A recent thread of mine.
My Mother Died - Miscellaneous and Personal Stuff I Must Share - Straight Dope Message Board
I remember an episode of PBS’s NOVA which details how certain cancers spread…metastasize…but the metastases essentially remain dormant due to a restrictor hormone from the main tumor. When the main tumor is neutralized due to surgery, chemo, or radiation, the loss of restrictor hormone stops holding the inert metastases in check, leading to a new outbreak of cancer.
That’s not how I understand metastasis works. I don’t think the tumor releases a restricting hormone that causes dormancy, and my understanding is that the factors leading to metastasis are pretty complex. I hope our knowledgeable medical folks will respond.
I’m very sorry about your mom.
NOVA transcript regarding “endostatin”.
NOVA | Transcripts | Cancer Warrior | PBS
Long transcript!
@nelliebly this is not my field but reading up quickly it appears sometime some cancers.
Cells produce compounds that can drive new blood vessel growth (angiogenesis) and that can suppress it … regulating it to fit needs. Cancer growths have those factors go out of whack and can only grow if the ones that promote angiogenesis are greater than the ones that suppress it. Apparently some stable tumors have a large amount secreted of the suppression one? One of which is endostatin. Which in some cases keeps other tumors from developing supporting blood supplies. Interesting.
What I do understand just enough to know how much I do not understand is that there is whole lot of “cross talk” between primary tumors and metastases:
It seems possible that some cancers (eg. stomach, gastric) actually begin in the bone marrow and only secondarily go the target organ.
This highly cited - 1650 times - article from SCIENCE some years ago, demonstrated that the bone marrow may actually be a source of cancer cells that go to the stomach and lead to a stomach cancer there. The authors conclude, “These findings suggest that epithelial cancers can originate
from marrow-derived sources and thus have broad implications for the
multistep model of cancer progression.” In other words, this could apply to many common presumed primary sites of cancer such as the GI tract, lungs, breasts, and other “epithelial cancers”.
It seems, perhaps, to have become a bit of a paradigm with lots of follow-up papers in the years since in SCIENCE alone. I have most definitely not kept up with it.
FWIW, my point is that we may not be looking in the right place to find out when/how a cancer begins, "hides’, or “returns” years later.
Very interesting. Apparently at least 18 years later it was still not clear if bone marrow derived cells (BMDC) are the source for gastric cancer stem cells (GCSC) or not.
These findings suggest that BMDCs may be a source of GCSCs. However, more rigorous and adequate evidence is needed to support this conclusion …
But the “suggestion” built at this point seems quite strong! And they minimally are involved as supporting players.
My search so far fails to find anything more recent.
This was to be my layman’s guess as well, but as is often the case, S_O_A_T has already answered with much greater eloquence and depth than I would have been capable of.
Turner Classic Movies has aired a very entertaining self-produced documentary called “The Sid Story”, which was basically a man’s autobiography on film. At the end of the movie, it mentioned that shortly after they stopped filming, his wife was diagnosed with breast cancer, and underwent a mastectomy with no further treatment warranted. Several years later, she had her “annual” and was given a clean bill of health, and then about a month later, he came home from a trip to the grocery store and found her dead. An autopsy revealed that she had a heart attack - and every organ in her body was riddled with cancer.
Some types of colorectal cancer are also notorious for doing this kind of thing.