no shrinkage, no growth - is Carbo not working, but Alimta is ? - 1264330

Both drugs are intended to kill cancer cells; quite a while ago it was discovered that a platinum agent such as carboplatin works best in combination with a second drug. It's not possible to say anything other than that the combination has kept your cancer stable. After first-line treatment is completed, Alimta is often effectively used as a single agent.

JimC
Forum moderator

Yes, exactly. They both work to shrink the cancer, but short of shrinking the cancer, sometimes it just works effectively enough to keep the cancer from growing. Because of that, while we prefer to see tumor shrinking, the next best thing is stability.

But we can't separate which cancer drug is doing what in a combination.

-Dr. West

Although there are always exceptions in individual cases, it isn't normally continued beyond six rounds due to diminishing returns and cumulative toxicity. As Dr. West has said:

"One of the longstanding ideas in lung cancer management is that you exhaust the benefit of first line combination chemotherapy after 4-6 cycles of treatment. This is based on a few trials that showed no survival benefit for treating beyond that point, as summarized in this early post I wrote all the way back in my first few months of doing this (OncTalk days, pre-GRACE). This standard of care is based in part on the premise that the incremental adverse effects may escalate faster than any incremental benefit for a platinum-based doublet. With cisplatin, cumulative nausea, fatigue, risk of significant kidney damage, neurotoxicity, and overall “platinum blues” tend to make treatment beyond 6 cycles infeasible and disproportionate to any potential added benefits of ongoing therapy. With carboplatin, cumulative cytopenias (low blood cell counts) and a rapidly escalating risk of a severe and potentially dangerous hypersensitivity reaction (which can also occur with ongoing cisplatin but is notorious and almost inevitable with carboplatin) make indefinite carboplatin too challenging and inadvisable."

JimC
Forum moderator

There is certainly no established benefit of it, and it is very clearly not the favored approach, for the reasons Jim noted. That said, there are individualized cases in which it may be considered, but that wouldn't be based on any evidence that it's helpful, and many experts rarely or never favor this approach.

Particularly after the first line of treatment, management of advanced lung cancer tends to be more of a distance race than a sprint. There's no real value in focusing overwhelmingly on the first lap and then burning out your marrow function or causing other side effects that make it harder to manage over a longer distance.

-Dr. West