Some here on the board have successfully revisited previously "failed" chemos for a while after other therapies were tried. I haven't encountered any research that explains this but it might be a case of different therapies pushing the cancer in different directions and sometimes it gets pushed back into a mode where a previous therapy can be effective again. That's a highly uneducated guess based on how it is thought that
Herceptin increase a cancer's reliance on estrogen and ant-estrogen therapy can increase a cancer's reliance on Her2 pathway. So...a sliding scale of sorts that some suggest is best dealt with by blocking both. Again..I don't know if there is a sliding scale between other chemos. Seems possible.
But I am aware of some research behind revisting failed chemos (previously given in a maximim tolerated dose scenario) with a lower dose, more continuous approach called metronomic chemotherapy. The idea is that a lower dose reduces toxicity and requires less, if any, break from the chemo which could otherwise give the cancer time to recover/grow resistant to the drug:
LINK
The other approach that can make a "failed" chemo work again is chronotherapy, giving the chemo at the time of day that is least toxic and most effective:
LINK
Of course, if there is merit to these approaches, it might be best to employ them both from the beginning..since patients may not be experiencing a failure of the drug, but a failure in delivering the drug optimally. Avoiding/using alternatives to
glucocorticoids and
opiates/opioids could be additional steps towards preventing delivery failures.
Sorry..it's like you pulled my string.
Observations from a totally uncredentialled, but very concerned son.