Follow up to a question on breast cancer

I got a question about some of the ideas I was talking about in my last post on how I think about breast cancer. A breast cancer patient wrote me and asked about the difference in how her oncologist explains things
"They quote an 80% recurrence free 10 year survival rate for stage IIA and 75% for stage IIB. I'm stage IIA and my onc says I am probably cured (after surgery, chemo, etc.).

Do you really think all node positive younger women are destined to recur?

Another question: how do you compare positive nodes with lympho vascular invasion? My onc says that there is no data that LVI is as negative an indicator as nodes."

I think it's important to understand that not all breast cancers of stage "x" are created equal, and the biologic "aggressiveness" of a tumor can really skew your personal risks. I talked about 3 of the more important factors (node status, estrogen receptor status, and tumor size), but you've also got histologic characteristics (like tumor grade) and other genetic markers (like HER2/neu) in the mix. Some % of these patients also identified or unidentified inherited genes or mutations which increase their risk substantially for breast and other cancers.

There were two competing worldviews of breast cancer in the classic "Halsted Model" (breast cancer progresses from local->regional->systemic disease) and the "Systemic Model" (breast cancer is already systemic at the time of most diagnosis). I found a nice summary of these ideas on this old newsgroup post for those interested. Personally, I split the difference in my head in that I think that if you're node negative with favorable histology the Halsted model is still true, and that a true absence of residual cancer is possible. If you have nodes involved I'm inclined to believe the Systemic Model in that you have already likely have had some cancer burden establish elsewhere. This is supported by the fact that metastatic breast cancers still show up decades after mastectomy on occasion with no local or regional recurrence of the original cancer preceding it.

Younger breast cancer patients are particularly worrisome in that you have some many decades left of potential exposure for recurrence or new primary breast cancers. It makes absolutely no sense to me to push breast conservation (lumpectomy and radiation) for all but the most favorable invasive cancers in women in their 20's or early 30's. I think maximum risk reduction should be advised for many of these women with bilateral prophylactic mastectomy.

For stage II/III breast cancers (those without systemic mets) the data's a pretty slippery slope where 10 year survival curves run from 70-78% in the more favorable patients to 20-40% depending on grade, size, and # of nodes. This data is laid out nicely at this British Cancer site. Keep in mind that all 3 of those factors are subject to sampling error, and that some of the stage II patients are actually stage III.

There's a great article in the Atlantic magazine "Good News and Bad News About Breast Cancer" from a decade ago which is much more eloquent then I am trying to be reluctant about telling people they're "cured" from breast cancer. It features some of the work by one of my professors, the late Dr. John Spratt from the University of Louisville, who was really visionary in describing tumor's behavior and growth clinically

Breast cancer, unfortunately, is not among this select group (of tumors we can eradicate). As far as we know, a woman found to have invasive breast cancer is always at higher risk of dying prematurely than women without breast cancer. Even thirty years after her diagnosis she is up to sixteen times as likely to die of the disease as a woman in the general population. That is why responsible researchers in this field avoid the word "cure." Even as they report advances, they must acknowledge the reality: Postsurgical chemotherapy and antihormonal therapy do buy time—an important advance. The slowed progress of the disease can give a woman additional years of life and even allow her to die of other, less traumatic, causes. But breast cancer is every bit as incurable as it was in Halsted's day.



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