Table of ContentsView AllTable of ContentsDifferencesMammogramsUltrasoundMRIsBiopsyFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
Differences
Mammograms
Ultrasound
MRIs
Biopsy
Frequently Asked Questions
Finding a lump in the breast may spur the question: What does a tumor look like? A tumor, another name for a breast lump, mass, nodule, growth, or swelling, will look and feel differently depending on whether it is benign (noncancerous) or malignant (cancerous).
Breast changes over the course of a woman’s life are common. And most breast lumps turn out to be benign.Benign growths feel soft or squishy and may move freely. A malignant tumor may feel firm and may not move around. Breast lumps are only due tobreast cancersometimes.
This article will help explain the differences between noncancerous and cancerous tumors. It will help you to better understand what they feel and look like, how they are diagnosed, and what to do about them.
Verywell / Jessica Olah
How a Cancerous Tumor Differs From a Benign Mass
Signs of Cancerous Masses
On exam, other changes may be present as well. These changes may include:
One type of breast cancer,inflammatory breast cancer, does not usually cause a lump. Instead, you may see redness, swelling, and sometimes a rash on the skin of the breast.
Signs of Benign Breast Masses
In contrast to breast cancer tumors, benign lumps are often squishy. They may feel like a soft rubber ball with well-defined margins. They’re often easy to move around (mobile) and may be tender.
Infections in the breast can cause redness and swelling. Sometimes it can be difficult to tell the difference betweenmastitis(inflammation of breast tissue) and inflammatory breast cancer, but mastitis often causes symptoms of fever, chills, and body aches. Those symptoms aren’t associated with cancer.
Cysts andfibroadenomasare the two most common causes of benign breast masses. A cyst is a pocket filled with fluid. Cysts in female breast tissue are most common between the ages of 35 and 50 and just before menopause. They’re rarely cancerous.
A fibroadenoma is a smooth, solid, firm lump that is not cancerous. They often appear in female breast tissue in people who are in their 20s and 30s but can occur at any age. Fibroadenomas feel rubbery and are not painful.
Nipple Changes: What’s Normal and What’s Not
Appearance on a Mammogram
Cancerous and benign masses may appear similar on amammogram. However, some findings are more common in one than the other.
It’s important to note that around 20% of breast cancers don’t even show up on a screening mammogram.On the other hand, benign breast changes sometimes look like cancer.
Mass Due to Cancer
A breast cancer tumor on a mammogram is often irregular. The edges of the mass don’t look smooth. They also may appear jagged.
A spiculated breast mass, with spikes that extend out from the main mass, is a strong signal that suggests cancer.
Cancers often appear bright when looking at mammogram pictures. The area around the mass may be distorted.Breast calcifications(calcium deposits in the breast), especially when grouped in clusters, may be visible as well.
Mass Due to Benign Conditions
On a mammogram, benign tumors often appear round or oval (ellipsoid) with clear, well-defined edges.
ExceptionsBenign conditions such as breastadenosis(numerous and enlarged milk glands),fat necrosis(damage to fatty breast tissue), andradial scars(growths that look like scars when magnified) may look very similar to cancers on a mammogram.
Exceptions
Benign conditions such as breastadenosis(numerous and enlarged milk glands),fat necrosis(damage to fatty breast tissue), andradial scars(growths that look like scars when magnified) may look very similar to cancers on a mammogram.
Normal and Abnormal Mammogram Images
Appearance on an Ultrasound
Breast ultrasound can detect some lumps that a mammogram cannot. It is also used to help diagnose masses found on a mammogram.
Ultrasound can help tell the difference between fluid-filled cysts, which aren’t likely to be cancerous, and hard cysts that need further testing.
On an ultrasound report, the term “hypoechoic” refers to an area that appears darker in the images. This means the area is solid. Hard cysts have a higher chance of being malignant than cysts filled with fluid.
On ultrasound, a breast cancer tumor is often seen as hypoechoic. It has irregular borders and may appear spiculated. Other ultrasound findings that suggest breast cancer include:
With benign masses, a fluid-filled cyst may be noted. Solid benign masses usually:
Ultrasound for Breast Abnormalities
Appearance on an MRI
Abreast magnetic resonance imaging(MRI) scan can sometimes provide a clearer, more precise view than a mammogram to determine if a mass is cancerous or benign. That’s especially true in people who havedense breasts.
During a breast MRI, a contrast agent is injected into the bloodstream. When this contrast “lights up” a region on the image, the region is said to be enhanced.
Malignant Breast Tumor
Cancerous masses on MRI differ both in how they look and the length of time they appear (kinetics).Because a cancerous mass often has irregular or spiculated borders, the internal divisions will become enhanced. A brighter rim on the outside of the mass is also common.
Cancerous tumors also often have what’s called rapid signal intensity. This means they light up quickly from the contrast when the image is taken, but then wash out (dim) rapidly too.
Benign Breast Tumor
On an MRI, benign breast masses often have smooth borders or are lobulated. Any enhancement is usually minimal or patchy. The rise in signal intensity is slow, meaning the image becomes bright very slowly and it doesn’t wash out.
Appearance With a Biopsy
When abreast biopsyis done, tissue is removed and sent to apathologist. They will look at it under a microscope. Usually, special genetic studies are done as well.
Breast Cancer Tumor Cells
Under the microscope, breast cancer cells may appear similar to normal breast cells. They also may look quite different, depending on the tumor’s growth and grade.
Cancer cellsdiffer from normal cells in many ways. The cells may be arranged in clusters. They also may be seen invading blood vessels or lymphatic vessels.
The nucleus (center) of cancer cells can be striking, with nuclei that are larger and irregular in shape. These centers will stain darker with special dyes. Often, there are extra nuclei rather than just one center.
Benign Breast Mass Cells
Benign breast cells may or may not look identical to normal breast cells, depending on the type of mass, but neither do they look like cancer cells.
Cancer Cells vs. Normal Cells
Summary
Breast changes are common and most are not cancerous. Compared to benign lumps that tend to be soft and move around easily, breast cancer tumors may feel hard and immobile on a breast exam.
If you find a lump, contact your healthcare provider right away. Beyond a physical exam, the provider may use a mammogram, MRIs, and ultrasound to help with the diagnosis. A breast biopsy may be needed on the basis of these other findings. An early diagnosis is the best way to have a good outcome.
Cancerous breast tumors cannot be completely prevented, but maintaining a healthy lifestyle can lower your risk. Being physically active and eating a diet with lots of whole foods, like fresh fruits and vegetables, can reduce your risk of cancer.Getting recommended breast cancer screenings can help spot any cancers at an early, more treatable stage.
18 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.
World Health Organization.Breast cancer.
American Cancer Society.Breast cancer signs and symptoms.
American Cancer Society.Inflammatory breast cancer.
American Cancer Society.Fibrosis and simple cysts in the breast.
Johns Hopkins Medicine.Common benign lumps.
American Cancer Society.Limitations of mammograms.
Sturesdotter L, Sandsveden M, Johnson K, Larsson AM, Zackrisson S, Sartor H.Mammographic tumour appearance is related to clinicopathological factors and surrogate molecular breast cancer subtype.Sci Rep. 2020;10(1):20814. doi:10.1038/s41598-020-77053-7
American Cancer Society.Breast ultrasound.
Machida Y, Tozaki M, Shimauchi A, Yoshida T.Two distinct types of linear distribution in nonmass enhancement at breast MR imaging: Difference in positive predictive value between linear and branching patterns.Radiology. 2015;276(3):686-694. doi:10.1148/radiol.2015141775
Gao LY, Gu Y, Xu W, Tian JW, Yin LX, et al.Can Combined Screening of Ultrasound and Elastography Improve Breast Cancer Identification Compared with MRI in Women with Dense Breasts-a Multicenter Prospective Study. J Cancer. 2020 Apr 6;11(13):3903-3909. doi:10.7150/jca.43326
Shanmugasiva VV, Ramli Hamid MT, Fadzli F, et al.Myofibroblastoma of the breast.Malays J Pathol. 2018 Dec;40(3):349-353. PMID:30580368
American Cancer Society.Breast density and your mammogram report.
Jiang X, Xie F, Liu L, et al.Discrimination of malignant and benign breast masses using automatic segmentation and features extracted from dynamic contrast‑enhanced and diffusion‑weighted MRI.Oncology Letters. 2018;16(2):1521-1528. doi:10.3892/ol.2018.8805
Moffitt Cancer Center.Can a Benign Breast Lump Become Cancerous?
Centers for Disease Control and Prevention (CDC).Breast cancer basics.
Harvard T.H. Chan School of Public Health.High fruit and vegetable consumption may reduce risk of breast cancer, especially aggressive tumors.
National Cancer Institute.Physical activity and cancer.
Lehman C, Lee A, Lee C.Imaging management of palpable breast abnormalities.AJR American Journal of Roentgenology. 2014;203(5):1142-1153. doi:10.2214/ajr.14.12725
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