Node Negative and Micromets
This is a report from MedScape about the importance( or not) of chemotherapy for node negative women with micromets in an axillary node. Full disclosure: this was my situation with my first breast cancer in 1993, so I read it with particular interest. More full disclosure: at that time, I had surgery, radiation, chemotherapy, and hormonal therapy--in other words, everything.
This is an excellent example of how things change in the breast cancer world and how disconcerting that can be. In 1993, there was a strong bias towards treating a micromet like an any met and considering it a node positive situation. A few years later, a couple of studies came out that reinforced that position. Now, more than a decade later, we have another perspective. Although this most recent study from the NEJM does state that there is improved survival with more treatment, it concludes that the 1.2% better survival at five years is "small" and not worth pursuing. Personally, I feel pretty strongly that is a decision that is best left to an individual woman. For some women, that 1.2% may seem quite large--it would have to me at the time as I was a single parent with an 11 year old daughter at home.
Here is the introduction and then a link to read more:
In Node-Negative Breast Cancer, Micromets Not Worthy of Heavy Pursuit Nick Mulcahy
January 20, 2011 — Do micrometastases and isolated tumor cells affect the survival of women with breast cancer who initially have clinically negative axillary lymph nodes?
This is the question that investigators from the National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-32 have pursued in a study published January 19 in the New England Journal of Medicine.
It is an important question, in part because many surgeons and pathologists are currently seeking out these microscopic pieces of cancer with immunohistochemistry and other approaches that are beyond standard recommendations, one of the coauthors explained.
The standard approach, endorsed by the American Society of Clinical Oncology (ASCO), the American College of Surgeons(ACS), and other groups, is to slice sentinel nodes at 2.0-mm intervals and stain samples with hematoxylin and eosin.
The study found that "occult" metastases — that is, micrometastases and isolated tumor cells found after sentinel lymph node biopsy — are an independent prognostic variable in these women.
Women who had the micromets, as micrometastases and isolated tumor cells are collectively called, had statistically significantly worse overall and disease-free survival.
However — and this is a big however — the magnitude of the difference in overall survival at 5 years was "small" (1.2%) between the women with and without these occult micrometastases and isolated tumor cells, the study authors point out.
The upshot of the findings is that the extensive pursuit of tiny pieces of cancer in such patients is not worth the effort, they suggest.