As part of treatment for breast cancer, surgical removal of the cancer is often required. To remove the tumor, two types of surgery may be done—a mastectomy, in which the entire breast is removed, or a lumpectomy, in which the tumor and some surrounding tissue are removed.
If you require alumpectomyfor breast cancer, your surgeon will remove the tumor and a border of normal tissue around it. This border is called the surgical margin. A pathologist will then examine this margin to determine if all the cancer cells in that area are gone.
If cancer cells are found anywhere between the tumor itself and the outer edge of the margin, additional surgery may be recommended. The goal of negative margins at surgery is to reduce the risk of breast cancer returning in that area, called a local recurrence.
This article will review the use of surgical margins in breast cancer treatment, and how surgical margins impact breast cancer surgery.
Verywell / Gary Ferster
Margin Sizes
To establish the width of a margin, the pathologist will measure the distance between the outer edge of cancer cells and the edge of the tissue that was removed. The tumor is usually “inked” on the edges. This allows the pathologist to clearly see the end of the tumor.
Surgical Margin Findings
A pathologist uses a special type of ink to draw a line along the outer edge of the entire tissue sample before slicing it into thin sections and examining it under a microscope.
The pathologist will use one of three terms to describe what they see:
FindingDefinitionNeed for Additional SurgeryNegative (clear) marginsNo cancer cells at the outer inked edge of the tissueNot typicalPositive (involved) marginsCancer cells or tumor extends to the edge of the sampleTypicalClose marginsAny situation in between negative and positivePossibleNext StepsA lumpectomy with clear margins may be the only surgery needed to treat breast cancer.Positive margins, on the other hand, may indicate that all of the cancer was not removed, and another surgery in the same area may be needed to remove more tissue.Close marginsfound after a lumpectomy might require another surgical procedure, called a re-excision. In this case, your surgeon would return to the original site and remove additional tissue to try to get negative margins.Amammogrammay be done to confirm that the entire tumor was removed and to determine if more tissue will need to be taken out.For women who’ve had a mastectomy, cancer cells in the margins within the breast usually have no effect on treatment decisions, since the whole breast was removed.In rare cases, however, cancer cells may be found close to the chest wall, possibly requiringmore surgery,radiation, and/orchemotherapy, depending on thestageand other features of cancer.Definition and Function of Lymph NodesSummaryDetermining surgical margins with breast cancer surgery is very important for the oncologist to know. The goal of removing the tumor is to reduce the risk of cancer returning in the future. Having negative, or clear margins can reduce the risk.Positive or close margins may require additional surgery for the surgeon to feel confident that all of the cancerous tissue was removed.A Word From VerywellOnce you’ve had a lumpectomy, you’ll find out if your surgical margins were negative, positive, or close.This, along withcancer type, stage, and lymph node status, will help you and your healthcare provider choose the most effective follow-up treatment for you.Read more about aphyllodes breast cancer tumor.Frequently Asked QuestionsGood margins are generally an area of healthy tissue after cancer has been removed. The exact size of the clear margin may depend upon the surgeon’s judgment.A positive margin means there are cancer cells at the edge of the tissue that was removed. This could mean that there are still cancer cells left in the body.A positive margin from a biopsy means that there could still be cancer cells in the body that were not fully removed during the biopsy.Clear margins in breast cancer mean that enough healthy tissue surrounding the cancerous tissue was removed during surgery. This is usually the goal of breast cancer surgery.
Next Steps
A lumpectomy with clear margins may be the only surgery needed to treat breast cancer.
Positive margins, on the other hand, may indicate that all of the cancer was not removed, and another surgery in the same area may be needed to remove more tissue.
Close marginsfound after a lumpectomy might require another surgical procedure, called a re-excision. In this case, your surgeon would return to the original site and remove additional tissue to try to get negative margins.
Amammogrammay be done to confirm that the entire tumor was removed and to determine if more tissue will need to be taken out.
For women who’ve had a mastectomy, cancer cells in the margins within the breast usually have no effect on treatment decisions, since the whole breast was removed.In rare cases, however, cancer cells may be found close to the chest wall, possibly requiringmore surgery,radiation, and/orchemotherapy, depending on thestageand other features of cancer.
Definition and Function of Lymph Nodes
Summary
Determining surgical margins with breast cancer surgery is very important for the oncologist to know. The goal of removing the tumor is to reduce the risk of cancer returning in the future. Having negative, or clear margins can reduce the risk.
Positive or close margins may require additional surgery for the surgeon to feel confident that all of the cancerous tissue was removed.
A Word From Verywell
Once you’ve had a lumpectomy, you’ll find out if your surgical margins were negative, positive, or close.This, along withcancer type, stage, and lymph node status, will help you and your healthcare provider choose the most effective follow-up treatment for you.
Read more about aphyllodes breast cancer tumor.
Frequently Asked QuestionsGood margins are generally an area of healthy tissue after cancer has been removed. The exact size of the clear margin may depend upon the surgeon’s judgment.A positive margin means there are cancer cells at the edge of the tissue that was removed. This could mean that there are still cancer cells left in the body.A positive margin from a biopsy means that there could still be cancer cells in the body that were not fully removed during the biopsy.Clear margins in breast cancer mean that enough healthy tissue surrounding the cancerous tissue was removed during surgery. This is usually the goal of breast cancer surgery.
Frequently Asked Questions
Good margins are generally an area of healthy tissue after cancer has been removed. The exact size of the clear margin may depend upon the surgeon’s judgment.
A positive margin means there are cancer cells at the edge of the tissue that was removed. This could mean that there are still cancer cells left in the body.
A positive margin from a biopsy means that there could still be cancer cells in the body that were not fully removed during the biopsy.
Clear margins in breast cancer mean that enough healthy tissue surrounding the cancerous tissue was removed during surgery. This is usually the goal of breast cancer surgery.
4 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Pilewskie M, Morrow M.Margins in breast cancer: How much is enough?Cancer. 2018;124(7):1335-1341.Morrow M, Van Zee KJ, Solin LJ, et al.Society of surgical oncology–American society for radiation oncology–American society of clinical oncology consensus guideline on margins for breast-conserving surgery with whole-breast irradiation in ductal carcinoma in situ.Practical Radiation Oncology. 2016;6(5):287-295. doi:10.1016/j.prro.2016.06.011BreastCancer.org.Lumpectomy surgery.American Cancer Society.MastectomyAdditional ReadingBarrio AV, Morrow M.Appropriate margin for lumpectomy excision of invasive breast cancer.Chinese Clinical Oncology. 2016;5(3):6-6. doi:10.21037/cco.v0i0.9764Breastcancer.org.Understanding your pathology report.
4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Pilewskie M, Morrow M.Margins in breast cancer: How much is enough?Cancer. 2018;124(7):1335-1341.Morrow M, Van Zee KJ, Solin LJ, et al.Society of surgical oncology–American society for radiation oncology–American society of clinical oncology consensus guideline on margins for breast-conserving surgery with whole-breast irradiation in ductal carcinoma in situ.Practical Radiation Oncology. 2016;6(5):287-295. doi:10.1016/j.prro.2016.06.011BreastCancer.org.Lumpectomy surgery.American Cancer Society.MastectomyAdditional ReadingBarrio AV, Morrow M.Appropriate margin for lumpectomy excision of invasive breast cancer.Chinese Clinical Oncology. 2016;5(3):6-6. doi:10.21037/cco.v0i0.9764Breastcancer.org.Understanding your pathology report.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Pilewskie M, Morrow M.Margins in breast cancer: How much is enough?Cancer. 2018;124(7):1335-1341.Morrow M, Van Zee KJ, Solin LJ, et al.Society of surgical oncology–American society for radiation oncology–American society of clinical oncology consensus guideline on margins for breast-conserving surgery with whole-breast irradiation in ductal carcinoma in situ.Practical Radiation Oncology. 2016;6(5):287-295. doi:10.1016/j.prro.2016.06.011BreastCancer.org.Lumpectomy surgery.American Cancer Society.Mastectomy
Pilewskie M, Morrow M.Margins in breast cancer: How much is enough?Cancer. 2018;124(7):1335-1341.
Morrow M, Van Zee KJ, Solin LJ, et al.Society of surgical oncology–American society for radiation oncology–American society of clinical oncology consensus guideline on margins for breast-conserving surgery with whole-breast irradiation in ductal carcinoma in situ.Practical Radiation Oncology. 2016;6(5):287-295. doi:10.1016/j.prro.2016.06.011
BreastCancer.org.Lumpectomy surgery.
American Cancer Society.Mastectomy
Barrio AV, Morrow M.Appropriate margin for lumpectomy excision of invasive breast cancer.Chinese Clinical Oncology. 2016;5(3):6-6. doi:10.21037/cco.v0i0.9764Breastcancer.org.Understanding your pathology report.
Barrio AV, Morrow M.Appropriate margin for lumpectomy excision of invasive breast cancer.Chinese Clinical Oncology. 2016;5(3):6-6. doi:10.21037/cco.v0i0.9764
Breastcancer.org.Understanding your pathology report.
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