What Kind of Lumps Are Normal in Breasts?


In fact, most breast lumps are not cancer. Researchers estimate that between 60 and 80 percent of breast lumps are actually benign, or noncancerous. Lumps can occur for many reasons. Read on for more information about these causes and what a breast lump may mean.

When you find a breast lump, it can be terrifying. But breast tissue can change with things like nursing and hormones, and a lump doesn’t necessarily mean it’s cancer.

Breast lumps in women can happen for a variety of reasons and are not always cancerous. Knowing the different kinds of breast lumps can help you understand your medical reports and help ease your mind.


A breast cyst is a fluid-filled sac. They often happen in women who are nearing menopause. You might notice them getting bigger and more tender right before your period, and they can form very quickly. They are typically noncancerous and may be caused by blocked breast glands. They may feel soft or hard.


A breast abscess is a pocket of pus from an infection. It creates a sore lump in your breast, as well as inflammation. It can also cause fever, fatigue, and nipple draining. You’ll need an examination, and it may be necessary to drain the pus.

Fat necrosis

Johns Hopkins Medicine says that fat necrosis may form round and hard lumps in your breast. They are generally painless and caused by damaged and disintegrating fatty tissues. These types of lumps often occur in women with larger breasts, after a blow to their breasts, or following radiation for breast cancer. These are not cancerous and do not increase your chances of developing cancer.


Fibroadenomas are benign tumors in your breast. Some are very small and you can’t feel them, but you can feel others. They’re generally well-defined, moveable, and not tender or sore. The exact cause of these tumors is unknown, but it’s thought to be related to hormones. The American Society of Breast Surgeons Foundation says that these lumps are very common, occurring in about 10 percent of women in the United States.


Johns Hopkins Medicine says that a galactocele is also called a milk retention cyst. These lumps are fluid-filled and caused by a blocked milk duct. They are usually found in women who are or who have recently stopped lactating.


According to Breastcancer.org, a hematoma is a collection of partially clotted or clotted blood outside a blood vessel. It may be caused by trauma or injury. These lumps may develop a week to 10 days after surgery. They feel swollen, and you might be able to feel the fluid inside the lump moving around.

Sclerosing adenosis

According to the American Cancer Society, adenosis is a benign condition in which milk-producing glands in your breast, called lobules, are enlarged, and there are extra lobules present.

In sclerosing adenosis, the enlarged lobules become misshaped because of scar-like tissue. Your breast may be painful. Because these lumps can sometimes feel like cancerous lumps, you may have a biopsy to rule out cancer and get a more accurate diagnosis. These lumps usually don’t require treatment.

News Bureau


CHAMPAIGN, Ill. — A new approach to treating breast cancer kills 95-100% of cancer cells in mouse models of human estrogen-receptor-positive breast cancers and their metastases in bone, brain, liver and lungs. The newly developed drug, called ErSO, quickly shrinks even large tumors to undetectable levels.

Led by scientists at the University of Illinois Urbana-Champaign, the research team reports the findings in the journal Science Translational Medicine.

“Even when a few breast cancer cells do survive, enabling tumors to regrow over several months, the tumors that regrow remain completely sensitive to retreatment with ErSO,” said U. of I. biochemistry professor David Shapiro, who led the research with Illinois chemistry professor Paul Hergenrother. “It is striking that ErSO caused the rapid destruction of most lung, bone and liver metastases and dramatic shrinkage of brain metastases, since tumors that have spread to other sites in the body are responsible for most breast cancer deaths,” Shapiro said. (Watch a video about the results.)

Illinois researchers on the study include, from front left, research scientist Chengjian Mao and graduate students Matthew Boudreau, Darjan Duraki and Ji Eun Kim. In the back row, from left, are molecular and integrative physiology professor Erik Nelson, chemistry professor Paul Hergenrother and biochemistry professor David Shapiro. Photo by L. Brian Stauffer Delete Edit embedded media in the Files Tab and re-insert as needed.

The activity of ErSO depends on a protein called the estrogen receptor, which is present in a high percentage of breast tumors. When ErSO binds to the estrogen receptor, it upregulates a cellular pathway that prepares cancer cells for rapid growth and protects them from stress. This pathway, called the anticipatory Unfolded Protein Response, or a-UPR, spurs the production of proteins that protect the cell from harm.

“The a-UPR is already on, but running at a low level, in many breast cancer cells,” Shapiro said. “It turns out that this pathway shields cancer cells from being killed off by anti-cancer drugs.”

Shapiro and former U. of I. medical scholar Neal Andruska first identified the a-UPR pathway in 2014 and reported the development of a compound that pushed the a-UPR pathway into overdrive to selectively kill estrogen-receptor-containing breast cancer cells.

“Because this pathway is already on in cancer cells, it’s easy for us to overactivate it, to switch the breast cancer cells into lethal mode,” said graduate student Darjan Duraki, who shares first-author status on the new report with graduate student Matthew Boudreau.

While the original compound prevented breast cancer cells from growing, it did not rapidly kill them, and it had undesirable side effects. For the new research, Shapiro and Hergenrother worked together on a search for a much more potent small molecule that would target the a-UPR. Their analysis led to the discovery of ErSO, a small molecule that had powerful anticancer properties without detectable side effects in mice, further tests revealed.

“This anticipatory UPR is estrogen-receptor dependent,” Hergenrother said. “The unique thing about this compound is that it doesn’t touch cells that lack the estrogen receptor, and it doesn’t affect healthy cells – whether or not they have an estrogen receptor. But it’s super-potent against estrogen-receptor-positive cancer cells.”

ErSO is nothing like the drugs that are commonly used to treat estrogen-responsive cancers, Shapiro said.

“This is not another version of tamoxifen or fulvestrant, which are therapeutically used to block estrogen signaling in breast cancer,” he said. Even though it binds to the same receptor that estrogen binds, it targets a different site on the estrogen receptor and attacks a protective cellular pathway that is already turned on in cancer cells, he said.

“Since about 75% of breast cancers are estrogen-receptor positive, ErSO has potential against the most common form of breast cancer,” Boudreau said. “The amount of estrogen receptor needed for ErSO to target a breast cancer is very low, so ErSO may also work against some breast cancers not traditionally considered to be ER-positive.”

Further studies in mice showed that exposure to the drug had no effect on their reproductive development. And the compound was well tolerated in mice, rats and dogs given doses much higher than required for therapeutic efficacy, the researchers found.

ErSO also worked quickly, even against advanced, human-derived breast cancer tumors in mice, the researchers report. Often within a week of exposure to ErSO, advanced human-derived breast cancers in mice shrank to undetectable levels.

“Many of these breast cancers shrink by more than 99% in just three days,” Shapiro said. “ErSO is fast-acting and its effects on breast cancers in mice are large and dramatic.”

The pharmaceutical company Bayer AG has licensed the new drug and will explore its potential for further study in human clinical trials targeting estrogen-receptor-positive breast cancers, the researchers said. The researchers will next explore whether ErSO is effective against other types of cancers that contain estrogen receptor.

Study co-authors at the U. of I. also include veterinary clinical medicine professor Timothy Fan, molecular and integrative physiology professor Erik Nelson, and professor emeritus of pathology Edward Roy. Fan, Hergenrother, Nelson, Shapiro and Roy are affiliates of the Cancer Center at Illinois. Fan, Hergenrother and Nelson also are affiliated with the Carl R. Woese Institute for Genomic Biology at Illinois and Hergenrother and Fan are faculty in the Carle Illinois College of Medicine at the U. of I.

Funders of this work include the University of Illinois, the U.S. Department of Defense, the National Institutes of Health, and Systems Oncology. The U. of I. has filed patents on some compounds described in the study.

Hundreds of chemicals found in common household items may cause breast cancer


NEWTON, Mass. — Nearly 300 toxic chemicals may be lurking in common items in your home right now, a new study warns. Researchers from the Silent Spring Institute in Massachusetts say exposure to these chemicals may increase a person’s risk of developing breast cancer.

The study finds these products include everything from processed foods, to lipstick and mascara, pesticides, and even furniture. The ingredients, called endocrine disrupting inhibitors, fuel hormones that trigger the disease.

“The connection between estrogen and progesterone and breast cancer is well established,” says co-author Dr. Ruthann Rudel, an toxicologist at Silent Spring Institute, in a media release.

“So, we should be extremely cautious about chemicals in products that increase levels of these hormones in the body.”

Every day, people encounter a variety of synthetic chemicals through the products they use or the food they eat. The team notes that such chemicals also make their way into contaminated drinking water. For many of these toxins, their impact on human health is still unknown.

How are these chemicals affecting breast tissue?

The new study reveals that these chemicals make cells in breast tissue produce more estrogen or progesterone. The study in Environmental Health Perspectives combed through data on more than 2,000 chemicals examined by the U.S. Environmental Protection Agency (EPA)’s ToxCast program.

In laboratory experiments on cells, 296 raised levels of progesterone or estradiol, a form of estrogen. Over 70 percent of these substances increased both. Researchers find many of the chemicals are in additives in processed foods, such as packaged meat, pies, sweets, and snack foods.

Personal hair care products such as hair dye also make the list, along with other consumer goods. Study authors warn that appliances include harmful flame retardants in their building materials, which can leak out into the environment.

Almost two decades ago, the Women’s Health Initiative study discovered a link between hormone replacement therapy and breast cancer. Women stopped taking the drugs and cases went down.

“Not surprisingly, one of the most common therapies for treating breast cancer is a class of drugs called aromatase inhibitors that lower levels of estrogen in the body, depriving breast cancer cells of the hormones they need to grow,” Dr. Rudel adds.

A wake up call for the manufacturing industry?

The researchers don’t yet know how the chemicals are causing cells to produce more hormones. The may be acting as aromatase activators, for instance, which would lead to higher levels of estrogen.

“What we do know is that women are exposed to multiple chemicals from multiple sources on a daily basis, and that these exposures add up,” explains co-author Dr. Bethsaida Cardona.

The goal of ToxCast is to improve the ability of scientists to predict whether a chemical will be harmful or not. It uses automated chemical screening technologies to expose living cells to chemicals and then examine the different biological changes they cause. The researchers hope the study will be a wake up call for regulators and manufacturers.

The team notes that current safety tests in animals fail to look at changes in hormone levels in mammary glands in response to chemical exposure. These tests also don’t use high throughput testing in cells to identify chemicals that trigger estrogen or progesterone.

“This study shows that a number of chemicals currently in use have the ability to manipulate hormones known to adversely affect breast cancer risk,” says study editor Dr. Sue Fenton, a breast health expert at the National Institute of Environmental Health Sciences.

“Especially concerning is the number of chemicals that alter progesterone, the potential bad actor in hormone replacement therapy. Chemicals that elevate progesterone levels in the breast should be minimized.”

Protecting children from harmful toxins

The study authors are calling for improvements in testing to help identify potential breast carcinogens before they end up in products. They also suggest finding ways to reduce people’s exposures, particularly during critical periods of development. This includes puberty and pregnancy, when the breast undergoes important changes.

The project is part of Silent Spring’s Safer Chemicals Program which is developing new cost-effective ways of screening toxins’ effects on the breast. The knowledge will help government agencies regulate chemicals more effectively and assist companies in developing safer products.

The American Cancer Society estimates that 281,550 women will receive a breast cancer diagnosis this year. Experts say over 43,000 Americans will die from the disease in 2021.

SWNS writer Mark Waghorn contributed to this report.