I can’t decide whether it is harder to blog about the San Antonio Breast Cancer Meeting when I am there or when I am not. When I am there in the midst of the crowd (actually I usually sit way over at one side near a plug for my laptop), I take things in but do not have a lot of time to think about them. Some findings which are only iterative are presented as if they are big news and others that really set the stage for big changes in practice are treated as old news. When I’m reading the tweets, posts and press releases from home, I have more time to think but less access to the buzz. Nonetheless I promised you summaries, so here goes.
Screening
The mammography screening talks have gotten some attention but really are not anything new. Gilbert Welch gave a talk suggesting that screening with mammography should be a choice and not a public health issue. He reiterated that the problem with mammography is that the biology of the tumor trumps the notion of early detection. Regardless of the improvements in mammography, the number of deaths from breast cancer has remained about the same. In fact, Welch argued that with better treatments we are seeing less impact of mammography on the outcome. He particularly pointed out the problem with false positives or things that appear on the mammogram as potentially being malignant but turn out not to be. Even more of a problem, according to Welch, are the cancers that are being diagnosed that may never have progressed if left alone; e.g., the dormant tumors and/or DCIS lesions. This is a problem because of the collateral damage of treatments that might not be necessary. He suggests that screening should be the woman’s choice and that we should not be using the number of women screened as a quality metric for health care systems.
The second mammography talk was by Robert Smith of the American Cancer Society. While Welch is well known for questioning mammography, Smith is well known for championing it. His study, however, was pretty predictable. All of the studies used different parameters; i.e., age, frequency of mammograms, and follow up. He found that you could take all of the mammography screening studies and re-jigger them so that they were all comparable and that the benefit demonstrated was about the same. My only complaint with the study and even more with the press surrounding it is that the study only referred to mammography in women over 50. This is a group where most everyone agrees there is a benefit, if small. Yet the press does not make this distinction, potentially misleading people to think that screening in women under 50 is generally considered beneficial when in fact, it is not!
HER-2 neu
The general session appeared to be focused on HER-2 positive cancers. In the first study, NeoAllto compared taxol and herceptin to taxol, herceptin and lapatinab given to women before the tumors were removed. The number of tumors that completely disappeared with the treatments was about the same in both groups but the side effects were worse when lapatinab was added. While there was some anticipation that data would show whether pathological response (i.e., the tumor completely disappearing when systemic therapy was given prior to surgery) predicted overall survival, this was not discussed in the meeting, as far as I can tell. We will have to wait for that. The reason we care is that more and more neoadjuvant systemic therapy (i.e., giving systemic therapy after the core biopsy but before surgery) is being used with the hope it can predict whether the systemic therapy is also working elsewhere in the body where it may be harder to measure. This question remains open.
A second study looked at whether adding Avastin (bevacizamab) to a chemo and herceptin treatment regime added anything. In fact, it did not. Nor did adding adriamycin (i.e., an anthracycline) to the chemo provide additional benefit.
On the other side was an intriguing study looking at tumor associated lymphocytes (TILs) or a type of white blood cells that are sometimes associated with cancers. We know that some immune reaction can be good at controlling cancer while others can aggravate it. This is a hot area of research as many groups are looking to see how we can channel the immune system to help control cancers. In this particular study, the TILs predicted which HER-2 positive cancers would benefit the most from herceptin. In order for a tumor to grow, it has to suppress the immune system. This research suggests that herceptin relieves the tumor-induced immunosuppression and thus allows the immune system to work with herceptin in defeating the cancer. This is very interesting as it sheds new light on the complexity of tumors and the multiple factors that we can manipulate to increase survival.
Metastatic Disease
A very interesting series of studies from Turkey and India looked at whether doing surgery on the primary breast tumor in women with metastatic disease gives any survival advantage. These two studies suggest that primary surgery does not have any impact and as a result, the recommendation is to only do surgery if it will improve the quality of the woman’s life; i.e., the cancer is ulcerated and bleeding or infected. There are currently several other studies going on in an attempt to answer this question. While it remains unanswered with no evidence that there is a benefit in these two studies, it is unlikely that there is any major effect.
In a day full of HER-2, there is one important truth. When I started taking care of women with breast cancer, HER-2 neu overexpression was a predictor for a poor outcome. Now with years of research starting with Dennis Slamon at UCLA, we not only understand this type of breast cancer better but the outcomes are significantly better. That is a real and tangible benefit of research!
