Tell me about "stem cell transplants" (cancer).

Factual Questions
1

This is going to be a rough thread for me, but here goes:

Someone very close to me was diagnosed last January with a brain tumor (medulloblastoma?). She had already had one as a girl, about age 12 or 13. The first procedure was to head down to the Mayo Clinic, surgically remove the tumor, and have her go through six rounds of week-long chemotherapy. She got through this one okay, and finished her last chemo roughly July or August. The MRIs she gets show the tumor is gone, except for a tiny white spot the doctors feel is just residual scar tissue.

Fast forward to early November, when she has a follow-on MRI. The little white spot had grown, and after some testing we find out it is, in fact a second tumor. The new plan was to give her a few more rounds of chemotherapy to try to shrink this tumor down to where they would turn to a “stem-cell transplant”.

She explained it to me as this: they “harvest” stem cells by taking blood from you. Then they give you an ultrahigh dose of chemotherapy (a weeks’ worth in three days). Immdiately after that, they transfuse your own stem cells back into you. She said they were hoping to get 5-10 million stem cells. But I just took a call that they didn’t get enough stem cells, and may have to go back home for awhile.

A few questions, and by God I’ve got a lot of them, but I’m looking for some insight–especially if any Dopers have had to go through this before:

[ul]
[li] Exactly what are these stem cells, and just what do they do? I can understand transfusing red blood cells back in to fight fatigue, but what makes these so special?[/li][li] If she doesn’t have enough, can I give some to her? Or mayber her parents, or sisters?[/li][li] If they don’t have enough because of so much chemotherapy, can they still press forward with the procedure?[/li][li] Is there a typical length for recovery? It seemed that her first tumor, she was making great progress in therapy in the two months after the last chemo. Is it a case-by-case thing?[/li][li] My biggest question: are these typically done with good results, or is this some sort of “last resort”?[/li][/ul]

She won’t see the doctors until tomorrow, and I will be waiting with bated breath for a response tomorrow night. She’s not a doctor, and between her parents getting confused with what’s going on, and the doctors maybe oversimplifying things, I’m not sure what to expect. . . Just going day by day at this point.

Tripler
Much obliged, guys. . .

2

They’re the progenitor cells in the bone marrow which give rise to mature blood cells (red blood cells, white blood cells which fight infection, and megakaryocytes, which produce platelets that aid in clot formation). A stem cell is undifferentiated - it can divide, and the daughter cells it produces can go on to become ANY type of blood cell.

That’s not usually done in cancer cases other than leukemias and lymphomas, no. Doing that is the equivalent of an organ transplant, and she would need to take immunosuppressive drugs for the rest of her life. And it’s not easy to find a compatible stem cell donor, either.

The idea behind stem cell transplantation in cancer therapy is that the limiting factor in chemotherapy treatment is usually the bone marrow - high doses of chemo kills the essential cells in the bone marrow (and thus the patient). But if you collect the patient’s stem cells first, you can give very aggressive chemotherapy, then give the stem cells back to the patient once the chemotherapy is concluded. The transfused stem cells will re-enter the bone marrow and grow, and the the patient will regain normal bone marrow function. Bascially, it’s a way to overcome the dosage limitations of “conventional” chemotherapy.

Not until they can collect enough stem cells. But the stem cells are stored frozen, so they can let her bone marrow rest for a bit, then re-stimulate it, collect more stem cells the second time around, and combine those with the ones they already got to get enough total stem cells to move on to the next phase. This just means her treatment will be delayed a bit, not that they can’t do it at all.

Yes, it’s a case-by case thing. In any case, once she undergoes the high-dose chemotherapy and subsequent stem cell transplantation, she won’t be able to leave the hospital until the stem cells have started growing in her bone marrow, and her white blood count and platelet count have recovered enough to prevent bleeding and infections - that can take 2-4 weeks.

Results vary with the type of cancer being treated. It’s still very much an experimental treatment for recurrent or advanced medulloblastoma, but preliminary results do show promise of significantly increased survival time. However, this probably isn’t going to be a curative procedure.

You might want to check out this website: National Cancer Institute - Peripheral Blood Stem Cell Transplantation

My thoughts go out to you, Tripler. Please don’t hesitate to ask any questions you might have; I’ll do the best I can to find the answers for you.