Some patient advocates drew my attention to a paper published in a prestigious journal, Nature Reviews Cancer. The article indicates that between 2005 and 2015, there was no improvement in survival among women with metastatic breast cancer. The advocates, who live with that condition, were particularly concerned about a graph suggesting that 5-year survival dropped a tad, from around 26% to 25%, in that decade. “Can we talk about this?” Beth Caldwell, co-founder of METUP, tweeted.
The article, by Dr. Patricia Steeg of the National Cancer Institute (NCI) also calls out an “alarming” but debatable decline in survival in other advanced cancers, including ovarian, prostate and uterine tumors, and a general lack of progress against metastatic disease. For now, I’ll focus on breast cancer. The apparent decline was not statistically significant, an NCI spokesperson later confirmed (see below).
To clarify the facts, I contacted Dr. Angela Mariotto of the NCI’s Cancer Surveillance Research Program. And while the statistics update is far from terrific, it’s slightly reassuring that the numbers have been heading in the right direction. Here’s the information her group provided, conveyed by an NCI spokesperson:
- From 2000 through 2010, median survival for U.S. women with metastatic breast cancer increased from 22 to 30 months.
- From 2000 through 2010, the 5-year relative survival for women with metastatic breast cancer rose, from 25.9% to 32.6%, This increase was statistically significant (confidence intervals: 24.9 - 27.0%, and 31.6 - 33.6%, respectively).
Median survival (left) and 5-year relative survival (right) after an initial diagnosis of metastatic... [+]
What this means, first, is that in the five years before 2000, half of women with stage 4 breast cancer lived for 22 months or longer; by 2010, half lived 30 months or longer. These findings are based on data in a public database (SEER 11), collected in the periods 1995-2000 and 2004-2010, respectively. As explained in a handy SEER glossary, “relative” 5-year survival indicates how long the cancer patients live compared to age and sex-matched controls in the population.
Unfortunately, at this time there is insufficient information available to estimate survival for men with stage 4 breast cancer. These findings apply predominantly to women who were first diagnosed, de novo, with metastatic breast cancer.
The low numbers might upset someone who is not aware of the fact that–despite so much progress against early-stage, local and “regional” breast cancers–metastatic breast cancer remains incurable. That most women with metastatic disease die within three years of diagnosis, still, or at least until 2010, is a very sad statistic.
On the bright side: Survival has gone up, and measurable progress was evident by 2010. I’d go as far to say that most likely, and almost certainly, survival continued to improve from 2010 and 2015. If you consider all the new drugs that have come out since 2010, particularly for estrogen-positive, hormone-sensitive breast cancer, the most frequent forms, and for Her2 positive cases, for which there are, now, quite a few helpful agents (there were none in 2000), and better diagnostic testing for tumor subtypes, that these medications can be prescribed sensibly, the outlook should be better now, in 2016. And by 2020, who knows?
So things are looking up, but from a pretty dark place.
That said, these statistics are not OK. They’re not even close to OK. These disturbingly low figures support the Metastatic Breast Cancer Network’s mantra: “Stage 4 Needs More,” and, more generally, the need for increased research, rapid drug development and better oncology care (including full access to trials and modern care) for people living with metastatic cancer. Breast cancer causes over 40,000 deaths every year, in the United States. Advocate Shirley Mertz has likened the situation to an airplane’s worth of lives lost, each day. Over half a million die from breast cancer globally. (No one counts.)
According to the NCI’s SEER Stat Fact Sheet on Female Breast Cancer, accessed today (May 13, 2016), relative 5-year survival of women with “distant” breast cancer, i.e. with stage 4, metastatic disease, is 26.3%.
Dr. Steeg declined to respond to questions for this article. An NCI spokesperson referred me to the two papers she cites to support the graph at issue (Figure 1C) in her Nature Reviews paper. Those reports, Cancer Statistics, 2005 and Cancer Statistics, 2015, were prepared and published by the
An NCI spokesperson suggested possible explanations for the differences between the positive SEER findings from the NCI Cancer Surveillance Group (above), and the graph in the Nature Reviews paper. The main reason is that two papers cited by Steeg pull information from distinct SEER databases, which include distinct data registries and sets of linked registries.
So it might be that the issue arose upon comparing apples and oranges or, more accurately, comparing women with stage 4 cancer in one population, for which there is a database, and women with stage 4 cancer in another population, for which there is another database.
This article was delayed, and also prompted in part, by the fact that two different research groups within the NCI were reporting different numbers and trends for the same subject. Last October, I had multiple conversations with Dr. Mariotto at the NCI, and she had provided data showing a clear and upward trend in survival with metastatic breast cancer, between 1975 and 2011, reported here. Knowing that, I was puzzled when I saw the graph in Nature Reviews Cancer.
I kept wondering: How can researchers at the same institution provide such distinct facts? And consider that these are numerical, nominally non-subjective facts, what should be straightforward. What if the researchers were assessing subjective symptoms, or measuring quality-of-life issues? Need this be so complicated?
On the other hand, careless use of statistics can generate misinformation, and mislead patients. For that reason, I think the work that the NCI epidemiologists and math-PhD number crunchers is crucial. But it needs be done faster, and followed by much more rapid publication of the findings.
The public has every right to current information, on what’s known about survival after a diagnosis of metastatic breast cancer, and for all forms of cancer. Conveying information that’s bleaker than the reality, whether it comes from a doctor or a journalist or a scientist, can unduly dishearten patients. If there is measurable progress, however slight, that story should be carefully told.
