of the pathology job market, the emergence of new technologies, and fears that pathologists will be even more marginalized and slowly pushed out of relevance in the future.

One attending decided to cheer us up by giving a presentation on the wonderful world of the future of pathology analysis, and actually left us feeling a renewed sense of hope and even excitement over the new techniques in development that we would one day be using commonplace.

Naturally, this all focused and depended heavily on molecular. 🙁

 

[Enkidu]

If there is no profession fee billing code for molecular tests, does that mean there will be no business for pathologists in molecular tests? Will all the molecular labs be run by PHDs?

I just feel frustrated, if pathologists gave up this growing field, pathology as a medical speciaty is dying, slowly, but dying.

But do these tests actually require a physician to interpret them?

 

[sssamsss]

Stick a fork in us. We're done.
We are being algorithmized out of biz. Why pay a pathologist do decide what test to do when the EMR algorithm decides. The test isn't "on formulary" ? It just can't be ordered. Simple.

 

[pathstudent]

Yeah. Wasnt that suppos to be our future, helping to make sense of complex testing.

Well now that they are on the clfs, it means private insurers won't pay us anything for it since they have quit paying pccl. The only reimbursement will be whatever you are already getting from your hospital admin via the part a money.

 

[gbwillner]

But do these tests actually require a physician to interpret them?

depends on the test

 

[Enkidu]

depends on the test

But if a test requires pathologist-level training to interpret, then it will have to be reimbursed, right? It would be an issue of liability.

 

[LADoc00]

Molecular Pathology has been the biggest 'Emperor Has No Clothes' fictious narrative academic pathology has ever sold this profession.

All the while universities have been training people in MolPath, it is quite apparent in a few short years CMS plans to have NO role whatsoever for boarded Pathologists in the field.

I called this over a decade and half ago coming out of grad school.

 

[2121115]

Molecular Pathology has been the biggest 'Emperor Has No Clothes' fictious narrative academic pathology has ever sold this profession.

All the while universities have been training people in MolPath, it is quite apparent in a few short years CMS plans to have NO role whatsoever for boarded Pathologists in the field.

I called this over a decade and half ago coming out of grad school.

Yep, those molecular fellowships are basically a waste of time for real world pathologists. Just another ancillary test now, that we won't be involved with. About as good as doing a cytogenetics fellowship or immunohistochemistry fellowship.

 

[lipomas]

Molecular path has been moving towards a POC model for awhile. Things are getting more automated. There is some interpretation but it reaelly doesn't have to be a pathologist. It probably should have pathologist involvement to ward off ill-informed decision making though.

 

[thebouque]

Do you people think that at least 1-2 months of molecular path should be required during residency?

 

[gbwillner]

The notion that Mol Path is dead for pathologists because of the way the new codes have been set up (temporarily, BTW) is preposterous. In fact, molecular path labs NEVER required that the director was trained as as molecular pathologist or even a pathologist at all. PhDs with ABMG certification are currently considered qualified for these positions, and have been for some time, so that's nothing new.

The point is that many of these tests will be critical in the future. Don't believe it? fine, that's your prerogative. But its the direction of all of medicine, and there are already molecular tests out there that change the course of therapy. There is no indication to think that the number of relevant tests will not increase. Most think this will happen at an ever-increasing rate.

Now, as pathologists, we can sit idly by and watch PhDs and ABMG-certified people from other fields (primarily Oncology and Peds) take the relevant tests from us, or we can own it now and develop it ourselves. This is a new opportunity that we have been given and we are in position to lead. We have all the samples, be they paraffin-embedded blocks or frozen tissue, and can use our leverage to develop relevant tests that will A: help render more accurate diagnoses and B: alter the course of therapy. We already act as consultants for physicians, and now have a new avenue to aid that consultation.

I see this no differently than how Rads took the initiative on diagnostic procedures, and we never did. Who questions their ability to do US guided Bx's now?

 

[Enkidu]

The notion that Mol Path is dead for pathologists because of the way the new codes have been set up (temporarily, BTW) is preposterous. In fact, molecular path labs NEVER required that the director was trained as as molecular pathologist or even a pathologist at all. PhDs with ABMG certification are currently considered qualified for these positions, and have been for some time, so that's nothing new.

The point is that many of these tests will be critical in the future. Don't believe it? fine, that's your prerogative. But its the direction of all of medicine, and there are already molecular tests out there that change the course of therapy. There is no indication to think that the number of relevant tests will not increase. Most think this will happen at an ever-increasing rate.

Now, as pathologists, we can sit idly by and watch PhDs and ABMG-certified people from other fields (primarily Oncology and Peds) take the relevant tests from us, or we can own it now and develop it ourselves. This is a new opportunity that we have been given and we are in position to lead. We have all the samples, be they paraffin-embedded blocks or frozen tissue, and can use our leverage to develop relevant tests that will A: help render more accurate diagnoses and B: alter the course of therapy. We already act as consultants for physicians, and now have a new avenue to aid that consultation.

I see this no differently than how Rads took the initiative on diagnostic procedures, and we never did. Who questions their ability to do US guided Bx's now?

But if pathology takes the lead on developing molecular assays that ultimately don't require pathologist interpretation, how will that be a benefit?

 

[Substance]

But if pathology takes the lead on developing molecular assays that ultimately don't require pathologist interpretation, how will that be a benefit?

Pathology as a field is a mess. It can't even define itself - what does "pathology" even mean? It's as nondescript as "family medicine".

Here's what will happen in the next 20 years: the advent of in-vivo molecular imaging will obviate the need for most if not all screening tests that require tissue. Defining resected cancers will be done not through the then outdated practice of microscopy but through genetic analysis. The results of these genetic analyses will be readable by the ordering physician, much like a CBC or BUN. Advancement in optical coherence tomography (OCT) will reduce the need to biopsy luminal or skin lesions, and though pathologists are the masters of microscopic analysis, the clinical services will own OCT. Blood,chem and micro isn't really medicine since PhDs can do it independently without physician oversight, so that's gone(it already is, really). That leaves the glorious important gore-ritual autopsies, and if virtual autopsies ever become billable, you'll lose those too.

I sense impending obsolescence for your field. The worst part is it could be avoided if your leadership had any sense to them. You are going to end up like nuclear medicine. No wonder students are avoiding pathology.

 

[leu345]

Let's hope physicians are not smart enough to read genetic analysis, that is only way "molecular pathology" will survive.

Pathology as a field is a mess. It can't even define itself - what does "pathology" even mean? It's as nondescript as "family medicine".

Here's what will happen in the next 20 years: the advent of in-vivo molecular imaging will obviate the need for most if not all screening tests that require tissue. Defining resected cancers will be done not through the then outdated practice of microscopy but through genetic analysis. The results of these genetic analyses will be readable by the ordering physician, much like a CBC or BUN. Advancement in optical coherence tomography (OCT) will reduce the need to biopsy luminal or skin lesions, and though pathologists are the masters of microscopic analysis, the clinical services will own OCT. Blood,chem and micro isn't really medicine since PhDs can do it independently without physician oversight, so that's gone(it already is, really). That leaves the glorious important gore-ritual autopsies, and if virtual autopsies ever become billable, you'll lose those too.

I sense impending obsolescence for your field. The worst part is it could be avoided if your leadership had any sense to them. You are going to end up like nuclear medicine. No wonder students are avoiding pathology.

 

[Enkidu]

Pathology as a field is a mess. It can't even define itself - what does "pathology" even mean? It's as nondescript as "family medicine".

Here's what will happen in the next 20 years: the advent of in-vivo molecular imaging will obviate the need for most if not all screening tests that require tissue. Defining resected cancers will be done not through the then outdated practice of microscopy but through genetic analysis. The results of these genetic analyses will be readable by the ordering physician, much like a CBC or BUN. Advancement in optical coherence tomography (OCT) will reduce the need to biopsy luminal or skin lesions, and though pathologists are the masters of microscopic analysis, the clinical services will own OCT. Blood,chem and micro isn't really medicine since PhDs can do it independently without physician oversight, so that's gone(it already is, really). That leaves the glorious important gore-ritual autopsies, and if virtual autopsies ever become billable, you'll lose those too.

I sense impending obsolescence for your field. The worst part is it could be avoided if your leadership had any sense to them. You are going to end up like nuclear medicine. No wonder students are avoiding pathology.

Perhaps, though I doubt that tumors can be clearly distinguished by simple molecular tests by a clinician.

IHC should be superior to molecular tests to diagnose tumors, since IHC looks at actual expression as opposed to just the DNA. Am I right in thinking that no cancer can be diagnosed by IHC alone without morphology? If that's the case, then no molecular test can do it either. But I'm sure that molecular tests, when ordered appropriately, will be able to help further distinguish different prognoses and treatment strategies.

 

[malchik]

Pathology as a field is a mess. It can't even define itself - what does "pathology" even mean? It's as nondescript as "family medicine".

Here's what will happen in the next 20 years: the advent of in-vivo molecular imaging will obviate the need for most if not all screening tests that require tissue. Defining resected cancers will be done not through the then outdated practice of microscopy but through genetic analysis. The results of these genetic analyses will be readable by the ordering physician, much like a CBC or BUN. Advancement in optical coherence tomography (OCT) will reduce the need to biopsy luminal or skin lesions, and though pathologists are the masters of microscopic analysis, the clinical services will own OCT. Blood,chem and micro isn't really medicine since PhDs can do it independently without physician oversight, so that's gone(it already is, really). That leaves the glorious important gore-ritual autopsies, and if virtual autopsies ever become billable, you'll lose those too.

I sense impending obsolescence for your field. The worst part is it could be avoided if your leadership had any sense to them. You are going to end up like nuclear medicine. No wonder students are avoiding pathology.

Wait, you're an attending now?
You have a very superficial view of pathology. First, contemporary pathology can be pretty well defined as diagnostic medicine. Second, there are huge obstacles in molecular tests superseding histology, such as genetic heterogeneity, non-genetic phenomena (ie, epigenetics) that affect tumor phenotype, and cost. Enkidu correctly points out that it is expression and phenotype that really matters, ie the proteome. Proteomics, genomics, and epigenomics have a long way to go before they can beat the two seconds it takes a pathologist to look at a bladder biopsy and get reimbursed the whopping 88305.

 

[Substance]

Wait, you're an attending now?
You have a very superficial view of pathology. First, contemporary pathology can be pretty well defined as diagnostic medicine. Second, there are huge obstacles in molecular tests superseding histology, such as genetic heterogeneity, non-genetic phenomena (ie, epigenetics) that affect tumor phenotype, and cost. Enkidu correctly points out that it is expression and phenotype that really matters, ie the proteome. Proteomics, genomics, and epigenomics have a long way to go before they can beat the two seconds it takes a pathologist to look at a bladder biopsy and get reimbursed the whopping 88305.

Who's to say that genetics isn't good enough to begin with? Sure if there are aberrant results one could consult other methods like the microscope, but I would wager that such aberrant situations would be far too few to warrant the absolute number of pathologists being trained or practicing.

OCT and in vivo molecular imaging methods are closer to being used than full-spectrum proteomics/genetics. This is a turf war that I would wager your field will lose. In fact, I doubt your society will make any effort to take ownership of those technologies.

Though contemporary pathology could be considered diagnostic medicine, so could radiology. The diagnoses are different in both cases; radiology makes anatomical diagnoses, pathology makes microscopic/cellular ones. But if you ask any clinician/politician/civilian, pathology is where the lab is and they do lab tests where you put tissue or fluids in a black box and an answer comes out. It's not really reflective of the reality of what you do, but you can't blame them for thinking that. Your field's representatives do a very poor job in defining your role in medical care.

 

[Enkidu]

Who's to say that genetics isn't good enough to begin with? Sure if there are aberrant results one could consult other methods like the microscope, but I would wager that such aberrant situations would be far too few to warrant the absolute number of pathologists being trained or practicing.

OCT and in vivo molecular imaging methods are closer to being used than full-spectrum proteomics/genetics. This is a turf war that I would wager your field will lose. In fact, I doubt your society will make any effort to take ownership of those technologies.

Though contemporary pathology could be considered diagnostic medicine, so could radiology. The diagnoses are different in both cases; radiology makes anatomical diagnoses, pathology makes microscopic/cellular ones. But if you ask any clinician/politician/civilian, pathology is where the lab is and they do lab tests where you put tissue or fluids in a black box and an answer comes out. It's not really reflective of the reality of what you do, but you can't blame them for thinking that. Your field's representatives do a very poor job in defining your role in medical care.

I do not think that molecular imaging will play a significant role in diagnosis. It should be about as diagnostic for a cancer as the result of a single IHC stain in the absence of morphology. Maybe it will be important for staging, but I doubt that it will play more than a marginal role in diagnosis apart from in areas inaccessible to biopsy.

As for genetics... Honestly it's obvious that they're not good enough. If IHC alone isn't good enough then how could molecular be? Unless we're talking about whole genome arrays or something - which will obviously require an expert to interpret.

 

[malchik]

Who's to say that genetics isn't good enough to begin with? Sure if there are aberrant results one could consult other methods like the microscope, but I would wager that such aberrant situations would be far too few to warrant the absolute number of pathologists being trained or practicing.

OCT and in vivo molecular imaging methods are closer to being used than full-spectrum proteomics/genetics. This is a turf war that I would wager your field will lose. In fact, I doubt your society will make any effort to take ownership of those technologies.

Though contemporary pathology could be considered diagnostic medicine, so could radiology. The diagnoses are different in both cases; radiology makes anatomical diagnoses, pathology makes microscopic/cellular ones. But if you ask any clinician/politician/civilian, pathology is where the lab is and they do lab tests where you put tissue or fluids in a black box and an answer comes out. It's not really reflective of the reality of what you do, but you can't blame them for thinking that. Your field's representatives do a very poor job in defining your role in medical care.

You don't seem to understand. Aberrant results are not the issue. The issue I was raising, and it is only one of many issues, is that individual cells within a tumor have different genetics. Molecular studies on tumors all begin with a pathologist looking at a slide and identifying which cells to dissect and sequence.

 

[WEBB PINKERTON]

With all the taxes in the Affordable Care act for medical device companies, look for innovation to slow down considerably.

 

[2121115]

There was never a beginning for molecular pathology for pathologists, so this isn't the end.

 

[KCShaw]

A test doesn't necessarily need a billable 'interpretation' in order for the lab to be best run by a pathologist, nor for that pathologist to make a living off of it. Sure, it would be nice to be absolutely required, but we can't exactly just hold our breath and hope.

As for replacing grandpappy histology, pretty much the same arguments came up when electron microscopy splashed on the scene, and then IHC, and mol-gen has been talked about in that light to some extent since we learned what DNA is. The field will change, yes, as it already has, but I've seen nothing which is clearly destined to be such a game changer as to make the grunt at the microscope completely obsolete.

 

[mrp]

Histology is cheap, easy, fast, generally accurate, and yields a huge amount of information. It's not going anywhere anytime soon.

 

[LADoc00]

There was never a beginning for molecular pathology for pathologists, so this isn't the end.

Well..there was an ILLUSION of a beginning when misguided academics began creating an actual fellowship training program for molpath...but yes, it was an abortion albiet a late term one which now is requiring some power tools and mad suction to kill off the remaining pathologists stubbornly clinging to life here.

 

[medfield12]

Well..there was an ILLUSION of a beginning when misguided academics began creating an actual fellowship training program for molpath...but yes, it was an abortion albiet a late term one which now is requiring some power tools and mad suction to kill off the remaining pathologists stubbornly clinging to life here.

LADoc00,
Thanks for all your excellent posts on this site. Please continue.

 

[leu345]

Without CP lab including molecular diagnostics, pathologists should be re-defined as "morphologists". It is a great skill and take years to refine and improve, but it is just a bit sad to see that pathologist=morphologist. If pathology is not evolving with science and technology, it will die slowly. The exact reason for that is that pathology was and is the bridge for science and medicine to meet.

I can see and understand the resistance to new technology from the tranditional pathologists, but whether you like it or not, it is here already. The market for molecular diagnostics will triple in next 5 years. Our leadship really should have the vision and we pathologists should take the lead in this field.

Well..there was an ILLUSION of a beginning when misguided academics began creating an actual fellowship training program for molpath...but yes, it was an abortion albiet a late term one which now is requiring some power tools and mad suction to kill off the remaining pathologists stubbornly clinging to life here.

 

[KeratinPearls]

Without CP lab including molecular diagnostics, pathologists should be re-defined as "morphologists". It is a great skill and take years to refine and improve, but it is just a bit sad to see that pathologist=morphologist. If pathology is not evolving with science and technology, it will die slowly. The exact reason for that is that pathology was and is the bridge for science and medicine to meet.

I can see and understand the resistance to new technology from the tranditional pathologists, but whether you like it or not, it is here already. The market for molecular diagnostics will triple in next 5 years. Our leadship really should have the vision and we pathologists should take the lead in this field.

So what is the new thing in molecular diagnostics? In vivo endoscopy? Please educate me as I don't know what is hot right now. How sensitive is it in making a diagnosis? Can you make a diagnosis of INVASIVE ADENOCARCINOMA via molecular diagnostics?

Are you an attending, resident or fellow?

I think Path will still continue with H&E until the day I retire in the next 30 years or so.

 

[WEBB PINKERTON]

So what is the new thing in molecular diagnostics? In vivo endoscopy? Please educate me as I don't know what is hot right now. How sensitive is it in making a diagnosis? Can you make a diagnosis of INVASIVE ADENOCARCINOMA via molecular diagnostics?

Are you an attending, resident or fellow?

I think Path will still continue with H&E until the day I retire in the next 30 years or so.

The Affordable health care act is gonna plunge us into a dark age. Innovation is gonna grind to halt it looks like. Obama saved H+E.

 

[leu345]

OK, let's talk about INVASIVE ADENOCARCINOMA, which is a morphologic diagnosis. It is already happening that clinicians are be happy with that diagnosis, how should this tumor be treated? Does it have EGFR mutation? Does it have HER2 mutation? What is the prognosis? Is this part of familiar syndrome?........You see, invasive adenocarcinoma itself as a diagnosis is not enough. More so in future.

I agree HE slides will not be replaced in our lfe time, but if we are not embracing the new technology, give up the growing field to PhDs. Future pathologists will suffer.

So what is the new thing in molecular diagnostics? In vivo endoscopy? Please educate me as I don't know what is hot right now. How sensitive is it in making a diagnosis? Can you make a diagnosis of INVASIVE ADENOCARCINOMA via molecular diagnostics?

Are you an attending, resident or fellow?

I think Path will still continue with H&E until the day I retire in the next 30 years or so.

 

[Enkidu]

The Affordable health care act is gonna plunge us into a dark age. Innovation is gonna grind to halt it looks like. Obama saved H+E.

What does the ACA have to do with medical research?

 

[Enkidu]

OK, let's talk about INVASIVE ADENOCARCINOMA, which is a morphologic diagnosis. It is already happening that clinicians are be happy with that diagnosis, how should this tumor be treated? Does it have EGFR mutation? Does it have HER2 mutation? What is the prognosis? Is this part of familiar syndrome?........You see, invasive adenocarcinoma itself as a diagnosis is not enough. More so in future.

I agree HE slides will not be replaced in our lfe time, but if we are not embracing the new technology, give up the growing field to PhDs. Future pathologists will suffer.

Molecular tests provide valuable information that will play an increasing role in pathology reports, but it is ultimately a kind of ancillary test, isn't it? I don't see how H&E can ever be replaced any more than physical exams could be replaced in clinical medicine. I mean... how can you produce a differential diagnosis without examining the patient/tissue?

Also, in what way could other fields take molecular diagnostics? In order to order molecular tests, you first need tissue, right? And not only tissue, but you need to already have a differential diagnosis to know which molecular tests to order... So how would this work? The clinician notices a mass on radiology, gets it biopsied and orders a panel of molecular tests on without anyone even looking at it? Isn't that the equivalent of giving a patient a CT without getting a physical exam?

 

[Substance]

Molecular tests provide valuable information that will play an increasing role in pathology reports, but it is ultimately a kind of ancillary test, isn't it? I don't see how H&E can ever be replaced any more than physical exams could be replaced in clinical medicine. I mean... how can you produce a differential diagnosis without examining the patient/tissue?

Also, in what way could other fields take molecular diagnostics? In order to order molecular tests, you first need tissue, right? And not only tissue, but you need to already have a differential diagnosis to know which molecular tests to order... So how would this work? The clinician notices a mass on radiology, gets it biopsied and orders a panel of molecular tests on without anyone even looking at it? Isn't that the equivalent of giving a patient a CT without getting a physical exam?

Patients get imaging without physical examination all of the time. In fact, it seems to be a trend in some ERs. Nonetheless, it provides excellent information that is generally superior to a physical exam in many if not most respects.

As for how it will work, the doctor who obtains the tissue will send it off to Johnny PhD for "molecular tests" which will probably include some sort of microarray. It does not take an expert to read a microarray, just a very good computer program. The PhD will do the lab mixings and the computer will spit out the result.

As for "invasive adenocarcinoma" or any other diagnosis, its behavior is determined by its genetics. Once the genetic expression profiles for invasion, angiogenesis, etc have been determined, and that day is coming sooner than you think, there will be absolutely no need to look down a microscope at it. The "molecular tests" will tell you all that is required.

The only hope your field has is OCT and interventional stuff, and your weak field is never going to take the lead on that. The day pathologists are doing scopes and OCT is the day I shave my head and become a Buddhist monk.

But that's ok, you should probably concentrate on preventing radiologists from billing for virtual autopsies. Otherwise there will be absolutely nothing left for pathologists to do.

 

[leu345]

That is a very good analogue. Now, how about someone tell you that, let's focus on physical exam, leave CT to others. We have been doing physical exams for decade and it works well.

That is what is happening now in pathology. CT is here, but we don't want to own it. We only want to do physical exam.

 

[Enkidu]

Patients get imaging without physical examination all of the time. In fact, it seems to be a trend in some ERs. Nonetheless, it provides excellent information that is generally superior to a physical exam in many if not most respects.

As for how it will work, the doctor who obtains the tissue will send it off to Johnny PhD for "molecular tests" which will probably include some sort of microarray. It does not take an expert to read a microarray, just a very good computer program. The PhD will do the lab mixings and the computer will spit out the result.

As for "invasive adenocarcinoma" or any other diagnosis, its behavior is determined by its genetics. Once the genetic expression profiles for invasion, angiogenesis, etc have been determined, and that day is coming sooner than you think, there will be absolutely no need to look down a microscope at it. The "molecular tests" will tell you all that is required.

The only hope your field has is OCT and interventional stuff, and your weak field is never going to take the lead on that. The day pathologists are doing scopes and OCT is the day I shave my head and become a Buddhist monk.

But that's ok, you should probably concentrate on preventing radiologists from billing for virtual autopsies. Otherwise there will be absolutely nothing left for pathologists to do.

Well... Doing CT before a physical exam results in unnecessary testing and wasted resources, not to mention the harm of radiation exposure. Why order molecular tests for a disease that could be ruled out by simply looking at the cells? That's bad medicine, for one, since the predictive value of a test depends on its pre-test probability.

As for your ideas about genetics... They're naive. Behavior of a cell is determined by expression, not genetics. That should be obvious, since all somatic cells have the same DNA but express different proteins. DNA can't distinguish an epithelial cell from a hepatocyte from a neutrophil. Tumor behavior is also determined by cell type and protein expression. Molecular studies can provide further information about a tumor, but not superior information.

 

[Enkidu]

That is a very good analogue. Now, how about someone tell you that, let's focus on physical exam, leave CT to others. We have been doing physical exams for decade and it works well.

That is what is happening now in pathology. CT is here, but we don't want to own it. We only want to do physical exam.

Is this directed at me? I think that ordering appropriate molecular tests after doing normal morphology and IHC is a good idea and will be a growing part of pathology. Is there resistance to this? My only suggestion was that its naive to think molecular tests can do everything. What exactly is it that you envision?

 

[scienceguy19]

Well we can now detect different protein expression even though DNA is same or similar. That's molecular proteomics. So maybe that might provide superior information than knowing that a cell has a large N/C ratio and is hyperchromatic.

Well... Doing CT before a physical exam results in unnecessary testing and wasted resources, not to mention the harm of radiation exposure. Why order molecular tests for a disease that could be ruled out by simply looking at the cells? That's bad medicine, for one, since the predictive value of a test depends on its pre-test probability.

As for your ideas about genetics... They're naive. Behavior of a cell is determined by expression, not genetics. That should be obvious, since all somatic cells have the same DNA but express different proteins. DNA can't distinguish an epithelial cell from a hepatocyte from a neutrophil. Tumor behavior is also determined by cell type and protein expression. Molecular studies can provide further information about a tumor, but not superior information.

 

[Enkidu]

Well we can now detect different protein expression even though DNA is same or similar. That's molecular proteomics. So maybe that might provide superior information than knowing that a cell has a large N/C ratio and is hyperchromatic.

Well, IHC is already detecting protein expression as well as providing the morphological information that you mentioned, but I'm sure that proteomics will play a role too. Once again, though, why do a proteomic test completely in the dark without bothering to look at the tissue? The "tumor" may be a granuloma, might as well take a look before we blow thousands of dollars on proteomics.

 

[malchik]

Well... Doing CT before a physical exam results in unnecessary testing and wasted resources, not to mention the harm of radiation exposure. Why order molecular tests for a disease that could be ruled out by simply looking at the cells? That's bad medicine, for one, since the predictive value of a test depends on its pre-test probability.

As for your ideas about genetics... They're naive. Behavior of a cell is determined by expression, not genetics. That should be obvious, since all somatic cells have the same DNA but express different proteins. DNA can't distinguish an epithelial cell from a hepatocyte from a neutrophil. Tumor behavior is also determined by cell type and protein expression. Molecular studies can provide further information about a tumor, but not superior information.

"Naive" is a good description for Substance's views expressed above. I already tried to explain that if a surgeon submitted a chunk of tissue that was put on "some kind of microarray" you would get back thousands of different expression profiles and hundreds of genomic sequences, depending on how genetically unstable the tumor is. "Profiles for invasion and angiogenesis" and "sooner than you think"? A lot longer than you think, actually. Example: Epithelial mesenchymal transition has been around as a developmental concept for about a hundred years and as a tumor progression paradigm for decades, and people still don't even agree that it exists.

To bypass morphology, a molecular test is going to have to distinguish benign vs. malignant, invasive vs. not, tissue of origin, differentiation, margin status(?), and do it for under 80 dollars of global and a day of turn-around time. A few hours if you're Mayo and you freeze everything. = Not happening for a long time.

 

[gbwillner]

As a molecular pathologist I can tell you the plan is not, and has never been, to replace H&E and bypass histopathology. Those who spout that either do not understand the science and technology, or are naive and fear a future where they could be replaced by a computer. Molecular path adds another layer to aid diagnoses and to help the clinicians pick a treatment regimen. Isn't that the basis of what a pathologist does?

Molecular path by its nature is infinitely more complex than IHC. We have gone from being able to look at mutations in one gene/test to all genes/test. If you don't think it takes an expert to tell you what that means you just don't understand what is going on. It's like saying why go to med school and residency to train to be a physician when any idiot could diagnose a cold by opening up Cecil's essentials of medicine.

 

[2121115]

CT is here, but we don't want to own it. We only want to do physical exam.

That is not even remotely a comparable situation.

 

[pathstudent]

Everytime I see this thread...

The REM song runs through my head "Watson. Crick. array based CGH. Kary Mullis PCR. It's the end of molecular pathology as we know it. It's the end of molecular pathology as we know it. It's the end of molecular pathology as we know it. And I feel fine."

You just have to say "molecular pathology" super fast.