(NEW YORK) -- Sandra Bishnoi wasn't worried when she went to her gynecologist about some breast soreness in 2011. She was 37 and had just finished breastfeeding her new baby daughter, so Bishnoi, who has a PhD in chemistry, figured she was just experiencing one of the many bodily changes that come with pregnancy and new motherhood.
Bishnoi's gynecologist sent her to a nearby hospital for more testing that day, but Bishnoi never saw a breast cancer diagnosis coming.
"The light bulb never came off that it was serious," said Bishnoi, adding that she never thought to ask her husband to come with her to the doctor's office for support. "A surgeon actually came in to see me and said, 'We need to do a biopsy...Dr. Bishnoi, you can't leave this room without knowing you have breast cancer.'"
Doctors ultimately diagnosed Bishnoi with stage 4 inflammatory breast cancer that had metastasized to her bones.
Bishnoi was not only devastated, she was baffled. Wasn't breast cancer supposed to involve a lump? Wasn't she too young? Didn't she need a family history?
The short answer is that inflammatory breast cancer is different from other breast cancers. Since inflammatory breast cancer only accounts for between 1 percent and 5 percent of breast cancers, patients -- and some doctors -- often don't know what to look for.
"It's often not associated with a lump," said Dr. Mark Kelley, chief of surgical oncology and endocrine surgery at Vanderbilt-Ingram Cancer Center in Tennessee. (Kelley has never met Bishnoi.) "These patients just come in with red, swollen, possibly tender breasts."
It often looks more like an infection than cancer, so some doctors will prescribe antibiotics, giving the cancer more time to grow before it's caught, Kelley said.
An infection called mastitis is common in women who are breastfeeding and is to blame for breast swelling and discoloration most of the time, said Dr. Sandhya Pruthi, a breast cancer specialist and professor at the Mayo Clinic in Rochester, Minn. Doctors will often prescribe antibiotics for seven to 10 days to see what happens. If the symptoms don't go away, doctors should know it might be more than an infection and request more testing.
"You don't want to miss inflammatory breast cancer," Pruthi said. "Inflammatory breast cancer is uncommon and unfortunately it's not always a classic presentation. That's what makes it challenging. If you haven't seen it several times in your practice to know what you're looking for, you can miss it."
Even if a doctor suspects inflammatory breast cancer, it won't necessarily show up on a mammogram, Kelley said. It might show up on an ultrasound, but the best way to diagnose it is to do a skin biopsy. Unlike other breast cancers, inflammatory breast cancer starts in the milk ducts and spreads quickly via lymphatic vessels in the breast skin.
Bishnoi looked back and realized she actually had symptoms earlier but dismissed them. She remembered that her daughter didn't feed as well from the breast that had cancer, but she figured it was a clogged milk duct. She remembered that the same breast had some redness and dimpling but she thought it was thrush, which is also associated with breastfeeding.
It wasn't until Bishnoi stopped breastfeeding and realized that one breast hadn't returned to its normal size and firmness that she even considered going to a doctor.
"It was starting to cause me a lot of pain, but that's not normal for breast cancer either," Bishnoi said.
She never imagined that she had a rare breast cancer that spreads more easily than typical breast cancer and is harder to treat.
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