In recent years, bilateral mastectomy, as a surgical approach to prevent contralateral breast cancer, has gained a certain degree of attention and application. However, there is still controversy regarding the actual effectiveness of bilateral mastectomy in preventing breast cancer mortality. Recently, Dr. Steven Narod from the Dalla Lana School of Public Health published a research paper titled "Bilateral Mastectomy and Breast Cancer Mortality" in JAMA Oncology. "Oncology Frontier" specially invited Dr. Steven Narod to share his latest research findings, hoping to provide more thoughts and guidance for the prevention, diagnosis, and treatment of breast cancer.

Oncology Frontier：Your study indicates that although bilateral mastectomy significantly reduces the risk of contralateral breast cancer, it does not reduce breast cancer mortality. Does this mean that we need to reassess the clinical guidelines and patient counseling process for bilateral mastectomy?

Dr. Steven Narod：Certainly I think it impacts on the patient’s choice. The current guidelines do not recommend bilateral mastectomy for patients, a possible exception is for BRCA1 and BRCA2 mutation carriers. Women now get a bilateral mastectomy do so at their own choice. It’s very rarely recommended by the doctor. In fact, the doctor and the guidelines suggest not to do the bilateral mastectomy, and I think our study confirms that that’s a reasonable guideline. So it won’t change the guideline, but I think it will give the doctors and the patients more information about what’s behind the rationale for doing it by that on this tech to me, and what are the expected risks and benefits.

Oncology Frontier：In your study, were there specific patient subgroups, such as based on age, tumor characteristics, or genetic factors that responded significantly differently to bilateral mastectomy compared to the overall population?

Dr. Steven Narod：Overall we didn’t see an overall effect for the bilateral mastectomy. There was one exception though, the 15 percent or so of women with lobular breast cancer, which is a certain feature, a certain kind of breast cancer, did appear to have a slight improvement in survival with bilateral mastectomy. But for the most common kind of cancer, like ductal cancer, there was no difference, and for age groups and for race there was no difference.

Oncology Frontier：Considering the potential psychological and physiological impacts of bilateral mastectomy, did your study assess the impact of this surgery on patients’ long-term quality of life?

Dr. Steven Narod：Not in this study. This was a statistical study that we used data that was collected in the United States. However, my other research would confirm that those patients who choose to have the bilateral mastectomy, which is about 8 percent of all patients, or 20 percent of very young patients, who do have a bilateral mastectomy, do report an improved quality of life. And I think that makes sense because those who choose to have the bilateralistic technique usually do so because they’re unduly anxious or concerned about getting another breast cancer in the same breast and in the opposite breast. So for them, removing both breasts is reassuring that they won’t get another cancer. Our interviews with these patients have almost invariably shown that they’ve been very grateful for the opportunity to have the bilateral mastectomy and satisfied with the outcome, whether or not they had reconstructive surgery.Most of these patients will have their breasts best reconstructed, so it does give them a good body image and a sense of symmetry.

Oncology Frontier：What are the implications of your study’s findings for current breast cancer treatment strategies, particularly regarding the assessment of contralateral breast cancer risk and preventive measures?

Dr. Steven Narod：Well, I think there are clinical questions that we’ve gone into, but there’s also kind of a theoretical question about the nature of breast cancer, when it starts and how it spreads. We did find that women who got a contralateral breast cancer had a much higher chance of dying of breast cancer. The risk went up from like 13 percent to 30 percent. So getting a new breast cancer is a poor prognostic factor, but preventing it didn’t reduce the risk of dying, which leads me to conclude that this new breast cancer is not really capable of spread, but is a marker that there’s an underlying process going on.

This paper on the contralateral breast cancer is really one chapter in a series of studies we’ve done which come to the same conclusion, and it’s summarized recently in a book which I just published called “A Fair Trial: The Foundations of Breast Cancer,” which I think people would be interested in. (link: https://a.co/d/2I6YIlC)It covers all aspects of breast cancer: how it originates, how it spreads, and some of the paradoxes and contradictions that show up in this paper are dealt with further in that book.

The main paradox, I think, is if the contralateral cancer raises your chance of dying and preventing it should reduce your chance of dying, but we didn’t see that. It raises another question, of course, which is more intriguing and maybe more puzzling, which is if preventing the cancer doesn’t reduce your chance of dying, why would detecting it early through screening be more successful? So this book really challenges our conventional view of how breast cancer is detected in our early diagnosis, and maybe it’s time to re-examine some of the real fundamentals about what we think underlies the basis of breast cancer. I hope this helps clarify the findings of the study and its broader implications for breast cancer research and treatment.

Reference

1.     Giannakeas V, Lim D W, Narod S A. Bilateral Mastectomy and Breast Cancer Mortality[J]. JAMA oncology, 2024.

2.Narod S. A Fair Trial the Foundations of Breast Cancer. Gatekeeper Press. 2024 https://a.co/d/2I6YIlC