As odd as it seems, my timing in posting about removing chemotherapy ports yesterday was eerily coincidental.
I’ve alluded to this before, but I’m most definitely not a big fan of John Edwards and would never vote for him for President. That being said, I can’t help but feel for him and, even more so, his wife Elizabeth, given their announcement today that Elizabeth’s breast cancer has recurred (see here as well), with a biopsy proving that it has metastasized to a rib. Neither she nor he nor their family deserve this, nor does any patient with cancer. I’ve gotten a few e-mails asking what this means, what Mrs. Edwards’ chances are. For example, here’s one:
This is a pretty noteworthy news item, and I haven’t seen anyone else on scienceblogs really do a post specifically about it. Meanwhile, the news I’ve seen on the subject is throwing around little fragments of vague, garbled medical information in a frankly confusing manner– for example saying that the fact the cancer recurred means it is now “treatable but incurable”, or that the cancer has “retreated into the bone” and that that is somehow a good thing, but not really explaining why any of this is the case or how the underlying medical science for these statements work (i.e. why are they saying recurred cancer is not curable?).
I’m a long-time reader of your blog, and your posts on the science of cancer have invariably been clear and informative; and in fact yours is frankly the only blog I can think of which can be specifically said to have a focus on cancer treatment. It’s not a big deal, but I was wondering if you’d consider trying a post on what is happening to Elizabeth Edwards and maybe interpreting some of these little media-science snippets in the news stories.
Well, I’m flattered, and I’ll try to answer, and do it more succinctly than my usual long-winded style. My usual disclaimer applies: I haven’t taken care of Mrs. Edwards and have no direct knowledge of her case. What follows is a general discussion of patients who present as she did, with my information coming from news reports.
First off, saying that a cancer is “treatable but not curable” is oncologist-speak that means exactly that: Mrs. Edwards’ breast cancer is now stage IV, and stage IV breast cancer is not curable. She will die either of or with her disease, much more likely the former. The only question is how much time she has left. Her tumor is, however, eminently treatable, and her survival can be prolonged and quality of life improved by various therapies.
Bone happens to be one of the most common organs to which breast cancer metastasizes, the others being liver, lung, and brain. How much time Mrs. Edwards has left depends a lot on what her true presentation is. Not all stage IV breast cancer is created equal. For example, isolated bone metastases, with no disease anywhere else, tend to have an indolent course compared to other stage IV disease. The five year survival for all comers with metastatic breast cancer is in the 20% range, with a median survival of around 16-24 months. However, for isolated, low volume bone disease, which is what Mrs. Edwards appears to have, the prognosis, while still grim in the long term, is usually better than that. For such patients, I’ve seen a couple of series with median survivals as high as 48 months reported, although that’s at the high end. Probably a reasonable expectation for a single isolated small skeletal metastasis is for a five-year survival rate of around 30-40%, maybe even slightly better than that. Prognosis also depends upon the disease-free interval between conclusion of her primary treatment and recurrence. Rapid recurrence portends a worse prognosis. Since Mrs. Edwards was diagnosed in late 2004, her disease-free interval is on the order of two years, which is fairly typical and probably doesn’t suggest an unusually virulent tumor. (Unfortunately, it’s virulent enough.) In any case, we don’t know enough to determine for sure whether Mrs. Edwards will have the better prognosis of a patient with isolated bone metastasis or the worse prognosis of a woman with metastases to other organs, because it has been reported that she had abnormalities in her lung as well that were too small to characterize but sound mildly suspicious. If these turn out to be lung metastases, then Mrs. Edwards’ prognosis is likely to be considerably worse than if her rib is the only site of disease.
It should also be remembered through this, however, that metastatic breast cancer has a long “tail” on its survival curve. The numbers above are medians and averages. There are some patients who lives several years with metastatic disease, sometimes even considerably longer than 10 years. (One also has to remember that, because the above are medians, half will do worse than the estimates.) A very few even approach 20 years, but this is rare. These women, of course, are a small minority, but there does definitely appear to be a definable subset of women with less aggressive, more indolent disease who can do surprisingly well for a surprisingly long time. Their disease never goes away, but they seem to do alright.
The treatment of metastatic breast cancer is palliative in nature. It used to be fairly nihilistic 20-30 years ago, when expected survival was shorter, but now that more recent treatments have significantly increased expected survival times, how metastatic breast cancer is treated is evolving. First, local treatment usually consists of radiation therapy if the bone metastasis is causing pain. Systemic therapy usually consists of estrogen-blocking drugs. However, this would depend on whether or not Mrs. Edwards was already taking Tamoxifen at the time she recurred. She likely would have been if her original tumor were estrogen receptor-positive because the usual course of Tamoxifen is 5 years. Obviously, if the tumor grew while she was on Tamoxifen, that would be of concern. Newer estrogen blocking drugs, such as the aromatase inhibitors, are also a consideration and indeed appear to be supplanting Tamoxifen in many ways in the treatment of breast cancer. Other drugs that are often used are biphosphonates to lessen the likelihood of pathological fractures due to tumor. Chemotherapy is usually reserved as the last line, for when other modalities have failed or when rapid palliation is needed for pain or other symptoms caused by tumors impinging on nerves or other structures.
In the end, as for all patients, it’s impossible to predict how long Mrs. Edwards has, especially since she has breast cancer. We can cite median survivals and expected five year survival percentages all day, but breast cancer tends to be so variable that making anything other than the vaguest prediction is fraught with uncertainty. It is quite difficult to extrapolate population data to any single patient in making such predictions. I’m hoping that she’s one of the small subset of women who manage to do quite well and lives another decade or more. Even if she is, what we can predict, assuming that she has bone metastases only, is that, sadly, were Edwards to succeed in his Presidential bid, it would be more likely than not that Mrs. Edwards would not make it through his first term, and it would be highly unlikely that she would survive through a second Edwards term. I hate to be so blunt about it, but that’s the reality of her situation, and the situation would be considerably more bleak if she does turn out to have lung metastases, where her estimated survival would be in the range of 18-36 months. Be that as it may, if she does have indolent disease, campaigning over the next 10 months or so until the Democratic primaries is unlikely to cause her harm and may even help her maintain the positive mental attitude that she will need to handle the medical trials that are to come. After that, there’s a decent, but not as good, chance that she will continue to do well through a general election campaign, if it were to come to that. After that, it becomes very hard to predict, and there is always the sad possibility to be considered that Mrs. Edwards may turn out not to be one of the fortunate ones who do well and live a long time with this disease.
Here’s hoping that’s not the case.
ADDENDUM: The Cheerful Oncologist has more, explaining the factors that need to be taken into consideration to decide on what treatment she needs and make estimates about her prognosis. His explanations of the variables involved should help you understand that, when we as doctors waffle about making predictions, it’s not because we’re dissembling. It’s because there’s so much variability among patients in this disease.
