What is (or is there any) relationship between cancer, pregnancy, and a fetus?

November 29, 2009 3:06 PM

What is (or is there any) relationship between cancer, pregnancy, and a fetus?

I have been wondering for some time about the relationship between a pregnant mother with a late stage (3 or 4) cancer, and how this affects a fetus, if at all. Does it depend on the type of cancer? Are cancerous cells ever transferred from a mother to a fetus?

Have there been any studies about increased risk of certain cancers because of pregnancy? (i.e., not just familial history, but with the added factor of being in a womb of someone with late stage cancer)

I am curious about cancers in general, but bonus insight about melanoma would be good to know. My mom found out that she had stage 3 malignant melanoma the morning she went into the hospital to deliver me. In my late 20's now, I'm in very good health, and am conscious of sun-exposure and changes to moles, but still sometimes wonder about the effect of having cancer while pregnant.

posted by raztaj to health & fitness (7 answers total)

These folks may have some helpful resources.
posted by Sidhedevil at 3:09 PM on November 29, 2009

Sidhedevil - thanks for the link. From what I've found on that site, it seems to be geared towards dealing with cancer while pregnant, and is predominantly focused on maternal care. While important, I'm mostly looking for information on effects on a fetus in the womb, and cancer incidence later in life. I'll explore the site some more, but haven't really had luck in finding out this sort of info on that site... :\
posted by raztaj at 3:16 PM on November 29, 2009

Sorry, raztaj--I thought they had more links to actual research. Either I'm misremembering where I came across those, or they revamped their website since the last time I accessed it.
posted by Sidhedevil at 3:22 PM on November 29, 2009

Molar pregnancy can result in Choriocarcinoma.
posted by phrontist at 3:37 PM on November 29, 2009

Yes, it is possible -- but extremely rare -- for the mother to transfer cancer to the unborn child. (more)
posted by Rhomboid at 3:55 PM on November 29, 2009

This isn't quite what you're asking for, but if you have breast cancer, they often do an "ER/PR" (estrogen receptor, progesterone receptor) test on the tumor when they remove it. Some breast cancers have receptors for these hormones, meaning the cancer is stimulated by those hormones and can grow faster when hormone levels are higher.

I was diagnosed with breast cancer a couple of years ago and am not planning on having kids for a few more years, and I was told that often young women who get cancer and are ER/PR-positive will sometimes have a recurrence of their cancer when they get pregnant because the change in hormones reactivates the cancer cells (which were presumably missed by an earlier lumpectomy/mastectomy). My doctors had anecdotes about other girls my age (mid-20s) who went through that, which of course scared the crap out of me.

I didn't hear anything about risks to the fetus. The main concern seemed to be on keeping the mother alive until after delivery, when they'd begin chemo/radiation/etc. treatments that aren't safe for the fetus.

I don't know anything about skin cancer and whether it has any interaction with hormones, though.
posted by katieinshoes at 4:39 PM on November 29, 2009

Here is the article mentioned above by Rhomboid: Immunologically silent cancer clone transmission from mother to offspring

If your mother's melanoma had been transmitted to you it would have almost certainly manifested while you were still an infant.

As I understand it, the only thing you have to worry about is increased cancer risk because you have a family history. That is, you may very well be carrying one or more maternally-inherited mutations that predispose you to develop malignancies. So use sunscreen, don't smoke, and eat right. Other than that, you can sleep easy.
posted by chrisamiller at 4:50 PM on November 29, 2009