Post-treatment follow up for clear cell endometrial cancer

When my endometrial cancer recurred, I talked my oncologist into letting me get the Foundation Medicine liquid biopsy, because I was hoping to see if the new tumors had the same mutation profile as the initial tumor. I didn't manage to talk him into it until the day of my first chemo treatment, so I didn't actually get the blood drawn until right before the second chemo treatment. This test did not detect any of my tumor mutations AT ALL. When I had a CT scan after the third cycle, the tumors had only shrunk marginally, so it wasn't because the chemo had killed everything. I'm a molecular biologist, so I got Foundation Medicine to send me the raw sequence data, and there really was absolutely zero sign of my tumor in the data. So my personal experience is that liquid biopsies are not sensitive enough to be good for anything. But some tumors seem to shed more DNA than others.

Also, the people in the pancreatic cancer forum on this site have experience with the Signatera liquid biopsy, which should be more sensitive than FM. They seem to think that the Signatera test comes up positive well after their CA19-9 starts rising. So even that doesn't really live up to the hype.

Do you know if you have high CA125 when you cancer is present? Mine is only somewhat high, but I'm still finding the test very useful at gauging whether the clinical trials that I've been on are working. But my oncologist never would have ordered it himself. I asked for it. If I ever get to NED status, I'm going to try to get frequent CA125 tests.

I new to all this. I was diagnosed with mixed clear cell serous uterine cancer. I'm just 3 months past therapy. I'm HER 2+. That makes me eligible for a targeted maintenance program.

I'm be following this post.

Denise

@ffr I'd like to welcome you to Mayo Clinic Connect and to our Gynecological Cancers Support Group. I was diagnosed with endometroid adenocarcinoma in 2019 with a recurrence in 2021. While my cancer was not considered an aggressive type it still does not remove the ongoing fear of a recurrence. By the way, my recurrence was found on physical exam in the form of a small polylp-like structure on the vaginal cuff by my nurse practitioner during a scheduled cancer surveillance appointment.

@val64 is a scientist and has a tremendous amount of knowledge that she shares with us. I hope you find her experiences and suggestions to be helpful.

I wonder if you might like to share your oncologist's recommendations for your cancer surveillance?

Thank you for sharing this information. My CA-125 has been tested since the get-go and it has always been normal, so it’s not a marker for my tumor.
There are no genetic markers or hormone connections and my biomarkers, as I understand it, are not the ones that respond to immunotherapy. I was told that a recurrence would be handled with surgery and radiation, assuming that it occurs in places where these options would be possible.

Would I have had to have a blood draw at the time of diagnosis to have a baseline for Signatera? I’m now 2+ years after surgery so maybe I’ve missed the opportunity?

Thank you for sharing. I hope you are recovering well post-therapy. 🤞

I’m not HER-2 and at this point there is no targeted therapy.

Hi Helen. I appreciate your information.

I have been getting bloodwork, CT scans, and internal exams every 3 months. My doctor wanted me to go to 6 months and I agreed to 4 months. However, at my recent appointment I agreed to 6 months moving forward because of concerns for the repeated radiation exposure.

The reason I asked about liquid biopsies is because I thought that looking for tumor markers between scans - or instead of scans - might be a reasonable and healthier way of monitoring. Thus far, my oncologist has not been on board and I wanted to glean some more information before approaching the topic with him again.

Has it been 2+ years since your last treatment, with NED status that whole time? With no maintenance treatment? That seems like a good sign.

It certainly would be nice if there were better blood tests for recurrences, but at the moment there really aren't. It's not for lack of trying.

It would be possible for you to use Signatera; it's custom-designed for each patient based on DNA sequencing of a surgical specimen from their cancer. But if I were you, I wouldn't do it. There's no way to know whether it would detect a recurrence before a 6-month CT scan or before you started having symptoms.

I never chased down how much it costs, but I'm guessing a lot (many thousands). And it's probably not covered by insurance. (To be honest, I agree that it should not be covered.) The main expense for the company is the up-front cost of the DNA sequencing and designing the test. After this, each actual blood test is fairly cheap for them. So I would expect the first test to be the doozy, cost-wise.

Thank you for sharing your knowledge and viewpoints.
Though I’ve been NED these past 2+ years, I know enough about the aggressive nature of my CCC to know that another recurrence is more than likely and that there isn’t really anything out there for me.
The 3 month CT scans were reassuring in a way and I’m having trouble with doubling that time frame. It’s something I will have to learn to live with.
And I guess I misunderstood Signatera because I thought that it would pick up the presence of cancer cells in the blood even before a scan would find something.
I’m always learning.
Here’s to better detection and treatments. (And a cure!!)

You didn't misunderstand. Signatera is definitely intended to pick up a recurrence before a CT scan or symptoms. And it definitely does in some cases. (It can also be used for other purposes, like tracking whether a treatment is working). But it is still an open question what fraction of recurrences can be detected early this way, particularly for cancer types like uterine clear cell carcinoma that have not been studied with this test.

If you read the company's website, they make it sound great, but my feeling is that they're over-selling the test's ability to detect really low levels of cancer. You might want to read other people's opinions about it by searching "Signatera" on Mayo Connect. In particular, there's a post and a number of comments about it on the pancreatic cancer board.

Thank you!!!
I will pursue these suggestions so that I am more aware. 👍