After a diagnosis of cancer, a common initial response is, “Let’s get it out!” For women diagnosed with breast cancer who are eligible and choose to keep their breast, that standard surgery is called a lumpectomy or partial mastectomy. While the majority of patients require only a single lumpectomy on their breast, it’s not uncommon for 20-50% of patients to undergo a second cancer operation because “we didn’t get it all” with the initial surgery. Herein lies the controversy.
For decades, one of the most widely debated and reported topics in the treatment of breast cancer has been the status of surgical margins. In particular, many doctors continue to disagree about how wide of a rim of normal tissue around the cancerous lump in the breast needs to be removed. An article published yesterday in the NY Times online brings this question to the fore: http://www.nytimes.com/2012/02/01/health/repeat-breast-cancer-surgery-guidelines-found-unclear.html?_r=1&ref=health.
Most breast cancer experts agree that “no tumor on ink” is sufficient for surgical margins in patients who will receive postlumpectomy radiation therapy (RT). In other words, when the pathologist looks at the tumor specimen under the microscope, he or she should see no tumor cells touching the edge of the specimen that has been surgically removed from the breast. As breast surgical expert Dr. Monica Morrow from Memorial Sloan Kettering mentions in the article, ”there’s no evidence evidence that a margin any bigger than not touching ink affects cancer recurrence or survival.” However, some surgeons and radiation oncologists wrongly continue to insist upon a rim of normal tissue around the cancer of 2, 3 or even 5 millimeters. These doctors are subjecting their patients to additional surgeries which are largely unwarranted.
The status of surgical margins for breast cancer (and most other cancers) is merely an indication of the likelihood of microscopic tumor cells remaining locally in the body. In the case of breast conservation, the standard of care for most patients is postlumpectomy RT. In multiple major medical studies, RT has been proven to significantly decrease the risk of breast cancer returning locally which has led to improved overall survival. RT is highly effective at killing microscopic breast cancer cells in a local area or region of the body.
In conclusion, there is no clear evidence that patients who will be undergoing RT after lumpectomy require a second surgery if their surgical margins are negative (no tumor on ink). As Dr. Laurence McCahill, lead author of a recent major study published in the Journal of the American Medical Association (JAMA), explains in the NY Times article, “ this is a lot of second operations that maybe don’t make a difference.” For those with further interest, here’s the link to that manuscript: http://jama.ama-assn.org/content/307/5/467.full
- Patrick Maguire, MD