Tests for evaluating chemo between scans?

[zephyr]

For many people, CEA seems to be a good marker for evaluating the effectiveness of chemo, and a fast, easy lab test that can be done between scans. Unfortunately for some, myself included, CEA is not a reliable marker. My CEA was barely above normal before my CRC surgery, and I was already at Stage 4. I've had the circulating tumor cells blood test twice but they never find anything so that's not a good test for me (plus it's too expensive to be doing regularly). The past 10 months off chemo have been bliss but new nodules are lighting up the scans. My oncologists are recommending Xeloda and while I'm prepared to do it, I'm also wary. I had already developed resistance to Folfox, 5fu alone, and Folfiri, and I sure would like a more proactive way to judge whether the Xeloda is working than waiting for the next scan. I'm bummed: CEA is a dud, CTC is a dud, all lymph nodes tested after 3 separate surgeries were clear ... how is it traveling?!?

Does anyone have any suggestions for a maybe-reliable test (other than to suck it up and wait for the scan)?

Thanks.

[hopie]

I'm guessing you've tried CA 19-9? I remember reading MCV as a potential marker for Xeloda efficacy, but I think it didn't really reflect effect till later weeks. Maybe checking inflammation, WBC, CRP etc. might help? Another possibility might be to look at trends in your bloodwork if you have the data. If you can pinpoint an approximate time for when you have developed resistance, some markers might pop up?

CEA seems to be reliable for my mom but then again rise in CEA might mean cancer cells are dying or growing... CEA is currently on a downward trend, but the studies I've read also suggest that CEA is not necessarily a reliable marker during chemo--scan results do not always match up to them. Then again, there's the issue of the reliability of scans too; everything ultimately relies on pathological response, which we cannot know without surgery.

Sorry I can't be of much help as I'm neither an expert nor someone who has much knowledge in chemistry/biology. But I'm interested in the question of tracking treatment during chemo as well!

[zephyr]

Another possibility might be to look at trends in your bloodwork if you have the data. If you can pinpoint an approximate time for when you have developed resistance, some markers might pop up?

Thanks, hopie, that's a good idea. I have all my labs for the past several years. By tracking the numbers, maybe on a spreadsheet, I will be able to pick up less obvious markers.

[betsydoglover]

How far apart are your scans? Mine were 2 mo apart when first treated for Stage 4, then 3 and then 4. Long time until I went to 6. If your scans are frequent enough, then you don't really need another test.

[zephyr]

How far apart are your scans? Mine were 2 mo apart when first treated for Stage 4, then 3 and then 4. Long time until I went to 6. If your scans are frequent enough, then you don't really need another test.

Since this is a recurrence and a new plan, they're talking about the first scan being 8-10 weeks out but then I imagine they might go back to the every-3-months schedule. I guess I'm just trying to figure out if there's an easy way to avoid a month or two of side effects if the drug stops working. I had a hard time on chemo, and two years of Folfox and Folfiri caused a lot of GI damage that lingers still. Vitamin C IVs helped me keep up my strength, and fasting made chemo tolerable, but it was rough. That said, I am trying to understand CA199. My naturopathic oncologists always includes that test in her orders.

[hopie]

CA 19-9 is an alternative marker! I think it's primarily a marker for another type of cancer but it also works for CRC. I've read about people for whom CEA didn't work but CA 19-9 did. Hopefully it will be a marker for you too.

Looking at trends and correlation might help too; as in, "when things are normal x & y move in the same direction, but when things go astray x goes in the opposite direction."

[boxhill]

Hi Zephyr,

Your sig doesn't say anything about your tumor genetics. Are you MSS or MSI? I rechecked and saw that you are KRAS mutated. sorry.

I don't have anything to offer about testing between scans, although I do sympathize: CEA isn't a marker for me, either, so the question of whether FOLFOX was or was not working was always a mystery. CA 19-9 is primarily a marker for pancreatic cancer, although according to my onc there is some overlap. But he said it can be difficult to get the insurance companies to pay for it.

What I'm wondering about is whether you have any treatment options other than Xeloda, which to my layperson's eyes appears unlikely to work if 5FU didn't, since it is essentially the same thing. That would depend mostly on your tumor genetics. KRAS lets out the anti-EFGR drugs like Erbitux, but what about immunotherapy?.

[zephyr]

Hi Zephyr,

Your sig doesn't say anything about your tumor genetics. Are you MSS or MSI? I rechecked and saw that you are KRAS mutated. sorry.

I don't have anything to offer about testing between scans, although I do sympathize: CEA isn't a marker for me, either, so the question of whether FOLFOX was or was not working was always a mystery. CA 19-9 is primarily a marker for pancreatic cancer, although according to my onc there is some overlap. But he said it can be difficult to get the insurance companies to pay for it.

What I'm wondering about is whether you have any treatment options other than Xeloda, which to my layperson's eyes appears unlikely to work if 5FU didn't, since it is essentially the same thing. That would depend mostly on your tumor genetics. KRAS lets out the anti-EFGR drugs like Erbitux, but what about immunotherapy?.

Thank, Boxhill. You made my point better than I did: if 5fu stopped working, why would xeloda work? That's why I want some sort of interim test. I don't want to be managing side effects if the drug's not working. From what I understand, there's reason to believe that after a long chemo break, it might work again. I don't like it but I don't really have any other choices. I believe the combination of MSI and KRAS exclude immunotherapy options but I'm checking into the Foundation One information.

As for the cost of the CA 19-9 test, if insurance won't pay for it, I might have it done privately. I did a quick search and it looks like the cash price is $58-180 depending on where you go. Life Extension will order it for about $63 and that might be the best deal considering someone will be available to discuss the results with me (nice to have a second opinion of sorts).

[LPL]

Zephyr wrote:
I believe the combination of MSI and KRAS exclude immunotherapy options but I'm checking into the Foundation One information.

Where have you heard that? I thought it was the MSI status and not the mutations that was of importance.. Please share when you find out.

[zephyr]

Zephyr wrote:
I believe the combination of MSI and KRAS exclude immunotherapy options but I'm checking into the Foundation One information.

Where have you heard that? I thought it was the MSI status and not the mutations that was of importance.. Please share when you find out.

Is there an emoticon here to show knocking one's head against a wall? I'm MSS not MSI. Sheesh. Too many acronyms and too much data in my head today. That said, I will absolutely share whatever I learn.

[LPL]

Zephyr wrote:
I believe the combination of MSI and KRAS exclude immunotherapy options but I'm checking into the Foundation One information.

Where have you heard that? I thought it was the MSI status and not the mutations that was of importance.. Please share when you find out.

Is there an emoticon here to show knocking one's head against a wall? I'm MSS not MSI. Sheesh. Too many acronyms and too much data in my head today. That said, I will absolutely share whatever I learn.

Are you looking for this one?

[boxhill]

Love it, LPL!

No, KRAS has nothing to do with suitability for immunotherapy as far as I know. Except, I guess that it might add to the TMB. If you have a high TMB for an MSS person--I think around 12--you might be able to get immunotherapy.

It is true that some people are able to go back on old chemos after a substantial break and they will work again.

Have you explored trials at all?

[debsta]

I would be very interested to know if you are able to track any other lab tests as indicators of chemo effectiveness.

We are just beginning this journey and after only three chemo sessions my husband's CEA has gone from 14.7 to 3.1. While I'd like to believe the chemo is working this well, I worry that maybe CEA might not be a useful marker for him. That is a substantial decline in such a short time and puts him within normal range despite the fact he is Stage IVb with numerous liver and lung mets.

His CA-19-9 has ranged from 10 to 14 and so is not considered a good marker for him. I know his team also watches his LDH levels, which went from 515 to 166, but I am not sure how this relates to his cancer or chemo effectiveness.

His first restaging scan is not scheduled until May 6 per trial protocol, so CEA numbers are all we have to go at this point. I really want to hope the chemo is working but am afraid to have hope based on just one number.

[rp1954]

MCV may have decent performance in standard chemo regimes long term but it is s-l-o-w to reach a stable level, lagging by months on improvements due to chemo; it declines faster for inadequate chemo. Past being in a low noise regime for CEA, CA199, LDH, and ALP, it is the totality and completeness of the spreadsheet for scans, events and adequate bloodwork that allows the best analysis, and potentially, less anxiety. There are many panels that have potential information contributions, influenced by the other data and events, until inflammation and damage related noise dilutes or drowns out a lot of information. We had good results on noise suppression in the modal treatment mode.

There are pools of papers in the literature for each panel's behavior with CRC or related cancers. When literature is combined with enough of your data from before, to train your personal model, then you get the best estimates of the probable situation(s) that you are dealing with.

For mCRC, what's as psychologically important as NED or stable in the bloodwork readings, is the ability to hit back with genuine improvement(s) and home in on improved results, with some assurance that there are more good "rocks" to aim if necessary, rather than "that's all we got". Even in the midst of "bad", 2 or 3 week blood data quickly read and responded to well, can build peace of mind instead of anxiety. It may be best if someone else can do the heavy duty read with any recommendations asap, and you spend just a few minutes reading and absorbing the latest batch's results with a clear direction.

[hopie]

Thanks, hopie, that's a good idea. I have all my labs for the past several years. By tracking the numbers, maybe on a spreadsheet, I will be able to pick up less obvious markers.

hi zephyr, i was wondering if you ever got the time to do this?