Forums » Smalltalk » AMA: Molecular Testing in Cancer

Hi friends!

I have a rather unique job doing a very specific type of cancer testing that falls under the umbrella of “molecular tests”, which look at the DNA, RNA, proteins, and other molecules surrounding tumors in order to help cancer patients get the right treatments! It’s a really important job, but a lot of people don’t even know it exists, so I’m here to answer any and all questions about cancer, cancer testing, or pathology and lab testing in general!

Oh my god that's such an interesting job

What kind of study did you have to do to get that job and what does your average day at work look like?

Hi, thanks for asking!

There is a somewhat specialized college program for what I do, called by various names across the world: Medical Laboratory Sciences, Clinical Laboratory Sciences, and others. I joined the field through a bit of a nontraditional route, I got a bachelor of science degree in general biology, and then did a lot of on-the-job training, and then got an additional certification for the specialty I’m currently in (molecular biology).

The type of test that I specialize in is called FISH, which stands for Fluorescence In-Situ Hybridization. I use a fluorescence microscope it to look at the genes in cancer cells to determine if there are certain mutations present that can affect the patient’s treatment. The process to make the microscope slides takes about 16-24 hours, so usually that’s done overnight, and the first thing I do in the morning is result out the slides that were made the day before. After that I start making slides for the next day, which is a process with a lot of little steps that culminates in applying a chemical to the patient tissue on the slides that makes certain genes glow on the microscope. I also have a digitized microscope that takes images of the tissues, which can be used or analysis or for storing images of slides that have already been completed. After that, it’s a lot of sorting paperwork, fulfilling client and pathologist requests, and setting things up for the next day!

Wow that's amazing! That really is some interesting behind-the-scenes work you do there! I'm not a cancer patient, but I've always kind of wondered what happens to my blood samples and so forth after collection

That sounds so cool and exciting! My brief stints with histology and microscopy in med school were NOT successful .

Do you feel any sort of psychological/mental touch when you find a test that’s abnormal or malignant? And if you don’t, how do you deal with it?

Do you do post-mortem diagnostic tests, too?

This is SO COOL.

How long have you been in this field? And... how long has it even existed as a job people could have, in this form?

Hi!

I do hear that a lot from medical professionals who didn't specialize in pathology, funny enough. There's just so much more to laboratory medicine than most nurses and physicians get in their education, it's astounding.

In my lab specifically, we have a few sayings. First is, "If it's not cancer, it's in the wrong lab." The type of testing that I do is pretty expensive to run, so I only receive a case once it's been reviewed by a surgical pathologist who has confirmed that there is some sort of malignancy in the tissue. Most of the testing I perform is to answer questions like "What kind of cancer is this?", "What kind of prognosis is the patient looking at?" and "What kind of treatments will be most effective against this cancer?" So if there's no cancer, we don't test it!

The second pertinent saying we have is "The best result for the patient is the correct result." While it might be tempting to fudge the numbers just a little bit in order to give the patient a more 'favorable' outcome (count this cell instead of that one, maybe artificially inflate this number by 0.05, etc.), really all that does is make things worse for the patient in the long run. If a positive EGFR result means that the tumor is more aggressive, then we want EGFR to be negative, right? Well, not necessarily, because if it truly is positive, then giving a false negative robs the patient and their family of having an accurate prognosis, and prevents the patient from being able to use what time they do have left to the fullest (spending time with loved ones, end of life planning, etc).

So I suppose the short answer to the first question can be worded thusly: Every result I handle is malignant in some capacity, but the knowledge that what I do is providing vital information to oncologists, patients, and families so that they can make informed decisions about patient care helps me keep my sense of purpose, even in the face of unfavorable outcomes. I also volunteered with a hospice organization in college, so maybe I'm just an old hat when it comes to end of life care.

And to answer your final question, the answer is a solid Sometimes. Usually the cold ischemic time for autopsy and postmortem cases is long enough that specimens start experiencing DNA degradation long before they get to me, and since I rely on intact DNA to run my specific type of testing, the results we get from those cases are usually unreliable at best, uninterpretable at worst. There are other molecular tests that are a little more accepting of postmortem specimens (immunohistochemistry comes to mind, which stains for protein expression, but even that has limits) which can look at some of the same things my tests do, just at a different level.

Hi!

Presently I've been doing this for about 4.5 years. When it comes to this specific type of testing, there's only one person in my lab with more experience than me (others have more general lab experience, but they recently transferred to my department), and she's been doing this for 20-ish years. FISH testing itself has been around since the 1980's, and although I'm not sure exactly when it started being used for cancer testing specifically, I do know that it has been used to diagnose genetic disorders like Prader-Willi syndrome and Cri-du-Chat before that.

Thank you for answering my question! Have you noticed it changing over the last 4 years? New equipment, etc?

Absolutely! This is a field that is constantly evolving to keep up with new technologies and industry standards, whether that means streamlining our workflow or adopting new machinery.

During the worst of Covid, the FDA released a special authorization for use of digital pathology platforms, so that pathologists could make diagnoses based on scanned images of slides, instead of the physical glass slides themselves, during quarantine. Because cancer doesn’t take days off, not even for a global pandemic. Now those platforms haven’t gone away, even if the global lockdown has. So now we can take what we’ve learned about digital pathology and build on it by doing things like expanding the scope of digital analysis to include multiple test types, adopting a centralized program so that multiple labs can compile slide images in one place for easy reference by inside and outside physicians, and using AI software as a tool to assist in arriving at more accurate results.

That's amazing!! Thank you again for that answer!