Oxaliplatin: What are the effects of dropping it from FOLFIRINOX?

I can't speak to your specifics, but can describe my own situation. I am stage 4, with no node involvement but several small mets visible when I had a staging laparoscopy in early April. Because of the mets, I do not qualify for any type of radiation or surgery. So far, I've completed 14 chemo cycles. We have decided that I'll continue as long as I want or as long as I'm getting results; when results start to lag, I can switch regimens and, later, look for a trial if I want.

My first eight cycles were Folfirinox. The first was at 80 percent of typical dose (reduced because I'm over 70, and the oncologist pointed out that the full dose was tested on people much younger than me); all other doses have been at 60 percent of typical due to the rough reaction I had to the first cycle. Beginning with cycle 9, the oxaliplatin was dropped from my regimen. My oncologist said that he prefers discontinuing it before neuropathy gets so bad that it's permanent and crippling. Please note, and this is sort of a reply to another post on another thread, we are not really striving for a cure, given my age; we're working toward stable disease and length and quality of life. I'd take a cure! But no guarantee it'll happen.

Having described all that, I can tell you that my CA 19-9 has gone down steadily since it first was taken in mid-March. I started at 1736. The most recent CA 19-9 for which I have a result is 35. It was taken before chemo no. 13 on 11/14, so it represents four cycles minus oxali. So, in answer to your question, in my case dropping the oxaliplatin didn't cause an increase in CA 19-9. But I'm only one patient. Pancreatic cancer tends to respond to platinum-based drugs, and omitting it may be linked to the rise in your CA 19-9. Many factors can make it go up, but those of us with pancreatic cancer are sensitive to an increase because yes, it can indicate a recurrence. So I would ask my oncologist to pursue a cause for that increase, in case something has developed that needs to be treated. I hope you can find the cause!

From https://www.sciencedirect.com/topics/medicine-and-dentistry/ca-19-9-antigen#:~:text=Interference%20of%20heterophilic%20antibodies%20causing,of%20CA%2D19%2D9.

"Elevated CA-19-9 levels usually precede the radiographic appearance of recurrent disease, but confirmation of disease progression should be pursued with imaging studies and/or biopsy. CA-19-9 can be elevated in many types of gastrointestinal cancer, such as colorectal cancer, esophageal cancer, and hepatocellular carcinoma. Apart from cancer, elevated levels may also occur in pancreatitis, cirrhosis, and diseases of the bile ducts. It can be elevated in people with obstruction of the bile duct. In patients who lack the Lewis antigen (a blood type protein on red blood cells), which is about 10% of the Caucasian population, CA-19-9 is not expressed even in those with large tumors. This is due to deficiency of the fucosyltransferase enzyme that is needed to produce CA-19-9 as well as the Lewis antigen. The use of a combined index of serum CA-19-9 and CEA (CA-19-9+[CEA×40]) has also been proposed for screening of cholangiocarcinoma.

"Interference of heterophilic antibodies causing false positive CA-19-9 results has been documented, and usually treating the specimen with heterophilic antibody-blocking agents can eliminate such interference. Patients with acute or chronic pancreatitis may also have elevated levels of CA-19-9. In addition, pulmonary diseases may also elevate CA-19-9 levels. Liver cirrhosis, Crohn’s disease, and benign gastrointestinal diseases can also increase CA-19-9 levels."

I'm not a medical professional; I just googled for reasons why CA 19-9 could be elevated. There are a bunch. That's what makes CA 19-9 a tricky tool to use for definitive diagnosis. On the other hand, I've always heard that the CA results are more reliable to track disease/treatment progress once you have a firm diagnosis. That's why, if my CA 19-9 were starting to rise, I would be pestering my oncologist for more assessment to pin down why.

Speedy update: I just got my CA 19-9 back from Tuesday, which was taken after chemo cycle 13 but before cycle 14 was administered. It's now down to 29, which is 6 points lower than the test taken 11/14. It also represents, now, five cycles without oxaliplatin. So again, I'm just one person reporting continued results without oxali. Others have seen a rise after discontinuing oxali. Correlation and causation are two different things, both in my case and others' cases. Correlation is not the same thing as causation. If the OP's and others' results continue to rise, it's worth pursuing the causation, as I will if/when mine rises.

I'm curious to know about Oxaliplatin too. My husband had a distal pancreactomy and splenectomy in July and is doing adjuvant chemo for six months. His 6th treatment was today, and he had a reaction to the Oxaliplatin - red face and neck, nausea, tingling tongue, lips and hands, stinging lower back and legs, restless legs, high blood pressure, itchy hot hands and feet, tightness in jaw, abdominal pressure and light headedness. They stopped the infusion immediately and an entire team showed up with oxygen and intervention medicines (Benadryl, Pepcid).

The doctor said that this was a reaction to the Oxaliplatin, so they didn't continue with it. This is his second reaction to Oxaliplatin - the first time was after treatment #3, he had a fever which they said was from the Oxaliplatin after they ruled out every kind of virus and bacteria.

The nurse had said that since this is his second reaction, they might not want to continue with the Oxaliplatin. However, I just saw the notes in the portal which indicate that they want him to pre-medicate with steroids and Claritin before the next treatment.

Ironically, just before the treatment, I had asked about the efficacy of the chemo regimen if the Oxaliplatin was removed and the nurse practitioner said that it would be fine, they usually remove Oxaliplatin later in the regimen if neuropathy worsens. She said that they like to start with the 3 meds.

Today was very scary. I was really hoping that they'd remove the Oxaliplatin going forward.

Has anyone else had this experience? If so, were you successful with the pre-med steroids and Claritin? Thank you.

@lisn, my response will be of limited use bc I had no problems with oxaliplatin -- but that might be bc I was always pre-medicated.

I was always pre-medicated with steroids (dextromethasone) before the infusion and I also took a dose on the morning of Day 2 and Day 3. (My pre-meds also included generic Zofran, for nausea.)

I was told to take one tablet of Claritin on Days 1 thru Day 5, and I did.

I also received, with infusions 2 thru 8, a shot of atropine along with the irinotecan, because without it I felt intense bowel urgency. Even with the atropine, the irinotecan hit me hard -- my eyelids twitched, I developed post-nasal drip, and by the final infusion I had a weird sensation of my legs being too heavy to move. ***All of these side effects dissipated within a few hours,*** but I'm mentioning them in case the info is of use.

Apologies for going slightly OT.

I'm curious to know about Oxaliplatin too. My husband had a distal pancreactomy and splenectomy in July and is doing adjuvant chemo for six months. His 6th treatment was today, and he had a reaction to the Oxaliplatin - red face and neck, nausea, tingling tongue, lips and hands, stinging lower back and legs, restless legs, high blood pressure, itchy hot hands and feet, tightness in jaw, abdominal pressure and light headedness. They stopped the infusion immediately and an entire team showed up with oxygen and intervention medicines (Benadryl, Pepcid).

The doctor said that this was a reaction to the Oxaliplatin, so they didn't continue with it. This is his second reaction to Oxaliplatin - the first time was after treatment #3, he had a fever which they said was from the Oxaliplatin after they ruled out every kind of virus and bacteria.

The nurse had said that since this is his second reaction, they might not want to continue with the Oxaliplatin. However, I just saw the notes in the portal which indicate that they want him to pre-medicate with steroids and Claritin before the next treatment.

Ironically, just before the treatment, I had asked about the efficacy of the chemo regimen if the Oxaliplatin was removed and the nurse practitioner said that it would be fine, they usually remove Oxaliplatin later in the regimen if neuropathy worsens. She said that they like to start with the 3 meds.

Today was very scary. I was really hoping that they'd remove the Oxaliplatin going forward.

Has anyone else had this experience? If so, were you successful with the pre-med steroids and Claritin? Thank you.

I'm not a doctor. I'm just giving my thoughts for what they are worth.

If it was me and I had had a 2nd serious reaction to the oxaliplatin, like your husband has had, I think i would choose not to have the oxaliplatin again.

I believe if you take away the oxaliplatin, that it just makes sense if you take away 1/3 of your army (one of the 3 drugs in FULFIRINOX) to fight the battle, you are reducing your chances of winning the battle.

You and your husband are the ones paying for the treatment. It should be your husband's decision. We have to balance quality of life and attacking the cancer.
My experience: I'm stage 2b (not sure if still am), with most common type of pan cancer. Diagnosed 6/7/23. I now have encasement around my duodenal artery and main hepatic artery (did not have this at beginning).
I had 7 treatments with FULFIRINOX (surgery planned for after chemo).
The last 5 of those treatments were only 50% oxaliplatin, because of jaw pain.
Before my 8th treatment, I told my oncologist I couldn't do the oxali unless it was reduced (because of jaw pain a week of tingling in my left toes)-she didn't think it would kill any cancer cells if we reduced it, and thought I would still have the side effects- I told her if she couldn't cut it in half, I wouldn't take it-so she didn't give it to me.
When my surgeon found out I didn't take the oxali with the 8th treatment, she was very disappointed. She thought any amount of oxali would have helped me. She said there have been no studies done on taking FULFIRINOX without the oxali, (When she said this, I think she was referring to my situation of being 2b stage) so her and the oncologist discussed it and they thought it best not to stay on the FULFIRINOX without the oxali (which I had been hoping they would let me do).
They switched me to gemzar/abraxane, so I took gemzar/abraxane for my 9th chemo, for the first time yesterday, and will continue to have it every two weeks until I've had 12 chemo treatments total. (which means 3 more gemzar/abraxane treatments and then planned surgery, unless something else comes up)
My 9th chemo was delayed a week, because insurance needed more time to approve the new chemo plan.
I get my CA19 tested every 2 weeks before each chemo. Since I stopped the oxali, my CA19 had gone up 5 points- I believe for me, it is because I stopped the oxali.
I have a friend who went through chemo for her pan cancer years ago. She is now taking an anti-seizure pill, twice a day, for the neuropathy in her hands and feet. I don't want to have to do that in the future-that is the reason I said no to any more oxaliplatin. I believe for me, stopping the oxaliplatin means I am not fighting the cancer as well as I could with the oxali, but I made the decision to stop it because my quality of life is more important to me, and I'm not a person to take chances. I don't know if I made the right choice, but it's a choice I felt was right at the time, and for now I'm okay with my choice. I'm doing the best I can with my decision making-all I can do is my best.
You are doing the right thing to ask other's veiwpoints.