IHC Diagnostic Tool for Prostate Cancer

[cesanon]

Tall_Allen recently mentioned a prostate cancer diagnostic tool called an IHC : "The IHC should include as many of these as possible: AR (androgen receptor), PSA, PSMA, MSH2, MSH6, STEAP1, PD-L1, chromogranin A (CGA), neuron-specific enolase (NSE), synaptophysin (SYP), DLL-3, CD56, Somatostatin (SST).In your case, an FDG PET scan may show more than a PSMA PET." Tall_Allen

Has anyone ever had this?

Do you know what it is good for? What it is not good for? When to use it? When it is not useful.

What it does that other diagnostic tools don't?

Thanks

[Tall_Allen]

I have always recommended it as well as met histology and genomics for patients not responsive to systemic therapies. It's not mysterious.

[Ahk1 in reply to Tall_Allen]

Do you have a link to this tool please? Does it have a user interface? How to use it? Thanks

[Tall_Allen in reply to Ahk1]

It's just lab pathology tests ordered by your MO. Nothing new.

[Ahk1]

Do you have a link to this tool please? Does it have a user interface? How to use it? Thanks

[cesanon in reply to Ahk1]

It appears to be a lab test conducted on tissue samples.

[tango65]

This is what others recommend:

urotoday.com/conference-hig...

My understanding is that histological studies are the most important tool for the diagnosis of Neuroendocrine prostate cancer.

meridian.allenpress.com/apl...

[cesces in reply to tango65]

This looks like genetic testing?

[tango65 in reply to cesces]

Genetic, histological and IHC to detect Neuroendocrine PC, and mutations which could respond to PARP inhibitors or keytruda or similars.

One could study PSMA as well but the SUV values of the mets in a PSMA PET/CT are what will indicate possible good response to Lu 177 PSMA treatment.

Genetic studies and/or IHC studies can also have a prognostic value. Cancers with PTEN, RB1 and pt53 mutations are associated with bad prognosis.

What TA proposes is very comprehensive. I wish it would be done in most of the patients.

[KocoPr]

It is genetic testing. I had it don on my tumor it picked up TMPRSS2/ERG fusion and MSH6-Loss before sample got degraded. It was from my 5yr old prostatectomy so it was near end of life for genetic testing.

[Tall_Allen in reply to KocoPr]

No, it's not genomics.

[KocoPr in reply to Tall_Allen]

Really! Geez I have so much to learn!Thank you TA

[KocoPr]

ncbi.nlm.nih.gov/pmc/articl...

Immunohistochemistry (IHC) is an important application of monoclonal as well as polyclonal antibodies to determine the tissue distribution of an antigen of interest in health and disease. IHC is widely used for diagnosis of cancers; specific tumor antigens are expressed de novo or up-regulated in certain cancers. This article deals with the various applications of IHC in diagnosis of diseases, with IHC playing an important role in diagnostic and research laboratories.

[Hidden]

This is nothing new. If you are really interested on how Pathologists aid a Medical Oncologist, please read:

ncbi.nlm.nih.gov/pmc/articl...

GD

[KocoPr]

Interesting thanks.So even though it is used a a marker for PCa progression no medical practice can be used because these markers Ki-67, p53, ERG (i have), PTEN, and MYC have not been validated.

Here is the conclusion of the above linked 2018 study.

The only thing in my favor is the darolutamide i am taking interferes with the TMPRSS2/ERG fusion. Which by the way is the exact same pathway covid uses to enter cells.

Conclusion

In summary, there are several studies relating immunohistochemical markers with clinical-laboratory outcomes in prostate cancer, the most frequent being Ki-67, p53, ERG, PTEN, and MYC. However, none of these markers have been validated and, consequently, they cannot be applied in medical practice.

Positive staining for Ki-67, p53 and MYC were related to higher tumor grade and stage. Ki-67 was also related to PSA levels, disease-free interval and tumor-specific survival (the latter also being related to p53). For PTEN, its loss showed a higher association with biochemical recurrence and a worse prognosis, as well as Gleason score and tumor stage. Finally, ERG showed a strong association with biochemical recurrence.

If applied in specific situations, the use of these markers could guide the process of therapeutic decision making.

[cesces in reply to KocoPr]

"If applied in specific situations, the use of these markers could guide the process of therapeutic decision making."

Interesting

Putting aside the issue of validation, that these markers exist, do you know under what circumstances can they inform a treatment decision?

I have p53. That means apparently that I have a chromosome repair problem.

Even if it were validated, do you have any idea on how that might inform treatment decisions?

[KocoPr]

I have TMPRSS2/ERG fusion and MSH6-Loss and as far as my Oncologist knows that 50% of advanced PCa have this IHC marker in tumors but their is no specific trials or drugs that are made to target this.

Big thing here is thelutamides like darolutamide, Enzalutimide and apalutamide actually block this genes sction preventing cell permeability.

The other really HUGE thing is thanks to Covid 19 is that this same gene TMPRSS2 is used by the spike protein to enter cells and the research into this has exploded with unlimited funding and fast tracked research it. COVID also uses Testosterone so PCa and Covid are so intertwined that we are learning about PCa fast and furious.

Unfortunately I haven’t studied p53 gene but it is one of the most important anti cancer fighting gene.

[cesces]

"Enzalutimide and apalutamide actually block this genes sction preventing cell permeability."

Do you know what kind of permiability to what? And how this prevents cancer?

[HopingForTheBest1]

How about using the Guardant 360DX liquid biopsy test? Is this an IHC diagnostic tool?

[cesces in reply to HopingForTheBest1]

I was wondering the same thing