Brief Answer:
It hasn't been shown to work for brain cancer.

Detailed Answer:
I read your question carefully and I understand your concern.

Ip - 6 is an antioxidant. It is thought that it helps in preventing cancer however there is no clinical trial, no study to have shown that effect. So while there is no harm in taking it as it is a component found in your food there is no proof of its efficacy in preventing cancer.
As for treating it, again like for prevention there is no proof and in an already developed tumor I am pretty certain that it can't stop its progression.

As for substituting it with the steroid that is not possible, even if in the future studies show some kind of benefit, the mechanism of action is different, it is not a substitute for it. In brain cancer the steroids are used mainly to address the swelling around the tumor.

So the answer I am afraid is no, it hasn't been shown to work for brain cancer.

Let me know if I can further assist you.

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Brief Answer:
Not as effective

Detailed Answer:
I am sorry but there is no such replacement. Mannitol perfusions are also used for brain swelling, but it is not effective as steroids and anyway it cannot be used for more than a few days.

I remain at your disposal for other questions.

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Brief Answer:
Read below

Detailed Answer:
It would be useful if you could provide the side effects. Steroids can act on many different systems and cause different side effects in different patients. Also at times tumor effects may be mistaken with medication side effects.
They may affect the stomach for which ginger, chamomile or yogurt can be used (though I would advise to use Omeprazole, a medication). Can raise blood pressure for which garlic, cinnamon, flax seed may be used (or blood pressure medication of course). They may cause mood changes for which St XXXXXXX wort may be used. So it depends, but at the end of the day natural remedies can achieve little, steroids do have many side effects.

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