Onc says NO to using Cal/Mag to minimize neuropathy - help?

[SoCalSaz]

Hi all,

First round of XELOX starts tomorrow... so I asked my oncologist today about using calcium/magnesium infusion to prevent neuropathy per the suggestion I received in a recent question about preparing for chemo. She said that it was used for awhile but studies showed that it reduced the efficacy of the chemo -- but my sense is that those concerns were subsequently considered unfounded. Can anybody confirm this for me? (Better yet: point me to a specific study/studies that I can forward to her?) Is it something worth calling up her office and pushing her on in the morning (my infusion isn't scheduled till the afternoon)? In the event that I can't convince her, will taking a Calcium/Magnesium supplement still give some benefit?

Thanks for thoughts/suggestions. I'm an editor/writer and make a living by my keyboard, and so am especially worried about this side effect.

[jdepp]

See the conclusions in bold font:

Eur J Cancer. 2010 Nov 8. [Epub ahead of print]

The effect of prophylactic calcium and magnesium infusions on the incidence of neurotoxicity and clinical outcome of oxaliplatin-based systemic treatment in advanced colorectal cancer patients.
Knijn N, Tol J, Koopman M, Werter MJ, Imholz AL, Valster FA, Mol L, Vincent AD, Teerenstra S, Punt CJ.
Department of Medical Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; Department of Pathology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.

Abstract

BACKGROUND: Peripheral sensory neurotoxicity is a frequent and potentially debilitating side effect of oxaliplatin treatment. Calcium and magnesium (Ca/Mg) infusions are frequently used to prevent this toxicity. However, concerns about a negative impact of Ca/Mg infusions on outcome have been raised. We retrospectively assessed the effect of Ca/Mg infusions on the incidence of neurotoxicity and on clinical outcome in advanced colorectal cancer (ACC) patients treated in the phase III CAIRO2 study.

MATERIALS AND METHODS: Seven hundred and fifty five previously untreated ACC patients were randomised between treatment with capecitabine, oxaliplatin and bevacizumab or the same combination with the addition of cetuximab. Patients were retrospectively divided into two groups: patients in the Ca/Mg(+) group received Ca/Mg at least during their first treatment cycle, and patients in the Ca/Mg(-) group did not.

RESULTS: Seven hundred and thirty two patients were evaluable for this analysis. The Ca/Mg(+) group consisted of 551 patients, the Ca/Mg(-) group consisted of 181 patients. The incidence of all grade neurotoxicity in the Ca/Mg(+) group and the Ca/Mg(-) group was 85% and 92%, respectively (p=0.02), and the incidence of grade⩾2 neurotoxicity was 40% and 45%, respectively (p=0.22). The median PFS in the Ca/Mg(+) versus Ca/Mg(-) group was 10.1 versus 10.7months (p=0.92), the median OS was 19.8 versus 20.7months (p=0.10), and the response rate was 43.1% versus 50% (p=0.11), respectively.

CONCLUSIONS: In this largest retrospective analysis to date we observed that Ca/Mg infusions significantly reduced all grade oxaliplatin-related neurotoxicity. Ca/Mg infusions did not affect the clinical efficacy of treatment.


http://www.docguide.com/news/content.ns ... s=21067912

[joeyooser]

For what it's worth, my onc suggested taking tums and a magnesium supplement 1 hr before treatment and afterwards once I started having neuropathy. I'm not sure it did anything - the clinical data I believe is based on IV infusion of these before the infusion of oxaliplatin.

[elissa]

My husband is a pt at MSKCC in NY and they outright refuse to give Cal/Mg infusions. They also ask that he not take any supplements that are antioxidents. They do not want anything that could interfere with the chemo. I too have a lot of concern about not having these infusions. I worry about how bad the neuropathy can get. So far, he is on his third round, and he has been lucky. I do worry about what may happen as he gets further into his treatments. I may have to really put up a fight if he starts having neuropathy. Good luck. Let us know what happens.
Elissa

[gfpiv]

I got some rough neuropathy at FOLFOX treatment #7 or 8 (esp. hand and foot tingling/paresthesia), but for the next 5 cycles I just took a couple Rolaids before and after getting the Oxaliplatin infusion, and it seemed to reduce the neuropathy quite a bit. (Or maybe it was just coincidence?)

Of course it wasn't a complete panacea; I did get a fair amount of neuropathy later, which was at it's worst 6 weeks after my twelfth/last Ox cycle, though it has gradually gotten better over the past few months since then.

Rolaids has both Calcium and Magnesium; Tums is Calcium only (per joeyooser's post). If your onc makes a stink about cal/mag infusions, then you could always just take cal/mag orally (perhaps even without telling him? perish the thought!). I certainly understand his logic about not supplementing with antioxidants during chemo, but that's different.

-Chip

[beccab1]

I don't know much about Cal/Mag and my husband's onc didn't suggest it. I do want to caution that since you are doing xelox, be careful taking anything like tums or rolaids because they can affect how well the xeloda is absorbed if you would take them too close together.

Goodluck tomorrow! Wish you the best!

[EdFromCT]

My ever-cautious oncologist also steered away from calcium/magnesium supplements on the grounds that they might reduce the efficacy of chemotherapy. He preferred to ask for detailed information about neuropathy symptoms, and to reduce or eliminate the oxaliplatin dosage accordingly. If you go this route, just keep in mind that the neuropathy may continue to slowly worsen for several weeks after the end of treatment, so it might be a mistake to "tough it out" if things are getting bad.

If you are concerned about efficient typing, I suspect that the important thing is to back off when there is at most mild numbness in the fingertips. Don't let things progress to the point of significant pain, or the loss of "propriocentric" nerve information that lets you know where your fingers are located. In my own case, things progressed to the point of slight numbness in the fingers, and significant loss of sensation in the toes. After a year, my fingers (and typing speed) are back to normal, but the toes are still a little numb. It's not a real problem, but if I walk barefoot it usually feels somewhat as if I'm walking on sand.

-Ed