Is Breast Cancer Painful? What You Need to Know About This Less Common Symptom

There are many misconceptions around breast cancer, such as assuming that men cannot contract the disease or that wearing a bra can cause it. But one of the most widespread and potentially harmful myths is that breast cancer can't hurt.

This concept resurfaced late last week, after the former star Bachelorette party Katie Thurston has revealed that she has breast cancer. The 34-year-old shared in a Instagram story that she had noticed a lump in her breast, but waited to have it checked out by a doctor because it was painful. This pain "probably led to more doubt and a delay in screening, since most [websites] will say 'most breast cancers don't hurt,'" Thurston wrote. "I really thought it was PMS or exercise," she added.

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Unfortunately, doctors who treat breast cancer patients say this is a common misconception, which can lead to delayed diagnosis and treatment. Here's why and when breast cancer can hurt, and how to know when you should see a doctor for breast pain.

There are many reasons why breast cancer can be painful.

To be honest, yes, most women with undiagnosed breast cancer do not have pain. "It is not common for breast pain to be associated with breast cancer. However, it can still happen," Nicole Williams, MD, tells SELF, breast medical oncologist at The Ohio State University Comprehensive Cancer Center – James Cancer Hospital.

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But there are a handful of reasons why you might experience pain with breast cancer, and a lot of it comes down to the size of the tumor and its location, Richard J. Bleicher, MD, tells SELF, chief of the division of breast surgery at Fox Chase Cancer Center. "If you have a very large breast cancer, it can encroach on nerve structures, muscle structures, bone structures, and any component of the breast outside of the breast tissue, which can cause pain," he says.

But even small tumors can cause pain. “Breast cancers tend to be very hard,” says Dr. Bleicher. “Even if a lesion is small, it will cause discomfort if it touches a nerve or muscle.”

Some types of breast cancer are also more likely to be uncomfortable than others, explains Dr. Jason Mouabbi to SELF, assistant professor in the Department of Breast Medical Oncology at the University of Texas MD Anderson Cancer Center. Inflammatory breast cancer, which accounts for up to 5% of all breast cancers, typically causes symptoms such as redness, swelling, and severe breast pain, he points out. “But all breast cancers have the potential to cause pain,” says Dr. Mouabbi.

The myth that breast pain cannot be a sign of cancer is persistent.

The assumption that breast cancer won't hurt is "relatively accurate," says Dr. Bleicher. Most of the time, breast pain won't be due to breast cancer, Katherine Cline, CNP, tells SELF, breast cancer nurse practitioner at The Ohio State University Comprehensive Cancer Center – James Cancer Hospital. There are many other likely reasons why your breasts might be painful. “Breast pain is primarily caused by hormonal changes, certain medications, benign cysts/lumps, or infections,” Cline explains. Given that breast cancer is also painless most of the time, it’s easy to understand how people might completely dismiss it as a potential explanation for this symptom.