VAREN BLACK: Doctor, what about nodal involvement?
WILLIAM GRADISHAR, MD: Nodal involvement's one of the critical -- in a sense -- demarcation points between low- and high-risk. If you look at all patients who are lymph-node negative, the majority of those patients are cured of their disease by local therapy alone -- meaning mastectomy or lumpectomy plus radiation therapy.
On the other hand, once lymph nodes are involved under the arm, it implies -- by definition -- that the tumor has already gone from the breast into the lymph nodes, demonstrating an ability to spread. So as the number of lymph nodes increases from one to three to five to ten, the tumor burden increases, and the probability that there could be disease somewhere else in the body increases. So those are women with positive lymph nodes and more of them as they accumulate more lymph nodes, the risk of recurrence is elevated as well.
VAREN BLACK: Why does adjuvant therapy involve a combination of several drugs?
WILLIAM GRADISHAR, MD: The adjuvant therapy approach that we use has been arrived at through a process of clinical trials. And in the earliest days of adjuvant therapy, single drugs were administered, and then as more drugs became available -- that is, anti-cancer drugs -- we looked at combining them. And what was determined from that process was that combinations of drugs that did not behave in exactly the same way against the cancer cell had an advantage.