Bindi Irwin Announced She Had a 'Chocolate Cyst' Removed—Here's What That Means

Endometriosis specialists share what Bindi Irwin's diagnosis actually means.

Reality TV star Bindi Irwin recently revealed she had surgery to remove a type of cyst that can happen as a result of a common (and sometimes debilitating) condition that affects millions of women.

The Australian zookeeper and reality star—she appeared as a child on TV shows such as The Crocodile Hunter and later Crikey! It's the Irwins—disclosed in social media posts that she had been diagnosed with and treated for endometriosis, a condition in which tissue similar to that found in the lining of the uterus develops and grows in other parts of the body. Irwin also thanked fans for the support she has received during this medical journey.

Irwin specifically mentioned being treated for a growth that’s commonly referred to as a “chocolate cyst.” We asked doctors to explain what that is, why it happens and how it’s treated.

Related: Bindi Irwin Shares Video Celebrating Dad Steve Irwin: 'The Greatest Wildlife Warrior'

What Is Endometriosis?

Dr. Iris Kerin Orbuch, MD, endometriosis specialist, co-author of Beating Endo, and subject matter expert in the endometriosis documentary, Below The Belt, says endometriosis is a condition in which tissue similar to that found in the uterine lining (called the endometrium) develops and grows in other parts of the body. Although these growths often occur in the pelvic region, they can develop in or around organs elsewhere in the body. Pain, pressure, and other symptoms happen when this tissue grows or interferes with other bodily functions.

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What Is a Chocolate Cyst?

A lesion that develops as a result of endometriosis is known as an endometrioma. A chocolate cyst is a kind of blood-filled endometrioma found in the ovary. “Chocolate cysts of the ovary are named after the dark chocolate appearance of old blood that is trapped within them,” says Dan Martin, MD, Scientific and Medical Director at Endometriosis Foundation of America (EndoFound). By contrast, simple ovarian cysts typically contain clear fluid.

One type of chocolate cyst tends to grow larger over time. “With every menstruation, the endometriosis cells that are implanted bleed into the cyst, and the cyst slowly grows,” says Dr. Erkan Buyuk, MD, Board Certified OBGYN/REI at RMA of New York. “The blood gets digested over time, leading to a melted chocolate appearance. It is very specific to endometriosis.”

Are Chocolate Cysts Dangerous?

“Chocolate cysts often cause no problems but can cause significant pain,” says Dr. Martin. Complications occur when these cysts grow to a considerable size or when they are located in an area that impacts other organs or critical bodily functions. Dr. Orbuch notes that they can fall to the back of the uterus, which can then impact the bowel and rectum—and this bowel involvement can often make surgical removal a more difficult procedure.

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How Chocolate Cysts Are Detected and Treated

“Chocolate cysts are suspected based on pain or a mass on one side of the pelvis,” says Dr. Martin, adding that imaging such as an MRI or sonogram will often be used to confirm the diagnosis. The initial treatment for these cysts may involve birth control pills. “Oral contraceptives do not decrease the size of the cyst but stop additional ovulatory cysts from forming that can confuse the diagnosis,” Dr. Martin says. If these cysts grow or become painful, they are typically removed via surgery, most commonly a laparoscopic procedure.

Dr. Martin stresses the importance of early diagnosis—often a challenge with endometriosis—so the growths can be detected when treatment may be able to alleviate symptoms or remove lesions, sparing the patient further pain and additional potential problems. In her social media posts, Irwin noted that she had been plagued by symptoms for more than a decade before getting an endometriosis diagnosis—and by that time, “they found 37 lesions, some very deep and difficult to remove, and a chocolate cyst,” as she posted on Instagram.

Although Irwin’s situation was complex, her timeline is about the norm for those with this condition, as Dr. Orbuch says the average patient has symptoms for 8 to 10 years before being diagnosed with endometriosis.

Next up, see Bindi Irwin read to her daughter in endearing family snapshots.

Sources:

• Dr. Iris Kerin Orbuch, MD, endometriosis specialist, co-author of Beating Endo, and subject matter expert in the endometriosis documentary, Below The Belt

• Dr. Dan Martin, MD, Scientific and Medical Director at Endometriosis Foundation of America (EndoFound)

• Dr. Erkan Buyuk, MD, board-certified OBGYN/REI at RMA of New York